2025-10-21; City Council; 05; Adoption of Plans, Specifications, Contract Documents, Authorization to Advertise for Bids for the Veterans Memorial Park Project and the Faraday Avenue Improvements Proj — Carlsbad City Council, October 21, 2025 (part 10 of 15)

Plant-Material-Based (Short Lived, <6 months) Binders
Guar: Guar is a non-toxic, biodegradable, natural galactomannan-based hydrocolloid treated with dispersant agents for easy field mixing. It should be mixed with water at the rate of 11 to 15 lb per 1,000 gallons. Recommended minimum application rates are as follows:

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Application Rates for Guar Soil Stabilizer
Slope (H:V): Flat 4:1 3:1 2:1 1:1
lb/acre: 40 45 50 60 70
Psyllium: Psyllium is composed of the finely ground muciloid coating of plantago seeds that is applied as a dry powder or in a wet slurry to the surface of the soil. It dries to form a firm but rewettable membrane that binds soil particles together but permits germination and growth of seed. Psyllium requires 12 to 18 hours drying time. Application rates should be from 80 to 200 lb/acre, with enough water in solution to allow for a uniform slurry flow.

Starch: Starch is non-ionic, cold water soluble (pre-gelatinized) granular cornstarch. The material is mixed with water and applied at the rate of 150 lb/acre. Approximate drying time is 9 to 12 hours.

Plant-Material-Based (Long Lived, 6-12 months) Binders
Pitch and Rosin Emulsion: Generally, a non-ionic pitch and rosin emulsion has a minimum solids content of 48%. The rosin should be a minimum of 26% of the total solids content. The soil stabilizer should be non-corrosive, water dilutable emulsion that upon application cures to a water insoluble binding and cementing agent. For soil erosion control applications, the emulsion is diluted and should be applied as follows:
 For clayey soil: 5 parts water to 1-part emulsion
 For sandy soil: 10 parts water to 1-part emulsion
Application can be by water truck or hydraulic seeder with the emulsion and product mixture applied at the rate specified by the manufacturer.

Polymeric Emulsion Blend Binders
Acrylic Copolymers and Polymers: Polymeric soil stabilizers should consist of a liquid or solid polymer or copolymer with an acrylic base that contains a minimum of 55% solids. The polymeric compound should be handled and mixed in a manner that will not cause foaming or should contain an anti-foaming agent. The polymeric emulsion should not exceed its shelf life or expiration date; manufacturers should provide the expiration date. Polymeric soil stabilizer should be readily miscible in water, non-injurious to seed or animal life, non-flammable, should provide surface soil stabilization for various soil types without totally inhibiting water infiltration, and should not re-emulsify when cured. The applied compound typically requires 12 to 24 hours drying time. Liquid copolymer should be diluted at a rate of 10 parts water to 1- part polymer and the mixture applied to soil at a rate of 1,175 gallons/acre.

Liquid Polymers of Methacrylates and Acrylates: This material consists of a tackifier/sealer that is a liquid polymer of methacrylates and acrylates. It is an aqueous 100% acrylic emulsion blend of 40% solids by volume that is free from styrene, acetate, vinyl, ethoxylated surfactants or silicates. For soil stabilization applications, it is diluted with water in accordance with the manufacturer’s recommendations and applied with a hydraulic seeder at the rate of 20 gallons/acre. Drying time is 12 to 18 hours after application.

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Copolymers of Sodium Acrylates and Acrylamides: These materials are non-toxic, dry powders that are copolymers of sodium acrylate and acrylamide. They are mixed with water and applied to the soil surface for erosion control at rates that are determined by slope gradient:

Slope Gradient (H:V) lb/acre
Flat to 5:1 3.0 – 5.0
5:1 to 3:1 5.0 – 10.0
2:1 to 1:1 10.0 – 20.0

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Poly-Acrylamide (PAM) and Copolymer of Acrylamide: Linear copolymer polyacrylamide for use as a soil binder is packaged as a dry flowable solid, as a liquid. Refer to the manufacturer’s recommendation for dilution and application rates as they vary based on liquid or dry form, site conditions and climate.
 Limitations specific to PAM are as follows:
Do not use PAM on a slope that flows into a water body without passing through a sediment trap or sediment basin.
The specific PAM copolymer formulation must be anionic. Cationic PAM should not be used in any application because of known aquatic toxicity problems. Only the highest drinking water grade PAM, certified for compliance with ANSI/NSF Standard 60 for drinking water treatment, should be used for soil applications. PAM designated for erosion and sediment control should be “water soluble” or “linear” or “non-cross linked”.
PAM should not be used as a stand-alone BMP to protect against water-based erosion.

When combined with mulch, its effectiveness increases dramatically.

Hydro-Colloid Polymers: Hydro-Colloid Polymers are various combinations of dry flowable poly-acrylamides, copolymers and hydro-colloid polymers that are mixed with water and applied to the soil surface at rates of 55 to 60 lb/acre. Drying times are 0 to 4 hours.

Cementitious-Based Binders
Gypsum: This is a formulated gypsum-based product that readily mixes with water and mulch to form a thin protective crust on the soil surface. It is composed of high purity gypsum that is ground, calcined and processed into calcium sulfate hemihydrate with a minimum purity of 86%. It is mixed in a hydraulic seeder and applied at rates 4,000 to 12,000 lb/acre. Drying time is 4 to 8 hours.

Applying Soil Binders
After selecting an appropriate soil binder, the untreated soil surface must be prepared before applying the soil binder. The untreated soil surface must contain sufficient moisture to assist the agent in achieving uniform distribution. In general, the following steps should be followed:
 Follow manufacturer’s written recommendations for application rates, pre-wetting of application area, and cleaning of equipment after use.
 Prior to application, roughen embankment and fill areas.  Consider the drying time for the selected soil binder and apply with sufficient time before anticipated rainfall. Soil binders should not be applied during or immediately before rainfall.
 Avoid over spray onto roads, sidewalks, drainage channels, sound walls, existing vegetation, etc.

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 Soil binders should not be applied to frozen soil, areas with standing water, under freezing or rainy conditions, or when the temperature is below 40°F during the curing period.  More than one treatment is often necessary, although the second treatment may be diluted or have a lower application rate.
 Generally, soil binders require a minimum curing time of 24 hours before they are fully effective. Refer to manufacturer's instructions for specific cure time.  For liquid agents:
Crown or slope ground to avoid ponding.
Uniformly pre-wet ground at 0.03 to 0.3 gal/yd2 or according to manufacturer’s recommendations.
Apply solution under pressure. Overlap solution 6 to 12 in. Allow treated area to cure for the time recommended by the manufacturer; typically, at least 24 hours.
Apply second treatment before first treatment becomes ineffective, using 50% application rate.
In low humidities, reactivate chemicals by re-wetting with water at 0.1 to 0.2 gal/yd2.

Costs
Costs vary according to the soil stabilizer selected for implementation. The following are approximate installed costs:

Soil Binder Cost per Acre
Plant-Material-Based (Short Lived) Binders $900-$1,200
Plant-Material-Based (Long Lived) Binders $1,500-$1,900 Polymeric Emulsion Blend Binders $900-$1,900
Cementitious-Based Binders $1,000-$1,500
Source: Cost information received from individual product manufacturers solicited by Geosyntec Consultants (2004). Adjusted for inflation (2016 dollars) by Tetra Tech Inc.

Care should be exercised to minimize the damage to protected areas while making repairs, as any area damaged will require re-application of BMPs.

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 Reapply the selected soil binder as needed to maintain effectiveness.

Table 1 Properties of Soil Binders for Erosion Control
Evaluation Criteria
Binder Type
Plant Material Based (Short
Lived)
Plant Material Based (Long
Lived)
Polymeric
Emulsion Blends
Cementitious-
Based Binders
Relative Cost Low Moderate to High Low to High Low to Moderate Resistance to Leaching High High Low to Moderate Moderate Resistance to Abrasion Moderate Low Moderate to High Moderate to High Longevity Short to Medium Medium Medium to Long Medium
Minimum Curing Time
before Rain 9 to 18 hours 19 to 24 hours 0 to 24 hours 4 to 8 hours Compatibility with Existing Vegetation Good Poor Poor Poor Mode of Degradation Biodegradable Biodegradable
Photodegradable/
Chemically
Degradable
Photodegradable/
Chemically
Degradable
Labor Intensive No No No No
Specialized Application Equipment
Water Truck or Hydraulic Mulcher
Water Truck or Hydraulic Mulcher
Water Truck or Hydraulic Mulcher Water Truck or Hydraulic Mulcher Liquid/Powder Powder Liquid Liquid/Powder Powder
Surface Crusting Yes, but dissolves
on rewetting Yes Yes, but dissolves on
rewetting Yes
Clean Up Water Water Water Water
Erosion Control Application Rate Varies (1) Varies (1) Varies (1) 4,000 to 12,000 lbs/acre (1) See Implementation for specific rates.

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References
Erosion Control Pilot Study Report, State of California Department of Transportation (Caltrans), June 2000.

Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

Sedimentation and Erosion Control, An Inventory of Current Practices Draft, US EPA, April 1990.

Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Guidance Document: Soil Stabilization for Temporary Slopes, State of California Department of Transportation (Caltrans), November 1999.

Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992.

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Description and Purpose
Rolled Erosion Control Products (RECPs), also known as
erosion control matting or blankets, can be made of natural or synthetic materials or a combination of the two. RECPs are used to cover the soil surface to reduce erosion from rainfall impact, hold soil in place, and absorb and hold moisture near the soil surface. Additionally, RECPs may be used to stabilize soils until vegetation is established or to reinforce non-woody surface vegetation.

Suitable Applications
RECPs are typically applied on slopes where erosion hazard is high, and vegetation will be slow to establish. Mattings are also used on stream banks, swales and other drainage channels where moving water at velocities between 3 ft/s and 6 ft/s are likely to cause scour and wash out new vegetation and in areas where the soil surface is disturbed and where existing
vegetation has been removed. RECPs may also be used when seeding cannot occur (e.g., late season construction and/or the arrival of an early rain season). RECPs should be considered when the soils are fine grained and potentially erosive. RECPs should be considered in the following situations:
 Steep slopes, generally steeper than 3:1 (H:V).
 Long slopes.
 Slopes where the erosion potential is high.
 Slopes and disturbed soils where mulch must be anchored.

Categories
EC Erosion Control 
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control 
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
EC-3 Hydraulic Mulch
EC-4 Hydroseeding
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

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 Disturbed areas where temporary cover is needed, or plants are slow to establish or will not establish.
 Channels with flows exceeding 3.3 ft/s.
 Channels to be vegetated.
 Stockpiles.
 Slopes adjacent to water bodies.

Limitations
 RECP installed costs are generally higher than other erosion control BMPs, limiting their use to areas where other BMPs are ineffective (e.g., channels, steep slopes).  RECPs may delay seed germination, due to reduction in soil temperature and/or sunlight.  RECPs are generally not suitable for excessively rocky sites or areas where the final vegetation will be mowed (since staples and netting can catch in mowers). If a staple or pin cannot be driven into the soil because the underlying soil is too hard or rocky, then an alternative BMP should be selected.
 If used for temporary erosion control, RECPs should be removed and disposed of prior to application of permanent soil stabilization measures.
 The use of plastic sheeting should be limited to covering stockpiles or very small graded areas for short periods of time (such as through one imminent storm event) until other measures, such as seeding and mulching, may be installed. - Plastic sheeting is easily vandalized, easily torn, photodegradable, and must be disposed of at a landfill.
- Plastic sheeting results in 100% runoff, which may cause serious erosion problems in the areas receiving the increased flow.
 According to the State Water Board’s CGP Review, Issue #2, only RECPs that either do not contain plastic netting or contain netting manufactured from 100% biodegradable non- plastic materials, such as jute, sisal, or coir fiber should be used due to plastic pollution and wildlife concerns. If a plastic-netted product is used for temporary stabilization, it must be promptly removed when no longer needed and removed or replaced with non-plastic netted RECPs for final stabilization.
 RECPs may have limitations based on soil type, slope gradient, or channel flow rate; consult the manufacturer for proper selection.
 Not suitable for areas that have foot traffic (tripping hazard) – e.g., pad areas around buildings under construction.
 RECPs that incorporate a plastic netting (e.g. straw blanket typically uses a plastic netting to hold the straw in place) may not be suitable near known wildlife habitat. Wildlife can become trapped in the plastic netting. As per State Water Board guidance, RECPs that

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contain plastic netting are discouraged for temporary controls and are not acceptable alternatives for permanent controls. RECPs that do not contain plastic netting or contain netting manufactured from 100% biodegradable non-plastic materials such as jute, sisal, or coir fiber should be used.
 RECPs may have limitations in extremely windy climates; they are susceptible to wind damage and displacement. However, when RECPs are properly trenched at the top and bottom and stapled in accordance with the manufacturer’s recommendations, problems with wind can be minimized.

Implementation
Material Selection
 Natural RECPs have been found to be effective where re-vegetation will be provided by re- seeding. The choice of material should be based on the size of area, side slopes, surface conditions such as hardness, moisture, weed growth, and availability of materials.  Additional guidance on the comparison and selection of temporary slope stabilization methods is provided in Appendix F of the Handbook.
 The following natural and synthetic RECPs are commonly used:

Geotextiles
 Material can be a woven or a non-woven polypropylene fabric with minimum thickness of

0.06 in., minimum width of 12 ft and should have minimum tensile strength of 150 lbs (warp), 80 lbs (fill) in conformance with the requirements in ASTM Designation: D 4632.

The permittivity of the fabric should be approximately 0.07 sec–1 in conformance with the requirements in ASTM Designation: D4491. The fabric should have an ultraviolet (UV) stability of 70 percent in conformance with the requirements in ASTM designation: D4355.

Geotextile blankets must be secured in place with wire staples or sandbags and by keying into tops of slopes to prevent infiltration of surface waters under geotextile. Staples should be made of minimum 11-gauge steel wire and should be U-shaped with 8 in. legs and 2 in. crown.
 Geotextiles may be reused if they are suitable for the use intended.

Plastic Covers
 Generally plastic sheeting should only be used as stockpile covering or for very small graded areas for short periods of time (such as through one imminent storm event). If plastic sheeting must be used, choose a plastic that will withstand photo degradation.  Plastic sheeting should have a minimum thickness of 6 mils and must be keyed in at the top of slope (when used as a temporary slope protection) and firmly held in place with sandbags or other weights placed no more than 10 ft apart. Seams are typically taped or weighted down their entire length, and there should be at least a 12 in. to 24 in. overlap of all seams.

Edges should be embedded a minimum of 6 in. in soil (when used as a temporary slope protection).
 All sheeting must be inspected periodically after installation and after significant rainstorms to check for erosion, undermining, and anchorage failure. Any failures must be repaired

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immediately. If washout or breakages occur, the material should be re-installed after repairing the damage to the slope.

Erosion Control Blankets/Mats
 Biodegradable RECPs are typically composed of jute fibers, curled wood fibers, straw, coconut fiber, or a combination of these materials. In order for an RECP to be considered 100% biodegradable, the netting, sewing or adhesive system that holds the biodegradable mulch fibers together must also be biodegradable. See typical installation details at the end of this fact sheet.
Jute is a natural fiber that is made into a yarn that is loosely woven into a biodegradable mesh. The performance of jute as a stand-alone RECP is low. Most other RECPs outperform jute as a temporary erosion control product and therefore jute is not commonly used. It is designed to be used in conjunction with vegetation. The material is supplied in rolled strips, which should be secured to the soil with U-shaped staples or stakes in accordance with manufacturers’ recommendations. Excelsior (curled wood fiber) blanket material should consist of machine produced mats of curled wood excelsior with 80 percent of the fiber 6 in. or longer. The excelsior blanket should be of consistent thickness. The wood fiber must be evenly distributed over the entire area of the blanket. The top surface of the blanket should be covered with a photodegradable extruded plastic mesh. The blanket should be smolder resistant without the use of chemical additives and should be non-toxic and non-injurious to plant and animal life. Excelsior blankets should be furnished in rolled strips, a minimum of 48 in. wide, and should have an average weight of 0.8 lb/yd2, ±10 percent, at the time of manufacture. Excelsior blankets must be secured in place with wire staples. Staples should be made of minimum 11-gauge steel wire and should be U-shaped with 8 in. legs and 2 in. crown.
Straw blanket should be machine produced mats of straw with a lightweight biodegradable netting top layer. The straw should be attached to the netting with biodegradable thread or glue strips. The straw blanket should be of consistent thickness.

The straw should be evenly distributed over the entire area of the blanket. Straw blanket should be furnished in rolled strips a minimum of 6.5 ft wide, a minimum of 80 ft long and a minimum of 0.5 lb/yd2. Straw blankets must be secured in place with wire staples.

Staples should be made of minimum 11-gauge steel wire and should be U-shaped with 8 in. legs and 2 in. crown.
Wood fiber blanket is composed of biodegradable fiber mulch with extruded plastic netting held together with adhesives. The material is designed to enhance re-vegetation.

The material is furnished in rolled strips, which must be secured to the ground with U- shaped staples or stakes in accordance with manufacturers’ recommendations. Coconut fiber blanket should be a machine produced mat of 100 percent coconut fiber with biodegradable netting on the top and bottom. The coconut fiber should be attached to the netting with biodegradable thread or glue strips. The coconut fiber blanket should be of consistent thickness. The coconut fiber should be evenly distributed over the entire area of the blanket. Coconut fiber blanket should be furnished in rolled strips with a minimum of 6.5 ft wide, a minimum of 80 ft. long and a minimum of 0.5

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lb/yd2. Coconut fiber blankets must be secured in place with wire staples. Staples should be made of minimum 11-gauge steel wire and should be U-shaped with 8 in. legs and 2 in. crown.
Coconut fiber mesh is a thin permeable membrane made from coconut or corn fiber that is spun into a yarn and woven into a biodegradable mat. It is designed to be used in conjunction with vegetation and typically has longevity of several years. The material is supplied in rolled strips, which must be secured to the soil with U-shaped staples or stakes in accordance with manufacturers’ recommendations. Straw coconut fiber blanket should be machine produced mats of 70 percent straw and 30 percent coconut fiber with a biodegradable netting top layer and a biodegradable bottom net. The straw and coconut fiber should be attached to the netting with biodegradable thread or glue strips. The straw coconut fiber blanket should be of consistent thickness. The straw and coconut fiber should be evenly distributed over the entire area of the blanket. Straw coconut fiber blanket should be furnished in rolled strips a minimum of 6.5 ft wide, a minimum of 80 ft long and a minimum of 0.5 lb/yd2.

Straw coconut fiber blankets must be secured in place with wire staples. Staples should be made of minimum 11-gauge steel wire and should be U-shaped with 8 in. legs and 2 in. crown.
 Non-biodegradable RECPs are typically composed of polypropylene, polyethylene, nylon or other synthetic fibers. In some cases, a combination of biodegradable and synthetic fibers is used to construct the RECP. Netting used to hold these fibers together is typically non- biodegradable as well. Only biodegradable RECPs can remain on a site applying for a Notice of Termination due to plastic pollution and wild life concerns (State Waterboard, 2016).

RECPs containing plastic that are used on a site must be disposed of for final stabilization. Plastic netting is a lightweight biaxially oriented netting designed for securing loose mulches like straw or paper to soil surfaces to establish vegetation. The netting is photodegradable. The netting is supplied in rolled strips, which must be secured with U- shaped staples or stakes in accordance with manufacturers’ recommendations. Plastic mesh is an open weave geotextile that is composed of an extruded synthetic fiber woven into a mesh with an opening size of less than ¼ in. It is used with re- vegetation or may be used to secure loose fiber such as straw to the ground. The material is supplied in rolled strips, which must be secured to the soil with U-shaped staples or stakes in accordance with manufacturers’ recommendations. Synthetic fiber with netting is a mat that is composed of durable synthetic fibers treated to resist chemicals and ultraviolet light. The mat is a dense, three-dimensional mesh of synthetic (typically polyolefin) fibers stitched between two polypropylene nets.

The mats are designed to be re-vegetated and provide a permanent composite system of soil, roots, and geomatrix. The material is furnished in rolled strips, which must be secured with U-shaped staples or stakes in accordance with manufacturers’ recommendations.
Bonded synthetic fibers consist of a three-dimensional geometric nylon (or other synthetic) matting. Typically, it has more than 90 percent open area, which facilitates

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root growth. It’s tough root reinforcing system anchors vegetation and protects against hydraulic lift and shear forces created by high volume discharges. It can be installed over prepared soil, followed by seeding into the mat. Once vegetated, it becomes an invisible composite system of soil, roots, and geomatrix. The material is furnished in rolled strips that must be secured with U-shaped staples or stakes in accordance with manufacturers’ recommendations.
Combination synthetic and biodegradable RECPs consist of biodegradable fibers, such as wood fiber or coconut fiber, with a heavy polypropylene net stitched to the top and a high strength continuous filament geomatrix or net stitched to the bottom. The material is designed to enhance re-vegetation. The material is furnished in rolled strips, which must be secured with U-shaped staples or stakes in accordance with manufacturers’ recommendations.

Site Preparation
 Proper soil preparation is essential to ensure complete contact of the RECP with the soil. Soil Roughening is not recommended in areas where RECPs will be installed.  Grade and shape the area of installation.
 Remove all rocks, clods, vegetation or other obstructions so that the installed blankets or mats will have complete, direct contact with the soil.
 Prepare seedbed by loosening 2 to 3 in. of topsoil.

Seeding/Planting
Seed the area before blanket installation for erosion control and re-vegetation. Seeding after mat installation is often specified for turf reinforcement application. When seeding prior to blanket installation, all areas disturbed during blanket installation must be re-seeded. Where soil filling is specified for turf reinforcement mats (TRMs), seed the matting and the entire disturbed area after installation and prior to filling the mat with soil.

Fertilize and seed in accordance with seeding specifications or other types of landscaping plans.

The protective matting can be laid over areas where grass has been planted and the seedlings have emerged. Where vines or other ground covers are to be planted, lay the protective matting first and then plant through matting according to design of planting.

Check Slots
Check slots shall be installed as required by the manufacturer.

Laying and Securing Matting
 Before laying the matting, all check slots should be installed and the seedbed should be friable, made free from clods, rocks, and roots. The surface should be compacted and finished according to the requirements of the manufacturer’s recommendations.  Mechanical or manual lay down equipment should be capable of handling full rolls of fabric and laying the fabric smoothly without wrinkles or folds. The equipment should meet the fabric manufacturer’s recommendations or equivalent standards.

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Anchoring
 U-shaped wire staples, metal geotextile stake pins, or triangular wooden stakes can be used to anchor mats and blankets to the ground surface.
 Wire staples should be made of minimum 11-gauge steel wire and should be U-shaped with 8 in. legs and 2 in. crown.
 Metal stake pins should be 0.188 in. diameter steel with a 1.5 in. steel washer at the head of the pin, and 8 in. in length.
 Wire staples and metal stakes should be driven flush to the soil surface.

Installation on Slopes
Installation should be in accordance with the manufacturer's recommendations. In general, these will be as follows:
 Begin at the top of the slope and anchor the blanket in a 6 in. deep by 6 in. wide trench.

Backfill trench and tamp earth firmly.
 Unroll blanket down slope in the direction of water flow.  Overlap the edges of adjacent parallel rolls 2 to 3 in. and staple every 3 ft (or greater, per manufacturer’s specifications).
 When blankets must be spliced, place blankets end over end (shingle style) with 6 in. overlap. Staple through overlapped area, approximately 12 in. apart.  Lay blankets loosely and maintain direct contact with the soil. Do not stretch.  Staple blankets sufficiently to anchor blanket and maintain contact with the soil. Staples should be placed down the center and staggered with the staples placed along the edges.

Steep slopes, 1:1 (H:V) to 2:1 (H:V), require a minimum of 2 staples/yd2. Moderate slopes, 2:1 (H:V) to 3:1 (H:V), require a minimum of 1 ½ staples/yd2. Check manufacturer’s specifications to determine if a higher density staple pattern is required.

Installation in Channels
Installation should be in accordance with the manufacturer's recommendations. In general, these will be as follows:
 Dig initial anchor trench 12 in. deep and 6 in. wide across the channel at the lower end of the project area.
 Excavate intermittent check slots, 6 in. deep and 6 in. wide across the channel at 25 to 30 ft intervals along the channels.
 Cut longitudinal channel anchor trenches 4 in. deep and 4 in. wide along each side of the installation to bury edges of matting, whenever possible extend matting 2 to 3 in. above the crest of the channel side slopes.

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 Beginning at the downstream end and in the center of the channel, place the initial end of the first roll in the anchor trench and secure with fastening devices at 12 in. intervals. Note:
matting will initially be upside down in anchor trench.  In the same manner, position adjacent rolls in anchor trench, overlapping the preceding roll a minimum of 3 in.
 Secure these initial ends of mats with anchors at 12 in. intervals, backfill and compact soil.  Unroll center strip of matting upstream. Stop at next check slot or terminal anchor trench.

Unroll adjacent mats upstream in similar fashion, maintaining a 3 in. overlap.  Fold and secure all rolls of matting snugly into all transverse check slots. Lay mat in the bottom of the slot then fold back against itself. Anchor through both layers of mat at 12 in. intervals, then backfill and compact soil. Continue rolling all mat widths upstream to the next check slot or terminal anchor trench.
 Alternate method for non-critical installations: Place two rows of anchors on 6 in. centers at 25 to 30 ft. intervals in lieu of excavated check slots.  Staple shingled lap spliced ends a minimum of 12 in. apart on 12 in. intervals.  Place edges of outside mats in previously excavated longitudinal slots; anchor using prescribed staple pattern, backfill, and compact soil.
 Anchor, fill, and compact upstream end of mat in a 12 in. by 6 in. terminal trench.  Secure mat to ground surface using U-shaped wire staples, geotextile pins, or wooden stakes.  Seed and fill turf reinforcement matting with soil, if specified.

Soil Filling (if specified for turf reinforcement mat (TRM)) Installation should be in accordance with the manufacturer’s recommendations. Typical installation guidelines are as follows:

 After seeding, spread and lightly rake ½-3/4 inches of fine topsoil into the TRM apertures to completely fill TRM thickness. Use backside of rake or other flat implement.  Alternatively, if allowed by product specifications, spread topsoil using lightweight loader, backhoe, or other power equipment. Avoid sharp turns with equipment.  Always consult the manufacturer's recommendations for installation.  Do not drive tracked or heavy equipment over mat.
 Avoid any traffic over matting if loose or wet soil conditions exist.  Use shovels, rakes, or brooms for fine grading and touch up.  Smooth out soil filling just exposing top netting of mat.

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Temporary Soil Stabilization Removal
 Temporary soil stabilization removed from the site of the work must be disposed of if necessary.

Costs
Installed costs can be relatively high compared to other BMPs. Approximate costs for installed materials are shown below:

Rolled Erosion Control Products Installed Cost per Acre Biodegradable
Jute Mesh $7,700-$9,000
Curled Wood Fiber $10,200-$13,400
Straw $10,200-$13,400
Wood Fiber $10,200-$13,400
Coconut Fiber $16,600-$18,000
Coconut Fiber Mesh $38,400-$42,200
Straw Coconut Fiber $12,800-$15,400
Non-Biodegradable
Plastic Netting $2,600-$2,800
Plastic Mesh $3,800-$4,500
Synthetic Fiber with Netting $43,500-$51,200
Bonded Synthetic Fibers $57,600-$70,400
Combination with Biodegradable $38,400-$46,100
Source: Cost information received from individual product manufacturers solicited by Geosyntec Consultants (2004). Adjusted for inflation (2016 dollars) by Tetra Tech, Inc.

Inspection and Maintenance
 RECPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Areas where erosion is evident shall be repaired and BMPs reapplied as soon as possible.

Care should be exercised to minimize the damage to protected areas while making repairs, as any area damaged will require reapplication of BMPs.
 If washout or breakage occurs, re-install the material after repairing the damage to the slope or channel.
 Make sure matting is uniformly in contact with the soil.  Check that all the lap joints are secure.
 Check that staples are flush with the ground.

Geotextiles and Mats EC-7
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References
CGP Review #2, State Water Resources Control Board, 2014. Available online at:
http://www.waterboards.ca.gov/water_issues/programs/stormwater/docs/training/cgp_revie w_issue2.pdf.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005
Erosion Control Pilot Study Report, State of California Department of Transportation (Caltrans), June 2000.

Guides for Erosion and Sediment Controls in California, USDA Soils Conservation Service, January 1991.

National Management Measures to Control Nonpoint Source Pollution from Urban Areas, United States Environmental Protection Agency, 2002.

Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Guidance Document: Soil Stabilization for Temporary Slopes, State of California Department of Transportation (Caltrans), November 1999.

Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992.

Water Quality Management Plan for The Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988.

Geotextiles and Mats EC-7
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Geotextiles and Mats EC-7
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Earth Dikes and Drainage Swales EC-9
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Description and Purpose
An earth dike is a temporary berm or ridge of compacted soil used to divert runoff or channel water to a desired location. A drainage swale is a shaped and sloped depression in the soil surface used to convey runoff to a desired location. Earth dikes and drainage swales are used to divert off site runoff around the construction site, divert runoff from stabilized areas and disturbed areas, and direct runoff into sediment basins or traps.

Suitable Applications
Earth dikes and drainage swales are suitable for use,
individually or together, where runoff needs to be diverted from one area and conveyed to another.
 Earth dikes and drainage swales may be used:
To convey surface runoff down sloping land
To intercept and divert runoff to avoid sheet flow over sloped surfaces
To divert and direct runoff towards a stabilized
watercourse, drainage pipe or channel
To intercept runoff from paved surfaces
To intercept and divert run-on
Below steep grades where runoff begins to concentrate Categories
EC Erosion Control 
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
None
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Earth Dikes and Drainage Swales EC-9
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Along roadways and facility improvements subject to flood drainage At the top of slopes to divert runon from adjacent or undisturbed slopes At bottom and mid slope locations to intercept sheet flow and convey concentrated flows Divert sediment laden runoff into sediment basins or traps Limitations
Dikes should not be used for drainage areas greater than 10 acres or along slopes greater than 10 percent. For larger areas more permanent drainage structures should be built. All drainage structures should be built in compliance with local municipal requirements.  Earth dikes may create more disturbed area on site and become barriers to construction equipment.
 Earth dikes must be stabilized immediately, which adds cost and maintenance concerns.  Diverted stormwater may cause downstream flood damage.  Dikes should not be constructed of soils that may be easily eroded.  Regrading the site to remove the dike may add additional cost.  Temporary drains and swales or any other diversion of runoff should not adversely impact upstream or downstream properties.
 Temporary drains and swales must conform to local floodplain management requirements.  Earth dikes/drainage swales are not suitable as sediment trapping devices.  It may be necessary to use other soil stabilization and sediment controls such as check dams, plastics, and blankets, to prevent scour and erosion in newly graded dikes, swales, and ditches.
 Sediment accumulation, scour depressions, and/or persistent non-stormwater discharges can result in areas of standing water suitable for mosquito production in drainage swales.

Implementation
The temporary earth dike is a berm or ridge of compacted soil, located in such a manner as to divert stormwater to a sediment trapping device or a stabilized outlet, thereby reducing the potential for erosion and offsite sedimentation. Earth dikes can also be used to divert runoff from off site and from undisturbed areas away from disturbed areas and to divert sheet flows away from unprotected slopes.

An earth dike does not itself control erosion or remove sediment from runoff. A dike prevents erosion by directing runoff to an erosion control device such as a sediment trap or directing runoff away from an erodible area. Temporary diversion dikes should not adversely impact adjacent properties and must conform to local floodplain management regulations and should not be used in areas with slopes steeper than 10%.

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Slopes that are formed during cut and fill operations should be protected from erosion by runoff.

A combination of a temporary drainage swale and an earth dike at the top of a slope can divert runoff to a location where it can be brought to the bottom of the slope (see EC-11, Slope Drains).

A combination dike and swale is easily constructed by a single pass of a bulldozer or grader and compacted by a second pass of the tracks or wheels over the ridge. Diversion structures should be installed when the site is initially graded and remain in place until post construction BMPs are installed and the slopes are stabilized.

Diversion practices concentrate surface runoff, increasing its velocity and erosive force. Thus, the flow out of the drain or swale must be directed onto a stabilized area or into a grade stabilization structure. If significant erosion will occur, a swale should be stabilized using vegetation, chemical treatment, rock rip-rap, matting, or other physical means of stabilization.

Any drain or swale that conveys sediment laden runoff must be diverted into a sediment basin or trap before it is discharged from the site.

General
 Care must be applied to correctly size and locate earth dikes, drainage swales. Excessively steep, unlined dikes, and swales are subject to erosion and gully formation.  Conveyances should be stabilized.
 Use a lined ditch for high flow velocities.
 Select flow velocity based on careful evaluation of the risks due to erosion of the measure, soil types, overtopping, flow backups, washout, and drainage flow patterns for each project site.
 Compact any fills to prevent unequal settlement.
 Do not divert runoff onto other property without securing written authorization from the property owner.
 When possible, install and utilize permanent dikes, swales, and ditches early in the construction process.
 Provide stabilized outlets.

Earth Dikes
Temporary earth dikes are a practical, inexpensive BMP used to divert stormwater runoff.

Temporary diversion dikes should be installed in the following manner:
 All dikes should be compacted by earth moving equipment.  All dikes should have positive drainage to an outlet.  All dikes should have 2:1 or flatter side slopes, 18 in. minimum height, and a minimum top width of 24 in. Wide top widths and flat slopes are usually needed at crossings for construction traffic.

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 May be covered with hydro mulch, hydroseed, wood mulch, compost blanket, or RECP for stabilization.
 The outlet from the earth dike must function with a minimum of erosion. Runoff should be conveyed to a sediment trapping device such as a Sediment Trap (SE-3) or Sediment Basin (SE-2) when either the dike channel or the drainage area above the dike are not adequately stabilized.
 Temporary stabilization may be achieved using seed and mulching for slopes less than 5% and either rip-rap or sod for slopes in excess of 5%. In either case, stabilization of the earth dike should be completed immediately after construction or prior to the first rain.  If riprap is used to stabilize the channel formed along the toe of the dike, the following typical specifications apply:

Channel Grade Riprap Stabilization

0.5-1.0% 4 in. Rock

1.1-2.0% 6 in. Rock

2.1-4.0% 8 in. Rock

4.1-5.0% 8 in. -12 in. Riprap

 The stone riprap, recycled concrete, etc. used for stabilization should be pressed into the soil with construction equipment.
 Filter cloth may be used to cover dikes in use for long periods.  Construction activity on the earth dike should be kept to a minimum.

Drainage Swales
Drainage swales are only effective if they are properly installed. Swales are more effective than dikes because they tend to be more stable. The combination of a swale with a dike on the downhill side is the most cost-effective diversion.

Standard engineering design criteria for small open channel and closed conveyance systems should be used (see the local drainage design manual). Unless local drainage design criteria state otherwise, drainage swales should be designed as follows:
 No more than 5 acres may drain to a temporary drainage swale.  Place drainage swales above or below, not on, a cut or fill slope.  Swale bottom width should be at least 2 ft.
 Depth of the swale should be at least 18 in.
 Side slopes should be 2:1 or flatter.
 Drainage or swales should be laid at a grade of at least 1 %, but not more than 15 %.

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 The swale must not be overtopped by the peak discharge from a 10-year storm, irrespective of the design criteria stated above.
 Remove all trees, stumps, obstructions, and other objectionable material from the swale when it is built.
 Compact any fill material along the path of the swale.  Stabilize all swales immediately. Seed and mulch swales at a slope of less than 5 % and use rip-rap or sod for swales with a slope between 5 and 15 %. For temporary swales, geotextiles and mats (EC-7) may provide immediate stabilization.
 Irrigation may be required to establish sufficient vegetation to prevent erosion.  Do not operate construction vehicles across a swale unless a stabilized crossing is provided.  Permanent drainage facilities must be designed by a professional engineer (see the local drainage design criteria for proper design).
 At a minimum, the drainage swale should conform to predevelopment drainage patterns and capacities.
 Construct the drainage swale with a positive grade to a stabilized outlet.  Provide erosion protection or energy dissipation measures if the flow out of the drainage swale can reach an erosive velocity.

Costs
 Cost ranges from $19 to $70 per ft. for both earthwork and stabilization and depends on availability of material, site location, and access (Adjusted for inflation (2016 dollars) by Tetra Tech, Inc.).
 Small dikes: $3 - $8/linear ft.; Large dikes: $3/yd3 (Adjusted for inflation (2016 dollars) by Tetra Tech, Inc.).
 The cost of a drainage swale increases with drainage area and slope. Typical swales for controlling internal erosion are inexpensive, as they are quickly formed during routine earthwork.

Inspection and Maintenance
 Inspect BMPs prior to forecast rain, daily during extended rain events, after rain events, weekly during the rainy season, and at two-week intervals during the non-rainy season.  Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges occur.
 Inspect ditches and berms for washouts. Replace lost riprap, damaged linings or soil stabilizers as needed.

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 Inspect channel linings, embankments, and beds of ditches and berms for erosion and accumulation of debris and sediment. Remove debris and sediment and repair linings and embankments as needed.
 Temporary conveyances should be completely removed as soon as the surrounding drainage area has been stabilized or at the completion of construction References
Erosion and Sediment Control Handbook, S.J. Goldman, K. Jackson, T.A. Bursetynsky, P.E., McGraw Hill Book Company, 1986.

Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

Metzger, M.E. 2004. Managing mosquitoes in stormwater treatment devices. University of California Division of Agriculture and Natural Resources, Publication 8125. On-line: http:// anrcatalog.ucdavis.edu/pdf/8125.pdf
National Association of Home Builders (NAHB). Stormwater Runoff & Nonpoint Source Pollution Control Guide for Builders and Developers. National Association of Home Builders, Washington, D.C., 1995
National Management Measures to Control Nonpoint Source Pollution from Urban Areas, United States Environmental Protection Agency, 2002.

Southeastern Wisconsin Regional Planning Commission (SWRPC). Costs of Urban Nonpoint Source Water Pollution Control Measures. Technical Report No. 31. Southeastern Wisconsin Regional Planning Commission, Waukesha, WI. 1991
Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992.

Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988.

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Velocity Dissipation Devices EC-10
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Description and Purpose
Outlet protection is a physical device composed of rock, grouted riprap, or concrete rubble, which is placed at the outlet of a pipe or channel to prevent scour of the soil caused by concentrated, high velocity flows.

Suitable Applications
Whenever discharge velocities and energies at the outlets of culverts, conduits, or channels are sufficient to erode the next downstream reach. This includes temporary diversion
structures to divert runon during construction.
 These devices may be used at the following locations:
− Outlets of pipes, drains, culverts, slope drains, diversion ditches, swales, conduits, or channels.
− Outlets located at the bottom of mild to steep slopes. − Discharge outlets that carry continuous flows of water. − Outlets subject to short, intense flows of water, such as flash floods.
− Points where lined conveyances discharge to unlined
conveyances
Limitations
 Large storms or high flows can wash away the rock outlet protection and leave the area susceptible to erosion.

Categories
EC Erosion Control 
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
None
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Velocity Dissipation Devices EC-10
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 Sediment captured by the rock outlet protection may be difficult to remove without removing the rock.
 Outlet protection may negatively impact the channel habitat.  Grouted riprap may break up in areas of freeze and thaw.  If there is not adequate drainage, and water builds up behind grouted riprap, it may cause the grouted riprap to break up due to the resulting hydrostatic pressure.  Sediment accumulation, scour depressions, and/or persistent non-stormwater discharges can result in areas of standing water suitable for mosquito production in velocity dissipation devices.

Implementation
General
Outlet protection is needed where discharge velocities and energies at the outlets of culverts, conduits or channels are sufficient to erode the immediate downstream reach. This practice protects the outlet from developing small eroded pools (plange pools) and protects against gully erosion resulting from scouring at a culvert mouth.

Design and Layout
As with most channel design projects, depth of flow, roughness, gradient, side slopes, discharge rate, and velocity should be considered in the outlet design. Compliance to local and state regulations should also be considered while working in environmentally sensitive streambeds.

General recommendations for rock size and length of outlet protection mat are shown in the rock outlet protection figure in this BMP and should be considered minimums. The apron length and rock size gradation are determined using a combination of the discharge pipe diameter and estimate discharge rate: Select the longest apron length and largest rock size suggested by the pipe size and discharge rate. Where flows are conveyed in open channels such as ditches and swales, use the estimated discharge rate for selecting the apron length and rock size. Flows should be same as the culvert or channel design flow but never the less than the peak 5-year flow for temporary structures planned for one rainy season, or the 10-year peak flow for temporary structures planned for two or three rainy seasons.  There are many types of energy dissipaters, with rock being the one that is represented in the attached figure.
 Best results are obtained when sound, durable, and angular rock is used.  Install riprap, grouted riprap, or concrete apron at selected outlet. Riprap aprons are best suited for temporary use during construction. Grouted or wired tied rock riprap can minimize maintenance requirements.
 Rock outlet protection is usually less expensive and easier to install than concrete aprons or energy dissipaters. It also serves to trap sediment and reduce flow velocities.  Carefully place riprap to avoid damaging the filter fabric.

Velocity Dissipation Devices EC-10
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Stone 4 in. to 6 in. may be carefully dumped onto filter fabric from a height not to exceed 12 in.
Stone 8 in. to 12 in. must be hand placed onto filter fabric, or the filter fabric may be covered with 4 in. of gravel and the 8 in. to 12 in. rock may be dumped from a height not to exceed 16 in.
Stone greater than 12 in. shall only be dumped onto filter fabric protected with a layer of gravel with a thickness equal to one half the D50 rock size, and the dump height limited to twice the depth of the gravel protection layer thickness.  For proper operation of apron: Align apron with receiving stream and keep straight throughout its length. If a curve is needed to fit site conditions, place it in upper section of apron.
 Outlets on slopes steeper than 10 percent should have additional protection.

Costs
Costs are low if material is readily available. If material is imported, costs will be higher.

Average installed cost is $250 per device.

Inspection and Maintenance
 Inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Inspect BMPs subjected to non-stormwater discharges daily while non-stormwater discharges occur. Minimize areas of standing water by removing sediment blockages and filling scour depressions.
 Inspect apron for displacement of the riprap and damage to the underlying fabric. Repair fabric and replace riprap that has washed away. If riprap continues to wash away, consider using larger material.
 Inspect for scour beneath the riprap and around the outlet. Repair damage to slopes or underlying filter fabric immediately.
 Temporary devices should be completely removed as soon as the surrounding drainage area has been stabilized or at the completion of construction.

References
County of Sacramento Improvement Standards, Sacramento County, May 1989.

Erosion and Sediment Control Handbook, S.J. Goldman, K. Jackson, T.A. Bursztynsky, P.E., McGraw Hill Book Company, 1986.

Handbook of Steel Drainage & Highway Construction, American Iron and Steel Institute, 1983.

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Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

Metzger, M.E. 2004. Managing mosquitoes in stormwater treatment devices. University of California Division of Agriculture and Natural Resources, Publication 8125. On-line: http:// anrcatalog.ucdavis.edu/pdf/8125.pdf
Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, state of California Department of Transportation (Caltrans), November 2000.

Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992.

Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988.

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Pipe Diameter inches Discharge ft3/s Apron Length, La ft Rip Rap D50 Diameter Min inches
12 5
10 10
13 4
6 18
10 20
30 40
10 16
23 26
6 8
12 16
24 30
40 50
60 16
26 26
30 8
8 12
16 For larger or higher flows consult a Registered Civil Engineer Source: USDA - SCS

Soil Preparation/Roughening EC-15
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Description and Purpose
Soil Preparation/Roughening involves assessment and
preparation of surface soils for BMP installation. This can include soil testing (for seed base, soil characteristics, or nutrients), as well as roughening surface soils by mechanical methods (including sheepsfoot rolling, track walking,
scarifying, stair stepping, and imprinting) to prepare soil for additional BMPs, or to break up sheet flow. Soil Preparation can also involve tilling topsoil to prepare a seed bed and/or incorporation of soil amendments, to enhance vegetative establishment.

Suitable Applications
Soil preparation: Soil preparation is essential to proper vegetative establishment. In particular, soil preparation (i.e. tilling, raking, and amendment) is suitable for use in
combination with any soil stabilization method, including Rolled Erosion Control Products (RECPs) or sod. Soil
preparation should not be confused with roughening.

Roughening: Soil roughening is generally referred to as track walking (sometimes called imprinting) a slope, where treads from heavy equipment run parallel to the contours of the slope and act as mini terraces. Soil preparation is most effective when used in combination with erosion controls. Soil
Roughening is suitable for use as a complementary process for controlling erosion on a site. Roughening is not intended to be used as a stand-alone BMP, and should be used with perimeter controls, additional erosion control measures, grade breaks, and vegetative establishment for maximum effectiveness.

Roughening is intended to only affect surface soils and should not compromise slope stability or overall compaction. Suitable applications for soil roughening include:

Categories
EC Erosion Control 
SE Sediment Control 
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
EC-3 Hydraulic Mulch
EC-5 Soil Binders
EC-7 Geotextiles and Mats
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 Along any disturbed slopes, including temporary stockpiles, sediment basins, or compacted soil diversion berms and swales.
 Roughening should be used in combination with hydraulically applied stabilization methods, compost blanket, or straw mulch; but should not be used in combination with RECPs or sod because roughening is intended to leave terraces on the slope.

Limitations
 Preparation and roughening must take place prior to installing other erosion controls (such as hydraulically applied stabilizers) or sediment controls (such as fiber rolls) on the faces of slopes.
 In such cases where slope preparation is minimal, erosion control/revegetation BMPs that do not require extensive soil preparation - such as hydraulic mulching and seeding applications - should be employed.
 Consideration should be given to the type of erosion control BMP that follows surface preparation, as some BMPs are not designed to be installed over various types of tillage/roughening, i.e., RECPs should not be used with soil roughening due to a “bridging” effect, which suspends the blanket above the seed bed.
 Surface roughness has an effect on the amount of mulch material that needs to be applied, which shows up as a general increase in mulch material due to an increase in surface area (Topographic Index -see EC-3 Hydraulic Mulch).

Implementation
 Additional guidance on the comparison and selection of temporary slope stabilization methods is provided in Appendix F of the Handbook.

General
A roughened surface can significantly reduce erosion. Based on tests done at the San Diego State Erosion Research Laboratory, various roughening techniques on slopes can result in a 12 - 76% reduction in the erosion rate versus smooth slopes.

Materials
Minimal materials are required unless amendments and/or seed are added to the soil. The majority of soil roughening/preparation can be done with equipment that is on hand at a normal construction site, such as bull dozers and compaction equipment.

Installation Guidelines
Soil Preparation
 Where appropriate or feasible, soil should be prepared to receive the seed by disking or otherwise scarifying the surface to eliminate crust, improve air and water infiltration and create a more favorable environment for germination and growth.  Based upon soil testing conducted, apply additional soil amendments (e.g., fertilizers, additional seed) to the soil to help with germination. Follow EC-4, Hydroseeding, when selecting and applying seed and fertilizers.

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Cut Slope Roughening:
 Stair-step grade or groove the cut slopes that are steeper than 3:1.  Use stair-step grading on any erodible material soft enough to be ripped with a bulldozer.

Slopes consisting of soft rock with some subsoil are particularly suited to stair-step grading.  Make the vertical cut distance less than the horizontal distance, and slightly slope the horizontal position of the "step" in toward the vertical wall.  Do not make individual vertical cuts more than 2 ft. (0.6 m) high in soft materials or more than 3 ft. (0.9 m) high in rocky materials.
 Groove the slope using machinery to create a series of ridges and depressions that run across the slope, on the contour.

Fill Slope Roughening:
 Place on fill slopes with a gradient steeper than 3:1 in lifts not to exceed 8 in. (0.2 m), and make sure each lift is properly compacted.
 Ensure that the face of the slope consists of loose, uncompacted fill 4-6 in. (0.1-0.2 m) deep.  Use grooving or tracking to roughen the face of the slopes, if necessary.  Do not blade or scrape the final slope face.

Roughening for Slopes to be Mowed:
 Slopes that require mowing activities should not be steeper than 3:1.  Roughen these areas to shallow grooves by track walking, scarifying, sheepsfoot rolling, or imprinting.
 Make grooves close together (less than 10 in.), and not less than 1 in. deep, and perpendicular to the direction of runoff (i.e., parallel to the slope contours).  Excessive roughness is undesirable where mowing is planned.

Roughening with Tracked Machinery:
 Limit roughening with tracked machinery to soils with a sandy textural component to avoid undue compaction of the soil surface.
 Operate tracked machinery up and down the slope to leave horizontal depressions in the soil. Do not back-blade during the final grading operation.  Seed and mulch roughened areas as soon as possible to obtain optimum seed germination and growth.

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Costs
Costs are based on the additional labor of tracking or preparation of the slope plus the cost of any required soil amendment materials.

References
Soil Stabilization BMP Research for Erosion and Sediment Controls: Cost Survey Technical Memorandum, State of California Department of Transportation (Caltrans), July 2007.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

Silt Fence SE-1
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Description and Purpose
A silt fence is made of a woven geotextile that has been entrenched, attached to supporting poles, and sometimes backed by a plastic or wire mesh for support. The silt fence detains water, promoting sedimentation of coarse sediment behind the fence. Silt fence does not retain soil fine particles like clays or silts.

Suitable Applications
Silt fences are suitable for perimeter control, placed below areas where sheet flows discharge from the site. They could also be used as interior controls below disturbed areas where runoff may occur in the form of sheet and rill erosion and around inlets within disturbed areas (Storm Drain Inlet Protection, SE-10). Silt fences should not be used in locations where the flow is concentrated. Silt fences should always be used in combination with erosion controls. Suitable
applications include:
 At perimeter of a project (although they should not be installed up and down slopes).
 Below the toe or down slope of exposed and erodible slopes.  Along streams and channels.
 Around temporary spoil areas and stockpiles.
 Around inlets.
 Below other small cleared areas.

Categories
EC Erosion Control
SE Sediment Control 
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment (coarse sediment) 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
SE-5 Fiber Rolls
SE-6 Gravel Bag Berm SE-12 Manufactured Linear Sediment Controls SE-13 Compost Socks and Berms
SE-14 Biofilter Bags
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Silt Fence SE-1
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Limitations
 Do not use in streams, channels, drain inlets, or anywhere flow is concentrated.  Do not use in locations where ponded water may cause a flooding hazard.  Do not use silt fence to divert water flows or place across any contour line.  Improperly installed fences are subject to failure from undercutting, overtopping, or collapsing.
 Must be trenched and keyed in.
 According to the State Water Board’s CGP Review, Issue #2 (2014), silt fences reinforced with metal or plastic mesh should be avoided due to plastic pollution and wildlife concerns.  Not intended for use as a substitute for Fiber Rolls (SE-5), when fiber rolls are being used as a slope interruption device.
 Do not use on slopes subject to creeping, slumping, or landslides.

Implementation
General
A silt fence is a temporary sediment barrier consisting of woven geotextile stretched across and attached to supporting posts, trenched-in, and, depending upon the strength of fabric used, supported with plastic or wire mesh fence. Silt fences trap coarse sediment by intercepting and detaining sediment-laden runoff from disturbed areas in order to promote sedimentation behind the fence.

The following layout and installation guidance can improve performance and should be followed:
 Silt fence should be used in combination with erosion controls up-slope in order to provide the most effective sediment control.
 Silt fence alone is not effective at reducing turbidity. (Barrett and Malina, 2004)  Designers should consider diverting sediment laden water to a temporary sediment basin or trap. (EPA, 2012)
 Use principally in areas where sheet flow occurs.
 Install along a level contour, so water does not pond more than 1.5 ft. at any point along the silt fence.
 Provide sufficient room for runoff to pond behind the fence and to allow sediment removal equipment to pass between the silt fence and toes of slopes or other obstructions. About 1200 ft.2 of ponding area should be provided for every acre draining to the fence.  Efficiency of silt fences is primarily dependent on the detention time of the runoff behind the control. (Barrett and Malina, 2004)

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 The drainage area above any fence should not exceed a quarter of an acre. (Rule of Thumb- 100-feet of silt fence per 10,000 ft.2 of disturbed area.) (EPA, 2012)  The maximum length of slope draining to any point along the silt fence should be 100 ft. per ft of silt fence.
 Turn the ends of the filter fence uphill to prevent stormwater from flowing around the fence.  Leave an undisturbed or stabilized area immediately down slope from the fence where feasible.
 Silt fences should remain in place until the disturbed area draining to the silt fence is permanently stabilized, after which, the silt fence fabric and posts should be removed and properly disposed.
 J-hooks, which have ends turning up the slope to break up long runs of fence and provide multiple storage areas that work like mini-retention areas, may be used to increase the effectiveness of silt fence.
 Be aware of local regulations regarding the type and installation requirements of silt fence, which may differ from those presented in this fact sheet.

Design and Layout
In areas where high winds are anticipated the fence should be supported by a plastic or wire mesh. The geotextile fabric of the silt fence should contain ultraviolet inhibitors and stabilizers to provide longevity equivalent to the project life or replacement schedule.  Layout in accordance with the attached figures.
 For slopes that contain a high number of rocks or large dirt clods that tend to dislodge, it may be necessary to protect silt fence from rocks (e.g., rockfall netting) ensure the integrity of the silt fence installation.

Standard vs. Heavy Duty Silt Fence
Standard Silt Fence
 Generally applicable in cases where the area draining to fence produces moderate sediment loads.

Heavy Duty Silt Fence
 Heavy duty silt fence usually has 1 or more of the following characteristics, not possessed by standard silt fence.
o Fabric is reinforced with wire backing or additional support. o Posts are spaced closer than pre-manufactured, standard silt fence products.  Use is generally limited to areas affected by high winds.  Area draining to fence produces moderate sediment loads.

Materials
Standard Silt Fence
 Silt fence material should be woven geotextile with a minimum width of 36 in. The fabric should conform to the requirements in ASTM designation D6461.

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 Wooden stakes should be commercial quality lumber of the size and shape shown on the plans. Each stake should be free from decay, splits or cracks longer than the thickness of the stake or other defects that would weaken the stakes and cause the stakes to be structurally unsuitable.
 Staples used to fasten the fence fabric to the stakes should be not less than 1.75 in. long and should be fabricated from 15-gauge or heavier wire. The wire used to fasten the tops of the stakes together when joining two sections of fence should be 9 gauge or heavier wire. Galvanizing of the fastening wire will not be required.

Heavy-Duty Silt Fence
 Some silt fence has a wire backing to provide additional support, and there are products that may use prefabricated plastic holders for the silt fence and use metal posts instead of wood stakes.

Installation Guidelines – Traditional Method
Silt fences are to be constructed on a level contour. Sufficient area should exist behind the fence for ponding to occur without flooding or overtopping the fence.  A trench should be excavated approximately 6 in. wide and 6 in. deep along the line of the proposed silt fence (trenches should not be excavated wider or deeper than necessary for proper silt fence installation).
 Bottom of the silt fence should be keyed-in a minimum of 12 in.  Posts should be spaced a maximum of 6 ft. apart and driven securely into the ground a minimum of 18 in. or 12 in. below the bottom of the trench.  When standard strength geotextile is used, a plastic or wire mesh support fence should be fastened securely to the upslope side of posts using heavy–duty wire staples at least 1 in. long. The mesh should extend into the trench.
 When extra-strength geotextile and closer post spacing are used, the mesh support fence may be eliminated.
 Woven geotextile should be purchased in a long roll, then cut to the length of the barrier.

When joints are necessary, geotextile should be spliced together only at a support post, with a minimum 6 in. overlap and both ends securely fastened to the post.  The trench should be backfilled with native material and compacted.  Construct the length of each reach so that the change in base elevation along the reach does not exceed 1/3 the height of the barrier; in no case should the reach exceed 500 ft.  Cross barriers should be a minimum of 1/3 and a maximum of ½ the height of the linear barrier.
 See typical installation details at the end of this fact sheet.

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Installation Guidelines - Static Slicing Method
 Static Slicing is defined as insertion of a narrow blade pulled behind a tractor, similar to a plow blade, at least 10 in. into the soil while at the same time pulling silt geotextile fabric into the ground through the opening created by the blade to the depth of the blade. Once the geotextile is installed, the soil is compacted using tractor tires.  This method will not work with pre-fabricated, wire backed silt fence.  Benefits:
o Ease of installation (most often done with a 2-person crew). o Minimal soil disturbance.
o Better level of compaction along fence, less susceptible to undercutting o Uniform installation.
 Limitations:
o Does not work in shallow or rocky soils.
o Complete removal of geotextile material after use is difficult. o Be cautious when digging near potential underground utilities.

Costs
 It should be noted that costs vary greatly across regions due to available supplies and labor costs.
 Average annual cost for installation using the traditional silt fence installation method (assumes 6 month useful life) is $7 per linear foot based on vendor research. Range of cost is $3.50 - $9.10 per linear foot.

Inspection and Maintenance
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Repair undercut silt fences.
 Repair or replace split, torn, slumping, or weathered fabric. The lifespan of silt fence fabric is generally 5 to 8 months.
 Silt fences that are damaged and become unsuitable for the intended purpose should be removed from the site of work, disposed, and replaced with new silt fence barriers.  Sediment that accumulates in the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches 1/3 of the barrier height.

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 Silt fences should be left in place until the upgradient area is permanently stabilized. Until then, the silt fence should be inspected and maintained regularly.  Remove silt fence when upgradient areas are stabilized. Fill and compact post holes and anchor trench, remove sediment accumulation, grade fence alignment to blend with adjacent ground, and stabilize disturbed area.

References
CGP Review #2, State Water Resources Control Board, 2014. Available online at:
http://www.waterboards.ca.gov/water_issues/programs/stormwater/docs/training/cgp_revie w_issue2.pdf.

Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

Monitoring Data on Effectiveness of Sediment Control Techniques, Proceedings of World Water and Environmental Resources Congress, Barrett M. and Malina J. 2004.

National Management Measures to Control Nonpoint Source Pollution from Urban Areas, United States Environmental Protection Agency, 2002.

Proposed Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters, Work Group-Working Paper, USEPA, April 1992.

Sedimentation and Erosion Control Practices, and Inventory of Current Practices (Draft), USEPA, 1990.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Management Manual for The Puget Sound Basin, Washington State Department of Ecology, Public Review Draft, 1991.

U.S. Environmental Protection Agency (USEPA). Stormwater Best Management Practices: Silt Fences. U.S. Environmental Protection Agency, Office of Water, Washington, DC, 2012.

U.S. Environmental Protection Agency (USEPA). Stormwater Management for Industrial Activities: Developing Pollution Prevention Plans and Best Management Practices. U.S.

Environmental Protection Agency, Office of Water, Washington, DC, 1992.

Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988.

Soil Stabilization BMP Research for Erosion and Sediment Controls: Cost Survey Technical Memorandum, State of California Department of Transportation (Caltrans), July 2007.

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Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

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Sediment Basin SE-2
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Description and Purpose
A sediment basin is a temporary basin formed by excavation or by constructing an embankment so that sediment-laden runoff is temporarily detained under quiescent conditions, allowing sediment to settle out before the runoff is released.

Sediment basin design guidance presented in this fact sheet is intended to provide options, methods, and techniques to optimize temporary sediment basin performance and basin sediment removal. Basin design guidance provided in this fact sheet is not intended to guarantee basin effluent compliance with numeric discharge limits (numeric action levels or numeric effluent limits for turbidity). Compliance with discharge limits requires a thoughtful approach to comprehensive BMP
planning, implementation, and maintenance. Therefore,
optimally designed and maintained sediment basins should be used in conjunction with a comprehensive system of BMPs that includes:
 Diverting runoff from undisturbed areas away from the basin
 Erosion control practices to minimize disturbed areas on- site and to provide temporary stabilization and interim sediment controls (e.g., stockpile perimeter control, check dams, perimeter controls around individual lots) to reduce the basin’s influent sediment concentration.

At some sites, sediment basin design enhancements may be required to adequately remove sediment. Traditional
Categories
EC Erosion Control SE Sediment Control  TC Tracking Control WE Wind Erosion Control NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment  Nutrients
Trash  Metals Bacteria Oil and Grease Organics

Potential Alternatives
SE-3 Sediment Trap (for smaller areas)
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(a.k.a. “physical”) enhancements such as alternative outlet configurations or flow deflection baffles increase detention time and other techniques such as outlet skimmers preferentially drain flows with lower sediment concentrations. These “physical” enhancement techniques are described in this fact sheet. To further enhance sediment removal particularly at sites with fine soils or turbidity sensitive receiving waters, some projects may need to consider implementing Active Treatment Systems (ATS) whereby coagulants and flocculants are used to enhance settling and removal of suspended sediments. Guidance on implementing ATS is provided in SE-11.

Suitable Applications
Sediment basins may be suitable for use on larger projects with sufficient space for constructing the basin. Sediment basins should be considered for use:
 Where sediment-laden water may enter the drainage system or watercourses  On construction projects with disturbed areas during the rainy season  At the outlet of disturbed watersheds between 5 acres and 75 acres and evaluated on a site by site basis
 Where post construction detention basins are required  In association with dikes, temporary channels, and pipes used to convey runoff from disturbed areas
Limitations
Sediment basins must be installed only within the property limits and where failure of the structure will not result in loss of life, damage to homes or buildings, or interruption of use or service of public roads or utilities. In addition, sediment basins are attractive to children and can be very dangerous. Local ordinances regarding health and safety must be adhered to. If fencing of the basin is required, the type of fence and its location should be shown in the SWPPP and in the construction specifications.
 As a general guideline, sediment basins are suitable for drainage areas of 5 acres or more, but not appropriate for drainage areas greater than 75 acres. However, the tributary area should be evaluated on a site by site basis.
 Sediment basins may become an “attractive nuisance” and care must be taken to adhere to all safety practices. If safety is a concern, basin may require protective fencing.  Sediment basins designed according to this fact sheet are only effective in removing sediment down to about the silt size fraction. Sediment-laden runoff with smaller size fractions (fine silt and clay) may not be adequately treated unless chemical (or other appropriate method) treatment is used in addition to the sediment basin.  Basins with a height of 25 ft or more or an impounding capacity of 50 ac-ft or more must obtain approval from California Department of Water Resources Division of Safety of Dams ( http://www.water.ca.gov/damsafety/) .

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 Water that stands in sediment basins longer than 96 hours may become a source of mosquitoes (and midges), particularly along perimeter edges, in shallow zones, in scour or below-grade pools, around inlet pipes, along low-flow channels, and among protected habitats created by emergent or floating vegetation (e.g. cattails, water hyacinth), algal mats, riprap, etc.
 Basins require large surface areas to permit settling of sediment. Size may be limited by the available area.

Implementation
General
A sediment basin is a controlled stormwater release structure formed by excavation or by construction of an embankment of compacted soil across a drainage way, or other suitable location. It is intended to trap sediment before it leaves the construction site. The basin is a temporary measure expected to be used during active construction in most cases and is to be maintained until the site area is permanently protected against erosion or a permanent detention basin is constructed.

Sediment basins are suitable for nearly all types of construction projects. Whenever possible, construct the sediment basins before clearing and grading work begins. Basins should be located at the stormwater outlet from the site but not in any natural or undisturbed stream. A typical application would include temporary dikes, pipes, and/or channels to convey runoff to the basin inlet.

Many development projects in California are required by local ordinances to provide a stormwater detention basin for post-construction flood control, desilting, or stormwater pollution control. A temporary sediment basin may be constructed by rough grading the post- construction control basins early in the project.

Sediment basins if properly designed and maintained can trap a significant amount of the sediment that flows into them. However, traditional basins do not remove all inflowing sediment. Therefore, they should be used in conjunction with erosion control practices such as temporary seeding, mulching, diversion dikes, etc., to reduce the amount of sediment flowing into the basin.

Planning
To improve the effectiveness of the basin, it should be located to intercept runoff from the largest possible amount of disturbed area. Locations best suited for a sediment basin are generally in lower elevation areas of the site (or basin tributary area) where site drainage would not require significant diversion or other means to direct water to the basin but outside jurisdictional waterways. However, as necessary, drainage into the basin can be improved by the use of earth dikes and drainage swales (see BMP EC-9). . The basin should not be located where its failure would result in the loss of life or interruption of the use or service of public utilities or roads.

Construct before clearing and grading work begins when feasible.  Do not locate the basin in a jurisdictional stream.

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 Basin sites should be located where failure of the structure will not cause loss of life, damage to homes or buildings, or interruption of use or service of public roads or utilities.  Basins with a height of 25 ft or more or an impounding capacity of 50 ac-ft must obtain approval from the Division of Dam Safety. Local dam safety requirements may be more stringent.
 Limit the contributing area to the sediment basin to only the runoff from the disturbed soil areas. Use temporary concentrated flow conveyance controls to divert runoff from undisturbed areas away from the sediment basin.
 The basin should be located: (1) by excavating a suitable area or where a low embankment can be constructed across a swale, (2) where post-construction (permanent) detention basins will be constructed, and (3) where the basins can be maintained on a year-round basis to provide access for maintenance, including sediment removal and sediment stockpiling in a protected area, and to maintain the basin to provide the required capacity.

Design
When designing a sediment basin, designers should evaluate the site constraints that could affect the efficiency of the BMP. Some of these constraints include: the relationship between basin capacity, anticipated sediment load, and freeboard, available footprint for the basin, maintenance frequency and access, and hydraulic capacity and efficiency of the temporary outlet infrastructure. Sediment basins should be designed to maximize sediment removal and to consider sediment load retained by the basin as it affects basin performance.

Three Basin Design Options (Part A) are presented below along with a Typical Sediment/Detention Basin Design Methodology (Part B). Regardless of the design option that is selected, designers also need to evaluate the sediment basin capacity with respect to sediment accumulation (See “Step 3. Evaluate the Capacity of the Sediment Basin”) and should incorporate approaches identified in “Step 4. Other Design Considerations” to enhance basin performance.

A) Basin Design Options:

Option 1:

Design sediment basin(s) using the standard equation:
s
s V
QA2.1= (Eq. 1)
Where:

As = Minimum surface area for trapping soil particles of a certain size Vs = Settling velocity of the design particle size chosen (Vs = 0.00028 ft/s for a design particle size of 0.01 mm at 68°F)

1.2 = Factor of safety recommended by USEPA to account for the reduction in basin efficiency caused due to turbulence and other non ideal conditions.

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CIAQ= (Eq.2)
Where
Q = Peak basin influent flow rate measured in cubic feet per second (ft3/s) C = Runoff coefficient (unitless)
I = Peak rainfall intensity for the 10-year, 6-hour rain event (in/hr) A = Area draining into the sediment basin in acres
The design particle size should be the smallest soil grain size determined by wet sieve analysis, or the fine silt sized (0.01 mm [or 0.0004 in.]) particle, and the Vs used should be 100 percent of the calculated settling velocity.

This sizing basin method is dependent on the outlet structure design or the total basin length with an appropriate outlet. If the designer chooses to utilize the outlet structure to control the flow duration in the basin, the basin length (distance between the inlet and the outlet) should be a minimum of twice the basin width; the depth should not be less than 3 ft nor greater than 5 ft for safety reasons and for maximum efficiency (2 ft of sediment storage, 2 ft of capacity). If the designer chooses to utilize the basin length (with appropriate basin outlet) to control the flow duration in the basin, the basin length (distance between the inlet and the outlet) should be a specifically designed to capture 100% of the design particle size; the depth should not be less than 3 ft nor greater than 5 ft for safety reasons and for maximum efficiency (2 ft of sediment storage, 2 ft of capacity).

Basin design guidance provided herein assumes standard water properties (e.g., estimated average water temperature, kinematic viscosity, etc.) as a basis of the design.

Designers can use an alternative design (Option 3) with site specific water properties as long as the design is as protective as Option 1.

The design guidance uses the peak influent flow rate to size sediment basins. Designers can use an alternative design (Option 3) with site specific average flow rates as long as the design is as protective as Option 1.

The basin should be located on the site where it can be maintained on a year-round basis and should be maintained on a schedule to retain the 2 ft of capacity.

Option 2:

Design pursuant to local ordinance for sediment basin design and maintenance, provided that the design efficiency is as protective or more protective of water quality than Option 1.

Option 3:

The use of an equivalent surface area design or equation provided that the design efficiency is as protective or more protective of water quality than Option 1.

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B) Typical Sediment/Detention Basin Design Methodology:

Design of a sediment basin requires the designer to have an understanding of the site constraints, knowledge of the local soil (e.g., particle size distribution of potentially contributing soils), drainage area of the basin, and local hydrology. Designers should not assume that a sediment basin for location A is applicable to location B. Therefore, designers can use this factsheet as guidance but will need to apply professional judgment and knowledge of the site to design an effective and efficient sediment basin. The following provides a general overview of typical design methodologies:

Step 1. Hydrologic Design
 Evaluate the site constraints and assess the drainage area for the sediment basin. Designers should consider on- and off-site flows as well as changes in the drainage area associated with site construction/disturbance. To minimize additional construction during the course of the project, the designer should consider identifying the maximum drainage area when calculating the basin dimensions.
 If a local hydrology manual is not available, it is recommended to follow standard rational method procedures to estimate the flow rate. The references section of this factsheet provides a reference to standard hydrology textbooks that can provide standard methodologies. If local rainfall depths are not available, values can be obtained from standard precipitation frequency maps from NOAA (downloaded from http://www.wrcc.dri.edu/pcpnfreq.html) .

Step 2. Hydraulic Design
 Calculate the surface area required for the sediment basin using Equation 1. In which the flow rate is estimated for a 10-yr 6-hr event using rational method procedure listed in local hydrology manual and Vs is estimated using Stokes Law presented in Equation 3. 281.2 dVs= (Eq.3)
Where
Vs = Settling velocity in feet per second at 68˚F
d = diameter of sediment particle in millimeters (smallest soil grain size determined by wet sieve analysis or fine silt (0.01 mm [or 0.0004 in.])  In general, the basin outlet design requires an iterative trial and error approach that considered the maximum water surface elevation, the elevation versus volume (stage- storage) relationship, the elevation verses basin outflow (a.k.a.-discharge) relationship, and the estimated inflow hydrograph. To adequately design the basins to settle sediment, the outlet configuration and associated outflow rates can be estimated by numerous methodologies. The following provides some guidance for design the basin outlet:
 An outlet should have more than one orifice.
 An outlet design typically utilizes multiple horizontal rows of orifices (approximately 3 or more) with at least 2 orifices per row (see Figures 1 and 2 at the end of this fact sheet).

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 Orifices can vary in shape.
 Select the appropriate orifice diameter and number of perforations per row with the objective of minimizing the number of rows while maximizing the detention time.  The diameter of each orifice is typically a maximum of 3-4 inches and a minimum of

0.25-0.5 inches.
 If a rectangular orifice is used, it is recommended to have minimum height of 0.5 inches and a maximum height of 6 inches.
 Rows are typically spaced at three times the diameter center to center vertically with a minimum distance of approximately 4 inches on center and a maximum distance of 1 foot on center.
 To estimate the outflow rate, each row is calculated separately based on the flow through a single orifice then multiplied by the number of orifices in the row. This step is repeated for each of the rows. Once all of the orifices are estimated, the total outflow rate versus elevation (stage-discharge curve) is developed to evaluate the detention time within the basin.
 Flow through a single orifice can be estimated using an Equation 4:

5.0)2('gHABCQ= (Eq.4)
Where Q = Outflow rate in ft3/s C΄ = Orifice coefficient (unitless) A = Area of the orifice (ft2) g = acceleration due to gravity (ft3/s)
H = Head above the orifice (ft) B = Anticipated Blockage or clogging factor (unitless), It is dependent on anticipated sediment and debris load, trash rack configuration etc, so the value is dependent on design engineer’s professional judgment and/or local requirements (B is never greater than 1 and a value of 0.5 is generally used)

 Care must be taken in the selection of orifice coefficient ("C΄"); 0.60 is most often recommended and used. However, based on actual tests, Young and Graziano (1989), "Outlet Hydraulics of Extended Detention Facilities for Northern Virginia Planning District Commission", recommends the following:
 C΄ = 0.66 for thin materials; where the thickness is equal to or less than the orifice diameter, or
 C΄ = 0.80 when the material is thicker than the orifice diameter  If different sizes of orifices are used along the riser then they have to be sized such that not more than 50 percent of the design storm event drains in one-third of the drawdown time (to provide adequate settling time for events smaller than the design storm event)

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and the entire volume drains within 96 hours or as regulated by the local vector control agency. If a basin fails to drain within 96 hours, the basin must be pumped dry.  Because basins are not maintained for infiltration, water loss by infiltration should be disregarded when designing the hydraulic capacity of the outlet structure.  Floating Outlet Skimmer: The floating skimmer (see Figure 3 at the end of this fact sheet is an alternative outlet configuration (patented) that drains water from upper portion of the water column. This configuration has been used for temporary and permanent basins and can improve basin performance by eliminating bottom orifices which have the potential of discharging solids. Some design considerations for this alternative outlet device includes the addition of a sand filter or perforated under drain at the low point in the basin and near the floating skimmer. These secondary drains allow the basin to fully drain. More detailed guidelines for sizing the skimmer can be downloaded from http://www.fairclothskimmer.com/ .
 Hold and Release Valve: An ideal sediment/detention basin would hold all flows to the design storm level for sufficient time to settle solids, and then slowly release the storm water. Implementing a reliable valve system for releasing detention basins is critical to eliminate the potential for flooding in such a system. Some variations of hold and release valves include manual valves, bladder devices or electrically operated valves. When a precipitation event is forecast, the valve would be close for the duration of the storm and appropriate settling time. When the settling duration is met (approximately 24 or 48 hours), the valve would be opened and allow the stormwater to be released at a rate that does not resuspend settled solids and in a non-erosive manner. If this type of system is used the valve should be designed to empty the entire basin within 96 hours or as stipulated by local vector control regulations.

Step 3. Evaluate the Capacity of the Sediment Basin
 Typically, sediment basins do not perform as designed when they are not properly maintained or the sediment yield to the basin is larger than expected. As part of a good sediment basin design, designers should consider maintenance cycles, estimated soil loss and/or sediment yield, and basin sediment storage volume. The two equations below can be used to quantify the amount of soil entering the basin.  The Revised Universal Soil Loss Equation (RUSLE, Eq.5) can be used to estimate annual soil loss and the Modified Universal Soil Equation (MUSLE, Eq.6) can be used to estimate sediment yield from a single storm event.

PCLSKRA××××= (Eq.5)
( )PCLSKqQYp×××××=56.095 (Eq.6)
Where:

A = annual soil loss, tons/acre-year
R = rainfall erosion index, in 100 ft. Tons/acre.in/hr.

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K = soil erodibility factor, tons/acre per unit of R
LS = slope length and steepness factor (unitless)
C = vegetative cover factor (unitless)
P = erosion control practice factor (unitless)
Y = single storm sediment yield in tons
Q = runoff volume in acre-feet
qp = peak flow in cfs
 Detailed descriptions and methodologies for estimating the soil loss can be obtained from standard hydrology text books (See References section).  Determination of the appropriate equation should consider construction duration and local environmental factors (soils, hydrology, etc.). For example, if a basin is planned for a project duration of 1 year and the designer specifies one maintenance cycle, RUSLE could be used to estimate the soil loss and thereby the designer could indicate that the sediment storage volume would be half of the soil loss value estimated. As an example, for use of MUSLE, a project may have a short construction duration thereby requiring fewer maintenance cycles and a reduced sediment storage volume. MUSLE would be used to estimate the anticipated soil loss based on a specific storm event to evaluate the sediment storage volume and appropriate maintenance frequency.
 The soil loss estimates are an essential step in the design, and it is essential that the designer provide construction contractors with enough information to understand maintenance frequency and/or depths within the basin that would trigger maintenance. Providing maintenance methods, frequency and specification should be included in design bid documents such as the SWPPP Site Map.
 Once the designer has quantified the amount of soil entering the basin, the depth required for sediment storage can be determined by dividing the estimated sediment loss by the surface area of the basin.

Step 4. Other Design Considerations
 Consider designing the volume of the settling zone for the total storm volume associated with the 2-year event or other appropriate design storms specified by the local agency. This volume can be used as a guide for sizing the basin without iterative routing calculations. The depth of the settling zone can be estimated by dividing the estimated 2-yr storm volume by the surface area of the basin.
 The basin volume consists of two zones:
A sediment storage zone at least 1 ft deep.
A settling zone at least 2 ft deep.

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The basin depth must be no less than 3 ft (not including freeboard).  Proper hydraulic design of the outlet is critical to achieving the desired performance of the basin. The outlet should be designed to drain the basin within 24 to 96 hours (also referred to as “drawdown time”). The 24-hour limit is specified to provide adequate settling time; the 96-hour limit is specified to mitigate vector control concerns.  Confirmation of the basin performance can be evaluated by routing the design storm (10-yr 6-hr, or as directed by local regulations) through the basin based on the basin volume (stage- storage curve) and the outlet design (stage-discharge curve based on the orifice configuration or equivalent outlet design).
 Sediment basins, regardless of size and storage volume, should include features to accommodate overflow or bypass flows that exceed the design storm event. Include an emergency spillway to accommodate flows not carried by the principal spillway. The spillway should consist of an open channel (earthen or vegetated) over undisturbed material (not fill) or constructed of a non-erodible riprap (or equivalent protection) on fill slopes.
The spillway control section, which is a level portion of the spillway channel at the highest elevation in the channel, should be a minimum of 20 ft in length.  Rock, vegetation or appropriate erosion control should be used to protect the basin inlet, outlet, and slopes against erosion.
 The total depth of the sediment basin should include the depth required for sediment storage, depth required for settling zone and freeboard of at least 1 foot or as regulated by local flood control agency for a flood event specified by the local agency.  The basin alignment should be designed such that the length of the basin is more than twice the width of the basin; the length should be determined by measuring the distance between the inlet and the outlet. If the site topography does not allow for this configuration baffles should be installed so that the ratio is satisfied. If a basin has more than one inflow point, any inflow point that conveys more than 30 percent of the total peak inflow rate has to meet the required length to width ratio.
 An alternative basin sizing method proposed by Fifield (2004) can be consulted to estimate an alternative length to width ratio and basin configuration. These methods can be considered as part of Option 3 which allows for alternative designs that are protective or more protective of water quality.
 Baffles (see Figure 4 at the end of this fact sheet) can be considered at project sites where the existing topography or site constraints limit the length to width ratio. Baffles should be constructed of earthen berms or other structural material within the basin to divert flow in the basin, thus increasing the effective flow length from the basin inlet to the outlet riser.

Baffles also reduce the change of short circuiting and allows for settling throughout the basin.

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 Baffles are typically constructed from the invert of the basin to the crest of the emergency spillway (i.e., design event flows are meant to flow around the baffles and flows greater than the design event would flow over the baffles to the emergency spillway).  Use of other materials for construction of basin baffles (such as silt fence) may not be appropriate based on the material specifications and will require frequent maintenance (maintain after every storm event). Maintenance may not be feasible when required due to flooded conditions resulting from frequent (i.e., back to back) storm events. Use of alternative baffle materials should not deviate from the intended purpose of the material, as described by the manufacturer.
 Sediment basins are best used in conjunction with erosion controls.  Basins with an impounding levee greater than 4.5 ft tall, measured from the lowest point to the impounding area to the highest point of the levee, and basins capable of impounding more than 35,000 ft3, should be designed by a Registered Civil Engineer. The design should include maintenance requirements, including sediment and vegetation removal, to ensure continuous function of the basin outlet and bypass structures.  A forebay, constructed upstream of the basin, may be provided to remove debris and larger particles.
 The outflow from the sediment basin should be provided with velocity dissipation devices (see BMP EC-10) to prevent erosion and scouring of the embankment and channel.  The principal outlet should consist of a corrugated metal, high density polyethylene (HDPE), or reinforced concrete riser pipe with dewatering holes and an anti-vortex device and trash rack attached to the top of the riser, to prevent floating debris from flowing out of the basin or obstructing the system. This principal structure should be designed to accommodate the inflow design storm.
 A rock pile or rock-filled gabions can serve as alternatives to the debris screen, although the designer should be aware of the potential for extra maintenance involved should the pore spaces in the rock pile clog.
 The outlet structure should be placed on a firm, smooth foundation with the base securely anchored with concrete or other means to prevent floatation.  Attach riser pipe (watertight connection) to a horizontal pipe (barrel). Provide anti-seep collars on the barrel.
 Cleanout level should be clearly marked on the riser pipe.

Installation
 Securely anchor and install an anti-seep collar on the outlet pipe/riser and provide an emergency spillway for passing major floods (see local flood control agency).  Areas under embankments must be cleared and stripped of vegetation.

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 Chain link fencing should be provided around each sediment basin to prevent unauthorized entry to the basin or if safety is a concern.

Costs
The cost of a sediment basin is highly variable and is dependent of the site configuration. To decrease basin construction costs, designers should consider using existing site features such as berms or depressed area to site the sediment basin. Designers should also consider potential savings associated with designing the basin to minimize the number of maintenance cycles and siting the basin in a location where a permanent BMP (e.g., extended detention basin) is required for the project site.

Inspection and Maintenance
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level and as required by local requirements. It is recommended that at a minimum, basins be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.  Examine basin banks for seepage and structural soundness.  Check inlet and outlet structures and spillway for any damage or obstructions. Repair damage and remove obstructions as needed.
 Check inlet and outlet area for erosion and stabilize if required.  Check fencing for damage and repair as needed.
 Sediment that accumulates in the basin must be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when sediment accumulation reaches one- half the designated sediment storage volume. Sediment removed during maintenance should be managed properly. The sediment should be appropriately evaluated and used or disposed of accordingly. Options include: incorporating sediment into earthwork on the site (only if there is no risk that sediment is contaminated); or off-site export/disposal at an appropriate location (e.g., sediment characterization and disposal to an appropriate landfill).  Remove standing water from basin within 96 hours after accumulation.  If the basin does not drain adequately (e.g., due to storms that are more frequent or larger than the design storm or other unforeseen site conditions), dewatering should be conducted in accordance with appropriate dewatering BMPs (see NS-2) and in accordance with local permits as applicable.
 To minimize vector production:
Remove accumulation of live and dead floating vegetation in basins during every inspection.
Remove excessive emergent and perimeter vegetation as needed or as advised by local or state vector control agencies.

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References
A Current Assessment of Urban Best Management Practices: Techniques for Reducing Nonpoint Source Pollution in the Coastal Zones, Metropolitan Washington Council of Governments, March 1992.

Draft-Sedimentation and Erosion Control, an Inventory of Current Practices, USEPA. April 1990.

U.S. Environmental Protection Agency (USEPA). Erosion and Sediment Control, Surface Mining in the Eastern U.S., U.S. Environmental Protection Agency, Office of Water, Washington, DC,Washington, D.C., 1976.

Fifield, J.S. Designing for Effective Sediment and Erosion Control on Construction Sites.

Forester Press, Santa Barbara, CA. 2004.

Goldman S.J., Jackson K. and Bursztynsky T.A. Erosion and Sediment Control Handbook.

McGraw-Hill Book Company, 1986.

U.S. Environmental Protection Agency (USEPA). Guidance Specifying Management Measures for Nonpoint Pollution in Coastal Waters. EPA 840-B-9-002. U.S. Environmental Protection Agency, Office of Water, Washington, DC, 1993.

Guidelines for the Design and Construction of Small Embankment Dams, Division of Safety of Dams, California Department of Water Resources, March 1986.

Haan C.T., Barfield B.J. and Hayes J.C. Design Hydrology and Sedimentology for Small Catchments. Academic Press. 1994.

Inlet/Outlet Alternatives for Extended Detention Basins. State of California Department of Transportation (Caltrans), 2001.

Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

McLean, J., 2000. Mosquitoes in Constructed Wetlands: A Management Bugaboo? In T.R.

Schueler and H.K. Holland [eds.], The Practice of Watershed Protection. pp. 29-33. Center for Watershed Protection, Ellicott City, MD, 2000.

Metzger, M.E., D. F. Messer, C. L. Beitia, C. M. Myers, and V. L. Kramer. The Dark Side of Stormwater Runoff Management: Disease Vectors Associated with Structural BMPs, 2002.

National Management Measures to Control Nonpoint Source Pollution from Urban Areas, United States Environmental Protection Agency, 2002.

Proposed Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Water, Work Group-Working Paper, USEPA, April 1992.

Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992.

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Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Water Quality Management Plan for the Lake Tahoe Region, Volume II Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988.

Young, G.K. and Graziano, F., Outlet Hydraulics of Extended Detention Facilities for Northern Virginia Planning District Commission, 1989.

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FIGURE 1: TYPICAL TEMPORARY SEDIMENT BASIN

MULTIPLE ORIFICE DESIGN

NOT TO SCALE

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FIGURE 2: MULTIPLE ORIFICE OUTLET RISER

NOT TO SCALE

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FIGURE 3: TYPICAL SKIMMER

NOT TO SCALE

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FIGURE 4: TYPICAL TEMPORARY SEDIMENT BASIN

WITH BAFFLES

NOT TO SCALE

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Description and Purpose
A check dam is a small barrier constructed of rock, gravel bags, sandbags, fiber rolls, or other proprietary products, placed across a constructed swale or drainage ditch. Check dams reduce the effective slope of the channel, thereby reducing scour and channel erosion by reducing flow velocity and increasing residence time within the channel, allowing
sediment to settle.

Suitable Applications
Check dams may be appropriate in the following situations:
 To promote sedimentation behind the dam.
 To prevent erosion by reducing the velocity of channel flow in small intermittent channels and temporary swales.
 In small open channels that drain 10 acres or less.
 In steep channels where stormwater runoff velocities
exceed 5 ft/s.
 During the establishment of grass linings in drainage ditches or channels.
 In temporary ditches where the short length of service does not warrant establishment of erosion-resistant linings.  To act as a grade control structure.

Categories
EC Erosion Control 
SE Sediment Control 
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
SE-5 Fiber Rolls
SE-6 Gravel Bag Berm
SE-8 Sandbag Barrier
SE-12 Manufactured Linear Sediment Controls
SE-14 Biofilter Bags
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Limitations
 Not to be used in live streams or in channels with extended base flows.  Not appropriate in channels that drain areas greater than 10 acres.  Not appropriate in channels that are already grass-lined unless erosion potential or sediment-laden flow is expected, as installation may damage vegetation.  Require extensive maintenance following high velocity flows.  Promotes sediment trapping which can be re-suspended during subsequent storms or removal of the check dam.
 Do not construct check dams with straw bales or silt fence.  Water suitable for mosquito production may stand behind check dams, particularly if subjected to daily non-stormwater discharges.

Implementation
General
Check dams reduce the effective slope and create small pools in swales and ditches that drain 10 acres or less. Using check dams to reduce channel slope reduces the velocity of stormwater flows, thus reducing erosion of the swale or ditch and promoting sedimentation. Thus, check dams are dual-purpose and serve an important role as erosion controls as well as sediment controls. Note that use of 1-2 isolated check dams for sedimentation will likely result in little net removal of sediment because of the small detention time and probable scour during longer storms. Using a series of check dams will generally increase their effectiveness. A sediment trap (SE-3) may be placed immediately upstream of the check dam to increase sediment removal efficiency.

Design and Layout
Check dams work by decreasing the effective slope in ditches and swales. An important consequence of the reduced slope is a reduction in capacity of the ditch or swale. This reduction in capacity should be considered when using this BMP, as reduced capacity can result in overtopping of the ditch or swale and resultant consequences. In some cases, such as a “permanent” ditch or swale being constructed early and used as a “temporary” conveyance for construction flows, the ditch or swale may have sufficient capacity such that the temporary reduction in capacity due to check dams is acceptable. When check dams reduce capacities beyond acceptable limits, either:
 Don’t use check dams. Consider alternative BMPs, or.  Increase the size of the ditch or swale to restore capacity.

Maximum slope and velocity reduction is achieved when the toe of the upstream dam is at the same elevation as the top of the downstream dam (see “Spacing Between Check Dams” detail at the end of this fact sheet). The center section of the dam should be lower than the edge sections (at least 6 inches), acting as a spillway, so that the check dam will direct flows to the center of

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the ditch or swale (see “Typical Rock Check Dam” detail at the end of this fact sheet). Bypass or side-cutting can occur if a sufficient spillway is not provided in the center of the dam.

Check dams are usually constructed of rock, gravel bags, sandbags, and fiber rolls. A number of products can also be used as check dams (e.g. HDPE check dams, temporary silt dikes (SE-12)), and some of these products can be removed and reused. Check dams can also be constructed of logs or lumber and have the advantage of a longer lifespan when compared to gravel bags, sandbags, and fiber rolls. Check dams should not be constructed from straw bales or silt fences, since concentrated flows quickly wash out these materials.

Rock check dams are usually constructed of 8 to 12 in. rock. The rock is placed either by hand or mechanically, but never just dumped into the channel. The dam should completely span the ditch or swale to prevent washout. The rock used should be large enough to stay in place given the expected design flow through the channel. It is recommended that abutments be extended 18 in. into the channel bank. Rock can be graded such that smaller diameter rock (e.g. 2-4 in) is located on the upstream side of larger rock (holding the smaller rock in place); increasing residence time.

Log check dams are usually constructed of 4 to 6 in. diameter logs, installed vertically. The logs should be embedded into the soil at least 18 in. Logs can be bolted or wired to vertical support logs that have been driven or buried into the soil.

See fiber rolls, SE-5, for installation of fiber roll check dams.

Gravel bag and sand bag check dams are constructed by stacking bags across the ditch or swale, shaped as shown in the drawings at the end of this fact sheet (see “Gravel Bag Check Dam” detail at the end of this fact sheet).

Manufactured products, such as temporary silt dikes (SE-12), should be installed in accordance with the manufacturer’s instructions. Installation typically requires anchoring or trenching of products, as well as regular maintenance to remove accumulated sediment and debris.

If grass is planted to stabilize the ditch or swale, the check dam should be removed when the grass has matured (unless the slope of the swales is greater than 4%).

The following guidance should be followed for the design and layout of check dams:
 Install the first check dam approximately 16 ft from the outfall device and at regular intervals based on slope gradient and soil type.
 Check dams should be placed at a distance and height to allow small pools to form between each check dam.
 For multiple check dam installation, backwater from a downstream check dam should reach the toes of the upstream check dam.
 A sediment trap provided immediately upstream of the check dam will help capture sediment. Due to the potential for this sediment to be resuspended in subsequent storms, the sediment trap should be cleaned following each storm event.

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 High flows (typically a 2-year storm or larger) should safely flow over the check dam without an increase in upstream flooding or damage to the check dam.  Where grass is used to line ditches, check dams should be removed when grass has matured sufficiently to protect the ditch or swale.

Materials
 Rock used for check dams should typically be 8-12 in rock and be sufficiently sized to stay in place given expected design flows in the channel. Smaller diameter rock (e.g. 2 to 4 in) can be placed on the upstream side of larger rock to increase residence time.  Gravel bags used for check dams should conform to the requirements of SE-6, Gravel Bag Berms.
 Sandbags used for check dams should conform to SE-8, Sandbag Barrier.  Fiber rolls used for check dams should conform to SE-5, Fiber Rolls.  Temporary silt dikes used for check dams should conform to SE-12, Temporary Silt Dikes.

Installation
 Rock should be placed individually by hand or by mechanical methods (no dumping of rock) to achieve complete ditch or swale coverage.
 Tightly abut bags and stack according to detail shown in the figure at the end of this section (pyramid approach). Gravel bags and sandbags should not be stacked any higher than 3 ft.  Upper rows or gravel and sand bags shall overlap joints in lower rows.  Fiber rolls should be trenched in, backfilled, and firmly staked in place.  Install along a level contour.
 HDPE check dams, temporary silt dikes, and other manufactured products should be used and installed per manufacturer specifications.

Costs
Cost consists of labor costs if materials are readily available (such as gravel on-site). If material must be imported, costs will increase. For other material and installation costs, see SE-5, SE-6, SE-8, SE-12, and SE-14.

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 If the check dam is used as a sediment capture device, sediment that accumulates behind the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches one-third of the barrier height.  If the check dam is used as a grade control structure, sediment removal is not required as long as the system continues to control the grade.
 Inspect areas behind check dams for pools of standing water, especially if subjected to daily non-stormwater discharges.
 Remove accumulated sediment prior to permanent seeding or soil stabilization.  Remove check dam and accumulated sediment when check dams are no longer needed.

References
Draft – Sedimentation and Erosion Control, and Inventory of Current Practices, USEPA, April 1990.

Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

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Description and Purpose
A fiber roll (also known as wattles or logs) consists of straw, coir, curled wood fiber, or other biodegradable materials bound into a tight tubular roll wrapped by plastic netting, which can be photodegradable, or natural fiber, such as jute, cotton, or sisal. Additionally, gravel core fiber rolls are available, which contain an imbedded ballast material such as gravel or sand for additional weight when staking the rolls are not feasible (such as use as inlet protection). When fiber rolls are placed at the toe and on the face of slopes along the contours, they intercept runoff, reduce its flow velocity, release the runoff as sheet flow, and provide removal of sediment from the runoff (through sedimentation). By interrupting the length of a slope, fiber rolls can also reduce sheet and rill erosion until vegetation is established.

Suitable Applications
Fiber rolls may be suitable:
 Along the toe, top, face, and at grade breaks of exposed and erodible slopes to shorten slope length and spread runoff as sheet flow.
 At the end of a downward slope where it transitions to a steeper slope.
 Along the perimeter of a project.
 As check dams in unlined ditches with minimal grade.
 Down-slope of exposed soil areas.

Bacteria
Oil and Grease
Organics

Potential Alternatives
SE-1 Silt Fence
SE-6 Gravel Bag Berm
SE-8 Sandbag Barrier
SE-12 Manufactured Linear Sediment Controls
SE-14 Biofilter Bags
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 At operational storm drains as a form of inlet protection.  Around temporary stockpiles.

Limitations
 Fiber rolls should be used in conjunction with erosion control, such as hydroseed, RECPs, etc.
 Only biodegradable fiber rolls containing no plastic can remain on a site applying for a Notice of Termination due to plastic pollution and wildlife concerns (State Water Board, 2016). Fiber rolls containing plastic that are used on a site must be disposed of for final stabilization.
 Fiber rolls are not effective unless trenched in and staked. If not properly staked and trenched in, fiber rolls will not work as intended and could be transported by high flows.  Not intended for use in high flow situations (i.e., for concentrated flows).  Difficult to move once saturated.
 Fiber rolls have a limited sediment capture zone.
 Fiber rolls should not be used on slopes subject to creep, slumping, or landslide.  Rolls typically function for 12-24 months, depending upon local conditions and roll material.

Implementation
Fiber Roll Materials
 Fiber rolls should be prefabricated.
 Fiber rolls may come manufactured containing polyacrylamide (PAM), a flocculating agent within the roll. Fiber rolls impregnated with PAM provide additional sediment removal capabilities and should be used in areas with fine, clayey or silty soils to provide additional sediment removal capabilities. Monitoring may be required for these installations.  Fiber rolls are made from weed-free rice straw, flax, curled wood fiber, or coir bound into a tight tubular roll by netting or natural fiber (see Limitations above regarding plastic netting).
 Typical fiber rolls vary in diameter from 6 in. to 20 in. Larger diameter rolls are available as well. The larger the roll, the higher the sediment retention capacity.  Typical fiber rolls lengths are 4, 10, 20 and 25 ft., although other lengths are likely available.

Installation
 Locate fiber rolls on level contours spaced as follows:
Slope inclination of 4:1 (H:V) or flatter: Fiber rolls should be placed at a maximum interval of 20 ft.

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Slope inclination between 4:1 and 2:1 (H:V): Fiber Rolls should be placed at a maximum interval of 15 ft. (a closer spacing is more effective). Slope inclination 2:1 (H:V) or greater: Fiber Rolls should be placed at a maximum interval of 10 ft. (a closer spacing is more effective).  Prepare the slope before beginning installation.
 Dig small trenches across the slope on the contour. The trench depth should be ¼ to 1/3 of the thickness of the roll, and the width should equal the roll diameter, in order to provide area to backfill the trench.
 It is critical that rolls are installed perpendicular to water movement, and parallel to the slope contour.
 Start building trenches and installing rolls from the bottom of the slope and work up.  It is recommended that pilot holes be driven through the fiber roll. Use a straight bar to drive holes through the roll and into the soil for the wooden stakes.  Turn the ends of the fiber roll up slope to prevent runoff from going around the roll.  Stake fiber rolls into the trench.
Drive stakes at the end of each fiber roll and spaced 4 ft maximum on center. Use wood stakes with a nominal classification of 0.75 by 0.75 in. and minimum length of 24 in.
 If more than one fiber roll is placed in a row, the rolls should be overlapped, not abutted.  See typical fiber roll installation details at the end of this fact sheet.

Removal
 Fiber rolls can be left in place or removed depending on the type of fiber roll and application (temporary vs. permanent installation). Fiber rolls encased with plastic netting or containing any plastic material will need to be removed from the site for final stabilization.

Fiber rolls used in a permanent application are to be encased with a non-plastic material and are left in place. Removal of a fiber roll used in a permanent application can result in greater disturbance; therefore, during the BMP planning phase, the areas where fiber rolls will be used on final slopes, only fiber rolls wrapped in non-plastic material should be selected.  Temporary installations should only be removed when up gradient areas are stabilized per General Permit requirements, and/or pollutant sources no longer present a hazard. But they should also be removed before vegetation becomes too mature so that the removal process does not disturb more soil and vegetation than is necessary.

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Costs
Material costs for straw fiber rolls range from $26 - $38 per 25-ft. roll1 and curled wood fiber rolls range from $30 - $40 per roll2.

Material costs for PAM impregnated fiber rolls range between $9.00-$12.00 per linear foot, based upon vendor research1 .

Inspection and Maintenance
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Repair or replace split, torn, unraveling, or slumping fiber rolls.  If the fiber roll is used as a sediment capture device, or as an erosion control device to maintain sheet flows, sediment that accumulates in the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when sediment accumulation reaches one-third the designated sediment storage depth.  If fiber rolls are used for erosion control, such as in a check dam, sediment removal should not be required as long as the system continues to control the grade. Sediment control BMPs will likely be required in conjunction with this type of application.  Repair any rills or gullies promptly.

References
General Construction – Frequently Asked Questions, Storm Water Program website, State Water Resources Control Board, 2009 updated in 2016. Available online at:
http://www.waterboards.ca.gov/water_issues/programs/stormwater/gen_const_faq.shtml .

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

1 Adjusted for inflation (2016 dollars) by Tetra Tech, Inc. 2 Costs estimated based on vendor query by Tetra Tech, Inc. 2016.

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Description and Purpose
A gravel bag berm is a series of gravel-filled bags placed on a level contour to intercept sheet flows. Gravel bags pond sheet flow runoff, allowing sediment to settle out, and release runoff slowly as sheet flow, preventing erosion.

Suitable Applications
Gravel bag berms may be suitable:
 As a linear sediment control measure:
Below the toe of slopes and erodible slopes
As sediment traps at culvert/pipe outlets
Below other small cleared areas
Along the perimeter of a site
Down slope of exposed soil areas
Around temporary stockpiles and spoil areas
Parallel to a roadway to keep sediment off paved areas Along streams and channels
 As a linear erosion control measure:
- Along the face and at grade breaks of exposed and
erodible slopes to shorten slope length and spread
runoff as sheet flow.

Potential Alternatives
SE-1 Silt Fence
SE-5 Fiber Roll
SE-8 Sandbag Barrier
SE-12 Temporary Silt Dike
SE-14 Biofilter Bags
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At the top of slopes to divert runoff away from disturbed slopes. As chevrons (small check dams) across mildly sloped construction roads. For use check dam use in channels, see SE-4, Check Dams.

Limitations
 Gravel berms may be difficult to remove.
 Removal problems limit their usefulness in landscaped areas.  Gravel bag berm may not be appropriate for drainage areas greater than 5 acres.  Runoff will pond upstream of the berm, possibly causing flooding if sufficient space does not exist.
 Degraded gravel bags may rupture when removed, spilling contents.  Installation can be labor intensive.
 Durability of gravel bags is somewhat limited, and bags may need to be replaced when installation is required for longer than 6 months.
 Easily damaged by construction equipment.
 When used to detain concentrated flows, maintenance requirements increase.

Implementation
General
A gravel bag berm consists of a row of open graded gravel-filled bags placed on a level contour.

When appropriately placed, a gravel bag berm intercepts and slows sheet flow runoff, causing temporary ponding. The temporary ponding allows sediment to settle. The open graded gravel in the bags is porous, which allows the ponded runoff to flow slowly through the bags, releasing the runoff as sheet flows. Gravel bag berms also interrupt the slope length and thereby reduce erosion by reducing the tendency of sheet flows to concentrate into rivulets, which erode rills, and ultimately gullies, into disturbed, sloped soils. Gravel bag berms are similar to sand bag barriers but are more porous. Generally, gravel bag berms should be used in conjunction with temporary soil stabilization controls up slope to provide effective erosion and sediment control.

Design and Layout
 Locate gravel bag berms on level contours.
 When used for slope interruption, the following slope/sheet flow length combinations apply:
Slope inclination of 4:1 (H:V) or flatter: Gravel bags should be placed at a maximum interval of 20 ft, with the first row near the slope toe. Slope inclination between 4:1 and 2:1 (H:V): Gravel bags should be placed at a maximum interval of 15 ft. (a closer spacing is more effective), with the first row near the slope toe.

Gravel Bag Berm SE-6
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Slope inclination 2:1 (H:V) or greater: Gravel bags should be placed at a maximum interval of 10 ft. (a closer spacing is more effective), with the first row near the slope toe.  Turn the ends of the gravel bag barriers up slope to prevent runoff from going around the berm.
 Allow sufficient space up slope from the gravel bag berm to allow ponding, and to provide room for sediment storage.
 For installation near the toe of the slope, gravel bag barriers should be set back from the slope toe to facilitate cleaning. Where specific site conditions do not allow for a set-back, the gravel bag barrier may be constructed on the toe of the slope. To prevent flows behind the barrier, bags can be placed perpendicular to a berm to serve as cross barriers.  Drainage area should not exceed 5 acres.
 In Non-Traffic Areas:
Height = 18 in. maximum
Top width = 24 in. minimum for three or more-layer construction Top width = 12 in. minimum for one- or two-layer construction Side slopes = 2:1 (H:V) or flatter
 In Construction Traffic Areas:
Height = 12 in. maximum
Top width = 24 in. minimum for three or more-layer construction. Top width = 12 in. minimum for one- or two-layer construction. Side slopes = 2:1 (H:V) or flatter.
 Butt ends of bags tightly.
 On multiple row, or multiple layer construction, overlap butt joints of adjacent row and row beneath.
 Use a pyramid approach when stacking bags.

Materials
 Bag Material: Bags should be woven polypropylene, polyethylene or polyamide fabric or burlap, minimum unit weight of 4 ounces/yd2, Mullen burst strength exceeding 300 lb/in2 in conformance with the requirements in ASTM designation D3786, and ultraviolet stability exceeding 70% in conformance with the requirements in ASTM designation D4355.

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 Bag Size: Each gravel-filled bag should have a length of 18 in., width of 12 in., thickness of 3 in., and mass of approximately 33 lbs. Bag dimensions are nominal and may vary based on locally available materials.
 Fill Material: Fill material should be 0.5 to 1 in. Crushed rock, clean and free from clay, organic matter, and other deleterious material, or other suitable open graded, non-cohesive, porous gravel.

Costs
Material costs for gravel bags are average and are dependent upon material availability. $3.20- $3.80 per filled gravel bag is standard based upon vendor research (Adjusted for inflation, 2016 dollars, by Tetra Tech, Inc.).

Inspection and Maintenance
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Gravel bags exposed to sunlight will need to be replaced every two to three months due to degrading of the bags.
 Reshape or replace gravel bags as needed.
 Repair washouts or other damage as needed.
 Sediment that accumulates in the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches one-third of the barrier height.
 Remove gravel bag berms when no longer needed and recycle gravel fill whenever possible and properly dispose of bag material. Remove sediment accumulation and clean, re-grade, and stabilize the area.

References
Handbook of Steel Drainage and Highway Construction, American Iron and Steel Institute, 1983.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Pollution Plan Handbook, First Edition, State of California, Department of Transportation Division of New Technology, Materials and Research, October 1992.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

Street Sweeping and Vacuuming SE-7
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Description and Purpose
Street sweeping and vacuuming includes use of self-propelled and walk-behind equipment to remove sediment from streets and roadways and to clean paved surfaces in preparation for final paving. Sweeping and vacuuming prevents sediment from the project site from entering storm drains or receiving waters.

Suitable Applications
Sweeping and vacuuming are suitable anywhere sediment is tracked from the project site onto public or private paved streets and roads, typically at points of egress. Sweeping and vacuuming are also applicable during preparation of paved surfaces for final paving.

Limitations
 Sweeping and vacuuming may not be effective when
sediment is wet or when tracked soil is caked (caked soil may need to be scraped loose).
 Sweeping may be less effective for fine particle soils (i.e., clay).

Implementation
 Controlling the number of points where vehicles can leave the site will allow sweeping and vacuuming efforts to be focused and perhaps save money.
 Inspect potential sediment tracking locations daily.

Categories
EC Erosion Control
SE Sediment Control 
TC Tracking Control 
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients
Trash 
Metals
Bacteria
Oil and Grease 
Organics

Potential Alternatives
None
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Street Sweeping and Vacuuming SE-7
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 Visible sediment tracking should be swept or vacuumed on a daily basis.  Do not use kick brooms or sweeper attachments. These tend to spread the dirt rather than remove it.
 If not mixed with debris or trash, consider incorporating the removed sediment back into the project
Costs
Rental rates for self-propelled sweepers vary depending on hopper size and duration of rental.

Expect rental rates from $ 650/day to $2,500/day1, plus operator costs. Hourly production rates vary with the amount of area to be swept and amount of sediment. Match the hopper size to the area and expect sediment load to minimize time spent dumping.

Inspection and Maintenance
 Inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 When actively in use, points of ingress and egress must be inspected daily.  When tracked or spilled sediment is observed outside the construction limits, it must be removed at least daily. More frequent removal, even continuous removal, may be required in some jurisdictions.
 Be careful not to sweep up any unknown substance or any object that may be potentially hazardous.
 Adjust brooms frequently; maximize efficiency of sweeping operations.  After sweeping is finished, properly dispose of sweeper wastes at an approved dumpsite.

References
Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

1 Based on contractor query conducted by Tetra Tech, Inc. November 2016.

Storm Drain Inlet Protection SE-10
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Description and Purpose
Storm drain inlet protection consists of a sediment filter or an impounding area in, around or upstream of a storm drain, drop inlet, or curb inlet. Storm drain inlet protection measures temporarily pond runoff before it enters the storm drain, allowing sediment to settle. Some filter configurations also remove sediment by filtering, but usually the ponding action results in the greatest sediment reduction. Temporary
geotextile storm drain inserts attach underneath storm drain grates to capture and filter storm water.

Suitable Applications
 Every storm drain inlet receiving runoff from unstabilized or otherwise active work areas should be protected. Inlet protection should be used in conjunction with other erosion and sediment controls to prevent sediment-laden
stormwater and non-stormwater discharges from entering
the storm drain system.

Limitations
 Drainage area should not exceed 1 acre.
 In general straw bales should not be used as inlet
protection.
 Requires an adequate area for water to pond without
encroaching into portions of the roadway subject to traffic.  Sediment removal may be inadequate to prevent sediment discharges in high flow conditions or if runoff is heavily sediment laden. If high flow conditions are expected, use Categories
EC Erosion Control
SE Sediment Control 
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash 
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
SE-1 Silt Fence
SE-5 Fiber Rolls
SE-6 Gravel Bag Berm
SE-8 Sandbag Barrier
SE-14 Biofilter Bags
SE-13 Compost Socks and Berms
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Storm Drain Inlet Protection SE-10
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other onsite sediment trapping techniques in conjunction with inlet protection.  Frequent maintenance is required.
 Limit drainage area to 1 acre maximum. For drainage areas larger than 1 acre, runoff should be routed to a sediment-trapping device designed for larger flows. See BMPs SE-2, Sediment Basin, and SE-3, Sediment Traps.
 Excavated drop inlet sediment traps are appropriate where relatively heavy flows are expected, and overflow capability is needed.

Implementation
General
Inlet control measures presented in this handbook should not be used for inlets draining more than one acre. Runoff from larger disturbed areas should be first routed through SE-2, Sediment Basin or SE-3, Sediment Trap and/or used in conjunction with other drainage control, erosion control, and sediment control BMPs to protect the site. Different types of inlet protection are appropriate for different applications depending on site conditions and the type of inlet. Alternative methods are available in addition to the methods described/shown herein such as prefabricated inlet insert devices, or gutter protection devices.

Design and Layout
Identify existing and planned storm drain inlets that have the potential to receive sediment- laden surface runoff. Determine if storm drain inlet protection is needed and which method to use.
 The key to successful and safe use of storm drain inlet protection devices is to know where runoff that is directed toward the inlet to be protected will pond or be diverted as a result of installing the protection device.
Determine the acceptable location and extent of ponding in the vicinity of the drain inlet.

The acceptable location and extent of ponding will influence the type and design of the storm drain inlet protection device.
Determine the extent of potential runoff diversion caused by the storm drain inlet protection device. Runoff ponded by inlet protection devices may flow around the device and towards the next downstream inlet. In some cases, this is acceptable; in other cases, serious erosion or downstream property damage can be caused by these diversions. The possibility of runoff diversions will influence whether or not storm drain inlet protection is suitable; and, if suitable, the type and design of the device.  The location and extent of ponding, and the extent of diversion, can usually be controlled through appropriate placement of the inlet protection device. In some cases, moving the inlet protection device a short distance upstream of the actual inlet can provide more efficient sediment control, limit ponding to desired areas, and prevent or control diversions.  Seven types of inlet protection are presented below. However, it is recognized that other effective methods and proprietary devices exist and may be selected.

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Silt Fence: Appropriate for drainage basins with less than a 5% slope, sheet flows, and flows under 0.5 cfs.
Excavated Drop Inlet Sediment Trap: An excavated area around the inlet to trap sediment (SE-3).
Gravel bag barrier: Used to create a small sediment trap upstream of inlets on sloped, paved streets. Appropriate for sheet flow or when concentrated flow may exceed 0.5 cfs, and where overtopping is required to prevent flooding.
Block and Gravel Filter: Appropriate for flows greater than 0.5 cfs. Temporary Geotextile Storm drain Inserts: Different products provide different features.

Refer to manufacturer details for targeted pollutants and additional features. Biofilter Bag Barrier: Used to create a small retention area upstream of inlets and can be located on pavement or soil. Biofilter bags slowly filter runoff allowing sediment to settle out. Appropriate for flows under 0.5 cfs.
Compost Socks: Allow filtered run-off to pass through the compost while retaining sediment and potentially other pollutants (SE-13). Appropriate for flows under 1.0 cfs.  Select the appropriate type of inlet protection and design as referred to or as described in this fact sheet.
 Provide area around the inlet for water to pond without flooding structures and property.  Grates and spaces around all inlets should be sealed to prevent seepage of sediment-laden water.
 Excavate sediment sumps (where needed) 1 to 2 ft with 2:1 side slopes around the inlet.

Installation
 DI Protection Type 1 - Silt Fence - Similar to constructing a silt fence; see BMP SE-1, Silt Fence. Do not place fabric underneath the inlet grate since the collected sediment may fall into the drain inlet when the fabric is removed or replaced and water flow through the grate will be blocked resulting in flooding. See typical Type 1 installation details at the end of this fact sheet.

1. Excavate a trench approximately 6 in. wide and 6 in. deep along the line of the silt fence inlet protection device.

2. Place 2 in. by 2 in. wooden stakes around the perimeter of the inlet a maximum of 3 ft apart and drive them at least 18 in. into the ground or 12 in. below the bottom of the trench. The stakes should be at least 48 in.

3. Lay fabric along bottom of trench, up side of trench, and then up stakes. See SE-1, Silt Fence, for details. The maximum silt fence height around the inlet is 24 in.

4. Staple the filter fabric (for materials and specifications, see SE-1, Silt Fence) to wooden stakes. Use heavy-duty wire staples at least 1 in. in length.

Storm Drain Inlet Protection SE-10
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5. Backfill the trench with gravel or compacted earth all the way around.  DI Protection Type 2 - Excavated Drop Inlet Sediment Trap - Install filter fabric fence in accordance with DI Protection Type 1. Size excavated trap to provide a minimum storage capacity calculated at the rate 67 yd3/acre of drainage area. See typical Type 2 installation details at the end of this fact sheet.
 DI Protection Type 3 - Gravel bag - Flow from a severe storm should not overtop the curb. In areas of high clay and silts, use filter fabric and gravel as additional filter media.

Construct gravel bags in accordance with SE-6, Gravel Bag Berm. Gravel bags should be used due to their high permeability. See typical Type 3 installation details at the end of this fact sheet.

1. Construct on gently sloping street.

2. Leave room upstream of barrier for water to pond and sediment to settle.

3. Place several layers of gravel bags – overlapping the bags and packing them tightly together.

4. Leave gap of one bag on the top row to serve as a spillway. Flow from a severe storm (e.g., 10-year storm) should not overtop the curb.
 DI Protection Type 4 – Block and Gravel Filter - Block and gravel filters are suitable for curb inlets commonly used in residential, commercial, and industrial construction. See typical Type 4 installation details at the end of this fact sheet.

1. Place hardware cloth or comparable wire mesh with 0.5 in. openings over the drop inlet so that the wire extends a minimum of 1 ft beyond each side of the inlet structure. If more than one strip is necessary, overlap the strips. Place woven geotextile over the wire mesh.

2. Place concrete blocks lengthwise on their sides in a single row around the perimeter of the inlet, so that the open ends face outward, not upward. The ends of adjacent blocks should abut. The height of the barrier can be varied, depending on design needs, by stacking combinations of blocks that are 4 in., 8 in., and 12 in. wide. The row of blocks should be at least 12 in. but no greater than 24 in. high.

3. Place wire mesh over the outside vertical face (open end) of the concrete blocks to prevent stone from being washed through the blocks. Use hardware cloth or comparable wire mesh with 0.5 in. opening.

4. Pile washed stone against the wire mesh to the top of the blocks. Use 0.75 to 3 in.  DI Protection Type 5 – Temporary Geotextile Insert (proprietary) – Many types of temporary inserts are available. Most inserts fit underneath the grate of a drop inlet or inside of a curb inlet and are fastened to the outside of the grate or curb. These inserts are removable, and many can be cleaned and reused. Installation of these inserts differs between manufacturers. Please refer to manufacturer instruction for installation of proprietary devices.

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 DI Protection Type 6 - Biofilter bags – Biofilter bags may be used as a substitute for gravel bags in low-flow situations. Biofilter bags should conform to specifications detailed in SE-14, Biofilter bags.

1. Construct in a gently sloping area.

2. Biofilter bags should be placed around inlets to intercept runoff flows.

3. All bag joints should overlap by 6 in.

4. Leave room upstream for water to pond and for sediment to settle out.

5. Stake bags to the ground as described in the following detail. Stakes may be omitted if bags are placed on a paved surface.
 DI Protection Type 7 – Compost Socks – A compost sock can be assembled on site by filling a mesh sock (e.g., with a pneumatic blower). Compost socks do not require special trenching compared to other sediment control methods (e.g., silt fence). Compost socks should conform to specification detailed in SE-13, Compost Socks and Berms.

Costs
 Average annual cost for installation and maintenance of DI Type 1-4 and 6 (one-year useful life) is $200 per inlet.
 Temporary geotextile inserts are proprietary, and cost varies by region. These inserts can often be reused and may have greater than 1 year of use if maintained and kept undamaged.

Average cost per insert ranges from $50-75 plus installation, but costs can exceed $100.

This cost does not include maintenance.
 See SE-13 for Compost Sock cost information.

Inspection and Maintenance
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Silt Fences. If the fabric becomes clogged, torn, or degrades, it should be replaced. Make sure the stakes are securely driven in the ground and are in good shape (i.e., not bent, cracked, or splintered, and are reasonably perpendicular to the ground). Replace damaged stakes. At a minimum, remove the sediment behind the fabric fence when accumulation reaches one-third the height of the fence or barrier height.  Gravel Filters. If the gravel becomes clogged with sediment, it should be carefully removed from the inlet and either cleaned or replaced. Since cleaning gravel at a construction site may be difficult, consider using the sediment-laden stone as fill material and put fresh stone around the inlet. Inspect bags for holes, gashes, and snags, and replace bags as needed.

Check gravel bags for proper arrangement and displacement.

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 Sediment that accumulates in the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches one-third of the barrier height.
 Inspect and maintain temporary geotextile insert devices according to manufacturer’s specifications.
 Remove storm drain inlet protection once the drainage area is stabilized. Clean and regrade area around the inlet and clean the inside of the storm drain inlet, as it should be free of sediment and debris at the time of final inspection.

References
Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Management Manual for The Puget Sound Basin, Washington State Department of Ecology, Public Review Draft, 1991.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

Storm Drain Inlet Protection SE-10
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Storm Drain Inlet Protection SE-10
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Storm Drain Inlet Protection SE-10
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Gravel bags
Gravel bags

6. Protection can be effective even if it is not immediately adjacent to the inlet provided that the inlet is protected from potential sources of pollution.

Storm Drain Inlet Protection SE-10
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Manufactured Linear Sediment Controls
(MLSC) SE-12
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Description and Purpose
Manufactured linear sediment controls (MLSC) are pre-
manufactured devices that are typically specified and installed for drainage and sediment control on the perimeter of
disturbed sites or stockpiles and as check dams within
channels. Typically, MLSCs can be reused.

This fact sheet is intended to provide guidance on BMP
selection and implementation of proprietary or vendor-
supplied products, for sediment control. Products should be evaluated for project-specific implementation and used if determined to be appropriate by the SWPPP Preparer.

Suitable Applications
MLSCs are generally used in areas as a substitute for fiber rolls and silt fences in sediment control applications to slow down runoff water, divert drainage or contain fines and sediment.

MLSCs are a linear control and application suitability varies based on the specific product type. They may be suitable:
 On paved surfaces for perimeter protection.
 As check structures in channels.
 Along the perimeter of disturbed sites in lieu of silt fence.

Categories
EC Erosion Control 
SE Sediment Control 
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash 
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
SE-1 Silt Fence
SE-5 Fiber Roll
SE-6 Gravel Bag Berm
SE-8 Sandbag Barrier
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Manufactured Linear Sediment Controls
(MLSC) SE-12
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 At operational storm drains as a form of inlet protection.  Around temporary stockpiles or material/equipment storage areas.  At the interface between graveled driveways and pavement.  Along the toe of exposed and erodible slopes.

Limitations
 Limitations vary by product. Product manufacturer’s printed product use instructions should be reviewed by the SWPPP Preparer to determine the project-specific applicability of MLSCs.

Implementation
General
When appropriately placed, MLSCs intercept and slow sheet flow runoff, causing temporary ponding. The temporary ponding provides quiescent conditions allowing sediment to settle. The device is porous, which allows the ponded runoff to flow slowly through the device, releasing the runoff as sheet flows. Generally, MLSCs should be used in conjunction with temporary soil stabilization controls up-slope to provide an effective combination of erosion and sediment control.

Design and Layout
 MLSCs used on soil should be trenched or attached to the ground per manufacturer specifications in a manner that precludes runoff or ponded water from flowing around or under the device.
 MLSCs designed for use on asphalt or concrete may be attached using a variety of methods, including nailing the device to the pavement, or using a high strength adhesive.  Follow manufacturer written specifications when installing MLSCs.  Allow sufficient space up-slope from the silt dike to allow ponding, and to provide room for sediment storage.
 For installation near the toe of the slope, MLSCs should be set back 3 feet from the slope toe to facilitate cleaning. Where site conditions do not allow set back, the sediment control may be constructed on the toe of the slope. To prevent flows behind the barrier, sand or gravel bags can be placed perpendicular and between the sediment control and slope to serve as a barrier to parallel flow.
 Drainage area should not exceed 5 acres.

Materials
 Several manufactured products are available. The following search terms or combination of terms can be used with an internet search engine to find manufactured linear sediment controls:

Manufactured Linear Sediment Controls
(MLSC) SE-12
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- “silt barrier”
- “reusable silt fence”
- “silt fence alternative” or
- “perimeter sediment control”
Costs
Manufacturers should be contacted directly for current pricing.

Inspection and Maintenance
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Reshape or replace sections of damaged MLSCs as needed.  Repair washouts or other damage as needed.
 Sediment that accumulates behind the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches one-third of the barrier height.
 Remove MLSCs when no longer needed. Remove sediment accumulation and clean, re- grade, and stabilize the area. Removed sediment should be incorporated in the project or disposed of properly.

References
City of Elko Construction Site Best Management Practices Handbook, December 2005.

Construction Site Best Management Practices Handbook, June 2008 Update, Truckee Meadows Regional Stormwater Quality Management Program, June 2008.

Complying with the Edwards Aquifer Rules Technical Guidance on Best Management Practices, Texas Commission on Environmental Quality, Revised July 2005, Addendum Sheet, January26, 2011.

Stormwater Management Manual for Western Washington Volume II, Construction Stormwater Pollution Prevention, Washington State Department of Ecology, February 2005.

Biofilter Bags SE-14
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Description and Purpose
Biofilter bags, or bio-bags, are a multi-purpose sediment control BMP consisting of a plastic mesh bag filled with 100% recycled wood product waste. Biofilter bags come in a variety of sizes (30” x 18” and 30” x 9” being common) and generally have between 1-2 cubic yards of recycled wood waste (or wood chips). Biofilter bags work by detaining flow and allowing a slow rate of discharge through the wood media. This action removes suspended sediment through gravity settling of the detained water and filtration within the bag.

Suitable Applications
Biofilter bags are a short-term BMP that can be rapidly deployed, maintained, and replaced. Biofilter bags can be an effective short-term solution to place in developed rills to prevent further erosion until permanent measures can be established. Suitable short-term applications include:
 As a linear sediment control measure:
- Below the toe of slopes and erodible slopes
- Below other small cleared areas
- Along the perimeter of a site (with low-expected flow) - Down slope of exposed soil areas
- Around temporary stockpiles and spoil areas
- Parallel to a roadway to keep sediment off paved areas Categories
EC Erosion Control
SE Sediment Control 
TR Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
SE-1 Silt Fence
SE-4 Check Dams
SE-5 Fiber Roll
SE-6 Gravel Bag Berm
SE-8 Sandbag Barrier
SE-10 Storm Drain Inlet Protection
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Biofilter Bags SE-14
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- Along streams and channels
 As linear erosion control measure:
- Along the face and at grade breaks of exposed and erodible slopes to shorten slope length and spread runoff as sheet flow
- At the top of slopes to divert runoff away from disturbed slopes - As check dams across mildly sloped construction roads  Inlet Protection (See SE-10)
 Supplement to silt fences or other sediment control devices Limitations
 Short life-span (maximum usefulness of 2-3 months and should be replaced more frequently if needed); regular maintenance and replacement required to ensure effectiveness. Bags will rapidly fill with sediment and reduce permeability.
 Easily damaged by construction vehicles.
 If not properly staked, will fail on slope applications.  If improperly installed can allow undercutting or side-cutting flow.  Not effective where water velocities or volumes are high.  Potentially buoyant and easily displaced if not properly installed.

Implementation
General
Biofilter bags are a relatively low cost temporary BMP that are easily deployed and have a simple installation that can be performed by hand. Without proper installation, however, biofilter bags can fail due to their light weight, potential displacement, and multiple joint locations. One of the benefits of utilizing biofilter bags is that the media (wood-product) can be recycled or used onsite when no longer needed (where acceptable).

Design and Layout – Linear control
 Locate biofilter bags on level contours.
- Slopes between 20:1 and 4:1 (H:V): Biofilter bags should be placed at a maximum interval of 20 ft, with the first row near the slope toe. - Slopes between 4:1 and 2:1 (H:V): Biofilter bags should be placed at a maximum interval of 15 ft, with the first row near the slope toe.
- Slopes 2:1 (H:V) or steeper: Biofilter bags should be placed at a maximum interval of 10 ft., with the first row placed the slope toe.

Biofilter Bags SE-14
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 Turn the ends of the biofilter bag barriers up slope to prevent runoff from going around the berm.
 Allow sufficient space up slope from the biofilter bag berm to allow ponding, and to provide room for sediment storage.
 Stake biofilter bags into a 1 to 2 in. deep trench with a width equal to the bag. - Drive one stake at each end of the bag.
- Use wood stakes with a nominal classification of 0.75 by 0.75 in. and minimum length of 24 in.
 Biofilter bags should be overlapped (6 in.), not abutted.

Costs
Pre-filled biofilter bags cost approximately $3.20-$4.50 per bag, dependent upon size (Adjusted for inflation, 2016 dollars, by Tetra Tech, Inc.).

Inspection and Maintenance
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Biofilter bags exposed to sunlight will need to be replaced every two to three months due to degrading of the bags.
 Reshape or replace biofilter bags as needed.
 Repair washouts or other damage as needed.
 Sediment that is retained by the BMP should be periodically removed in order to maintain BMP effectiveness. Sediment should be removed when the sediment accumulation reaches one-third of the barrier height.
 Remove biofilter bag berms when no longer needed. Remove sediment accumulation and clean, re-grade, and stabilize the area. Biofilter media may be used on-site, if allowed.

References
Catalog of Stormwater Best Management Practices for Idaho Cities and Counties. Volume 2, Section 7, BMP 34 – Biofilter Bags, Idaho Department of Environmental Quality, 2005.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Wind Erosion Control WE-1
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Description and Purpose
Wind erosion or dust control consists of applying water or other chemical dust suppressants as necessary to prevent or alleviate dust nuisance generated by construction activities. Covering small stockpiles or areas is an alternative to applying water or other dust palliatives.

California’s Mediterranean climate, with a short “wet” season and a typically long, hot “dry” season, allows the soils to thoroughly dry out. During the dry season, construction activities are at their peak, and disturbed and exposed areas are increasingly subject to wind erosion, sediment tracking, and dust generated by construction equipment. Site conditions and climate can make dust control more of an erosion problem than water-based erosion. Additionally, many local agencies, including Air Quality Management Districts, require dust control and/or dust control permits in order to comply with local nuisance laws, opacity laws (visibility impairment) and the requirements of the Clean Air Act. Wind erosion control is required to be implemented at all construction sites greater than 1 acre by the General Permit.

Suitable Applications
Most BMPs that provide protection against water-based erosion will also protect against wind-based erosion and dust control requirements required by other agencies will generally meet wind erosion control requirements for water quality protection.

Wind erosion control BMPs are suitable during the following construction activities:

Categories
EC Erosion Control
SE Sediment Control 
TC Tracking Control
WE Wind Erosion Control 
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
EC-5 Soil Binders
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Wind Erosion Control WE-1
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 Construction vehicle traffic on unpaved roads
 Drilling and blasting activities
 Soils and debris storage piles
 Batch drop from front-end loaders
 Areas with unstabilized soil
 Final grading/site stabilization
Limitations
 Watering prevents dust only for a short period (generally less than a few hours) and should be applied daily (or more often) to be effective.
 Over watering may cause erosion and track-out.
 Oil or oil-treated subgrade should not be used for dust control because the oil may migrate into drainageways and/or seep into the soil.
 Chemical dust suppression agents may have potential environmental impacts. Selected chemical dust control agents should be environmentally benign.  Effectiveness of controls depends on soil, temperature, humidity, wind velocity and traffic.  Chemical dust suppression agents should not be used within 100 feet of wetlands or water bodies.
 Chemically treated subgrades may make the soil water repellant, interfering with long-term infiltration and the vegetation/re-vegetation of the site. Some chemical dust suppressants may be subject to freezing and may contain solvents and should be handled properly.  In compacted areas, watering and other liquid dust control measures may wash sediment or other constituents into the drainage system.
 If the soil surface has minimal natural moisture, the affected area may need to be pre-wetted so that chemical dust control agents can uniformly penetrate the soil surface.

Implementation
Dust Control Practices
Dust control BMPs generally stabilize exposed surfaces and minimize activities that suspend or track dust particles. The following table presents dust control practices that can be applied to varying site conditions that could potentially cause dust. For heavily traveled and disturbed areas, wet suppression (watering), chemical dust suppression, gravel asphalt surfacing, temporary gravel construction entrances, equipment wash-out areas, and haul truck covers can be employed as dust control applications. Permanent or temporary vegetation and mulching can be employed for areas of occasional or no construction traffic. Preventive measures include minimizing surface areas to be disturbed, limiting onsite vehicle traffic to 15 mph or less, and controlling the number and activity of vehicles on a site at any given time.

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Chemical dust suppressants include: mulch and fiber based dust palliatives (e.g. paper mulch with gypsum binder), salts and brines (e.g. calcium chloride, magnesium chloride), non- petroleum based organics (e.g. vegetable oil, lignosulfonate), petroleum based organics (e.g. asphalt emulsion, dust oils, petroleum resins), synthetic polymers (e.g. polyvinyl acetate, vinyl, acrylic), clay additives (e.g. bentonite, montmorillonite) and electrochemical products (e.g. enzymes, ionic products).

Site Condition
Dust Control Practices
Permanent Vegetation Mulching Wet Suppression (Watering) Chemical Dust Suppression
Gravel or Asphalt
Temporary Gravel Construction Entrances/Equipment Wash Down Synthetic Covers
Minimize Extent of Disturbed Area
Disturbed Areas not Subject to Traffic

X X X X X X
Disturbed Areas Subject to Traffic

X X X X X
Material Stockpiles X X X X X
Demolition X X X
Clearing/ Excavation X X X
Truck Traffic on Unpaved Roads

X X X X X
Tracking X X

Additional preventive measures include:
 Schedule construction activities to minimize exposed area (see EC-1, Scheduling).  Quickly treat exposed soils using water, mulching, chemical dust suppressants, or stone/gravel layering.
 Identify and stabilize key access points prior to commencement of construction.  Minimize the impact of dust by anticipating the direction of prevailing winds.  Restrict construction traffic to stabilized roadways within the project site, as practicable.  Water should be applied by means of pressure-type distributors or pipelines equipped with a spray system or hoses and nozzles that will ensure even distribution.  All distribution equipment should be equipped with a positive means of shutoff.  Unless water is applied by means of pipelines, at least one mobile unit should be available at all times to apply water or dust palliative to the project.  If reclaimed waste water is used, the sources and discharge must meet California Department of Health Services water reclamation criteria and the Regional Water Quality

Wind Erosion Control WE-1
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Control Board (RWQCB) requirements. Non-potable water should not be conveyed in tanks or drain pipes that will be used to convey potable water and there should be no connection between potable and non-potable supplies. Non-potable tanks, pipes, and other conveyances should be marked, “NON-POTABLE WATER - DO NOT DRINK.”  Pave or chemically stabilize access points where unpaved traffic surfaces adjoin paved roads.  Provide covers for haul trucks transporting materials that contribute to dust.  Provide for rapid clean up of sediments deposited on paved roads. Furnish stabilized construction road entrances and wheel wash areas.
 Stabilize inactive areas of construction sites using temporary vegetation or chemical stabilization methods.

For chemical stabilization, there are many products available for chemically stabilizing gravel roadways and stockpiles. If chemical stabilization is used, the chemicals should not create any adverse effects on stormwater, plant life, or groundwater and should meet all applicable regulatory requirements.

Costs
Installation costs for water and chemical dust suppression vary based on the method used and the length of effectiveness. Annual costs may be high since some of these measures are effective for only a few hours to a few days.

Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities.
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Check areas protected to ensure coverage.
 Most water-based dust control measures require frequent application, often daily or even multiple times per day. Obtain vendor or independent information on longevity of chemical dust suppressants.

References
Best Management Practices and Erosion Control Manual for Construction Sites, Flood Control District of Maricopa County, Arizona, September 1992.

California Air Pollution Control Laws, California Air Resources Board, updated annually.

Construction Manual, Chapter 4, Section 10, “Dust Control”; Section 17, “Watering”; and Section 18, “Dust Palliative”, California Department of Transportation (Caltrans), July 2001.

Wind Erosion Control WE-1
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Prospects for Attaining the State Ambient Air Quality Standards for Suspended Particulate Matter (PM10), Visibility Reducing Particles, Sulfates, Lead, and Hydrogen Sulfide, California Air Resources Board, April 1991.

Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stabilized Construction Entrance/Exit TC-1
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Description and Purpose
A stabilized construction access is defined by a point of entrance/exit to a construction site that is stabilized to reduce the tracking of mud and dirt onto public roads by construction vehicles.

Suitable Applications
Use at construction sites:
 Where dirt or mud can be tracked onto public roads.
 Adjacent to water bodies.
 Where poor soils are encountered.
 Where dust is a problem during dry weather conditions.

Limitations
 Entrances and exits require periodic top dressing with additional stones.
 This BMP should be used in conjunction with street
sweeping on adjacent public right of way.
 Entrances and exits should be constructed on level ground only.
 Stabilized construction entrances are rather expensive to construct and when a wash rack is included, a sediment trap of some kind must also be provided to collect wash water runoff.

Categories
EC Erosion Control 
SE Sediment Control 
TC Tracking Control 
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
None
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Implementation
General
A stabilized construction entrance is a pad of aggregate underlain with filter cloth located at any point where traffic will be entering or leaving a construction site to or from a public right of way, street, alley, sidewalk, or parking area. The purpose of a stabilized construction entrance is to reduce or eliminate the tracking of sediment onto public rights of way or streets. Reducing tracking of sediments and other pollutants onto paved roads helps prevent deposition of sediments into local storm drains and production of airborne dust.

Where traffic will be entering or leaving the construction site, a stabilized construction entrance should be used. NPDES permits require that appropriate measures be implemented to prevent tracking of sediments onto paved roadways, where a significant source of sediments is derived from mud and dirt carried out from unpaved roads and construction sites.

Stabilized construction entrances are moderately effective in removing sediment from equipment leaving a construction site. The entrance should be built on level ground.

Advantages of the Stabilized Construction Entrance/Exit is that it does remove some sediment from equipment and serves to channel construction traffic in and out of the site at specified locations. Efficiency is greatly increased when a washing rack is included as part of a stabilized construction entrance/exit.

Design and Layout
 Construct on level ground where possible.
 Select 3 to 6 in. diameter stones.
 Use minimum depth of stones of 12 in. or as recommended by soils engineer.  Construct length of 50 ft or maximum site will allow, and 10 ft minimum width or to accommodate traffic.
 Rumble racks constructed of steel panels with ridges and installed in the stabilized entrance/exit will help remove additional sediment and to keep adjacent streets clean.  Provide ample turning radii as part of the entrance.
 Limit the points of entrance/exit to the construction site.  Limit speed of vehicles to control dust.
 Properly grade each construction entrance/exit to prevent runoff from leaving the construction site.
 Route runoff from stabilized entrances/exits through a sediment trapping device before discharge.
 Design stabilized entrance/exit to support heaviest vehicles and equipment that will use it.

Stabilized Construction Entrance/Exit TC-1
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 Select construction access stabilization (aggregate, asphaltic concrete, concrete) based on longevity, required performance, and site conditions. Do not use asphalt concrete (AC) grindings for stabilized construction access/roadway.
 If aggregate is selected, place crushed aggregate over geotextile fabric to at least 12 in. depth, or place aggregate to a depth recommended by a geotechnical engineer. A crushed aggregate greater than 3 in. but smaller than 6 in. should be used.  Designate combination or single purpose entrances and exits to the construction site.  Require that all employees, subcontractors, and suppliers utilize the stabilized construction access.
 Implement SE-7, Street Sweeping and Vacuuming, as needed.  All exit locations intended to be used for more than a two-week period should have stabilized construction entrance/exit BMPs.

Inspection and Maintenance
 Inspect and verify that activity–based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMPs are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.  Inspect local roads adjacent to the site daily. Sweep or vacuum to remove visible accumulated sediment.
 Remove aggregate, separate and dispose of sediment if construction entrance/exit is clogged with sediment.
 Keep all temporary roadway ditches clear.
 Check for damage and repair as needed.
 Replace gravel material when surface voids are visible.  Remove all sediment deposited on paved roadways within 24 hours.  Remove gravel and filter fabric at completion of construction Costs
Average annual cost for installation and maintenance may vary from $1,500 to $6,100 each, averaging $3,100 per entrance. Costs will increase with addition of washing rack and sediment trap. With wash rack, costs range from $1,500 - $7,700 each, averaging $4,600 per entrance (All costs adjusted for inflation, 2016 dollars, by Tetra Tech Inc.

References
Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

Stabilized Construction Entrance/Exit TC-1
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National Management Measures to Control Nonpoint Source Pollution from Urban Areas, USEPA Agency, 2002.

Proposed Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters, Work Group Working Paper, USEPA, April 1992.

Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992.

Virginia Erosion and Sedimentation Control Handbook, Virginia Department of Conservation and Recreation, Division of Soil and Water Conservation, 1991.

Guidance Specifying Management Measures for Nonpoint Pollution in Coastal Waters, EPA 840-B-9-002, USEPA, Office of Water, Washington, DC, 1993.

Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988.

Stabilized Construction Entrance/Exit TC-1
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50’ Typical (1) Length should be extended to 12 times the diameter of the largest construction vehicle tire.
(2) On small sites length should be the maximum allowed by site.

Stabilized Construction Entrance/Exit TC-1
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50’ Typical
(1) Length should be extended to 12 times the diameter of the largest construction vehicle tire.
(2) On small sites length should be the maximum allowed by site.

Stabilized Construction Roadway TC-2
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Description and Purpose
Access roads, subdivision roads, parking areas, and other onsite vehicle transportation routes should be stabilized immediately after grading, and frequently maintained to prevent erosion and control dust.

Suitable Applications
This BMP should be applied for the following conditions:
 Temporary Construction Traffic:
Phased construction projects and offsite road access
Construction during wet weather
 Construction roadways and detour roads:
Where mud tracking is a problem during wet weather
Where dust is a problem during dry weather
Adjacent to water bodies
Where poor soils are encountered
Limitations
 The roadway must be removed or paved when construction is complete.

Potential Alternatives
None
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 Certain chemical stabilization methods may cause stormwater or soil pollution and should not be used. See WE-1, Wind Erosion Control.
 Management of construction traffic is subject to air quality control measures. Contact the local air quality management agency.
 Materials will likely need to be removed prior to final project grading and stabilization.  Use of this BMP may not be applicable to very short duration projects.

Implementation
General
Areas that are graded for construction vehicle transport and parking purposes are especially susceptible to erosion and dust. The exposed soil surface is continually disturbed, leaving no opportunity for vegetative stabilization. Such areas also tend to collect and transport runoff waters along their surfaces. During wet weather, they often become muddy quagmires that generate significant quantities of sediment that may pollute nearby streams or be transported offsite on the wheels of construction vehicles. Dirt roads can become so unstable during wet weather that they are virtually unusable.

Efficient construction road stabilization not only reduces onsite erosion but also can significantly speed onsite work, avoid instances of immobilized machinery and delivery vehicles, and generally improve site efficiency and working conditions during adverse weather Installation/Application Criteria
Permanent roads and parking areas should be paved as soon as possible after grading. As an alternative where construction will be phased, the early application of gravel or chemical stabilization may solve potential erosion and stability problems. Temporary gravel roadway should be considered during the rainy season and on slopes greater than 5%.

Temporary roads should follow the contour of the natural terrain to the maximum extent possible. Slope should not exceed 15%. Roadways should be carefully graded to drain transversely. Provide drainage swales on each side of the roadway in the case of a crowned section or one side in the case of a super elevated section. Simple gravel berms without a trench can also be used.

Installed inlets should be protected to prevent sediment laden water from entering the storm sewer system (SE-10, Storm Drain Inlet Protection). In addition, the following criteria should be considered.
 Road should follow topographic contours to reduce erosion of the roadway.  The roadway slope should not exceed 15%.
 Chemical stabilizers or water are usually required on gravel or dirt roads to prevent dust (WE-1, Wind Erosion Control).
 Properly grade roadway to prevent runoff from leaving the construction site.  Design stabilized access to support heaviest vehicles and equipment that will use it.

Stabilized Construction Roadway TC-2
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 Stabilize roadway using aggregate, asphalt concrete, or concrete based on longevity, required performance, and site conditions. The use of cold mix asphalt or asphalt concrete (AC) grindings for stabilized construction roadway is not allowed.  Coordinate materials with those used for stabilized construction entrance/exit points.  If aggregate is selected, place crushed aggregate over geotextile fabric to at least 12 in. depth.

A crushed aggregate greater than 3 in. but smaller than 6 in. should be used.

Costs
Gravel construction roads are moderately expensive, but cost is often balanced by reductions in construction delay. No additional costs for dust control on construction roads should be required above that needed to meet local air quality requirements.

References
Blueprint for a Clean Bay: Best Management Practices to Prevent Stormwater Pollution from Construction Related Activities; Santa Clara Valley Nonpoint Source Pollution Control Program, 1995.

Coastal Nonpoint Pollution Control Program; Program Development and Approval Guidance, Working Group, Working Paper; USEPA, April 1992.

Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992.

Stormwater Management of the Puget Sound Basin, Technical Manual, Publication #91-75, Washington State Department of Ecology, February 1992.

Stabilized Construction Roadway TC-2
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Virginia Erosion and Sedimentation Control Handbook, Virginia Department of Conservation and Recreation, Division of Soil and Water Conservation, 1991.

Water Quality Management Plan for the Lake Tahoe Region, Volume II, Handbook of Management Practices, Tahoe Regional Planning Agency, November 1988.

Entrance/Outlet Tire Wash TC-3
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Description and Purpose
A tire wash is an area located at stabilized construction access points to remove sediment from tires and under carriages and to prevent sediment from being transported onto public
roadways.

Suitable Applications
Tire washes may be used on construction sites where dirt and mud tracking onto public roads by construction vehicles may occur.

Limitations
 The tire wash requires a supply of wash water.
 A turnout or doublewide exit is required to avoid having entering vehicles drive through the wash area.
 Do not use where wet tire trucks leaving the site leave the road dangerously slick.

Implementation
 Incorporate with a stabilized construction entrance/exit.

See TC-1, Stabilized Construction Entrance/Exit.
 Construct on level ground when possible, on a pad of coarse aggregate greater than 3 in. but smaller than 6 in. A
geotextile fabric should be placed below the aggregate.  Wash rack should be designed and
constructed/manufactured for anticipated traffic loads.

Potential Alternatives
TC-1 Stabilized Construction Entrance/Exit
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Entrance/Outlet Tire Wash TC-3
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 Provide a drainage ditch that will convey the runoff from the wash area to a sediment trapping device. The drainage ditch should be of sufficient grade, width, and depth to carry the wash runoff.
 Use hoses with automatic shutoff nozzles to prevent hoses from being left on.  Require that all employees, subcontractors, and others that leave the site with mud caked tires and undercarriages to use the wash facility.
 Implement SC-7, Street Sweeping and Vacuuming, as needed.

Costs
Costs are low for installation of wash rack.

Coastal Nonpoint Pollution Control Program; Program Development and Approval Guidance, Working Group, Working Paper; USEPA, April 1992.

Manual of Standards of Erosion and Sediment Control Measures, Association of Bay Area Governments, May 1995.

Stormwater Quality Handbooks Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992.

Entrance/Outlet Tire Wash TC-3
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Water Conservation Practices NS-1
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Description and Purpose
Water conservation practices are activities that use water during the construction of a project in a manner that avoids causing erosion and the transport of pollutants offsite. These practices can reduce or eliminate non-stormwater discharges.

Suitable Applications
Water conservation practices are suitable for all construction sites where water is used, including piped water, metered water, trucked water, and water from a reservoir.

Limitations
 None identified.

Implementation
 Keep water equipment in good working condition.
 Stabilize water truck filling area.
 Repair water leaks promptly.
 Washing of vehicles and equipment on the construction site is discouraged.
 Avoid using water to clean construction areas. If water must be used for cleaning or surface preparation, surface should be swept and vacuumed first to remove dirt. This will minimize amount of water required.

Categories
EC Erosion Control 
SE Sediment Control 
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease
Organics

Potential Alternatives
None
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Water Conservation Practices NS-1
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 Direct construction water runoff to areas where it can soak into the ground or be collected and used.
 Authorized non-stormwater discharges to the storm drain system, channels, or receiving waters are acceptable with the implementation of appropriate BMPs.  Lock water tank valves to prevent unauthorized use.

Costs
The cost is small to none compared to the benefits of conserving water.

Inspection and Maintenance
 Inspect and verify that activity based BMPs are in place prior to the commencement of authorized non-stormwater discharges.
 Inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges are occuring.
 Repair water equipment as needed to prevent unintended discharges. Water trucks
Water reservoirs (water buffalos)
Irrigation systems
Hydrant connections
References
Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Paving and Grinding Operations NS-3
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Description and Purpose
Prevent or reduce the discharge of pollutants from paving operations, using measures to prevent runon and runoff
pollution, properly disposing of wastes, and training employees and subcontractors.

The General Permit incorporates Numeric Action Levels (NAL) for pH and turbidity (see Section 2 of this handbook to determine your project’s risk level and if you are subject to these requirements).

Many types of construction materials associated with paving and grinding operations, including mortar, concrete, and cement and their associated wastes have basic chemical
properties that can raise pH levels outside of the permitted range. Additional care should be taken when managing these materials to prevent them from coming into contact with stormwater flows, which could lead to exceedances of the General Permit requirements.

Suitable Applications
These procedures are implemented where paving, surfacing, resurfacing, or sawcutting, may pollute stormwater runoff or discharge to the storm drain system or watercourses.

Limitations
 Paving opportunities may be limited during wet weather.

Discharges of freshly paved surfaces may raise pH to
environmentally harmful levels and trigger permit
violations.

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals
Bacteria
Oil and Grease 
Organics

Potential Alternatives
None
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Implementation
General
 Avoid paving during the wet season when feasible.
 Reschedule paving and grinding activities if rain is forecasted.  Train employees and sub-contractors in pollution prevention and reduction.  Store materials away from drainage courses to prevent stormwater runon (see WM-1, Material Delivery and Storage).
 Protect drainage courses, particularly in areas with a grade, by employing BMPs to divert runoff or to trap and filter sediment.
 Stockpile material removed from roadways away from drain inlets, drainage ditches, and watercourses. These materials should be stored consistent with WM-3, Stockpile Management.
 Disposal of PCC (Portland cement concrete) and AC (asphalt concrete) waste should be in conformance with WM-8, Concrete Waste Management.

Saw Cutting, Grinding, and Pavement Removal
 Shovel or vacuum saw-cut slurry and remove from site. Cover or barricade storm drains during saw cutting to contain slurry.
 When paving involves AC, the following steps should be implemented to prevent the discharge of grinding residue, uncompacted or loose AC, tack coats, equipment cleaners, or unrelated paving materials:
AC grindings, pieces, or chunks used in embankments or shoulder backing should not be allowed to enter any storm drains or watercourses. Install inlet protection and perimeter controls until area is stabilized (i.e. cutting, grinding or other removal activities are complete and loose material has been properly removed and disposed of)or permanent controls are in place. Examples of temporary perimeter controls can be found in EC-9, Earth Dikes and Drainage Swales; SE-1, Silt Fence; SE-5, Fiber Rolls, or SE-13 Compost Socks and Berms
Collect and remove all broken asphalt and recycle when practical. Old or spilled asphalt should be recycled or disposed of properly.
 Do not allow saw-cut slurry to enter storm drains or watercourses. Residue from grinding operations should be picked up by a vacuum attachment to the grinding machine, or by sweeping, should not be allowed to flow across the pavement, and should not be left on the surface of the pavement. See also WM-8, Concrete Waste Management, and WM-10, Liquid Waste Management.
 Pavement removal activities should not be conducted in the rain.  Collect removed pavement material by mechanical or manual methods. This material may be recycled for use as shoulder backing or base material.

Paving and Grinding Operations NS-3
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 If removed pavement material cannot be recycled, transport the material back to an approved storage site.

Asphaltic Concrete Paving
 If paving involves asphaltic cement concrete, follow these steps:
Do not allow sand or gravel placed over new asphalt to wash into storm drains, streets, or creeks. Vacuum or sweep loose sand and gravel and properly dispose of this waste by referring to WM-5, Solid Waste Management.
Old asphalt should be disposed of properly. Collect and remove all broken asphalt from the site and recycle whenever possible.

Portland Cement Concrete Paving
 Do not wash sweepings from exposed aggregate concrete into a storm drain system. Collect waste materials by dry methods, such as sweeping or shoveling, and return to aggregate base stockpile or dispose of properly. Allow aggregate rinse to settle. Then, either allow rinse water to dry in a temporary pit as described in WM-8, Concrete Waste Management, or pump the water to the sanitary sewer if authorized by the local wastewater authority.

Sealing Operations
 During chip seal application and sweeping operations, petroleum or petroleum covered aggregate should not be allowed to enter any storm drain or water courses. Apply temporary perimeter controls until structure is stabilized (i.e. all sealing operations are complete and cured and loose materials have been properly removed and disposed).  Inlet protection (SE-10, Storm Drain Inlet Protection) should be used during application of seal coat, tack coat, slurry seal, and fog seal.
 Seal coat, tack coat, slurry seal, or fog seal should not be applied if rainfall is predicted to occur during the application or curing period.

Paving Equipment
 Leaks and spills from paving equipment can contain toxic levels of heavy metals and oil and grease. Place drip pans or absorbent materials under paving equipment when not in use.

Clean up spills with absorbent materials and dispose of in accordance with the applicable regulations. See NS-10, Vehicle and Equipment Maintenance, WM-4, Spill Prevention and Control, and WM-10, Liquid Waste Management.
 Substances used to coat asphalt transport trucks and asphalt spreading equipment should not contain soap and should be non-foaming and non-toxic.  Paving equipment parked onsite should be parked over plastic to prevent soil contamination.
 Clean asphalt coated equipment offsite whenever possible. When cleaning dry, hardened asphalt from equipment, manage hardened asphalt debris as described in WM-5, Solid Waste Management. Any cleaning onsite should follow NS-8, Vehicle and Equipment Cleaning.

Paving and Grinding Operations NS-3
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Thermoplastic Striping
 Thermoplastic striper and pre-heater equipment shutoff valves should be inspected to ensure that they are working properly to prevent leaking thermoplastic from entering drain inlets, the stormwater drainage system, or watercourses.  Pre-heaters should be filled carefully to prevent splashing or spilling of hot thermoplastic.

Leave six inches of space at the top of the pre-heater container when filling thermoplastic to allow room for material to move.
 Do not pre-heat, transfer, or load thermoplastic near drain inlets or watercourses.  Clean truck beds daily of loose debris and melted thermoplastic. When possible, recycle thermoplastic material.

Raised/Recessed Pavement Marker Application and Removal  Do not transfer or load bituminous material near drain inlets, the stormwater drainage system, or watercourses.
 Melting tanks should be loaded with care and not filled to beyond six inches from the top to leave room for splashing.
 When servicing or filling melting tanks, ensure all pressure is released before removing lids to avoid spills.
 On large-scale projects, use mechanical or manual methods to collect excess bituminous material from the roadway after removal of markers.

Costs
 All of the above are low cost measures.

Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of paving and grinding operations.
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Sample stormwater runoff required by the General Permit.  Keep ample supplies of drip pans or absorbent materials onsite.  Inspect and maintain machinery regularly to minimize leaks and drips.

Paving and Grinding Operations NS-3
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Hot Mix Asphalt-Paving Handbook AC 150/5370-14, Appendix I, U.S. Army Corps of Engineers, July 1991.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

Illicit Connection/Discharge NS-6
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Description and Purpose
Procedures and practices designed for construction contractors to recognize illicit connections or illegally dumped or discharged materials on a construction site and report
incidents.

Suitable Applications
This best management practice (BMP) applies to all
construction projects. Illicit connection/discharge and reporting is applicable anytime an illicit connection or discharge is discovered, or illegally dumped material is found on the construction site.

Limitations
Illicit connections and illegal discharges or dumping, for the purposes of this BMP, refer to discharges and dumping caused by parties other than the contractor. If pre-existing hazardous materials or wastes are known to exist onsite, they should be identified in the SWPPP and handled as set forth in the SWPPP.

Implementation
Planning
 Review the SWPPP. Pre-existing areas of contamination should be identified and documented in the SWPPP.
 Inspect site before beginning the job for evidence of illicit connections, illegal dumping or discharges. Document any pre-existing conditions and notify the owner.

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment
Nutrients 
Trash 
Metals 
Bacteria 
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Illicit Connection/Discharge NS-6
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 Inspect site regularly during project execution for evidence of illicit connections, illegal dumping or discharges.
 Observe site perimeter for evidence for potential of illicitly discharged or illegally dumped material, which may enter the job site.

Identification of Illicit Connections and Illegal Dumping or Discharges  General – unlabeled and unidentifiable material should be treated as hazardous.  Solids - Look for debris, or rubbish piles. Solid waste dumping often occurs on roadways with light traffic loads or in areas not easily visible from the traveled way.  Liquids - signs of illegal liquid dumping or discharge can include:
Visible signs of staining or unusual colors to the pavement or surrounding adjacent soils
Pungent odors coming from the drainage systems
Discoloration or oily substances in the water or stains and residues detained within ditches, channels or drain boxes
Abnormal water flow during the dry weather season
 Urban Areas - Evidence of illicit connections or illegal discharges is typically detected at storm drain outfall locations or at manholes. Signs of an illicit connection or illegal discharge can include:
Abnormal water flow during the dry weather season
Unusual flows in sub drain systems used for dewatering Pungent odors coming from the drainage systems
Discoloration or oily substances in the water or stains and residues detained within ditches, channels or drain boxes
Excessive sediment deposits, particularly adjacent to or near active offsite construction projects
 Rural Areas - Illicit connections or illegal discharges involving irrigation drainage ditches are detected by visual inspections. Signs of an illicit discharge can include:
Abnormal water flow during the non-irrigation season
Non-standard junction structures
Broken concrete or other disturbances at or near junction structures Reporting
Notify the owner of any illicit connections and illegal dumping or discharge incidents at the time of discovery. For illicit connections or discharges to the storm drain system, notify the local stormwater management agency. For illegal dumping, notify the local law enforcement agency.

Cleanup and Removal
The responsibility for cleanup and removal of illicit or illegal dumping or discharges will vary by location. Contact the local stormwater management agency for further information.

Illicit Connection/Discharge NS-6
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Costs
Costs to look for and report illicit connections and illegal discharges and dumping are low. The best way to avoid costs associated with illicit connections and illegal discharges and dumping is to keep the project perimeters secure to prevent access to the site, to observe the site for vehicles that should not be there, and to document any waste or hazardous materials that exist onsite before taking possession of the site.

Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.  Inspect the site regularly to check for any illegal dumping or discharge.  Prohibit employees and subcontractors from disposing of non-job-related debris or materials at the construction site.
 Notify the owner of any illicit connections and illegal dumping or discharge incidents at the time of discovery.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992.

Potable Water/Irrigation NS-7
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Description and Purpose
Potable Water/Irrigation consists of practices and procedures to manage the discharge of potential pollutants generated during discharges from irrigation water lines, landscape irrigation, lawn or garden watering, planned and unplanned discharges from potable water sources, water line flushing, and hydrant flushing.

Suitable Applications
Implement this BMP whenever potable water or irrigation water discharges occur at or enter a construction site.

Limitations
None identified.

Implementation
 Direct water from offsite sources around or through a construction site, where feasible, in a way that minimizes contact with the construction site.
 Discharges from water line flushing should be reused for landscaping purposes where feasible.
 Shut off the water source to broken lines, sprinklers, or valves as soon as possible to prevent excess water flow.  Protect downstream stormwater drainage systems and
watercourses from water pumped or bailed from trenches
excavated to repair water lines.

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients 
Trash
Metals 
Bacteria
Oil and Grease
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Potable Water/Irrigation NS-7
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 Inspect irrigated areas within the construction limits for excess watering. Adjust watering times and schedules to ensure that the appropriate amount of water is being used and to minimize runoff. Consider factors such as soil structure, grade, time of year, and type of plant material in determining the proper amounts of water for a specific area.

Costs
Cost to manage potable water and irrigation are low and generally considered to be a normal part of related activities.

Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.  Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges occur.
 Repair broken water lines as soon as possible.
 Inspect irrigated areas regularly for signs of erosion and/or discharge.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992.

Vehicle and Equipment Cleaning NS-8
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Description and Purpose
Vehicle and equipment cleaning procedures and practices eliminate or reduce the discharge of pollutants to stormwater from vehicle and equipment cleaning operations. Procedures and practices include but are not limited to: using offsite facilities; washing in designated, contained areas only; eliminating discharges to the storm drain by infiltrating the wash water; and training employees and subcontractors in proper cleaning procedures.

Suitable Applications
These procedures are suitable on all construction sites where vehicle and equipment cleaning is performed.

Limitations
Even phosphate-free, biodegradable soaps have been shown to be toxic to fish before the soap degrades. Sending
vehicles/equipment offsite should be done in conjunction with TC-1, Stabilized Construction Entrance/Exit.

Implementation
Other options to washing equipment onsite include contracting with either an offsite or mobile commercial washing business.

These businesses may be better equipped to handle and dispose of the wash waters properly. Performing this work offsite can also be economical by eliminating the need for a separate washing operation onsite.

If washing operations are to take place onsite, then:

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients 
Trash
Metals
Bacteria
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Vehicle and Equipment Cleaning NS-8
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 Use phosphate-free, biodegradable soaps.
 Educate employees and subcontractors on pollution prevention measures.  Do not permit steam cleaning onsite. Steam cleaning can generate significant pollutant concentrates.
 Cleaning of vehicles and equipment with soap, solvents or steam should not occur on the project site unless resulting wastes are fully contained and disposed of. Resulting wastes should not be discharged or buried and must be captured and recycled or disposed according to the requirements of WM-10, Liquid Waste Management or WM-6, Hazardous Waste Management, depending on the waste characteristics. Minimize use of solvents. Use of diesel for vehicle and equipment cleaning is prohibited.  All vehicles and equipment that regularly enter and leave the construction site must be cleaned offsite.
 When vehicle and equipment washing and cleaning must occur onsite, and the operation cannot be located within a structure or building equipped with appropriate disposal facilities, the outside cleaning area should have the following characteristics:
Located away from storm drain inlets, drainage facilities, or watercourses Paved with concrete or asphalt and bermed to contain wash waters and to prevent runon and runoff
Configured with a sump to allow collection and disposal of wash water No discharge of wash waters to storm drains or watercourses Used only when necessary
 When cleaning vehicles and equipment with water:
Use as little water as possible. High-pressure sprayers may use less water than a hose and should be considered
Use positive shutoff valve to minimize water usage
Facility wash racks should discharge to a sanitary sewer, recycle system or other approved discharge system and must not discharge to the storm drainage system, watercourses, or to groundwater
Costs
Cleaning vehicles and equipment at an offsite facility may reduce overall costs for vehicle and equipment cleaning by eliminating the need to provide similar services onsite. When onsite cleaning is needed, the cost to establish appropriate facilities is relatively low on larger, long- duration projects, and moderate to high on small, short-duration projects.

Vehicle and Equipment Cleaning NS-8
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Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.  Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges occur.
 Inspection and maintenance is minimal, although some berm repair may be necessary.  Monitor employees and subcontractors throughout the duration of the construction project to ensure appropriate practices are being implemented.
 Inspect sump regularly and remove liquids and sediment as needed.  Prohibit employees and subcontractors from washing personal vehicles and equipment on the construction site.

References
Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Swisher, R.D. Surfactant Biodegradation, Marcel Decker Corporation, 1987.

Vehicle and Equipment Fueling NS-9
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Description and Purpose
Vehicle equipment fueling procedures and practices are
designed to prevent fuel spills and leaks and reduce or eliminate contamination of stormwater. This can be
accomplished by using offsite facilities, fueling in designated areas only, enclosing or covering stored fuel, implementing spill controls, and training employees and subcontractors in proper fueling procedures.

Suitable Applications
These procedures are suitable on all construction sites where vehicle and equipment fueling takes place.

Limitations
Onsite vehicle and equipment fueling should only be used where it is impractical to send vehicles and equipment offsite for fueling. Sending vehicles and equipment offsite should be done in conjunction with TC-1, Stabilized Construction
Entrance/ Exit.

Implementation
 Use offsite fueling stations as much as possible. These businesses are better equipped to handle fuel and spills properly. Performing this work offsite can also be
economical by eliminating the need for a separate fueling area at a site.
 Discourage “topping-off” of fuel tanks.

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment
Nutrients
Trash
Metals
Bacteria
Oil and Grease 
Organics

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Vehicle and Equipment Fueling NS-9
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 Absorbent spill cleanup materials and spill kits should be available in fueling areas and on fueling trucks and should be disposed of properly after use.  Drip pans or absorbent pads should be used during vehicle and equipment fueling, unless the fueling is performed over an impermeable surface in a dedicated fueling area.  Use absorbent materials on small spills. Do not hose down or bury the spill. Remove the adsorbent materials promptly and dispose of properly.
 Avoid mobile fueling of mobile construction equipment around the site; rather, transport the equipment to designated fueling areas. With the exception of tracked equipment such as bulldozers and large excavators, most vehicles should be able to travel to a designated area with little lost time.
 Train employees and subcontractors in proper fueling and cleanup procedures.  When fueling must take place onsite, designate an area away from drainage courses to be used. Fueling areas should be identified in the SWPPP.  Dedicated fueling areas should be protected from stormwater runon and runoff and should be located at least 50 ft away from downstream drainage facilities and watercourses. Fueling must be performed on level-grade areas.
 Protect fueling areas with berms and dikes to prevent runon, runoff, and to contain spills.  Nozzles used in vehicle and equipment fueling should be equipped with an automatic shutoff to control drips. Fueling operations should not be left unattended.  Use vapor recovery nozzles to help control drips as well as air pollution where required by Air Quality Management Districts (AQMD).
 Federal, state, and local requirements should be observed for any stationary above ground storage tanks.

Costs
 All of the above measures are low cost except for the capital costs of above ground tanks that meet all local environmental, zoning, and fire codes.

Vehicle and Equipment Fueling NS-9
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 Immediately clean up spills and properly dispose of contaminated soil and cleanup materials.

Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance, Working Group Working Paper; USEPA, April 1992.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992.

Vehicle & Equipment Maintenance NS-10
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Description and Purpose
Prevent or reduce the contamination of stormwater resulting from vehicle and equipment maintenance by running a “dry and clean site”. The best option would be to perform
maintenance activities at an offsite facility. If this option is not available then work should be performed in designated areas only, while providing cover for materials stored outside, checking for leaks and spills, and containing and cleaning up spills immediately. Employees and subcontractors must be trained in proper procedures.

Suitable Applications
These procedures are suitable on all construction projects where an onsite yard area is necessary for storage and
maintenance of heavy equipment and vehicles.

Limitations
Onsite vehicle and equipment maintenance should only be used where it is impractical to send vehicles and equipment offsite for maintenance and repair. Sending vehicles/equipment offsite should be done in conjunction with TC-1, Stabilized Construction Entrance/Exit.

Outdoor vehicle or equipment maintenance is a potentially significant source of stormwater pollution. Activities that can contaminate stormwater include engine repair and service, changing or replacement of fluids, and outdoor equipment storage and parking (engine fluid leaks). For further
information on vehicle or equipment servicing, see NS-8, Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment
Nutrients 
Trash 
Metals
Bacteria
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Vehicle & Equipment Maintenance NS-10
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Vehicle and Equipment Cleaning, and NS-9, Vehicle and Equipment Fueling.

Implementation
 Use offsite repair shops as much as possible. These businesses are better equipped to handle vehicle fluids and spills properly. Performing this work offsite can also be economical by eliminating the need for a separate maintenance area.
 If maintenance must occur onsite, use designated areas, located away from drainage courses.

Dedicated maintenance areas should be protected from stormwater runon and runoff and should be located at least 50 ft from downstream drainage facilities and watercourses.  Drip pans or absorbent pads should be used during vehicle and equipment maintenance work that involves fluids, unless the maintenance work is performed over an impermeable surface in a dedicated maintenance area.
 Place a stockpile of spill cleanup materials where it will be readily accessible.  All fueling trucks and fueling areas are required to have spill kits and/or use other spill protection devices.
 Use adsorbent materials on small spills. Remove the absorbent materials promptly and dispose of properly.
 Inspect onsite vehicles and equipment daily at startup for leaks, and repair immediately.  Keep vehicles and equipment clean; do not allow excessive build-up of oil and grease.  Segregate and recycle wastes, such as greases, used oil or oil filters, antifreeze, cleaning solutions, automotive batteries, hydraulic and transmission fluids. Provide secondary containment and covers for these materials if stored onsite.  Train employees and subcontractors in proper maintenance and spill cleanup procedures.  Drip pans or plastic sheeting should be placed under all vehicles and equipment placed on docks, barges, or other structures over water bodies when the vehicle or equipment is planned to be idle for more than 1 hour.
 For long-term projects, consider using portable tents or covers over maintenance areas if maintenance cannot be performed offsite.
 Consider use of new, alternative greases and lubricants, such as adhesive greases, for chassis lubrication and fifth-wheel lubrication.
 Properly dispose of used oils, fluids, lubricants, and spill cleanup materials.  Do not place used oil in a dumpster or pour into a storm drain or watercourse.  Properly dispose of or recycle used batteries.
 Do not bury used tires.

Vehicle & Equipment Maintenance NS-10
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 Repair leaks of fluids and oil immediately.

Listed below is further information if you must perform vehicle or equipment maintenance onsite.

Safer Alternative Products
 Consider products that are less toxic or hazardous than regular products. These products are often sold under an “environmentally friendly” label.  Consider use of grease substitutes for lubrication of truck fifth-wheels. Follow manufacturers label for details on specific uses.
 Consider use of plastic friction plates on truck fifth-wheels in lieu of grease. Follow manufacturers label for details on specific uses.

Waste Reduction
Parts are often cleaned using solvents such as trichloroethylene, trichloroethane, or methylene chloride. Many of these cleaners are listed in California Toxic Rule as priority pollutants. These materials are harmful and must not contaminate stormwater. They must be disposed of as a hazardous waste. Reducing the number of solvents makes recycling easier and reduces hazardous waste management costs. Often, one solvent can perform a job as well as two different solvents. Also, if possible, eliminate or reduce the amount of hazardous materials and waste by substituting non-hazardous or less hazardous materials. For example, replace chlorinated organic solvents with non-chlorinated solvents. Non-chlorinated solvents like kerosene or mineral spirits are less toxic and less expensive to dispose of properly. Check the list of active ingredients to see whether it contains chlorinated solvents. The “chlor” term indicates that the solvent is chlorinated. Also, try substituting a wire brush for solvents to clean parts.

Recycling and Disposal
Separating wastes allows for easier recycling and may reduce disposal costs. Keep hazardous wastes separate, do not mix used oil solvents, and keep chlorinated solvents (like,- trichloroethane) separate from non-chlorinated solvents (like kerosene and mineral spirits).

Promptly transfer used fluids to the proper waste or recycling drums. Don’t leave full drip pans or other open containers lying around. Provide cover and secondary containment until these materials can be removed from the site.

Oil filters can be recycled. Ask your oil supplier or recycler about recycling oil filters.

Do not dispose of extra paints and coatings by dumping liquid onto the ground or throwing it into dumpsters. Allow coatings to dry or harden before disposal into covered dumpsters.

Store cracked batteries in a non-leaking secondary container. Do this with all cracked batteries, even if you think all the acid has drained out. If you drop a battery, treat it as if it is cracked.

Put it into the containment area until you are sure it is not leaking.

Costs
All of the above are low cost measures. Higher costs are incurred to setup and maintain onsite maintenance areas.

Vehicle & Equipment Maintenance NS-10
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Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.  Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges occur.
 Keep ample supplies of spill cleanup materials onsite.  Maintain waste fluid containers in leak proof condition.  Vehicles and equipment should be inspected on each day of use. Leaks should be repaired immediately, or the problem vehicle(s) or equipment should be removed from the project site.
 Inspect equipment for damaged hoses and leaky gaskets routinely. Repair or replace as needed.

Coastal Nonpoint Pollution Control Program; Program Development and Approval Guidance, Working Group, Working Paper; USEPA, April 1992.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Concrete Curing NS-12
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Description and Purpose
Concrete curing is used in the construction of structures such as bridges, retaining walls, pump houses, large slabs, and structured foundations. Concrete curing includes the use of both chemical and water methods.

Concrete and its associated curing materials have basic chemical properties that can raise the pH of water to levels outside of the permitted range. Discharges of stormwater and non-stormwater exposed to concrete during curing may have a high pH and may contain chemicals, metals, and fines. The General Permit incorporates Numeric Action Levels (NAL) for pH (see Section 2 of this handbook to determine your project’s risk level and if you are subject to these requirements).

Proper procedures and care should be taken when managing concrete curing materials to prevent them from coming into contact with stormwater flows, which could result in a high pH discharge.

Suitable Applications
Suitable applications include all projects where Portland Cement Concrete (PCC) and concrete curing chemicals are placed where they can be exposed to rainfall, runoff from other areas, or where runoff from the PCC will leave the site.

Limitations
 Runoff contact with concrete waste can raise pH levels in the water to environmentally harmful levels and trigger permit violations.

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals 
Bacteria
Oil and Grease 
Organics

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Concrete Curing NS-12
August 2023 CASQA Stormwater BMP Handbook 2 of 3
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Implementation
Chemical Curing
 Avoid over spray of curing compounds.
 Minimize the drift by applying the curing compound close to the concrete surface. Apply an amount of compound that covers the surface but does not allow any runoff of the compound.  Use proper storage and handling techniques for concrete curing compounds. Refer to WM- 1, Material Delivery and Storage.
 Protect drain inlets prior to the application of curing compounds.  Refer to WM-4, Spill Prevention and Control.

Water Curing for Bridge Decks, Retaining Walls, and other Structures  Direct cure water away from inlets and watercourses to collection areas for evaporation or other means of removal in accordance with all applicable permits. See WM-8 Concrete Waste Management.
 Collect cure water at the top of slopes and transport to a concrete waste management area in a non-erosive manner. See EC-9 Earth Dikes and Drainage Swales, EC-10, Velocity Dissipation Devices, and EC-11, Slope Drains.
 Utilize wet blankets or a similar method that maintains moisture while minimizing the use and possible discharge of water.

Education  Educate employees, subcontractors, and suppliers on proper concrete curing techniques to prevent contact with discharge as described herein.
 Arrange for the QSP or the appropriately trained contractor’s superintendent or representative to oversee and enforce concrete curing procedures.

Costs
All of the above measures are generally low cost.

Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities.
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges occur.
 Sample non-stormwater discharges and stormwater runoff that contacts uncured and partially cured concrete as required by the General Permit.

Concrete Curing NS-12
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 Ensure that employees and subcontractors implement appropriate measures for storage, handling, and use of curing compounds.
 Inspect cure containers and spraying equipment for leaks.

References
Blue Print for a Clean Bay-Construction-Related Industries: Best Management Practices for Stormwater Pollution Prevention; Santa Clara Valley Non-Point Source Pollution Control Program, 1992.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992.

Erosion and Sediment Control Manual, Oregon Department of Environmental Quality, February 2005.

Concrete Finishing NS-13
August 2023 CASQA Stormwater BMP Handbook 1 of 3
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Description and Purpose
Concrete finishing methods are used for bridge deck
rehabilitation, paint removal, curing compound removal, and final surface finish appearances. Methods include sand blasting, shot blasting, grinding, or high-pressure water blasting. Stormwater and non-stormwater exposed to concrete finishing by-products may have a high pH and may contain chemicals, metals, and fines. Proper procedures and
implementation of appropriate BMPs can minimize the impact that concrete-finishing methods may have on stormwater and non-stormwater discharges.

The General Permit incorporates Numeric Action Levels (NAL) for pH (see Section 2 of this handbook to determine your project’s risk level and if you are subject to these requirements).

Concrete and its associated curing materials have basic chemical properties that can raise pH levels outside of the permitted range. Additional care should be taken when
managing these materials to prevent them from coming into contact with stormwater flows, which could lead to exceedances of the General Permit requirements.

Suitable Applications
These procedures apply to all construction locations where concrete finishing operations are performed.

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals 
Bacteria
Oil and Grease
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Concrete Finishing NS-13
August 2023 CASQA Stormwater BMP Handbook 2 of 3
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Limitations
 Runoff contact with concrete waste can raise pH levels in the water to environmentally harmful levels and trigger permit violations.

Implementation
 Collect and properly dispose of water from high-pressure water blasting operations.  Collect contaminated water from blasting operations at the top of slopes. Transport or dispose of contaminated water while using BMPs such as those for erosion control. Refer to EC-9, Earth Dikes and Drainage Swales, EC-10, Velocity Dissipation Devices, and EC-11, Slope Drains.
 Direct water from blasting operations away from inlets and watercourses to collection areas for infiltration or other means of removal (dewatering). Refer to NS-2 Dewatering Operations.
 Protect inlets during sandblasting operations. Refer to SE-10, Storm Drain Inlet Protection.  Refer to WM-8, Concrete Waste Management for disposal of concrete debris.  Minimize the drift of dust and blast material as much as possible by keeping the blasting nozzle close to the surface.
 When blast residue contains a potentially hazardous waste, refer to WM-6, Hazardous Waste Management.

Education
 Educate employees, subcontractors, and suppliers on proper concrete finishing techniques to prevent contact with discharge as described herein.
 Arrange for the QSP or the appropriately trained contractor’s superintendent or representative to oversee and enforce concrete finishing procedures.

Costs
These measures are generally of low cost.

Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities.
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Inspect BMPs subject to non-stormwater discharges daily while non-stormwater discharges occur.
 Sample non-stormwater discharges and stormwater runoff that contacts concrete dust and debris as required by the General Permit.

Concrete Finishing NS-13
August 2023 CASQA Stormwater BMP Handbook 3 of 3
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 Sweep or vacuum up debris from sandblasting at the end of each shift.  At the end of each work shift, remove and contain liquid and solid waste from containment structures, if any, and from the general work area.
 Inspect containment structures for damage prior to use and prior to onset of forecasted rain.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Management for Construction Activities, Developing Pollution Prevention Plans and Best Management Practices, EPA 832-R-92005; USEPA, April 1992.

Material Delivery and Storage WM-1
August 2023 CASQA Stormwater BMP Handbook 1 of 5
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Description and Purpose
Prevent, reduce, or eliminate the discharge of pollutants from material delivery and storage to the stormwater system or watercourses by minimizing the storage of hazardous materials onsite, storing materials in watertight containers and/or a completely enclosed designated area, installing secondary containment, conducting regular inspections, and training employees and subcontractors.

This best management practice covers only material delivery and storage. For other information on materials, see WM-2, Material Use, or WM-4, Spill Prevention and Control. For information on wastes, see the waste management BMPs in this section.

Suitable Applications
These procedures are suitable for use at all construction sites with delivery and storage of the following materials:
 Soil stabilizers and binders
 Pesticides and herbicides
 Fertilizers
 Detergents
 Plaster
 Petroleum products such as fuel, oil, and grease
Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients 
Trash 
Metals 
Bacteria
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Material Delivery and Storage WM-1
August 2023 CASQA Stormwater BMP Handbook 2 of 5
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 Asphalt and concrete components
 Hazardous chemicals such as acids, lime, glues, adhesives, paints, solvents, and curing compounds
 Concrete compounds
 Other materials that may be detrimental if released to the environment Limitations
 Space limitation may preclude indoor storage.
 Storage sheds often must meet building and fire code requirements.

Implementation
The following steps should be taken to minimize risk:
 Chemicals must be stored in water tight containers with appropriate secondary containment or in a storage shed.
 When a material storage area is located on bare soil, the area should be lined and bermed.  Use containment pallets or other practical and available solutions, such as storing materials within newly constructed buildings or garages, to meet material storage requirements.  Stack erodible landscape material on pallets and cover when not in use.  Contain all fertilizers and other landscape materials when not in use.  Temporary storage areas should be located away from vehicular traffic.  Material Safety Data Sheets (MSDS) should be available on-site for all materials stored that have the potential to effect water quality.
 Construction site areas should be designated for material delivery and storage.  Material delivery and storage areas should be located away from waterways, if possible. Avoid transport near drainage paths or waterways.
Surround with earth berms or other appropriate containment BMP. See EC-9, Earth Dikes and Drainage Swales.
Place in an area that will be paved.
 Storage of reactive, ignitable, or flammable liquids must comply with the fire codes of your area. Contact the local Fire Marshal to review site materials, quantities, and proposed storage area to determine specific requirements. See the Flammable and Combustible Liquid Code, NFPA30.
 An up to date inventory of materials delivered and stored onsite should be kept.

Material Delivery and Storage WM-1
August 2023 CASQA Stormwater BMP Handbook 3 of 5
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 Hazardous materials storage onsite should be minimized.  Hazardous materials should be handled as infrequently as possible.  Keep ample spill cleanup supplies appropriate for the materials being stored. Ensure that cleanup supplies are in a conspicuous, labeled area.
 Employees and subcontractors should be trained on the proper material delivery and storage practices.
 Employees trained in emergency spill cleanup procedures must be present when dangerous materials or liquid chemicals are unloaded.
 If significant residual materials remain on the ground after construction is complete, properly remove and dispose of materials and any contaminated soil. See WM-7, Contaminated Soil Management. If the area is to be paved, pave as soon as materials are removed to stabilize the soil.

Material Storage Areas and Practices
 Liquids, petroleum products, and substances listed in 40 CFR Parts 110, 117, or 302 should be stored in approved containers and drums and should not be overfilled. Containers and drums should be placed in temporary containment facilities for storage.  A temporary containment facility should provide for a spill containment volume able to contain precipitation from a 25-year storm event, plus the greater of 10% of the aggregate volume of all containers or 100% of the capacity of the largest container within its boundary, whichever is greater.
 A temporary containment facility should be impervious to the materials stored therein for a minimum contact time of 72 hours.
 A temporary containment facility should be maintained free of accumulated rainwater and spills. In the event of spills or leaks, accumulated rainwater and spills should be collected and placed into drums. These liquids should be handled as a hazardous waste unless testing determines them to be non-hazardous. All collected liquids or non-hazardous liquids should be sent to an approved disposal site.
 Sufficient separation should be provided between stored containers to allow for spill cleanup and emergency response access.
 Incompatible materials, such as chlorine and ammonia, should not be stored in the same temporary containment facility.
 Materials should be covered prior to, and during rain events.  Materials should be stored in their original containers and the original product labels should be maintained in place in a legible condition. Damaged or otherwise illegible labels should be replaced immediately.

Material Delivery and Storage WM-1
August 2023 CASQA Stormwater BMP Handbook 4 of 5
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 Bagged and boxed materials should be stored on pallets and should not be allowed to accumulate on the ground. To provide protection from wind and rain throughout the rainy season, bagged and boxed materials should be covered during non-working days and prior to and during rain events.
 Stockpiles should be protected in accordance with WM-3, Stockpile Management.  Materials should be stored indoors within existing structures or completely enclosed storage sheds when available.
 Proper storage instructions should be posted at all times in an open and conspicuous location.
 An ample supply of appropriate spill clean up material should be kept near storage areas.  Also see WM-6, Hazardous Waste Management, for storing of hazardous wastes.

Material Delivery Practices
 Keep an accurate, up-to-date inventory of material delivered and stored onsite.  Arrange for employees trained in emergency spill cleanup procedures to be present when dangerous materials or liquid chemicals are unloaded.

Spill Cleanup
 Contain and clean up any spill immediately.
 Properly remove and dispose of any hazardous materials or contaminated soil if significant residual materials remain on the ground after construction is complete. See WM-7, Contaminated Soil Management.
 See WM-4, Spill Prevention and Control, for spills of chemicals and/or hazardous materials.  If spills or leaks of materials occur that are not contained and could discharge to surface waters, non-visible sampling of site discharge may be required. Refer to the General Permit or to your project specific Construction Site Monitoring Plan to determine if and where sampling is required.

Cost
 The largest cost of implementation may be in the construction of a materials storage area that is covered and provides secondary containment.

Material Delivery and Storage WM-1
August 2023 CASQA Stormwater BMP Handbook 5 of 5
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 Repair or replace perimeter controls, containment structures, covers, and liners as needed to maintain proper function.

Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance, Working Group Working Paper; USEPA, April 1992.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992.

Material Use WM-2
August 2023 CASQA Stormwater BMP Handbook 1 of 4
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Description and Purpose
Prevent or reduce the discharge of pollutants to the storm drain system or watercourses from material use by using alternative products, minimizing hazardous material use onsite, and training employees and subcontractors.

Suitable Applications
This BMP is suitable for use at all construction projects. These procedures apply when the following materials are used or prepared onsite:
 Pesticides and herbicides
 Fertilizers
 Detergents
 Petroleum products such as fuel, oil, and grease
 Asphalt and other concrete components
 Other hazardous chemicals such as acids, lime, glues, adhesives, paints, solvents, and curing compounds
 Other materials that may be detrimental if released to the environment
Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients 
Trash 
Metals 
Bacteria
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Material Use WM-2
August 2023 CASQA Stormwater BMP Handbook 2 of 4
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Limitations
Safer alternative building and construction products may not be available or suitable in every instance.

Implementation
The following steps should be taken to minimize risk:
 Minimize use of hazardous materials onsite.
 Follow manufacturer instructions regarding uses, protective equipment, ventilation, flammability, and mixing of chemicals.
 Train personnel who use pesticides. The California Department of Pesticide Regulation and county agricultural commissioners license pesticide dealers, certify pesticide applicators, and conduct onsite inspections.
 The preferred method of termiticide application is soil injection near the existing or proposed structure foundation/slab; however, if not feasible, soil drench application of termiticides should follow EPA label guidelines and the following recommendations (most of which are applicable to most pesticide applications):
 Do not treat soil that is water-saturated or frozen.
 Application shall not commence within 24-hours of a predicted precipitation event with a 40% or greater probability. Weather tracking must be performed on a daily basis prior to termiticide application and during the period of termiticide application.  Do not allow treatment chemicals to runoff from the target area. Apply proper quantity to prevent excess runoff. Provide containment for and divert stormwater from application areas using berms or diversion ditches during application.  Dry season: Do not apply within 10 feet of storm drains. Do not apply within 25 feet of aquatic habitats (such as, but not limited to, lakes; reservoirs; rivers; permanent streams; marshes or ponds; estuaries; and commercial fish farm ponds).  Wet season: Do not apply within 50 feet of storm drains or aquatic habitats (such as, but not limited to, lakes; reservoirs; rivers; permanent streams; marshes or ponds; estuaries; and commercial fish farm ponds) unless a vegetative buffer is present (if so, refer to dry season requirements).
 Do not make on-grade applications when sustained wind speeds are above 10 mph (at application site) at nozzle end height.
 Cover treatment site prior to a rain event in order to prevent run-off of the pesticide into non-target areas. The treated area should be limited to a size that can be backfilled and/or covered by the end of the work shift. Backfilling or covering of the treated area shall be done by the end of the same work shift in which the application is made.  The applicator must either cover the soil him/herself or provide written notification of the above requirement to the contractor on site and to the person commissioning the

Material Use WM-2
August 2023 CASQA Stormwater BMP Handbook 3 of 4
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application (if different than the contractor). If notice is provided to the contractor or the person commissioning the application, then they are responsible under the Federal Insecticide Fungicide, and Rodenticide Act (FIFRA) to ensure that: 1) if the concrete slab cannot be poured over the treated soil within 24 hours of application, the treated soil is covered with a waterproof covering (such as polyethylene sheeting), and 2) the treated soil is covered if precipitation is predicted to occur before the concrete slab is scheduled to be poured.
 Do not over-apply fertilizers, herbicides, and pesticides. Prepare only the amount needed.

Follow the recommended usage instructions. Over-application is expensive and environmentally harmful. Unless on steep slopes, till fertilizers into the soil rather than hydraulic application. Apply surface dressings in several smaller applications, as opposed to one large application, to allow time for infiltration and to avoid excess material being carried offsite by runoff. Do not apply these chemicals before predicted rainfall.  Train employees and subcontractors in proper material use.  Supply Material Safety Data Sheets (MSDS) for all materials.  Dispose of latex paint and paint cans, used brushes, rags, absorbent materials, and drop cloths, when thoroughly dry and are no longer hazardous, with other construction debris.  Do not remove the original product label; it contains important safety and disposal information. Use the entire product before disposing of the container.  Mix paint indoors or in a containment area. Never clean paintbrushes or rinse paint containers into a street, gutter, storm drain, or watercourse. Dispose of any paint thinners, residue, and sludge(s) that cannot be recycled, as hazardous waste.  For water-based paint, clean brushes to the extent practicable, and rinse to a drain leading to a sanitary sewer where permitted or contain for proper disposal off site. For oil-based paints, clean brushes to the extent practicable, and filter and reuse thinners and solvents.  Use recycled and less hazardous products when practical. Recycle residual paints, solvents, non-treated lumber, and other materials.
 Use materials only where and when needed to complete the construction activity. Use safer alternative materials as much as possible. Reduce or eliminate use of hazardous materials onsite when practical.
 Document the location, time, chemicals applied, and applicator’s name and qualifications.  Keep an ample supply of spill clean up material near use areas. Train employees in spill clean up procedures.
 Avoid exposing applied materials to rainfall and runoff unless sufficient time has been allowed for them to dry.
 Discontinue use of erodible landscape material within 2 days prior to a forecasted rain event and materials should be covered and/or bermed.

Material Use WM-2
August 2023 CASQA Stormwater BMP Handbook 4 of 4
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 Provide containment for material use areas such as masons’ areas or paint mixing/preparation areas to prevent materials/pollutants from entering stormwater.

Costs
All of the above are low cost measures.

Inspection and Maintenance
 Inspect and verify that activity-based BMPs are in place prior to the commencement of associated activities.
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Ensure employees and subcontractors throughout the job are using appropriate practices.

Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance, Working Group Working Paper; USEPA, April 1992.

Comments on Risk Assessments Risk Reduction Options for Cypermethrin: Docket No. OPP– 2005–0293; California Stormwater Quality Association (CASQA) letter to USEPA, 2006.Environmental Hazard and General Labeling for Pyrethroid Non-Agricultural Outdoor Products, EPA-HQ-OPP-2008-0331-0021; USEPA, 2008.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992.

Stockpile Management WM-3
August 2023 CASQA Stormwater BMP Handbook 1 of 3
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Description and Purpose
Stockpile management procedures and practices are designed to reduce or eliminate air and stormwater pollution from stockpiles of soil, soil amendments, sand, paving materials such as Portland cement concrete (PCC) rubble, asphalt concrete (AC), asphalt concrete rubble, aggregate base, aggregate sub base or pre-mixed aggregate, asphalt minder (so called “cold mix” asphalt), and pressure treated wood.

Suitable Applications
Implement in all projects that stockpile soil and other loose materials.

Limitations
 Plastic sheeting as a stockpile protection is temporary and hard to manage in windy conditions. Where plastic is used, consider use of plastic tarps with nylon reinforcement
which may be more durable than standard sheeting.
 Plastic sheeting can increase runoff volume due to lack of infiltration and potentially cause perimeter control failure.  Plastic sheeting breaks down faster in sunlight.
 The use of Plastic materials and photodegradable plastics should be avoided.

Implementation
Protection of stockpiles is a year-round requirement. To properly manage stockpiles:

Treat Categories
EC Erosion Control
SE Sediment Control 
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients 
Trash 
Metals 
Bacteria
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Stockpile Management WM-3
August 2023 CASQA Stormwater BMP Handbook 2 of 3
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 On larger sites, a minimum of 50 ft separation from concentrated flows of stormwater, drainage courses, and inlets is recommended.
 After 14 days of inactivity, a stockpile is non-active and requires further protection described below. All stockpiles are required to be protected as non-active stockpiles immediately if they are not scheduled to be used within 14 days.
 Protect all stockpiles from stormwater run-on using temporary perimeter sediment barriers such as compost berms (SE-13), temporary silt dikes (SE-12), fiber rolls (SE-5), silt fences (SE-1), sandbags (SE-8), gravel bags (SE-6), or biofilter bags (SE-14). Refer to the individual fact sheet for each of these controls for installation information.  Implement wind erosion control practices as appropriate on all stockpiled material. For specific information, see WE-1, Wind Erosion Control.
 Manage stockpiles of contaminated soil in accordance with WM-7, Contaminated Soil Management.
 Place bagged materials on pallets and under cover.
 Ensure that stockpile coverings are installed securely to protect from wind and rain.  Some plastic covers withstand weather and sunlight better than others. Select cover materials or methods based on anticipated duration of use.

Protection of Non-Active Stockpiles
A stockpile is considered non-active if it either is not used for 14 days or if it is scheduled not to be used for 14 days or more. Stockpiles need to be protected immediately if they are not scheduled to be used within 14 days. Non-active stockpiles of the identified materials should be protected as follows:

Soil stockpiles
 Soil stockpiles should be covered or protected with soil stabilization measures and a temporary perimeter sediment barrier at all times.
 Temporary vegetation should be considered for topsoil piles that will be stockpiled for extended periods.

Stockpiles of Portland cement concrete rubble, asphalt concrete, asphalt concrete rubble, aggregate base, or aggregate sub base
 Stockpiles should be covered and protected with a temporary perimeter sediment barrier at all times.

Stockpiles of “cold mix”
 Cold mix stockpiles should be placed on and covered with plastic sheeting or comparable material at all times and surrounded by a berm.

Stockpiles of fly ash, stucco, hydrated lime

Stockpile Management WM-3
August 2023 CASQA Stormwater BMP Handbook 3 of 3
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 Stockpiles of materials that may raise the pH of runoff (i.e., basic materials) should be covered with plastic and surrounded by a berm.

Stockpiles/Storage of treated wood
 Treated wood should be covered with plastic sheeting or comparable material at all times and surrounded by a berm.

Protection of Active Stockpiles
A stockpile is active when it is being used or is scheduled to be used within 14 days of the previous use. Active stockpiles of the identified materials should be protected as follows:
 All stockpiles should be covered and protected with a temporary linear sediment barrier prior to the onset of precipitation.
 Stockpiles of “cold mix” and treated wood, and basic materials should be placed on and covered with plastic sheeting or comparable material and surrounded by a berm prior to the onset of precipitation.
 The downstream perimeter of an active stockpile should be protected with a linear sediment barrier or berm and runoff should be diverted around or away from the stockpile on the upstream perimeter.

Costs
For cost information associated with stockpile protection refer to the individual erosion or sediment control BMP fact sheet considered for implementation (For example, refer to SE-1 Silt Fence for installation of silt fence around the perimeter of a stockpile.) Inspection and Maintenance
 Stockpiles must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 It may be necessary to inspect stockpiles covered with plastic sheeting more frequently during certain conditions (for example, high winds or extreme heat).  Repair and/or replace perimeter controls and covers as needed to keep them functioning properly.
 Sediment shall be removed when it reaches one-third of the barrier height.

References
Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Spill Prevention and Control WM-4
August 2023 CASQA Stormwater BMP Handbook 1 of 6
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Description and Purpose
Prevent or reduce the discharge of pollutants to drainage systems or watercourses from leaks and spills by reducing the chance for spills, stopping the source of spills, containing and cleaning up spills, properly disposing of spill materials, and training employees.

This best management practice covers only spill prevention and control. However, WM-1, Materials Delivery and Storage, and WM-2, Material Use, also contain useful information,
particularly on spill prevention. For information on wastes, see the waste management BMPs in this section.

Suitable Applications
This BMP is suitable for all construction projects. Spill control procedures are implemented anytime chemicals or hazardous substances are stored on the construction site, including the following materials:
 Soil stabilizers/binders
 Dust palliatives
 Herbicides
 Growth inhibitors
 Fertilizers
 Deicing/anti-icing chemicals
Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients 
Trash 
Metals 
Bacteria
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Spill Prevention and Control WM-4
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 Fuels
 Lubricants
 Other petroleum distillates
Limitations
 In some cases, it may be necessary to use a private spill cleanup company.  This BMP applies to spills caused by the contractor and subcontractors.  Procedures and practices presented in this BMP are general. Contractor should identify appropriate practices for the specific materials used or stored onsite Implementation
The following steps will help reduce the stormwater impacts of leaks and spills:

Education
 Be aware that different materials pollute in different amounts. Make sure that each employee knows what a “significant spill” is for each material they use, and what is the appropriate response for “significant” and “insignificant” spills.  Educate employees and subcontractors on potential dangers to humans and the environment from spills and leaks.
 Hold regular meetings to discuss and reinforce appropriate disposal procedures (incorporate into regular safety meetings).
 Establish a continuing education program to indoctrinate new employees.  Have contractor’s superintendent or representative oversee and enforce proper spill prevention and control measures.

General Measures
 To the extent that the work can be accomplished safely, spills of oil, petroleum products, substances listed under 40 CFR parts 110,117, and 302, and sanitary and septic wastes should be contained and cleaned up immediately.
 Store hazardous materials and wastes in covered containers and protect from vandalism.  Place a stockpile of spill cleanup materials where it will be readily accessible.  Train employees in spill prevention and cleanup.
 Designate responsible individuals to oversee and enforce control measures.  Spills should be covered and protected from stormwater runon during rainfall to the extent that it doesn’t compromise clean up activities.
 Do not bury or wash spills with water.

Spill Prevention and Control WM-4
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 Store and dispose of used clean up materials, contaminated materials, and recovered spill material that is no longer suitable for the intended purpose in conformance with the provisions in applicable BMPs.
 Do not allow water used for cleaning and decontamination to enter storm drains or watercourses. Collect and dispose of contaminated water in accordance with WM-10, Liquid Waste Management.
 Contain water overflow or minor water spillage and do not allow it to discharge into drainage facilities or watercourses.
 Place proper storage, cleanup, and spill reporting instructions for hazardous materials stored or used on the project site in an open, conspicuous, and accessible location.  Keep waste storage areas clean, well organized, and equipped with ample cleanup supplies as appropriate for the materials being stored. Perimeter controls, containment structures, covers, and liners should be repaired or replaced as needed to maintain proper function.

Cleanup
 Clean up leaks and spills immediately.
 Use a rag for small spills on paved surfaces, a damp mop for general cleanup, and absorbent material for larger spills. If the spilled material is hazardous, then the used cleanup materials are also hazardous and must be sent to either a certified laundry (rags) or disposed of as hazardous waste.
 Never hose down or bury dry material spills. Clean up as much of the material as possible and dispose of properly. See the waste management BMPs in this section for specific information.

Minor Spills
 Minor spills typically involve small quantities of oil, gasoline, paint, etc. which can be controlled by the first responder at the discovery of the spill.  Use absorbent materials on small spills rather than hosing down or burying the spill.  Absorbent materials should be promptly removed and disposed of properly.  Follow the practice below for a minor spill:
Contain the spread of the spill.
Recover spilled materials.
Clean the contaminated area and properly dispose of contaminated materials.

Semi-Significant Spills
 Semi-significant spills still can be controlled by the first responder along with the aid of other personnel such as laborers and the foreman, etc. This response may require the cessation of all other activities.

Spill Prevention and Control WM-4
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 Spills should be cleaned up immediately:
Contain spread of the spill.
Notify the project foreman immediately.
If the spill occurs on paved or impermeable surfaces, clean up using "dry" methods (absorbent materials, cat litter and/or rags). Contain the spill by encircling with absorbent materials and do not let the spill spread widely. If the spill occurs in dirt areas, immediately contain the spill by constructing an earthen dike. Dig up and properly dispose of contaminated soil. If the spill occurs during rain, cover spill with tarps or other material to prevent contaminating runoff.

Significant/Hazardous Spills
 For significant or hazardous spills that cannot be controlled by personnel in the immediate vicinity, the following steps should be taken:
Notify the local emergency response by dialing 911. In addition to 911, the contractor will notify the proper county officials. It is the contractor's responsibility to have all emergency phone numbers at the construction site.
Notify the Governor's Office of Emergency Services Warning Center, (916) 845-8911. For spills of federal reportable quantities, in conformance with the requirements in 40 CFR parts 110,119, and 302, the contractor should notify the National Response Center at (800) 424-8802.
Notification should first be made by telephone and followed up with a written report. The services of a spill’s contractor or a Haz-Mat team should be obtained immediately.

Construction personnel should not attempt to clean up until the appropriate and qualified staffs have arrived at the job site.
Other agencies which may need to be consulted include, but are not limited to, the Fire Department, the Public Works Department, the Coast Guard, the Highway Patrol, the City/County Police Department, Department of Toxic Substances, California Division of Oil and Gas, Cal/OSHA, etc.

Reporting
 Report significant spills to local agencies, such as the Fire Department; they can assist in cleanup.
 Federal regulations require that any significant oil spill into a water body or onto an adjoining shoreline be reported to the National Response Center (NRC) at 800-424-8802 (24 hours).

Use the following measures related to specific activities:

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Vehicle and Equipment Maintenance
 If maintenance must occur onsite, use a designated area and a secondary containment, located away from drainage courses, to prevent the runon of stormwater and the runoff of spills.
 Regularly inspect onsite vehicles and equipment for leaks and repair immediately  Check incoming vehicles and equipment (including delivery trucks, and employee and subcontractor vehicles) for leaking oil and fluids. Do not allow leaking vehicles or equipment onsite.
 Always use secondary containment, such as a drain pan or drop cloth, to catch spills or leaks when removing or changing fluids.
 Place drip pans or absorbent materials under paving equipment when not in use.  Use absorbent materials on small spills rather than hosing down or burying the spill.

Remove the absorbent materials promptly and dispose of properly.  Promptly transfer used fluids to the proper waste or recycling drums. Don’t leave full drip pans or other open containers lying around
 Oil filters disposed of in trashcans or dumpsters can leak oil and pollute stormwater. Place the oil filter in a funnel over a waste oil-recycling drum to drain excess oil before disposal.

Oil filters can also be recycled. Ask the oil supplier or recycler about recycling oil filters.  Store cracked batteries in a non-leaking secondary container. Do this with all cracked batteries even if you think all the acid has drained out. If you drop a battery, treat it as if it is cracked. Put it into the containment area until you are sure it is not leaking.

Vehicle and Equipment Fueling
 If fueling must occur onsite, use designate areas, located away from drainage courses, to prevent the runon of stormwater and the runoff of spills.  Discourage “topping off” of fuel tanks.
 Always use secondary containment, such as a drain pan, when fueling to catch spills/ leaks.

Costs
Prevention of leaks and spills is inexpensive. Treatment and/ or disposal of contaminated soil or water can be quite expensive.

Spill Prevention and Control WM-4
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 Inspect BMPs subject to non-stormwater discharge daily while non-stormwater discharges occur.
 Keep ample supplies of spill control and cleanup materials onsite, near storage, unloading, and maintenance areas.
 Update your spill prevention and control plan and stock cleanup materials as changes occur in the types of chemicals onsite.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992.

Solid Waste Management WM-5
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Description and Purpose
Solid waste management procedures and practices are designed to prevent or reduce the discharge of pollutants to stormwater from solid or construction waste by providing designated waste collection areas and containers, arranging for regular disposal, and training employees and subcontractors.

Suitable Applications
This BMP is suitable for construction sites where the following wastes are generated or stored:
 Solid waste generated from trees and shrubs removed
during land clearing, demolition of existing structures (rubble), and building construction
 Packaging materials including wood, paper, and plastic  Scrap or surplus building materials including scrap metals, rubber, plastic, glass pieces, and masonry products
 Domestic wastes including food containers such as beverage cans, coffee cups, paper bags, plastic wrappers, and
cigarettes
 Construction wastes including brick, mortar, timber, steel and metal scraps, pipe and electrical cuttings, non-
hazardous equipment parts, styrofoam and other materials used to transport and package construction materials
Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients 
Trash 
Metals 
Bacteria
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Solid Waste Management WM-5
August 2023 CASQA Stormwater BMP Handbook 2 of 4
Construction www.casqa.org
 Highway planting wastes, including vegetative material, plant containers, and packaging materials
Limitations
Temporary stockpiling of certain construction wastes may not necessitate stringent drainage related controls during the non-rainy season or in desert areas with low rainfall.

Implementation
The following steps will help keep a clean site and reduce stormwater pollution:
 Select designated waste collection areas onsite.
 Inform trash-hauling contractors that you will accept only watertight dumpsters for onsite use. Inspect dumpsters for leaks and repair any dumpster that is not watertight.  Locate containers in a covered area or in a secondary containment.  Provide an adequate number of containers with lids or covers that can be placed over the container to keep rain out or to prevent loss of wastes when it is windy.  Cover waste containers at the end of each work day and when it is raining.  Plan for additional containers and more frequent pickup during the demolition phase of construction.
 Collect site trash daily, especially during rainy and windy conditions.  Remove this solid waste promptly since erosion and sediment control devices tend to collect litter.
 Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris.
 Do not hose out dumpsters on the construction site. Leave dumpster cleaning to the trash hauling contractor.
 Arrange for regular waste collection before containers overflow.  Clean up immediately if a container does spill.
 Make sure that construction waste is collected, removed, and disposed of only at authorized disposal areas.

Education
 Have the contractor’s superintendent or representative oversee and enforce proper solid waste management procedures and practices.
 Instruct employees and subcontractors on identification of solid waste and hazardous waste.  Educate employees and subcontractors on solid waste storage and disposal procedures.

Solid Waste Management WM-5
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 Hold regular meetings to discuss and reinforce disposal procedures (incorporate into regular safety meetings).
 Require that employees and subcontractors follow solid waste handling and storage procedures.
 Prohibit littering by employees, subcontractors, and visitors.  Minimize production of solid waste materials wherever possible.

Collection, Storage, and Disposal
 Littering on the project site should be prohibited.
 To prevent clogging of the storm drainage system, litter and debris removal from drainage grates, trash racks, and ditch lines should be a priority.  Trash receptacles should be provided in the contractor’s yard, field trailer areas, and at locations where workers congregate for lunch and break periods.  Litter from work areas within the construction limits of the project site should be collected and placed in watertight dumpsters at least weekly, regardless of whether the litter was generated by the contractor, the public, or others. Collected litter and debris should not be placed in or next to drain inlets, stormwater drainage systems, or watercourses.  Dumpsters of sufficient size and number should be provided to contain the solid waste generated by the project.
 Full dumpsters should be removed from the project site and the contents should be disposed of by the trash hauling contractor.
 Construction debris and waste should be removed from the site biweekly or more frequently as needed.
 Construction material visible to the public should be stored or stacked in an orderly manner.  Stormwater runon should be prevented from contacting stored solid waste through the use of berms, dikes, or other temporary diversion structures or through the use of measures to elevate waste from site surfaces.
 Solid waste storage areas should be located at least 50 ft from drainage facilities and watercourses and should not be located in areas prone to flooding or ponding.  Except during fair weather, construction and highway planting waste not stored in watertight dumpsters should be securely covered from wind and rain by covering the waste with tarps or plastic.
 Segregate potentially hazardous waste from non-hazardous construction site waste.  Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris.

Solid Waste Management WM-5
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 For disposal of hazardous waste, see WM-6, Hazardous Waste Management. Have hazardous waste hauled to an appropriate disposal and/or recycling facility.  Salvage or recycle useful vegetation debris, packaging and surplus building materials when practical. For example, trees and shrubs from land clearing can be used as a brush barrier, or converted into wood chips, then used as mulch on graded areas. Wood pallets, cardboard boxes, and construction scraps can also be recycled.

Costs
All of the above are low cost measures.

References
Processes, Procedures and Methods to Control Pollution Resulting from All Construction Activity, 430/9-73-007, USEPA, 1973.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992.

Hazardous Waste Management WM-6
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Description and Purpose
Prevent or reduce the discharge of pollutants to stormwater from hazardous waste through proper material use, waste disposal, and training of employees and subcontractors.

Suitable Applications
This best management practice (BMP) applies to all construction projects. Hazardous waste management practices are
implemented on construction projects that generate waste from the use of:

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment
Nutrients 
Trash 
Metals 
Bacteria 
Oil and Grease 
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version. Petroleum Products Asphalt Products
Concrete Curing Compounds Pesticides
Palliatives Acids
Septic Wastes Paints
Stains Solvents
Wood Preservatives Roofing Tar
Any materials deemed a hazardous waste in California, Title 22 Division 4.5, or listed in 40 CFR Parts 110, 117, 261, or 302

Hazardous Waste Management WM-6
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In addition, sites with existing structures may contain wastes, which must be disposed of in accordance with federal, state, and local regulations. These wastes include:
 Sandblasting grit mixed with lead-, cadmium-, or chromium-based paints  Asbestos
 PCBs (particularly in older transformers)
Limitations
 Hazardous waste that cannot be reused or recycled must be disposed of by a licensed hazardous waste hauler.
 Nothing in this BMP relieves the contractor from responsibility for compliance with federal, state, and local laws regarding storage, handling, transportation, and disposal of hazardous wastes.
 This BMP does not cover aerially deposited lead (ADL) soils. For ADL soils refer to WM-7, Contaminated Soil Management.

Implementation
The following steps will help reduce stormwater pollution from hazardous wastes:

Material Use
 Wastes should be stored in sealed containers constructed of a suitable material and should be labeled as required by Title 22 CCR, Division 4.5 and 49 CFR Parts 172, 173, 178, and 179.  All hazardous waste should be stored, transported, and disposed as required in Title 22 CCR, Division 4.5 and 49 CFR 261-263.
 Waste containers should be stored in temporary containment facilities that should comply with the following requirements:
Temporary containment facility should provide for a spill containment volume equal to

1.5 times the volume of all containers able to contain precipitation from a 25-year storm event, plus the greater of 10% of the aggregate volume of all containers or 100% of the capacity of the largest tank within its boundary, whichever is greater. Temporary containment facility should be impervious to the materials stored there for a minimum contact time of 72 hours.
Temporary containment facilities should be maintained free of accumulated rainwater and spills. In the event of spills or leaks, accumulated rainwater and spills should be placed into drums after each rainfall. These liquids should be handled as a hazardous waste unless testing determines them to be non-hazardous. Non-hazardous liquids should be sent to an approved disposal site.
Sufficient separation should be provided between stored containers to allow for spill cleanup and emergency response access.

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Incompatible materials, such as chlorine and ammonia, should not be stored in the same temporary containment facility.
Throughout the rainy season, temporary containment facilities should be covered during non-working days, and prior to rain events. Covered facilities may include use of plastic tarps for small facilities or constructed roofs with overhangs.  Drums should not be overfilled, and wastes should not be mixed.  Unless watertight, containers of dry waste should be stored on pallets.  Do not over-apply herbicides and pesticides. Prepare only the amount needed. Follow the recommended usage instructions. Over application is expensive and environmentally harmful. Apply surface dressings in several smaller applications, as opposed to one large application. Allow time for infiltration and avoid excess material being carried offsite by runoff. Do not apply these chemicals just before it rains. People applying pesticides must be certified in accordance with federal and state regulations.  Paint brushes and equipment for water and oil-based paints should be cleaned within a contained area and should not be allowed to contaminate site soils, watercourses, or drainage systems. Waste paints, thinners, solvents, residues, and sludges that cannot be recycled or reused should be disposed of as hazardous waste. When thoroughly dry, latex paint and paint cans, used brushes, rags, absorbent materials, and drop cloths should be disposed of as solid waste.
 Do not clean out brushes or rinse paint containers into the dirt, street, gutter, storm drain, or stream. “Paint out” brushes as much as possible. Rinse water-based paints to the sanitary sewer. Filter and reuse thinners and solvents. Dispose of excess oil-based paints and sludge as hazardous waste.
 The following actions should be taken with respect to temporary contaminant:
Ensure that adequate hazardous waste storage volume is available. Ensure that hazardous waste collection containers are conveniently located. Designate hazardous waste storage areas onsite away from storm drains or watercourses and away from moving vehicles and equipment to prevent accidental spills. Minimize production or generation of hazardous materials and hazardous waste on the job site.
Use containment berms in fueling and maintenance areas and where the potential for spills is high.
Segregate potentially hazardous waste from non-hazardous construction site debris. Keep liquid or semi-liquid hazardous waste in appropriate containers (closed drums or similar) and under cover.

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Clearly label all hazardous waste containers with the waste being stored and the date of accumulation.
Place hazardous waste containers in secondary containment. Do not allow potentially hazardous waste materials to accumulate on the ground. Do not mix wastes.
Use all of the product before disposing of the container. Do not remove the original product label; it contains important safety and disposal information.

Waste Recycling Disposal
 Select designated hazardous waste collection areas onsite.  Hazardous materials and wastes should be stored in covered containers and protected from vandalism.
 Place hazardous waste containers in secondary containment.  Do not mix wastes, this can cause chemical reactions, making recycling impossible and complicating disposal.
 Recycle any useful materials such as used oil or water-based paint.  Make sure that toxic liquid wastes (used oils, solvents, and paints) and chemicals (acids, pesticides, additives, curing compounds) are not disposed of in dumpsters designated for construction debris.
 Arrange for regular waste collection before containers overflow.  Make sure that hazardous waste (e.g., excess oil-based paint and sludge) is collected, removed, and disposed of only at authorized disposal areas.

Disposal Procedures
 Waste should be disposed of by a licensed hazardous waste transporter at an authorized and licensed disposal facility or recycling facility utilizing properly completed Uniform Hazardous Waste Manifest forms.
 A Department of Health Services certified laboratory should sample waste to determine the appropriate disposal facility.
 Properly dispose of rainwater in secondary containment that may have mixed with hazardous waste.
 Attention is directed to "Hazardous Material", "Contaminated Material", and "Aerially Deposited Lead" of the contract documents regarding the handling and disposal of hazardous materials.

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Education
 Educate employees and subcontractors on hazardous waste storage and disposal procedures.  Educate employees and subcontractors on potential dangers to humans and the environment from hazardous wastes.
 Instruct employees and subcontractors on safety procedures for common construction site hazardous wastes.
 Instruct employees and subcontractors in identification of hazardous and solid waste.  Hold regular meetings to discuss and reinforce hazardous waste management procedures (incorporate into regular safety meetings).
 The contractor’s superintendent or representative should oversee and enforce proper hazardous waste management procedures and practices.
 Make sure that hazardous waste is collected, removed, and disposed of only at authorized disposal areas.
 Warning signs should be placed in areas recently treated with chemicals.  Place a stockpile of spill cleanup materials where it will be readily accessible.  If a container does spill, clean up immediately.

Costs
All of the above are low cost measures.

Inspection and Maintenance
 Inspect and verify that activity–based BMPs are in place prior to the commencement of associated activities. While activities associated with the BMP are under way, inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.  Inspect BMPs subject to non-stormwater discharge daily while non-stormwater discharges occur
 Hazardous waste should be regularly collected.
 A foreman or construction supervisor should monitor onsite hazardous waste storage and disposal procedures.
 Waste storage areas should be kept clean, well organized, and equipped with ample cleanup supplies as appropriate for the materials being stored.  Perimeter controls, containment structures, covers, and liners should be repaired or replaced as needed to maintain proper function.

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 Hazardous spills should be cleaned up and reported in conformance with the applicable Material Safety Data Sheet (MSDS) and the instructions posted at the project site.  The National Response Center, at (800) 424-8802, should be notified of spills of federal reportable quantities in conformance with the requirements in 40 CFR parts 110, 117, and 302. Also notify the Governors Office of Emergency Services Warning Center at (916) 845- 8911.
 A copy of the hazardous waste manifests should be provided.

Processes, Procedures and Methods to Control Pollution Resulting from All Construction Activity, 430/9-73-007, USEPA, 1973.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992.

Concrete Waste Management WM-8
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Description and Purpose
Prevent the discharge of pollutants to stormwater from
concrete waste by conducting washout onsite or offsite in a designated area, and by employee and subcontractor training.

The General Permit incorporates Numeric Action Levels (NAL) for pH (see Section 2 of this handbook to determine your project’s risk level and if you are subject to these requirements).

Many types of construction materials, including mortar, concrete, stucco, cement and block and their associated wastes have basic chemical properties that can raise pH levels outside of the permitted range. Additional care should be taken when managing these materials to prevent them from coming into contact with stormwater flows and raising pH to levels outside the accepted range.

Suitable Applications
Concrete waste management procedures and practices are
implemented on construction projects where:
 Concrete is used as a construction material or where
concrete dust and debris result from demolition activities.  Slurries containing Portland cement concrete (PCC) are generated, such as from saw cutting, coring, grinding,
grooving, and hydro-concrete demolition.
 Concrete trucks and other concrete-coated equipment are washed onsite.

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control 
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment 
Nutrients
Trash
Metals 
Bacteria
Oil and Grease
Organics

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Concrete Waste Management WM-8
August 2023 CASQA Stormwater BMP Handbook 2 of 7
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 Mortar-mixing stations exist.
 Stucco mixing and spraying.
 See also NS-8, Vehicle and Equipment Cleaning.

Limitations
 Offsite washout of concrete wastes may not always be possible.  Multiple washouts may be needed to assure adequate capacity and to allow for evaporation.

Implementation
The following steps will help reduce stormwater pollution from concrete wastes:
 Incorporate requirements for concrete waste management into material supplier and subcontractor agreements.
 Store dry and wet materials under cover, away from drainage areas. Refer to WM-1, Material Delivery and Storage for more information.
 Avoid mixing excess amounts of concrete.
 Perform washout of concrete trucks in designated areas only, where washout will not reach stormwater.
 Do not wash out concrete trucks into storm drains, open ditches, streets, streams or onto the ground. Trucks should always be washed out into designated facilities.  Do not allow excess concrete to be dumped onsite, except in designated areas.  For onsite washout:
On larger sites, it is recommended to locate washout areas at least 50 feet from storm drains, open ditches, or water bodies. Do not allow runoff from this area by constructing a temporary pit or bermed area large enough for liquid and solid waste. Washout wastes into the temporary washout where the concrete can set, be broken up, and then disposed properly.
Washouts shall be implemented in a manner that prevents leaching to underlying soils.

Washout containers must be water tight and washouts on or in the ground must be lined with a suitable impervious liner, typically a plastic type material.  Do not wash sweepings from exposed aggregate concrete into the street or storm drain.

Collect and return sweepings to aggregate base stockpile or dispose in the trash.  See typical concrete washout installation details at the end of this fact sheet.

Education
 Educate employees, subcontractors, and suppliers on the concrete waste management techniques described herein.

Concrete Waste Management WM-8
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 Arrange for contractor’s superintendent or representative to oversee and enforce concrete waste management procedures.
 Discuss the concrete management techniques described in this BMP (such as handling of concrete waste and washout) with the ready-mix concrete supplier before any deliveries are made.

Concrete Demolition Wastes
 Stockpile concrete demolition waste in accordance with BMP WM-3, Stockpile Management.  Dispose of or recycle hardened concrete waste in accordance with applicable federal, state or local regulations.

Concrete Slurry Wastes
 PCC and AC waste should not be allowed to enter storm drains or watercourses.  PCC and AC waste should be collected and disposed of or placed in a temporary concrete washout facility (as described in Onsite Temporary Concrete Washout Facility, Concrete Transit Truck Washout Procedures, below).
 A foreman or construction supervisor should monitor onsite concrete working tasks, such as saw cutting, coring, grinding and grooving to ensure proper methods are implemented.  Saw-cut concrete slurry should not be allowed to enter storm drains or watercourses.

Residue from grinding operations should be picked up by means of a vacuum attachment to the grinding machine or by sweeping. Saw cutting residue should not be allowed to flow across the pavement and should not be left on the surface of the pavement. See also NS-3, Paving and Grinding Operations; and WM-10, Liquid Waste Management.  Concrete slurry residue should be disposed in a temporary washout facility (as described in Onsite Temporary Concrete Washout Facility, Concrete Transit Truck Washout Procedures, below) and allowed to dry. Dispose of dry slurry residue in accordance with WM-5, Solid Waste Management.

Onsite Temporary Concrete Washout Facility, Transit Truck Washout Procedures
 Temporary concrete washout facilities should be located a minimum of 50 ft from storm drain inlets, open drainage facilities, and watercourses. Each facility should be located away from construction traffic or access areas to prevent disturbance or tracking.  A sign should be installed adjacent to each washout facility to inform concrete equipment operators to utilize the proper facilities.
 Temporary concrete washout facilities should be constructed above grade or below grade at the option of the contractor. Temporary concrete washout facilities should be constructed and maintained in sufficient quantity and size to contain all liquid and concrete waste generated by washout operations.

Concrete Waste Management WM-8
August 2023 CASQA Stormwater BMP Handbook 4 of 7
Construction www.casqa.org
 Temporary washout facilities should have a temporary pit or bermed areas of sufficient volume to completely contain all liquid and waste concrete materials generated during washout procedures.
 Temporary washout facilities should be lined to prevent discharge to the underlying ground or surrounding area.
 Washout of concrete trucks should be performed in designated areas only.  Only concrete from mixer truck chutes should be washed into concrete wash out.  Concrete washout from concrete pumper bins can be washed into concrete pumper trucks and discharged into designated washout area or properly disposed of or recycled offsite.  Once concrete wastes are washed into the designated area and allowed to harden, the concrete should be broken up, removed, and disposed of per WM-5, Solid Waste Management. Dispose of or recycle hardened concrete on a regular basis.  Temporary Concrete Washout Facility (Type Above Grade) Temporary concrete washout facility (type above grade) should be constructed as shown on the details at the end of this BMP, with a recommended minimum length and minimum width of 10 ft; however, smaller sites or jobs may only need a smaller washout facility. With any washout, always maintain a sufficient quantity and volume to contain all liquid and concrete waste generated by washout operations. Materials used to construct the washout area should conform to the provisions detailed in their respective BMPs (e.g., SE-8 Sandbag Barrier).
Plastic lining material should be a minimum of 10 mil in polyethylene sheeting and should be free of holes, tears, or other defects that compromise the impermeability of the material.
Alternatively, portable removable containers can be used as above grade concrete washouts. Also called a “roll-off”; this concrete washout facility should be properly sealed to prevent leakage and should be removed from the site and replaced when the container reaches 75% capacity.
 Temporary Concrete Washout Facility (Type Below Grade) Temporary concrete washout facilities (type below grade) should be constructed as shown on the details at the end of this BMP, with a recommended minimum length and minimum width of 10 ft. The quantity and volume should be sufficient to contain all liquid and concrete waste generated by washout operations. Lath and flagging should be commercial type.
Plastic lining material should be a minimum of 10 mil polyethylene sheeting and should be free of holes, tears, or other defects that compromise the impermeability of the material.

Concrete Waste Management WM-8
August 2023 CASQA Stormwater BMP Handbook 5 of 7
Construction www.casqa.org
The base of a washout facility should be free of rock or debris that may damage a plastic liner.

Removal of Temporary Concrete Washout Facilities
 When temporary concrete washout facilities are no longer required for the work, the hardened concrete should be removed and properly disposed or recycled in accordance with federal, state or local regulations. Materials used to construct temporary concrete washout facilities should be removed from the site of the work and properly disposed or recycled in accordance with federal, state or local regulations.
 Holes, depressions or other ground disturbance caused by the removal of the temporary concrete washout facilities should be backfilled and repaired.

Costs
All of the above are low cost measures. Roll-0ff concrete washout facilities can be more costly than other measures due to removal and replacement; however, provide a cleaner alternative to traditional washouts. The type of washout facility, size, and availability of materials will determine the cost of the washout.

Hardened concrete materials should be removed and properly disposed or recycled in accordance with federal, state or local regulations.
 Washout facilities must be cleaned, or new facilities must be constructed and ready for use once the washout is 75% full.
 Inspect washout facilities for damage (e.g. torn liner, evidence of leaks, signage, etc.). Repair all identified damage.

Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000, Updated March 2003.

Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992.

Concrete Waste Management WM-8
August 2023 CASQA Stormwater BMP Handbook 6 of 7
Construction www.casqa.org

Concrete Waste Management WM-8
August 2023 CASQA Stormwater BMP Handbook 7 of 7
Construction www.casqa.org

Sanitary/Septic Waste Management WM-9
August 2023 CASQA Stormwater BMP Handbook 1 of 3
Construction www.casqa.org

Description and Purpose
Proper sanitary and septic waste management prevent the discharge of pollutants to stormwater from sanitary and septic waste by providing convenient, well-maintained facilities, and arranging for regular service and disposal.

Suitable Applications
Sanitary septic waste management practices are suitable for use at all construction sites that use temporary or portable sanitary and septic waste systems.

Limitations
None identified.

Implementation
Sanitary or septic wastes should be treated or disposed of in accordance with state and local requirements. In many cases, one contract with a local facility supplier will be all that it takes to make sure sanitary wastes are properly disposed.

Storage and Disposal Procedures
 Temporary sanitary facilities should be located away from drainage facilities, watercourses, and from traffic
circulation. If site conditions allow, place portable facilities a minimum of 50 feet from drainage conveyances and
traffic areas. When subjected to high winds or risk of high winds, temporary sanitary facilities should be secured to prevent overturning.

Categories
EC Erosion Control
SE Sediment Control
TC Tracking Control
WE Wind Erosion Control
NS Non-Stormwater Management Control
WM Waste Management and Materials Pollution Control 
Legend:
 Primary Category
 Secondary Category
Targeted Constituents
Sediment
Nutrients 
Trash 
Metals
Bacteria 
Oil and Grease
Organics 

Potential Alternatives
None
If User/Subscriber modifies this fact sheet in any way, the CASQA name/logo and footer below must be removed from each page and not appear on the modified version.

Sanitary/Septic Waste Management WM-9
August 2023 CASQA Stormwater BMP Handbook 2 of 3
Construction www.casqa.org
 Temporary sanitary facilities must be equipped with containment to prevent discharge of pollutants to the stormwater drainage system of the receiving water.  Consider safety as well as environmental implications before placing temporary sanitary facilities.
 Wastewater should not be discharged or buried within the project site.  Sanitary and septic systems that discharge directly into sanitary sewer systems, where permissible, should comply with the local health agency, city, county, and sewer district requirements.
 Only reputable, licensed sanitary and septic waste haulers should be used.  Sanitary facilities should be located in a convenient location.  Temporary septic systems should treat wastes to appropriate levels before discharging.  If using an onsite disposal system (OSDS), such as a septic system, local health agency requirements must be followed.
 Temporary sanitary facilities that discharge to the sanitary sewer system should be properly connected to avoid illicit discharges.
 Sanitary and septic facilities should be maintained in good working order by a licensed service.
 Regular waste collection by a licensed hauler should be arranged before facilities overflow.  If a spill does occur from a temporary sanitary facility, follow federal, state and local regulations for containment and clean-up.

Education
 Educate employees, subcontractors, and suppliers on sanitary and septic waste storage and disposal procedures.
 Educate employees, subcontractors, and suppliers of potential dangers to humans and the environment from sanitary and septic wastes.
 Instruct employees, subcontractors, and suppliers in identification of sanitary and septic waste.
 Hold regular meetings to discuss and reinforce the use of sanitary facilities (incorporate into regular safety meetings).
 Establish a continuing education program to indoctrinate new employees.

Costs
All of the above are low cost measures.

Sanitary/Septic Waste Management WM-9
August 2023 CASQA Stormwater BMP Handbook 3 of 3
Construction www.casqa.org
Inspection and Maintenance
 BMPs must be inspected in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 Arrange for regular waste collection.
 If high winds are expected, portable sanitary facilities must be secured with spikes or weighed down to prevent over turning.
 If spills or leaks from sanitary or septic facilities occur that are not contained and discharge from the site, non-visible sampling of site discharge may be required. Refer to the General Permit or to your project specific Construction Site Monitoring Plan to determine if and where sampling is required.

References
Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), March 2003.

Stormwater Management for Construction Activities; Developing Pollution Prevention Plans and Best Management Practice, EPA 832-R-92005; USEPA, April 1992.

CASQA Traditional SWPPP Template H-1 August 2023
for the 2022 CGP
Appendix H: BMP Inspection Form

CASQA Traditional SWPPP Template H-2 August 2023
for the 2022 CGP

BMP INSPECTION REPORT

Date and Time of Inspection: Date Report Written:

Inspection Type:
(Circle one)
Weekly
Complete
Parts I,II,III
and VII
Pre-Qualifying
Precipitation
Event (QPE)
Complete Parts
I,II,III,IV and VII
During QPE
Complete Parts
I, II, III, V, and
VII
Post-QPE
Complete Parts
I,II,III,VI and VII
Inactive
Project
Complete
Parts I,II,III
and VII
Part I. General Information
Site Information
Construction Site Name:

Construction stage and
completed activities:

Approximate area
of site that is exposed:

Photos Taken:
(Circle one) Yes No
Photo Reference IDs:

Weather
Estimate storm beginning:
(date and time)
Estimate storm duration:
(hours)
Estimate time since last storm:
(days or hours)
Rain gauge reading and location:
(in)
Is a “Qualifying Precipitation Event” predicted or did one occur (i.e., any weather pattern with a 50% chance of

0.5” or more within a 24-hr period when 0.5” has been forecast and continues on subsequent 24-hour periods when 0.25” of precipitation or more is forecast)? (Y/N) If yes, summarize forecast:

Exception Documentation (explanation required if inspection could not be conducted). Visual inspections are not required outside of business hours or during dangerous weather conditions such as electrical storms, flooding, and high winds above 40 miles per hour.

Inspector Information
Inspector Name: Inspector Title:

Inspector Certification: Date:

CASQA Traditional SWPPP Template H-3 August 2023
for the 2022 CGP
Part II. BMP Observations. Describe deficiencies in Part III.

Minimum BMPs for Risk Level _____ Sites
Adequately
designed,
implemented
and effective
(yes, no, N/A)
Action
Required
(yes/no)
Action Implemented
(Date)
Good Housekeeping for Construction Materials
Inventory of products (excluding materials designed to be outdoors)
Stockpiled construction materials not actively in use are covered and bermed
All chemicals are stored in watertight containers with
appropriate secondary containment, or in a completely
enclosed storage shed

Construction materials are minimally exposed to precipitation BMPs preventing the off-site tracking of materials are
implemented and properly effective
Good Housekeeping for Waste Management
Wash/rinse water and materials are prevented from being disposed into the storm drain system
Portable toilets are contained to prevent discharges of waste Sanitation facilities are clean and with no apparent for leaks and spills
Equipment is in place to cover waste disposal containers at the end of business day and during rain events
Discharges from waste disposal containers are prevented from discharging to the storm drain system / receiving water Stockpiled waste material is securely protected from wind and rain if not actively in use
Procedures are in place for addressing hazardous and non- hazardous spills
Appropriate spill response personnel are assigned and trained Equipment and materials for cleanup of spills is available onsite
Washout areas (e.g., concrete) are contained appropriately to prevent discharge or infiltration into the underlying soil Good Housekeeping for Vehicle Storage and Maintenance
Measures are in place to prevent oil, grease, or fuel from leaking into the ground, storm drains, or surface waters All equipment or vehicles are fueled, maintained, and stored in a designated area with appropriate BMPs
Vehicle and equipment leaks are cleaned immediately and disposed of properly

CASQA Traditional SWPPP Template H-4 August 2023
for the 2022 CGP
Part II. BMP Observations Continued. Describe deficiencies in Part III.

Minimum BMPs for Risk Level _____ Sites
Adequately
designed,
implemented and
effective
(yes, no, N/A)
Action
Required
(yes/no)
Action Implemented
(Date)
Good Housekeeping for Landscape Materials
Stockpiled landscape materials such as mulches and topsoil are contained and covered when not actively in use
Erodible landscape material has not been applied 2 days before a forecasted rain event or during an event
Erodible landscape materials are applied at quantities and rates in accordance with manufacturer recommendations
Bagged erodible landscape materials are stored on pallets and covered
Good Housekeeping for Air Deposition of Site Materials
Good housekeeping measures are implemented onsite to
control the air deposition of site materials and from site operations

Non-Stormwater Management
Non-Stormwater discharges are properly controlled
Vehicles are washed in a manner to prevent non-stormwater discharges to surface waters or drainage systems
Streets are cleaned in a manner to prevent unauthorized non- stormwater discharges to surface waters or drainage systems.

Erosion Controls
Wind erosion controls are effectively implemented

Effective soil cover is provided for disturbed areas inactive (i.e., not scheduled to be disturbed for 14 days) as well as finished slopes, open space, utility backfill, and completed lots

The use of plastic materials is limited in cases when a more sustainable, environmentally friendly alternative exists.

Sediment Controls
Perimeter controls are established and effective at controlling erosion and sediment discharges from the site
Entrances and exits are stabilized to control erosion and sediment discharges from the site
Sediment basins are properly maintained
Inspect immediate access roads prior to forecasted
precipitation
Linear sediment control along toe of slope, face of slope an at grade breaks (Risk Level 2 & 3 Only)
Limit construction activity to and from site to entrances and exits that employ effective controls to prevent offsite tracking (Risk Level 2 & 3 Only)

Ensure all storm, drain inlets and perimeter controls, runoff control BMPs and pollutants controls at entrances and exits

CASQA Traditional SWPPP Template H-5 August 2023
for the 2022 CGP
are maintained and protected from activities the reduce their effectiveness (Risk Level 2 & 3 Only)
Run-On and Run-Off Controls
Run-on to the site is effectively managed and directed away from all disturbed areas.

Other
Are the project SWPPP and BMP plan up to date, available onsite and being properly implemented?
Is the posting of the project’s unique WDID number, waiver identification number, and site and project contact information publicly accessible?

Part III. Descriptions of BMP Deficiencies
Deficiency
Repairs Implemented:

Note - Repairs must begin within 72 hours of identification and, complete repairs as soon as possible.

Start Date Action

1. 2.

3. 4.

Part IV. Additional Pre-QPE Observations. Note the presence or absence of floating and suspended materials, sheen, discoloration, turbidity, odors, and source(s) of pollutants(s).

Yes, No, N/A
Do stormwater storage and containment areas have adequate freeboard? If no, complete Part III.

Are drainage areas free of spills, leaks, or uncontrolled pollutant sources? If no, complete Part VII and describe below.

Notes:

Are stormwater storage and containment areas free of leaks? If no, complete Parts III and/or VII and describe below.

Notes:

CASQA Traditional SWPPP Template H-6 August 2023
for the 2022 CGP
Part V. Additional During-QPE Observations. If BMPs cannot be inspected during inclement weather, list the results of visual inspections at all relevant outfalls, discharge points, and downstream locations. Note odors or visible sheen on the surface of discharges. Complete Part VII (Corrective Actions) as needed.

Outfall, Discharge Point, or Other Downstream Location
Location Description
Location Description
Location Description
Location Description

Part VI. Additional Post-QPE Observations. Visually observe (inspect) stormwater discharges at all discharge locations within 96 hours after each qualifying precipitation event, and observe (inspect) the discharge of stored or contained stormwater that is derived from and discharged subsequent to a qualifying precipitation event producing precipitation of ½ inch or more at the time of discharge. Complete Part VII (Corrective Actions) as needed.

Discharge Location, Storage or
Containment Area
Visual Observation

Part VII. Additional Corrective Actions Required. Identify additional corrective actions not included with BMP Deficiencies (Part III) above. Note if SWPPP change is required.

Required Actions Implementation Date

CASQA Traditional SWPPP Template I-1 August 2023
for the 2022 CGP
Appendix I: Training Forms

CASQA Traditional SWPPP Template I-2 August 2023
for the 2022 CGP
Contractor Personnel Training Log
Stormwater Management Training Log and Documentation

Project Name:

WDID #:

Stormwater Management Topic: (check as appropriate)
☐ Good Housekeeping BMPs ☐ Erosion Control BMPs
☐ Sediment Control BMPs ☐ Tracking Control
☐ Non-Stormwater Management BMPs ☐ Waste Management & Pollution Control BMPs ☐ BMP Implementation Activities ☐ Advanced BMPs
☐ Identification of QSPs and QSP Delegates

Training Objective:

Date: _ Instructor:

Training Length (hours):

Attendee Roster (Attach additional forms if necessary)
Name Company Phone

CASQA Traditional SWPPP Template I-3 August 2023
for the 2022 CGP
QSP Delegate Training Log
Stormwater Management Training Log and Documentation

Project Name:

WDID #:

QSP Delegate Name:

Delegated Responsibilities:
☐ Stormwater Visual Inspections
☐ Sampling
☐ BMP Inspections
☐ BMP Maintenance and Repair

Foundational Training
Topic Date Completed QSP Trainer
☐ Roles and Responsibilities
☐ Forecast Information
☐ Documentation and Reporting Procedures

Site-Specific Training
Topic Date Completed QSP Trainer
☐ Visual Inspections
☐ Sample Collection Procedures
☐ Sample Reporting Procedures
☐ BMP Implementation

As needed, attach proof of external training (e.g., course completion certificates, credentials for the QSP Delegate).

CASQA Traditional SWPPP Template J-1 August 2023
for the 2022 CGP
Appendix J: Responsible Parties

CASQA Traditional SWPPP Template J-2 August 2023
for the 2022 CGP
Identification of QSP and QSP Delegates
Project Name:

WDID #:

The following are QSPs and QSP Delegates associated with this project

Name of Personnel(1) QSP Number, or
state “Delegate”
Company Date

(1) If additional QSPs or QSP Delegates are required on the job site add additional lines

CASQA Traditional SWPPP Template K-1 August 2023
for the 2022 CGP
Appendix K: Contractors and Subcontractors

Contractor Name:

Title:

Contractor Company:

Address
Phone Number:

Phone Number (24/7)
[Add additional rows, if
needed]

CASQA Traditional SWPPP Template L-1 August 2023
for the 2022 CGP
Appendix L: Calculations

…VMP - Hydrology & Hydraulic Report - Final.docx page 8

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
Existing 2-Year Storm Event Hydrology
____________________________________________________________________________ ****************************************************************************

RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE
Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT
2003,1985,1981 HYDROLOGY MANUAL
(c) Copyright 1982-2015 Advanced Engineering Software (aes) Ver. 22.0 Release Date: 07/01/2015 License ID 1678

Analysis prepared by:

civTEC
999 Corporate Dr., Suite 100
Ladera Ranch, CA 92694
ph: 949.463.8822

************************** DESCRIPTION OF STUDY ************************** * VETERANS MEMORIAL PARK * * EXISTING CONDITION * * 2-YEAR STORM EVENT * **************************************************************************

FILE NAME: VMP_E2YR.DAT
TIME/DATE OF STUDY: 16:24 01/22/2023
---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION:
---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA

USER SPECIFIED STORM EVENT(YEAR) = 2.00
6-HOUR DURATION PRECIPITATION (INCHES) = 1.200
SPECIFIED MINIMUM PIPE SIZE(INCH) = 12.00
SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING

WIDTH CROSSFALL IN- / OUT-/PARK- HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) === ===== ========= ================= ====== ===== ====== ===== ======= 1 26.0 12.0 0.020/0.020/0.020 0.50 1.50 0.0313 0.167 0.0150

GLOBAL STREET FLOW-DEPTH CONSTRAINTS:

1. Relative Flow-Depth = 1.00 FEET
as (Maximum Allowable Street Flow Depth) - (Top-of-Curb)

2. (Depth)*(Velocity) Constraint = 10.0 (FT*FT/S)
*SIZE PIPE WITH A FLOW CAPACITY GREATER THAN
OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.*

**************************************************************************** FLOW PROCESS FROM NODE 1.10 TO NODE 1.15 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<<
============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 108.00
DOWNSTREAM ELEVATION(FEET) = 93.00
ELEVATION DIFFERENCE(FEET) = 15.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.733
SUBAREA RUNOFF(CFS) = 0.11
TOTAL AREA(ACRES) = 0.12 TOTAL RUNOFF(CFS) = 0.11

…VMP - Hydrology & Hydraulic Report - Final.docx page 9

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS

**************************************************************************** FLOW PROCESS FROM NODE 1.15 TO NODE 1.20 IS CODE = 52 ---------------------------------------------------------------------------- >>>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 268.00
DOWNSTREAM ELEVATION(FEET) = 258.00
ELEVATION DIFFERENCE(FEET) = 10.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.733
SUBAREA RUNOFF(CFS) = 0.11
TOTAL AREA(ACRES) = 0.11 TOTAL RUNOFF(CFS) = 0.11

…VMP - Hydrology & Hydraulic Report - Final.docx page 10

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS

**************************************************************************** FLOW PROCESS FROM NODE 3.15 TO NODE 3.20 IS CODE = 52 ---------------------------------------------------------------------------- >>>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================

…VMP - Hydrology & Hydraulic Report - Final.docx page 11

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.442
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 0.90 SUBAREA RUNOFF(CFS) = 0.77 TOTAL AREA(ACRES) = 1.0 TOTAL RUNOFF(CFS) = 0.86 TC(MIN.) = 7.46

**************************************************************************** FLOW PROCESS FROM NODE 5.10 TO NODE 5.15 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ LIMITED INDUSTRIAL RUNOFF COEFFICIENT = .8500
SOIL CLASSIFICATION IS "D"

…VMP - Hydrology & Hydraulic Report - Final.docx page 12

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
S.C.S. CURVE NUMBER (AMC II) = 96
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 126.90
DOWNSTREAM ELEVATION(FEET) = 126.10
ELEVATION DIFFERENCE(FEET) = 0.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 3.627
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 56.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.162
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.27
TOTAL AREA(ACRES) = 0.10 TOTAL RUNOFF(CFS) = 0.27

**************************************************************************** FLOW PROCESS FROM NODE 5.35 TO NODE 5.40 IS CODE = 62 ---------------------------------------------------------------------------- >>>>>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA >>>>(STREET TABLE SECTION # 1 USED) >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 86.00 DOWNSTREAM(FEET) = 84.00 FLOW LENGTH(FEET) = 82.00 MANNING'S N = 0.013
DEPTH OF FLOW IN 24.0 INCH PIPE IS 7.6 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 8.80
GIVEN PIPE DIAMETER(INCH) = 24.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 7.58
PIPE TRAVEL TIME(MIN.) = 0.16 Tc(MIN.) = 10.12

…VMP - Hydrology & Hydraulic Report - Final.docx page 13

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
LONGEST FLOWPATH FROM NODE 5.30 TO NODE 5.50 = 1507.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 14

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
============================================================================ 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.480
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 1.25 SUBAREA RUNOFF(CFS) = 1.09 TOTAL AREA(ACRES) = 1.4 TOTAL RUNOFF(CFS) = 1.19 TC(MIN.) = 7.29

**************************************************************************** FLOW PROCESS FROM NODE 7.10 TO NODE 7.15 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 1.951
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 7.02 SUBAREA RUNOFF(CFS) = 4.79 TOTAL AREA(ACRES) = 7.2 TOTAL RUNOFF(CFS) = 4.90 TC(MIN.) = 10.57
============================================================================ ============================================================================

END OF RATIONAL METHOD ANALYSIS

…VMP - Hydrology & Hydraulic Report - Final.docx page 15

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
Proposed 2-Year Storm Event Hydrology
____________________________________________________________________________ ****************************************************************************

Analysis prepared by:

civTEC
999 Corporate Dr., Suite 100
Ladera Ranch, CA 92694
ph: 949.463.8822

************************** DESCRIPTION OF STUDY ************************** * VETERANS MEMORIAL PARK * * PROPOSED CONDITION * * 2-YEAR STORM EVENT * **************************************************************************

FILE NAME: VMP_P2.DAT
TIME/DATE OF STUDY: 09:31 07/04/2024
---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION:
---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA

USER SPECIFIED STORM EVENT(YEAR) = 2.00
6-HOUR DURATION PRECIPITATION (INCHES) = 1.200
SPECIFIED MINIMUM PIPE SIZE(INCH) = 4.00
SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING

WIDTH CROSSFALL IN- / OUT-/PARK- HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) === ===== ========= ================= ====== ===== ====== ===== ======= 1 26.0 10.0 0.020/0.020/0.020 0.50 1.50 0.0312 0.167 0.0150

GLOBAL STREET FLOW-DEPTH CONSTRAINTS:

1. Relative Flow-Depth = 0.00 FEET
as (Maximum Allowable Street Flow Depth) - (Top-of-Curb)

2. (Depth)*(Velocity) Constraint = 6.0 (FT*FT/S)
*SIZE PIPE WITH A FLOW CAPACITY GREATER THAN
OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.*

**************************************************************************** FLOW PROCESS FROM NODE 1.01 TO NODE 1.02 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<<
============================================================================ LAWNS, GOLF COURSES, ETC. GOOD COVER RUNOFF COEFFICIENT = .3500 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 80
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 91.80
DOWNSTREAM ELEVATION(FEET) = 82.00
ELEVATION DIFFERENCE(FEET) = 9.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.309
2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.721
SUBAREA RUNOFF(CFS) = 0.14
TOTAL AREA(ACRES) = 0.15 TOTAL RUNOFF(CFS) = 0.14

…VMP - Hydrology & Hydraulic Report - Final.docx page 16

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
**************************************************************************** FLOW PROCESS FROM NODE 1.02 TO NODE 1.03 IS CODE = 51 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ STREETS & ROADS (CURBS/STORM DRAINS) RUNOFF COEFFICIENT = .8700 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 98
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 68.30
DOWNSTREAM ELEVATION(FEET) = 65.70

…VMP - Hydrology & Hydraulic Report - Final.docx page 17

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
ELEVATION DIFFERENCE(FEET) = 2.60
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 2.625
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 76.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.162
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.14
TOTAL AREA(ACRES) = 0.05 TOTAL RUNOFF(CFS) = 0.14

**************************************************************************** FLOW PROCESS FROM NODE 2.02 TO NODE 2.03 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 51.75 DOWNSTREAM(FEET) = 49.30 FLOW LENGTH(FEET) = 60.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 9.0 INCH PIPE IS 4.2 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 8.44

…VMP - Hydrology & Hydraulic Report - Final.docx page 18

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
ESTIMATED PIPE DIAMETER(INCH) = 9.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 1.71
PIPE TRAVEL TIME(MIN.) = 0.12 Tc(MIN.) = 2.96
LONGEST FLOWPATH FROM NODE 2.01 TO NODE 2.20 = 240.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 3.01 TO NODE 3.02 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 82.50 DOWNSTREAM(FEET) = 45.50 FLOW LENGTH(FEET) = 715.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 15.0 INCH PIPE IS 8.8 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 14.66
ESTIMATED PIPE DIAMETER(INCH) = 15.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 10.90
PIPE TRAVEL TIME(MIN.) = 0.81 Tc(MIN.) = 13.66
LONGEST FLOWPATH FROM NODE 3.01 TO NODE 3.20 = 2630.00 FEET.

****************************************************************************

…VMP - Hydrology & Hydraulic Report - Final.docx page 19

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
FLOW PROCESS FROM NODE 3.20 TO NODE 3.20 IS CODE = 10 ---------------------------------------------------------------------------- >>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 187.00 DOWNSTREAM(FEET) = 54.80 FLOW LENGTH(FEET) = 1085.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 6.0 INCH PIPE IS 2.0 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 9.32
ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.52
PIPE TRAVEL TIME(MIN.) = 1.94 Tc(MIN.) = 8.70
LONGEST FLOWPATH FROM NODE 3.04 TO NODE 3.07 = 1360.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 3.07 TO NODE 3.07 IS CODE = 81 ----------------------------------------------------------------------------

…VMP - Hydrology & Hydraulic Report - Final.docx page 20

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
>>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"

…VMP - Hydrology & Hydraulic Report - Final.docx page 21

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 204.00
DOWNSTREAM ELEVATION(FEET) = 178.00
ELEVATION DIFFERENCE(FEET) = 26.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.733
SUBAREA RUNOFF(CFS) = 0.11
TOTAL AREA(ACRES) = 0.11 TOTAL RUNOFF(CFS) = 0.11

**************************************************************************** FLOW PROCESS FROM NODE 4.02 TO NODE 4.03 IS CODE = 52 ---------------------------------------------------------------------------- >>>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 270.00
DOWNSTREAM ELEVATION(FEET) = 266.00
ELEVATION DIFFERENCE(FEET) = 4.00

…VMP - Hydrology & Hydraulic Report - Final.docx page 22

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.505
2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.244
SUBAREA RUNOFF(CFS) = 0.42
TOTAL AREA(ACRES) = 0.54 TOTAL RUNOFF(CFS) = 0.42

**************************************************************************** FLOW PROCESS FROM NODE 5.02 TO NODE 5.03 IS CODE = 52 ---------------------------------------------------------------------------- >>>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 270.00
DOWNSTREAM ELEVATION(FEET) = 266.00
ELEVATION DIFFERENCE(FEET) = 4.00

…VMP - Hydrology & Hydraulic Report - Final.docx page 23

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.505
2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.244
SUBAREA RUNOFF(CFS) = 0.24
TOTAL AREA(ACRES) = 0.30 TOTAL RUNOFF(CFS) = 0.24

**************************************************************************** FLOW PROCESS FROM NODE 5.06 TO NODE 5.07 IS CODE = 52 ---------------------------------------------------------------------------- >>>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY<<<<< ============================================================================

** MAIN STREAM CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 7.58 13.27 1.685 12.75
LONGEST FLOWPATH FROM NODE 5.05 TO NODE 5.04 = 1560.00 FEET.

** MEMORY BANK # 1 CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 10.21 13.69 1.651 17.51
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.04 = 1625.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 24

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
** PEAK FLOW RATE TABLE **
STREAM RUNOFF Tc INTENSITY
NUMBER (CFS) (MIN.) (INCH/HOUR)
1 17.47 13.27 1.685
2 17.64 13.69 1.651

COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS:

PEAK FLOW RATE(CFS) = 17.64 Tc(MIN.) = 13.69
TOTAL AREA(ACRES) = 30.3

**************************************************************************** FLOW PROCESS FROM NODE 5.04 TO NODE 5.04 IS CODE = 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 218.00 DOWNSTREAM(FEET) = 103.50 CHANNEL LENGTH THRU SUBAREA(FEET) = 780.00 CHANNEL SLOPE = 0.1468 NOTE: CHANNEL FLOW OF 1. CFS WAS ASSUMED IN VELOCITY ESTIMATION NOTE: CHANNEL SLOPE OF .1 WAS ASSUMED IN VELOCITY ESTIMATION CHANNEL FLOW THRU SUBAREA(CFS) = 0.15
FLOW VELOCITY(FEET/SEC) = 4.74 (PER LACFCD/RCFC&WCD HYDROLOGY MANUAL)

…VMP - Hydrology & Hydraulic Report - Final.docx page 25

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
TRAVEL TIME(MIN.) = 2.74 Tc(MIN.) = 9.01
LONGEST FLOWPATH FROM NODE 5.09 TO NODE 5.11 = 880.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.11 TO NODE 5.11 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 2 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 153.00 DOWNSTREAM(FEET) = 108.50 CHANNEL LENGTH THRU SUBAREA(FEET) = 235.00 CHANNEL SLOPE = 0.1894 NOTE: CHANNEL FLOW OF 1. CFS WAS ASSUMED IN VELOCITY ESTIMATION NOTE: CHANNEL SLOPE OF .1 WAS ASSUMED IN VELOCITY ESTIMATION CHANNEL FLOW THRU SUBAREA(CFS) = 0.11

…VMP - Hydrology & Hydraulic Report - Final.docx page 26

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
FLOW VELOCITY(FEET/SEC) = 4.74 (PER LACFCD/RCFC&WCD HYDROLOGY MANUAL) TRAVEL TIME(MIN.) = 0.83 Tc(MIN.) = 7.09
LONGEST FLOWPATH FROM NODE 5.13 TO NODE 5.15 = 335.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.15 TO NODE 5.15 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>CONFLUENCE MEMORY BANK # 2 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 2 <<<<< ============================================================================

…VMP - Hydrology & Hydraulic Report - Final.docx page 27

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
**************************************************************************** FLOW PROCESS FROM NODE 5.12 TO NODE 5.08 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 90.00 DOWNSTREAM(FEET) = 72.60 FLOW LENGTH(FEET) = 150.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 15.0 INCH PIPE IS 11.1 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 23.35
ESTIMATED PIPE DIAMETER(INCH) = 15.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 22.65
PIPE TRAVEL TIME(MIN.) = 0.11 Tc(MIN.) = 14.40
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.20 = 2265.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 10 ----------------------------------------------------------------------------

…VMP - Hydrology & Hydraulic Report - Final.docx page 28

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
>>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 78.80 DOWNSTREAM(FEET) = 72.60 FLOW LENGTH(FEET) = 90.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 15.0 INCH PIPE IS 8.0 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 16.34
ESTIMATED PIPE DIAMETER(INCH) = 15.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 10.85
PIPE TRAVEL TIME(MIN.) = 0.09 Tc(MIN.) = 8.01

…VMP - Hydrology & Hydraulic Report - Final.docx page 29

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
LONGEST FLOWPATH FROM NODE 5.16 TO NODE 5.20 = 810.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ GENERAL COMMERCIAL RUNOFF COEFFICIENT = .8200
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 95
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 126.90
DOWNSTREAM ELEVATION(FEET) = 126.10
ELEVATION DIFFERENCE(FEET) = 0.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 4.063
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 56.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.162
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.26
TOTAL AREA(ACRES) = 0.10 TOTAL RUNOFF(CFS) = 0.26

**************************************************************************** FLOW PROCESS FROM NODE 5.32 TO NODE 5.33 IS CODE = 61 ----------------------------------------------------------------------------

…VMP - Hydrology & Hydraulic Report - Final.docx page 30

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
>>>>>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA >>>>(STANDARD CURB SECTION USED) >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY<<<<< ============================================================================

** MAIN STREAM CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 5.92 10.86 1.917 3.75
LONGEST FLOWPATH FROM NODE 5.31 TO NODE 5.20 = 1510.00 FEET.

** MEMORY BANK # 1 CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 30.08 14.40 1.598 50.01

…VMP - Hydrology & Hydraulic Report - Final.docx page 31

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.20 = 2265.00 FEET.

** PEAK FLOW RATE TABLE **
STREAM RUNOFF Tc INTENSITY
NUMBER (CFS) (MIN.) (INCH/HOUR)
1 28.60 10.86 1.917
2 35.02 14.40 1.598

COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS:

PEAK FLOW RATE(CFS) = 35.02 Tc(MIN.) = 14.40
TOTAL AREA(ACRES) = 53.8

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.390
RESIDENTIAL (1. DU/AC OR LESS) RUNOFF COEFFICIENT = .4100 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 82
AREA-AVERAGE RUNOFF COEFFICIENT = 0.4026
SUBAREA AREA(ACRES) = 1.20 SUBAREA RUNOFF(CFS) = 1.18 TOTAL AREA(ACRES) = 1.4 TOTAL RUNOFF(CFS) = 1.32

…VMP - Hydrology & Hydraulic Report - Final.docx page 32

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
TC(MIN.) = 7.72

**************************************************************************** FLOW PROCESS FROM NODE 6.03 TO NODE 6.20 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 2 YEAR RAINFALL INTENSITY(INCH/HOUR) = 1.951
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 7.02 SUBAREA RUNOFF(CFS) = 4.79 TOTAL AREA(ACRES) = 7.2 TOTAL RUNOFF(CFS) = 4.90 TC(MIN.) = 10.57
============================================================================ ============================================================================

END OF RATIONAL METHOD ANALYSIS

…VMP - Hydrology & Hydraulic Report - Final.docx page 33

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
Existing 25-Year Storm Event Hydrology

____________________________________________________________________________ ****************************************************************************

Analysis prepared by:

civTEC
999 Corporate Dr., Suite 100
Ladera Ranch, CA 92694
ph: 949.463.8822

************************** DESCRIPTION OF STUDY ************************** * VETERANS MEMORIAL PARK * * EXISTING CONDITION * * 25-YEAR STORM EVENT * **************************************************************************

FILE NAME: VMP_E25.DAT
TIME/DATE OF STUDY: 16:34 01/22/2023
---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION:
---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA

USER SPECIFIED STORM EVENT(YEAR) = 25.00
6-HOUR DURATION PRECIPITATION (INCHES) = 2.100
SPECIFIED MINIMUM PIPE SIZE(INCH) = 12.00
SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING

GLOBAL STREET FLOW-DEPTH CONSTRAINTS:

1. Relative Flow-Depth = 1.00 FEET
as (Maximum Allowable Street Flow Depth) - (Top-of-Curb)

2. (Depth)*(Velocity) Constraint = 10.0 (FT*FT/S)
*SIZE PIPE WITH A FLOW CAPACITY GREATER THAN
OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.*

**************************************************************************** FLOW PROCESS FROM NODE 1.10 TO NODE 1.15 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<<
============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 108.00
DOWNSTREAM ELEVATION(FEET) = 93.00
ELEVATION DIFFERENCE(FEET) = 15.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.783
SUBAREA RUNOFF(CFS) = 0.20

…VMP - Hydrology & Hydraulic Report - Final.docx page 34

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
TOTAL AREA(ACRES) = 0.12 TOTAL RUNOFF(CFS) = 0.20

**************************************************************************** FLOW PROCESS FROM NODE 1.15 TO NODE 1.20 IS CODE = 52 ---------------------------------------------------------------------------- >>>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 268.00
DOWNSTREAM ELEVATION(FEET) = 258.00
ELEVATION DIFFERENCE(FEET) = 10.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.783
SUBAREA RUNOFF(CFS) = 0.18

…VMP - Hydrology & Hydraulic Report - Final.docx page 35

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
TOTAL AREA(ACRES) = 0.11 TOTAL RUNOFF(CFS) = 0.18

…VMP - Hydrology & Hydraulic Report - Final.docx page 36

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
============================================================================ 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.274
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 0.90 SUBAREA RUNOFF(CFS) = 1.35 TOTAL AREA(ACRES) = 1.0 TOTAL RUNOFF(CFS) = 1.51 TC(MIN.) = 7.46

…VMP - Hydrology & Hydraulic Report - Final.docx page 37

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 96
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 126.90
DOWNSTREAM ELEVATION(FEET) = 126.10
ELEVATION DIFFERENCE(FEET) = 0.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 3.627
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 56.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.533
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.47
TOTAL AREA(ACRES) = 0.10 TOTAL RUNOFF(CFS) = 0.47

…VMP - Hydrology & Hydraulic Report - Final.docx page 38

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
PIPE-FLOW VELOCITY(FEET/SEC.) = 10.40
GIVEN PIPE DIAMETER(INCH) = 24.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 14.03
PIPE TRAVEL TIME(MIN.) = 0.13 Tc(MIN.) = 9.27
LONGEST FLOWPATH FROM NODE 5.30 TO NODE 5.50 = 1507.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.50 TO NODE 5.40 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 148.00 DOWNSTREAM(FEET) = 108.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 290.00 CHANNEL SLOPE = 0.1379 NOTE: CHANNEL FLOW OF 1. CFS WAS ASSUMED IN VELOCITY ESTIMATION NOTE: CHANNEL SLOPE OF .1 WAS ASSUMED IN VELOCITY ESTIMATION CHANNEL FLOW THRU SUBAREA(CFS) = 0.20
FLOW VELOCITY(FEET/SEC) = 4.74 (PER LACFCD/RCFC&WCD HYDROLOGY MANUAL) TRAVEL TIME(MIN.) = 1.02 Tc(MIN.) = 7.29
LONGEST FLOWPATH FROM NODE 6.10 TO NODE 6.20 = 390.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 39

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
**************************************************************************** FLOW PROCESS FROM NODE 6.20 TO NODE 6.20 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.414
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 7.02 SUBAREA RUNOFF(CFS) = 8.39 TOTAL AREA(ACRES) = 7.2 TOTAL RUNOFF(CFS) = 8.57 TC(MIN.) = 10.57
============================================================================ ============================================================================

END OF RATIONAL METHOD ANALYSIS

…VMP - Hydrology & Hydraulic Report - Final.docx page 40

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
Proposed 25-Year Storm Event Hydrology
____________________________________________________________________________ ****************************************************************************

Analysis prepared by:

civTEC
999 Corporate Dr., Suite 100
Ladera Ranch, CA 92694
ph: 949.463.8822

************************** DESCRIPTION OF STUDY ************************** * VETERANS MEMORIAL PARK * * PROPOSED CONDITION * * 25-YEAR STORM EVENT * **************************************************************************

FILE NAME: VMP_P25.DAT
TIME/DATE OF STUDY: 09:43 07/04/2024
---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION:
---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA

USER SPECIFIED STORM EVENT(YEAR) = 25.00
6-HOUR DURATION PRECIPITATION (INCHES) = 2.100
SPECIFIED MINIMUM PIPE SIZE(INCH) = 4.00
SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING

WIDTH CROSSFALL IN- / OUT-/PARK- HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) === ===== ========= ================= ====== ===== ====== ===== ======= 1 26.0 10.0 0.020/0.020/0.020 0.50 1.50 0.0312 0.167 0.0150

GLOBAL STREET FLOW-DEPTH CONSTRAINTS:

1. Relative Flow-Depth = 0.00 FEET
as (Maximum Allowable Street Flow Depth) - (Top-of-Curb)

2. (Depth)*(Velocity) Constraint = 6.0 (FT*FT/S)
*SIZE PIPE WITH A FLOW CAPACITY GREATER THAN
OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.*

**************************************************************************** FLOW PROCESS FROM NODE 1.01 TO NODE 1.02 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<<
============================================================================ LAWNS, GOLF COURSES, ETC. GOOD COVER RUNOFF COEFFICIENT = .3500 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 80
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 91.80
DOWNSTREAM ELEVATION(FEET) = 82.00
ELEVATION DIFFERENCE(FEET) = 9.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.309
25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.762
SUBAREA RUNOFF(CFS) = 0.25
TOTAL AREA(ACRES) = 0.15 TOTAL RUNOFF(CFS) = 0.25

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…VMP - Hydrology & Hydraulic Report - Final.docx page 42

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
ELEVATION DIFFERENCE(FEET) = 2.60
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 2.625
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 76.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.533
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.24
TOTAL AREA(ACRES) = 0.05 TOTAL RUNOFF(CFS) = 0.24

…VMP - Hydrology & Hydraulic Report - Final.docx page 43

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
ESTIMATED PIPE DIAMETER(INCH) = 9.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 2.99
PIPE TRAVEL TIME(MIN.) = 0.10 Tc(MIN.) = 2.91
LONGEST FLOWPATH FROM NODE 2.01 TO NODE 2.20 = 240.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 3.01 TO NODE 3.02 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 82.50 DOWNSTREAM(FEET) = 45.50 FLOW LENGTH(FEET) = 715.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 18.0 INCH PIPE IS 11.0 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 16.82
ESTIMATED PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 19.08
PIPE TRAVEL TIME(MIN.) = 0.71 Tc(MIN.) = 13.55
LONGEST FLOWPATH FROM NODE 3.01 TO NODE 3.20 = 2630.00 FEET.

****************************************************************************

…VMP - Hydrology & Hydraulic Report - Final.docx page 44

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
FLOW PROCESS FROM NODE 3.20 TO NODE 3.20 IS CODE = 10 ---------------------------------------------------------------------------- >>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 187.00 DOWNSTREAM(FEET) = 54.80 FLOW LENGTH(FEET) = 1085.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 6.0 INCH PIPE IS 2.7 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 10.85
ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.92
PIPE TRAVEL TIME(MIN.) = 1.67 Tc(MIN.) = 8.35
LONGEST FLOWPATH FROM NODE 3.04 TO NODE 3.07 = 1360.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 45

…VMP - Hydrology & Hydraulic Report - Final.docx page 46

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 204.00
DOWNSTREAM ELEVATION(FEET) = 178.00
ELEVATION DIFFERENCE(FEET) = 26.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.783
SUBAREA RUNOFF(CFS) = 0.18
TOTAL AREA(ACRES) = 0.11 TOTAL RUNOFF(CFS) = 0.18

…VMP - Hydrology & Hydraulic Report - Final.docx page 47

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.505
25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.928
SUBAREA RUNOFF(CFS) = 0.74
TOTAL AREA(ACRES) = 0.54 TOTAL RUNOFF(CFS) = 0.74

…VMP - Hydrology & Hydraulic Report - Final.docx page 48

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.505
25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.928
SUBAREA RUNOFF(CFS) = 0.41
TOTAL AREA(ACRES) = 0.30 TOTAL RUNOFF(CFS) = 0.41

** MAIN STREAM CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 13.26 13.25 2.952 12.75
LONGEST FLOWPATH FROM NODE 5.05 TO NODE 5.04 = 1560.00 FEET.

** MEMORY BANK # 1 CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 17.87 13.67 2.893 17.51
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.04 = 1625.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 49

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
** PEAK FLOW RATE TABLE **
STREAM RUNOFF Tc INTENSITY
NUMBER (CFS) (MIN.) (INCH/HOUR)
1 30.58 13.25 2.952
2 30.87 13.67 2.893

COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS:

PEAK FLOW RATE(CFS) = 30.87 Tc(MIN.) = 13.67
TOTAL AREA(ACRES) = 30.3

**************************************************************************** FLOW PROCESS FROM NODE 5.04 TO NODE 5.04 IS CODE = 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 218.00 DOWNSTREAM(FEET) = 103.50 CHANNEL LENGTH THRU SUBAREA(FEET) = 780.00 CHANNEL SLOPE = 0.1468 NOTE: CHANNEL FLOW OF 1. CFS WAS ASSUMED IN VELOCITY ESTIMATION NOTE: CHANNEL SLOPE OF .1 WAS ASSUMED IN VELOCITY ESTIMATION CHANNEL FLOW THRU SUBAREA(CFS) = 0.27
FLOW VELOCITY(FEET/SEC) = 4.74 (PER LACFCD/RCFC&WCD HYDROLOGY MANUAL)

…VMP - Hydrology & Hydraulic Report - Final.docx page 50

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
TRAVEL TIME(MIN.) = 2.74 Tc(MIN.) = 9.01
LONGEST FLOWPATH FROM NODE 5.09 TO NODE 5.11 = 880.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 51

…VMP - Hydrology & Hydraulic Report - Final.docx page 52

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
**************************************************************************** FLOW PROCESS FROM NODE 5.12 TO NODE 5.08 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 90.00 DOWNSTREAM(FEET) = 72.60 FLOW LENGTH(FEET) = 150.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 18.0 INCH PIPE IS 14.2 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 26.56
ESTIMATED PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 39.62
PIPE TRAVEL TIME(MIN.) = 0.09 Tc(MIN.) = 14.30
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.20 = 2265.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 53

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
>>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 78.80 DOWNSTREAM(FEET) = 72.60 FLOW LENGTH(FEET) = 90.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 15.0 INCH PIPE IS 12.2 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 18.14
ESTIMATED PIPE DIAMETER(INCH) = 15.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 19.40
PIPE TRAVEL TIME(MIN.) = 0.08 Tc(MIN.) = 7.75

…VMP - Hydrology & Hydraulic Report - Final.docx page 54

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
LONGEST FLOWPATH FROM NODE 5.16 TO NODE 5.20 = 810.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ GENERAL COMMERCIAL RUNOFF COEFFICIENT = .8200
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 95
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 126.90
DOWNSTREAM ELEVATION(FEET) = 126.10
ELEVATION DIFFERENCE(FEET) = 0.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 4.063
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 56.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.533
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.45
TOTAL AREA(ACRES) = 0.10 TOTAL RUNOFF(CFS) = 0.45

…VMP - Hydrology & Hydraulic Report - Final.docx page 55

** MAIN STREAM CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 10.96 9.95 3.550 3.75
LONGEST FLOWPATH FROM NODE 5.31 TO NODE 5.20 = 1510.00 FEET.

** MEMORY BANK # 1 CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 52.68 14.30 2.810 50.01

…VMP - Hydrology & Hydraulic Report - Final.docx page 56

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.20 = 2265.00 FEET.

** PEAK FLOW RATE TABLE **
STREAM RUNOFF Tc INTENSITY
NUMBER (CFS) (MIN.) (INCH/HOUR)
1 47.62 9.95 3.550
2 61.35 14.30 2.810

COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS:

PEAK FLOW RATE(CFS) = 61.35 Tc(MIN.) = 14.30
TOTAL AREA(ACRES) = 53.8

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.246
RESIDENTIAL (1. DU/AC OR LESS) RUNOFF COEFFICIENT = .4100 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 82
AREA-AVERAGE RUNOFF COEFFICIENT = 0.4026
SUBAREA AREA(ACRES) = 1.20 SUBAREA RUNOFF(CFS) = 2.09 TOTAL AREA(ACRES) = 1.4 TOTAL RUNOFF(CFS) = 2.34 TC(MIN.) = 7.54

…VMP - Hydrology & Hydraulic Report - Final.docx page 57

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS

**************************************************************************** FLOW PROCESS FROM NODE 6.03 TO NODE 6.20 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 25 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.414
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 7.02 SUBAREA RUNOFF(CFS) = 8.39 TOTAL AREA(ACRES) = 7.2 TOTAL RUNOFF(CFS) = 8.57 TC(MIN.) = 10.57
============================================================================ ============================================================================

END OF RATIONAL METHOD ANALYSIS

…VMP - Hydrology & Hydraulic Report - Final.docx page 58

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
Existing 50-Year Storm Event Hydrology
____________________________________________________________________________ ****************************************************************************

Analysis prepared by:

civTEC
999 Corporate Dr., Suite 100
Ladera Ranch, CA 92694
ph: 949.463.8822

************************** DESCRIPTION OF STUDY ************************** * VETERANS MEMORIAL PARK * * EXISTING CONDITION * * 50-YEAR STORM EVENT * **************************************************************************

FILE NAME: VMP_E50.DAT
TIME/DATE OF STUDY: 16:37 01/22/2023
---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION:
---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA

USER SPECIFIED STORM EVENT(YEAR) = 50.00
6-HOUR DURATION PRECIPITATION (INCHES) = 2.300
SPECIFIED MINIMUM PIPE SIZE(INCH) = 12.00
SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING

GLOBAL STREET FLOW-DEPTH CONSTRAINTS:

1. Relative Flow-Depth = 1.00 FEET
as (Maximum Allowable Street Flow Depth) - (Top-of-Curb)

2. (Depth)*(Velocity) Constraint = 10.0 (FT*FT/S)
*SIZE PIPE WITH A FLOW CAPACITY GREATER THAN
OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.*

**************************************************************************** FLOW PROCESS FROM NODE 1.10 TO NODE 1.15 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<<
============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 108.00
DOWNSTREAM ELEVATION(FEET) = 93.00
ELEVATION DIFFERENCE(FEET) = 15.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.239
SUBAREA RUNOFF(CFS) = 0.22
TOTAL AREA(ACRES) = 0.12 TOTAL RUNOFF(CFS) = 0.22

…VMP - Hydrology & Hydraulic Report - Final.docx page 59

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS

**************************************************************************** FLOW PROCESS FROM NODE 1.15 TO NODE 1.20 IS CODE = 52 ---------------------------------------------------------------------------- >>>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 268.00
DOWNSTREAM ELEVATION(FEET) = 258.00
ELEVATION DIFFERENCE(FEET) = 10.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.239
SUBAREA RUNOFF(CFS) = 0.20
TOTAL AREA(ACRES) = 0.11 TOTAL RUNOFF(CFS) = 0.20

…VMP - Hydrology & Hydraulic Report - Final.docx page 60

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS

…VMP - Hydrology & Hydraulic Report - Final.docx page 61

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.681
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 0.90 SUBAREA RUNOFF(CFS) = 1.47 TOTAL AREA(ACRES) = 1.0 TOTAL RUNOFF(CFS) = 1.65 TC(MIN.) = 7.46

…VMP - Hydrology & Hydraulic Report - Final.docx page 62

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
S.C.S. CURVE NUMBER (AMC II) = 96
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 126.90
DOWNSTREAM ELEVATION(FEET) = 126.10
ELEVATION DIFFERENCE(FEET) = 0.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 3.627
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 56.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.060
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.52
TOTAL AREA(ACRES) = 0.10 TOTAL RUNOFF(CFS) = 0.52

…VMP - Hydrology & Hydraulic Report - Final.docx page 63

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
GIVEN PIPE DIAMETER(INCH) = 24.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 15.47
PIPE TRAVEL TIME(MIN.) = 0.13 Tc(MIN.) = 9.16
LONGEST FLOWPATH FROM NODE 5.30 TO NODE 5.50 = 1507.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.50 TO NODE 5.40 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 148.00 DOWNSTREAM(FEET) = 108.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 290.00 CHANNEL SLOPE = 0.1379 NOTE: CHANNEL FLOW OF 1. CFS WAS ASSUMED IN VELOCITY ESTIMATION NOTE: CHANNEL SLOPE OF .1 WAS ASSUMED IN VELOCITY ESTIMATION CHANNEL FLOW THRU SUBAREA(CFS) = 0.22
FLOW VELOCITY(FEET/SEC) = 4.74 (PER LACFCD/RCFC&WCD HYDROLOGY MANUAL) TRAVEL TIME(MIN.) = 1.02 Tc(MIN.) = 7.29
LONGEST FLOWPATH FROM NODE 6.10 TO NODE 6.20 = 390.00 FEET.

****************************************************************************

…VMP - Hydrology & Hydraulic Report - Final.docx page 64

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
FLOW PROCESS FROM NODE 6.20 TO NODE 6.20 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.739
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 7.02 SUBAREA RUNOFF(CFS) = 9.19 TOTAL AREA(ACRES) = 7.2 TOTAL RUNOFF(CFS) = 9.38 TC(MIN.) = 10.57
============================================================================ ============================================================================

END OF RATIONAL METHOD ANALYSIS

…VMP - Hydrology & Hydraulic Report - Final.docx page 65

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
Proposed 50-Year Storm Event Hydrology
____________________________________________________________________________ ****************************************************************************

Analysis prepared by:

civTEC
999 Corporate Dr., Suite 100
Ladera Ranch, CA 92694
ph: 949.463.8822

************************** DESCRIPTION OF STUDY ************************** * VETERANS MEMORIAL PARK * * PROPOSED CONDITION * * 50-YEAR STORM EVENT * **************************************************************************

FILE NAME: VMP_P50.DAT
TIME/DATE OF STUDY: 09:50 07/04/2024
---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION:
---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA

USER SPECIFIED STORM EVENT(YEAR) = 50.00
6-HOUR DURATION PRECIPITATION (INCHES) = 2.300
SPECIFIED MINIMUM PIPE SIZE(INCH) = 4.00
SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING

WIDTH CROSSFALL IN- / OUT-/PARK- HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) === ===== ========= ================= ====== ===== ====== ===== ======= 1 26.0 10.0 0.020/0.020/0.020 0.50 1.50 0.0312 0.167 0.0150

GLOBAL STREET FLOW-DEPTH CONSTRAINTS:

1. Relative Flow-Depth = 0.00 FEET
as (Maximum Allowable Street Flow Depth) - (Top-of-Curb)

2. (Depth)*(Velocity) Constraint = 6.0 (FT*FT/S)
*SIZE PIPE WITH A FLOW CAPACITY GREATER THAN
OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.*

**************************************************************************** FLOW PROCESS FROM NODE 1.01 TO NODE 1.02 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<<
============================================================================ LAWNS, GOLF COURSES, ETC. GOOD COVER RUNOFF COEFFICIENT = .3500 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 80
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 91.80
DOWNSTREAM ELEVATION(FEET) = 82.00
ELEVATION DIFFERENCE(FEET) = 9.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.309
50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.216
SUBAREA RUNOFF(CFS) = 0.27
TOTAL AREA(ACRES) = 0.15 TOTAL RUNOFF(CFS) = 0.27

…VMP - Hydrology & Hydraulic Report - Final.docx page 66

…VMP - Hydrology & Hydraulic Report - Final.docx page 67

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
ELEVATION DIFFERENCE(FEET) = 2.60
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 2.625
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 76.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.060
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.26
TOTAL AREA(ACRES) = 0.05 TOTAL RUNOFF(CFS) = 0.26

…VMP - Hydrology & Hydraulic Report - Final.docx page 68

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
ESTIMATED PIPE DIAMETER(INCH) = 9.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 3.27
PIPE TRAVEL TIME(MIN.) = 0.10 Tc(MIN.) = 2.90
LONGEST FLOWPATH FROM NODE 2.01 TO NODE 2.20 = 240.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 3.01 TO NODE 3.02 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 82.50 DOWNSTREAM(FEET) = 45.50 FLOW LENGTH(FEET) = 715.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 18.0 INCH PIPE IS 11.7 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 17.14
ESTIMATED PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 20.90
PIPE TRAVEL TIME(MIN.) = 0.70 Tc(MIN.) = 13.54
LONGEST FLOWPATH FROM NODE 3.01 TO NODE 3.20 = 2630.00 FEET.

****************************************************************************

…VMP - Hydrology & Hydraulic Report - Final.docx page 69

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
FLOW PROCESS FROM NODE 3.20 TO NODE 3.20 IS CODE = 10 ---------------------------------------------------------------------------- >>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 187.00 DOWNSTREAM(FEET) = 54.80 FLOW LENGTH(FEET) = 1085.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 6.0 INCH PIPE IS 2.8 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 11.16
ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 1.00
PIPE TRAVEL TIME(MIN.) = 1.62 Tc(MIN.) = 8.30
LONGEST FLOWPATH FROM NODE 3.04 TO NODE 3.07 = 1360.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 70

…VMP - Hydrology & Hydraulic Report - Final.docx page 71

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 204.00
DOWNSTREAM ELEVATION(FEET) = 178.00
ELEVATION DIFFERENCE(FEET) = 26.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.239
SUBAREA RUNOFF(CFS) = 0.20
TOTAL AREA(ACRES) = 0.11 TOTAL RUNOFF(CFS) = 0.20

…VMP - Hydrology & Hydraulic Report - Final.docx page 72

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.505
50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.302
SUBAREA RUNOFF(CFS) = 0.81
TOTAL AREA(ACRES) = 0.54 TOTAL RUNOFF(CFS) = 0.81

…VMP - Hydrology & Hydraulic Report - Final.docx page 73

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.505
50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.302
SUBAREA RUNOFF(CFS) = 0.45
TOTAL AREA(ACRES) = 0.30 TOTAL RUNOFF(CFS) = 0.45

** MAIN STREAM CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 14.52 13.24 3.233 12.75
LONGEST FLOWPATH FROM NODE 5.05 TO NODE 5.04 = 1560.00 FEET.

** MEMORY BANK # 1 CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 19.58 13.66 3.168 17.51
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.04 = 1625.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 74

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
** PEAK FLOW RATE TABLE **
STREAM RUNOFF Tc INTENSITY
NUMBER (CFS) (MIN.) (INCH/HOUR)
1 33.49 13.24 3.233
2 33.81 13.66 3.168

COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS:

PEAK FLOW RATE(CFS) = 33.81 Tc(MIN.) = 13.66
TOTAL AREA(ACRES) = 30.3

**************************************************************************** FLOW PROCESS FROM NODE 5.04 TO NODE 5.04 IS CODE = 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 218.00 DOWNSTREAM(FEET) = 103.50 CHANNEL LENGTH THRU SUBAREA(FEET) = 780.00 CHANNEL SLOPE = 0.1468 NOTE: CHANNEL FLOW OF 1. CFS WAS ASSUMED IN VELOCITY ESTIMATION NOTE: CHANNEL SLOPE OF .1 WAS ASSUMED IN VELOCITY ESTIMATION CHANNEL FLOW THRU SUBAREA(CFS) = 0.29
FLOW VELOCITY(FEET/SEC) = 4.74 (PER LACFCD/RCFC&WCD HYDROLOGY MANUAL)

…VMP - Hydrology & Hydraulic Report - Final.docx page 75

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
TRAVEL TIME(MIN.) = 2.74 Tc(MIN.) = 9.01
LONGEST FLOWPATH FROM NODE 5.09 TO NODE 5.11 = 880.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 76

…VMP - Hydrology & Hydraulic Report - Final.docx page 77

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
**************************************************************************** FLOW PROCESS FROM NODE 5.12 TO NODE 5.08 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 90.00 DOWNSTREAM(FEET) = 72.60 FLOW LENGTH(FEET) = 150.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 21.0 INCH PIPE IS 12.9 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 27.95
ESTIMATED PIPE DIAMETER(INCH) = 21.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 43.38
PIPE TRAVEL TIME(MIN.) = 0.09 Tc(MIN.) = 14.27
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.20 = 2265.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 78

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
>>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 78.80 DOWNSTREAM(FEET) = 72.60 FLOW LENGTH(FEET) = 90.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 18.0 INCH PIPE IS 10.8 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 19.27
ESTIMATED PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 21.33
PIPE TRAVEL TIME(MIN.) = 0.08 Tc(MIN.) = 7.69

…VMP - Hydrology & Hydraulic Report - Final.docx page 79

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
LONGEST FLOWPATH FROM NODE 5.16 TO NODE 5.20 = 810.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ GENERAL COMMERCIAL RUNOFF COEFFICIENT = .8200
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 95
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 126.90
DOWNSTREAM ELEVATION(FEET) = 126.10
ELEVATION DIFFERENCE(FEET) = 0.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 4.063
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 56.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.060
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.50
TOTAL AREA(ACRES) = 0.10 TOTAL RUNOFF(CFS) = 0.50

…VMP - Hydrology & Hydraulic Report - Final.docx page 80

** MAIN STREAM CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 12.11 9.82 3.921 3.75
LONGEST FLOWPATH FROM NODE 5.31 TO NODE 5.20 = 1510.00 FEET.

** MEMORY BANK # 1 CONFLUENCE DATA **

…VMP - Hydrology & Hydraulic Report - Final.docx page 81

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 57.70 14.27 3.082 50.01
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.20 = 2265.00 FEET.

** PEAK FLOW RATE TABLE **
STREAM RUNOFF Tc INTENSITY
NUMBER (CFS) (MIN.) (INCH/HOUR)
1 51.83 9.82 3.921
2 67.22 14.27 3.082

COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS:

PEAK FLOW RATE(CFS) = 67.22 Tc(MIN.) = 14.27
TOTAL AREA(ACRES) = 53.8

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.660
RESIDENTIAL (1. DU/AC OR LESS) RUNOFF COEFFICIENT = .4100 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 82
AREA-AVERAGE RUNOFF COEFFICIENT = 0.4026

…VMP - Hydrology & Hydraulic Report - Final.docx page 82

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA AREA(ACRES) = 1.20 SUBAREA RUNOFF(CFS) = 2.29 TOTAL AREA(ACRES) = 1.4 TOTAL RUNOFF(CFS) = 2.57 TC(MIN.) = 7.51

**************************************************************************** FLOW PROCESS FROM NODE 6.03 TO NODE 6.20 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 50 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.739
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 7.02 SUBAREA RUNOFF(CFS) = 9.19 TOTAL AREA(ACRES) = 7.2 TOTAL RUNOFF(CFS) = 9.38 TC(MIN.) = 10.57
============================================================================ ============================================================================

END OF RATIONAL METHOD ANALYSIS

…VMP - Hydrology & Hydraulic Report - Final.docx page 83

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
Existing 100-Year Storm Event Hydrology
____________________________________________________________________________ ****************************************************************************

Analysis prepared by:

civTEC
999 Corporate Dr., Suite 100
Ladera Ranch, CA 92694
ph: 949.463.8822

************************** DESCRIPTION OF STUDY ************************** * VETERANS MEMORIAL PARK * * EXISTING CONDITION * * 100-YEAR STORM EVENT * **************************************************************************

FILE NAME: VMP_E100.DAT
TIME/DATE OF STUDY: 16:40 01/22/2023
---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION:
---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA

USER SPECIFIED STORM EVENT(YEAR) = 100.00
6-HOUR DURATION PRECIPITATION (INCHES) = 2.700
SPECIFIED MINIMUM PIPE SIZE(INCH) = 12.00
SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING

GLOBAL STREET FLOW-DEPTH CONSTRAINTS:

1. Relative Flow-Depth = 1.00 FEET
as (Maximum Allowable Street Flow Depth) - (Top-of-Curb)

2. (Depth)*(Velocity) Constraint = 10.0 (FT*FT/S)
*SIZE PIPE WITH A FLOW CAPACITY GREATER THAN
OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.*

**************************************************************************** FLOW PROCESS FROM NODE 1.10 TO NODE 1.15 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<<
============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 108.00
DOWNSTREAM ELEVATION(FEET) = 93.00
ELEVATION DIFFERENCE(FEET) = 15.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.150
SUBAREA RUNOFF(CFS) = 0.26
TOTAL AREA(ACRES) = 0.12 TOTAL RUNOFF(CFS) = 0.26

…VMP - Hydrology & Hydraulic Report - Final.docx page 84

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS

**************************************************************************** FLOW PROCESS FROM NODE 1.15 TO NODE 1.20 IS CODE = 52 ---------------------------------------------------------------------------- >>>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 268.00
DOWNSTREAM ELEVATION(FEET) = 258.00
ELEVATION DIFFERENCE(FEET) = 10.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.150
SUBAREA RUNOFF(CFS) = 0.24
TOTAL AREA(ACRES) = 0.11 TOTAL RUNOFF(CFS) = 0.24

…VMP - Hydrology & Hydraulic Report - Final.docx page 85

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS

…VMP - Hydrology & Hydraulic Report - Final.docx page 86

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.495
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 0.90 SUBAREA RUNOFF(CFS) = 1.73 TOTAL AREA(ACRES) = 1.0 TOTAL RUNOFF(CFS) = 1.94 TC(MIN.) = 7.46

…VMP - Hydrology & Hydraulic Report - Final.docx page 87

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
S.C.S. CURVE NUMBER (AMC II) = 96
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 126.90
DOWNSTREAM ELEVATION(FEET) = 126.10
ELEVATION DIFFERENCE(FEET) = 0.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 3.627
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 56.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 7.114
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.60
TOTAL AREA(ACRES) = 0.10 TOTAL RUNOFF(CFS) = 0.60

…VMP - Hydrology & Hydraulic Report - Final.docx page 88

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
GIVEN PIPE DIAMETER(INCH) = 24.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 18.49
PIPE TRAVEL TIME(MIN.) = 0.12 Tc(MIN.) = 8.91
LONGEST FLOWPATH FROM NODE 5.30 TO NODE 5.50 = 1507.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.50 TO NODE 5.40 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 148.00 DOWNSTREAM(FEET) = 108.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 290.00 CHANNEL SLOPE = 0.1379 NOTE: CHANNEL FLOW OF 1. CFS WAS ASSUMED IN VELOCITY ESTIMATION NOTE: CHANNEL SLOPE OF .1 WAS ASSUMED IN VELOCITY ESTIMATION CHANNEL FLOW THRU SUBAREA(CFS) = 0.26
FLOW VELOCITY(FEET/SEC) = 4.74 (PER LACFCD/RCFC&WCD HYDROLOGY MANUAL) TRAVEL TIME(MIN.) = 1.02 Tc(MIN.) = 7.29
LONGEST FLOWPATH FROM NODE 6.10 TO NODE 6.20 = 390.00 FEET.

****************************************************************************

…VMP - Hydrology & Hydraulic Report - Final.docx page 89

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
FLOW PROCESS FROM NODE 6.20 TO NODE 6.20 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.389
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 7.02 SUBAREA RUNOFF(CFS) = 10.78 TOTAL AREA(ACRES) = 7.2 TOTAL RUNOFF(CFS) = 11.01 TC(MIN.) = 10.57
============================================================================ ============================================================================

END OF RATIONAL METHOD ANALYSIS

…VMP - Hydrology & Hydraulic Report - Final.docx page 90

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
Proposed 100-Year Storm Event Hydrology
____________________________________________________________________________ ****************************************************************************

Analysis prepared by:

civTEC
999 Corporate Dr., Suite 100
Ladera Ranch, CA 92694
ph: 949.463.8822

************************** DESCRIPTION OF STUDY ************************** * VETERANS MEMORIAL PARK * * PROPOSED CONDITION * * 100-YEAR STORM EVENT * **************************************************************************

FILE NAME: VMP_P100.DAT
TIME/DATE OF STUDY: 09:53 07/04/2024
---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION:
---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA

USER SPECIFIED STORM EVENT(YEAR) = 100.00
6-HOUR DURATION PRECIPITATION (INCHES) = 2.700
SPECIFIED MINIMUM PIPE SIZE(INCH) = 4.00
SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF- CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING

WIDTH CROSSFALL IN- / OUT-/PARK- HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) === ===== ========= ================= ====== ===== ====== ===== ======= 1 26.0 10.0 0.020/0.020/0.020 0.50 1.50 0.0312 0.167 0.0150

GLOBAL STREET FLOW-DEPTH CONSTRAINTS:

1. Relative Flow-Depth = 0.00 FEET
as (Maximum Allowable Street Flow Depth) - (Top-of-Curb)

2. (Depth)*(Velocity) Constraint = 6.0 (FT*FT/S)
*SIZE PIPE WITH A FLOW CAPACITY GREATER THAN
OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.*

**************************************************************************** FLOW PROCESS FROM NODE 1.01 TO NODE 1.02 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<<
============================================================================ LAWNS, GOLF COURSES, ETC. GOOD COVER RUNOFF COEFFICIENT = .3500 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 80
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 91.80
DOWNSTREAM ELEVATION(FEET) = 82.00
ELEVATION DIFFERENCE(FEET) = 9.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.309
100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.123
SUBAREA RUNOFF(CFS) = 0.32
TOTAL AREA(ACRES) = 0.15 TOTAL RUNOFF(CFS) = 0.32

…VMP - Hydrology & Hydraulic Report - Final.docx page 91

…VMP - Hydrology & Hydraulic Report - Final.docx page 92

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
ELEVATION DIFFERENCE(FEET) = 2.60
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 2.625
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 76.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 7.114
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.31
TOTAL AREA(ACRES) = 0.05 TOTAL RUNOFF(CFS) = 0.31

…VMP - Hydrology & Hydraulic Report - Final.docx page 93

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
ESTIMATED PIPE DIAMETER(INCH) = 9.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 3.84
PIPE TRAVEL TIME(MIN.) = 0.10 Tc(MIN.) = 2.90
LONGEST FLOWPATH FROM NODE 2.01 TO NODE 2.20 = 240.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 3.01 TO NODE 3.02 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 82.50 DOWNSTREAM(FEET) = 45.50 FLOW LENGTH(FEET) = 715.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 18.0 INCH PIPE IS 13.2 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 17.61
ESTIMATED PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 24.53
PIPE TRAVEL TIME(MIN.) = 0.68 Tc(MIN.) = 13.52
LONGEST FLOWPATH FROM NODE 3.01 TO NODE 3.20 = 2630.00 FEET.

****************************************************************************

…VMP - Hydrology & Hydraulic Report - Final.docx page 94

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
FLOW PROCESS FROM NODE 3.20 TO NODE 3.20 IS CODE = 10 ---------------------------------------------------------------------------- >>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 187.00 DOWNSTREAM(FEET) = 54.80 FLOW LENGTH(FEET) = 1085.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 6.0 INCH PIPE IS 3.1 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 11.63
ESTIMATED PIPE DIAMETER(INCH) = 6.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 1.18
PIPE TRAVEL TIME(MIN.) = 1.55 Tc(MIN.) = 8.22
LONGEST FLOWPATH FROM NODE 3.04 TO NODE 3.07 = 1360.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 95

…VMP - Hydrology & Hydraulic Report - Final.docx page 96

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
S.C.S. CURVE NUMBER (AMC II) = 83
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 204.00
DOWNSTREAM ELEVATION(FEET) = 178.00
ELEVATION DIFFERENCE(FEET) = 26.00
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.267
WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.150
SUBAREA RUNOFF(CFS) = 0.24
TOTAL AREA(ACRES) = 0.11 TOTAL RUNOFF(CFS) = 0.24

…VMP - Hydrology & Hydraulic Report - Final.docx page 97

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.505
100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.050
SUBAREA RUNOFF(CFS) = 0.95
TOTAL AREA(ACRES) = 0.54 TOTAL RUNOFF(CFS) = 0.95

…VMP - Hydrology & Hydraulic Report - Final.docx page 98

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.505
100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.050
SUBAREA RUNOFF(CFS) = 0.53
TOTAL AREA(ACRES) = 0.30 TOTAL RUNOFF(CFS) = 0.53

** MAIN STREAM CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 17.05 13.24 3.796 12.75
LONGEST FLOWPATH FROM NODE 5.05 TO NODE 5.04 = 1560.00 FEET.

** MEMORY BANK # 1 CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 22.98 13.66 3.721 17.51
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.04 = 1625.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 99

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
** PEAK FLOW RATE TABLE **
STREAM RUNOFF Tc INTENSITY
NUMBER (CFS) (MIN.) (INCH/HOUR)
1 39.33 13.24 3.796
2 39.69 13.66 3.721

COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS:

PEAK FLOW RATE(CFS) = 39.69 Tc(MIN.) = 13.66
TOTAL AREA(ACRES) = 30.3

**************************************************************************** FLOW PROCESS FROM NODE 5.04 TO NODE 5.04 IS CODE = 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 218.00 DOWNSTREAM(FEET) = 103.50 CHANNEL LENGTH THRU SUBAREA(FEET) = 780.00 CHANNEL SLOPE = 0.1468 NOTE: CHANNEL FLOW OF 1. CFS WAS ASSUMED IN VELOCITY ESTIMATION NOTE: CHANNEL SLOPE OF .1 WAS ASSUMED IN VELOCITY ESTIMATION CHANNEL FLOW THRU SUBAREA(CFS) = 0.34
FLOW VELOCITY(FEET/SEC) = 4.74 (PER LACFCD/RCFC&WCD HYDROLOGY MANUAL)

…VMP - Hydrology & Hydraulic Report - Final.docx page 100

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
TRAVEL TIME(MIN.) = 2.74 Tc(MIN.) = 9.01
LONGEST FLOWPATH FROM NODE 5.09 TO NODE 5.11 = 880.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 101

…VMP - Hydrology & Hydraulic Report - Final.docx page 102

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
**************************************************************************** FLOW PROCESS FROM NODE 5.12 TO NODE 5.08 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 90.00 DOWNSTREAM(FEET) = 72.60 FLOW LENGTH(FEET) = 150.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 21.0 INCH PIPE IS 14.5 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 28.84
ESTIMATED PIPE DIAMETER(INCH) = 21.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 50.93
PIPE TRAVEL TIME(MIN.) = 0.09 Tc(MIN.) = 14.24
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.20 = 2265.00 FEET.

…VMP - Hydrology & Hydraulic Report - Final.docx page 103

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
>>>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 78.80 DOWNSTREAM(FEET) = 72.60 FLOW LENGTH(FEET) = 90.00 MANNING'S N = 0.011
DEPTH OF FLOW IN 18.0 INCH PIPE IS 12.1 INCHES
PIPE-FLOW VELOCITY(FEET/SEC.) = 19.93
ESTIMATED PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 25.13
PIPE TRAVEL TIME(MIN.) = 0.08 Tc(MIN.) = 7.65

…VMP - Hydrology & Hydraulic Report - Final.docx page 104

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
LONGEST FLOWPATH FROM NODE 5.16 TO NODE 5.20 = 810.00 FEET.

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 11 ---------------------------------------------------------------------------- >>>>>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY >>>>CLEAR MEMORY BANK # 1 >>>>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ GENERAL COMMERCIAL RUNOFF COEFFICIENT = .8200
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 95
INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00
UPSTREAM ELEVATION(FEET) = 126.90
DOWNSTREAM ELEVATION(FEET) = 126.10
ELEVATION DIFFERENCE(FEET) = 0.80
SUBAREA OVERLAND TIME OF FLOW(MIN.) = 4.063
WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 56.00
(Reference: Table 3-1B of Hydrology Manual)
THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 7.114
NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.

SUBAREA RUNOFF(CFS) = 0.58
TOTAL AREA(ACRES) = 0.10 TOTAL RUNOFF(CFS) = 0.58

…VMP - Hydrology & Hydraulic Report - Final.docx page 105

** MAIN STREAM CONFLUENCE DATA **
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 14.40 9.62 4.664 3.75
LONGEST FLOWPATH FROM NODE 5.31 TO NODE 5.20 = 1510.00 FEET.

** MEMORY BANK # 1 CONFLUENCE DATA **

…VMP - Hydrology & Hydraulic Report - Final.docx page 106

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
STREAM RUNOFF Tc INTENSITY AREA
NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE)
1 67.76 14.24 3.622 50.01
LONGEST FLOWPATH FROM NODE 5.01 TO NODE 5.20 = 2265.00 FEET.

** PEAK FLOW RATE TABLE **
STREAM RUNOFF Tc INTENSITY
NUMBER (CFS) (MIN.) (INCH/HOUR)
1 60.18 9.62 4.664
2 78.94 14.24 3.622

COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS:

PEAK FLOW RATE(CFS) = 78.94 Tc(MIN.) = 14.24
TOTAL AREA(ACRES) = 53.8

**************************************************************************** FLOW PROCESS FROM NODE 5.20 TO NODE 5.20 IS CODE = 12 ---------------------------------------------------------------------------- >>>>>CLEAR MEMORY BANK # 1 >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.496
RESIDENTIAL (1. DU/AC OR LESS) RUNOFF COEFFICIENT = .4100 SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 82
AREA-AVERAGE RUNOFF COEFFICIENT = 0.4026

…VMP - Hydrology & Hydraulic Report - Final.docx page 107

2.0 HYDROLOGY & HYDRAULIC CALCULATIONS
SUBAREA AREA(ACRES) = 1.20 SUBAREA RUNOFF(CFS) = 2.70 TOTAL AREA(ACRES) = 1.4 TOTAL RUNOFF(CFS) = 3.03 TC(MIN.) = 7.46

**************************************************************************** FLOW PROCESS FROM NODE 6.03 TO NODE 6.20 IS CODE = 31 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA >>>>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW) >>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS >>>>COMPUTE NATURAL VALLEY CHANNEL FLOW >>>>TRAVELTIME THRU SUBAREA >>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 4.389
OPEN BRUSH FAIR COVER RUNOFF COEFFICIENT = .3500
SOIL CLASSIFICATION IS "D"
S.C.S. CURVE NUMBER (AMC II) = 83
AREA-AVERAGE RUNOFF COEFFICIENT = 0.3500
SUBAREA AREA(ACRES) = 7.02 SUBAREA RUNOFF(CFS) = 10.78 TOTAL AREA(ACRES) = 7.2 TOTAL RUNOFF(CFS) = 11.01 TC(MIN.) = 10.57
============================================================================ ============================================================================

END OF RATIONAL METHOD ANALYSIS

Sediment Basin Sizing:

Q=CIA
Name P6 P24 D I
A 1.7 3.1 6.92 3.63
B1 1.7 3.1 2.84 6.45
B2 1.7 3.1 2.84 6.45
C1 1.7 3.1 12.85 2.44
C2 1.7 3.1 12.95 2.42
D 1.7 3.1 7.23 3.53
E1 1.7 3.1 13.49 2.36
E2 1.7 3.1 13.11 2.41
E3 1.7 3.1 9.01 3.06
E4 1.7 3.1 7.09 3.58
E5 1.7 3.1 7.92 3.33
E6 1.7 3.1 8.52 3.18
F 1.7 3.1 7.72 3.38
G 1.7 3.1 10.57 2.76
A_sediment=1.2Q/V
V=0.00028ft/s
10 year

c=0.35
Name A (acres)Q(CFS)A_sediment (sf)Basin outfallrequired storageoffsite runon A 1.32 1.68 7191 7191 7191 84.80263
B1 0.41 0.93 3967
B2 0.41 0.93 3967 7935 7935 89.07756
C1 18.11 15.44 66189 15.44
C2 18.55 15.74 67459 133649 67459 259.7296
D 0.95 1.17 5031 5031 1.17 0
E1 17.51 14.47 62021 14.47
E2 12.75 10.73 46001 10.73
E3 7.93 8.50 36441
E4 0.54 0.68 2896
E5 11.28 13.14 56331
E6 3.75 4.17 17865 221556 113533 336.9467
F 1.37 1.62 6955 6955 6955 83.39889
G 7.17 6.94 29724 29724 6.94
203074

CASQA Traditional SWPPP Template M-1 August 2023
for the 2022 CGP
Appendix M: Weather Reports
The discharger must obtain the precipitation forecast information from the National Weather Service Forecast Office ( http://forecast.weather.gov ). A printed copy with the date and time of printing should be retained in this Appendix.

CASQA Traditional SWPPP Template N-1 August 2023
for the 2022 CGP
Appendix N: Monitoring Records
Place completed BMP Inspection Forms, photographic documentation, Effluent Sampling, Receiving Water, and Dewatering Field Logs, Monitoring Exceptions, NAL Exceedance Reports, and Receiving Water Monitoring Trigger Exceptions in this appendix.

CASQA Traditional SWPPP Template O-1 August 2023
for the 2022 CGP
Appendix O: Example Storm Event Monitoring
Forms

CASQA Traditional SWPPP Template O-2 August 2023
for the 2022 CGP
Rain Gauge Log Sheet
Construction Site Name:

WDID #:

Date
(mm/dd/yy)
Time
(24-hr) Initials Rainfall Depth
(Inches) Notes:

CASQA Traditional SWPPP Template O-3 August 2023
for the 2022 CGP
Risk Level 1, 2, 3
Visual Inspection Field Log Sheet
Date and Time of Inspection: Report Date:

Inspection Type: □ Weekly □ Pre Qualifying
Precipitation
Event (QPE)
□ During QPE □ Post QPE □ Dewatering
Discharge
Site Information
Construction Site Name:

Construction stage and
completed activities:

Approximate area
of exposed site:

Weather and Observations
Date Rain Predicted to Occur: Predicted % chance of precipitation (PoP):

Predicted quantity of precipitation (QPF):

Estimate storm beginning:

(date and time)
Estimate storm
duration:_________
(hours)
Estimate time since last
storm: ________
(days or hours)
Rain gauge
reading: _______
(inches)
Observations: If yes identify location
Odors Yes □ No □
Floating material Yes □ No □
Suspended Material Yes □ No □
Sheen Yes □ No □
Discolorations Yes □ No □
Turbidity Yes □ No □
Site Inspections
Outfalls or BMPs Evaluated Deficiencies Noted
(add additional sheets or attached detailed BMP Inspection Checklists)

Photos Taken: Yes □ No □ Photo Reference IDs:

Corrective Actions Identified (note if SWPPP/REAP change is needed)

Inspector Information
Inspector Name: Inspector Title:

Signature: Date:

CASQA Traditional SWPPP Template O-4 August 2023
for the 2022 CGP
Risk Level 1, 2, 3
Effluent Sampling Field Log Sheets
Construction Site Name: Date: Time Start:

Sampler:

Sampling Event Type: □ Stormwater □ Dewatering Discharge □ Non-visible pollutant Field Meter Calibration
pH Meter ID No./Desc.:

Calibration Date/Time:

Turbidity Meter ID No./Desc.:

Calibration Date/Time:

Field pH and Turbidity Measurements
Discharge Location Description pH Turbidity Time

Grab Samples Collected
Discharge Location Description Sample Type Time

Additional Sampling Notes:

Time End:

CASQA Traditional SWPPP Template O-5 August 2023
for the 2022 CGP

Risk Level 3
Receiving Water Sampling Field Log Sheets
Construction Site Name: Date: Time Start:

Sampler:

Receiving Water Description and Observations
Receiving Water Name/ID:

Observations:

Odors Yes □ No □
Floating material Yes □ No □
Suspended Material Yes □ No □
Sheen Yes □ No □
Discolorations Yes □ No □
Turbidity Yes □ No □
Field Meter Calibration
pH Meter ID No./Desc.:

Calibration Date/Time:

Turbidity Meter ID No./Desc.:

Calibration Date/Time:

Field pH and Turbidity Measurements
Upstream Location
Type Result Time Notes
pH

Turbidity

Downstream Location
Type Result Time Notes
pH

Turbidity

Additional Sampling Notes:

Time End:

CASQA Traditional SWPPP Template O-6 August 2023
for the 2022 CGP
NAL Exceedance Evaluation Summary Report Page __ of __
Project Name
Project WDID
Project Location
Date of Exceedance
Type of Exceedance
NAL ☐ pH ☐ Turbidity
☐ Other (specify)
Measurement or
Analytical Method
☐ Field meter
(Sensitivity: )
☐ Lab method (specify)
(Minimum Level: )
(MDL: )
Calculated Daily
Average
☐ pH pH units
☐ Turbidity NTU
Rain Gauge
Measurement inches

Visual Observations
on Day of
Exceedance

CASQA Traditional SWPPP Template O-7 August 2023
for the 2022 CGP
NAL Exceedance Evaluation Summary Report Page __ of __
Description of BMPs
in Place at Time of
Event

Initial Assessment
of Cause

Corrective Actions
Taken (deployed
after exceedance)

Additional
Corrective Actions
Proposed

Report Completed
By

(Print Name, Title)
Signature

CASQA Traditional SWPPP Template O-8 August 2023
for the 2022 CGP
CHAIN-OF-CUSTODY DATE: Lab ID:

DESTINATION LAB:

REQUESTED
ANALYSIS Notes:

ATTN:

ADDRESS:

Office Phone:

Cell Phone:

SAMPLED BY:

Contact:

Project Name

Client Sample ID Sample Sample Sample Container
Date Time Matrix # Type Pres.

SENDER COMMENTS:

RELINQUISHED
BY

Signature:

Print:

Company:

Date: TIME:

LABORATORY COMMENTS: RECEIVED BY
Signature:

Print:

Company:

Date: TIME:

CASQA Traditional SWPPP Template P-1 August 2023
for the 2022 CGP
Appendix P: Field Meter Instructions

Information to be Provided by Contractor Prior to
Construction.

CASQA Traditional SWPPP Template Q-1 August 2023
for the 2022 CGP
Appendix Q: Supplemental Information

Information to be Provided by Contractor Prior to
Construction.

CASQA Traditional SWPPP Template R-1 August 2023
for the 2022 CGP
Appendix R: Active Treatment System and
Passive Treatment Plans

Information to be Provided by Contractor Prior to
Construction.

CASQA Traditional SWPPP Template S-1 August 2023
for the 2022 CGP
Appendix S: Construction General Permit
Copies of the Construction Stormwater General Permit may be downloaded from the State Water Board website at:
http://www.waterboards.ca.gov/water_issues/programs/stormwater/construction.shtml .

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CALIFORNIA STATE WATER RESOURCES CONTROL BOARD
1001 I Street Sacramento, CA 95814
https://www.waterboards.ca.gov

NATIONAL POLLUTANT DISCHARGE ELIMINATION SYSTEM (NPDES)

GENERAL PERMIT FOR STORMWATER DISCHARGES ASSOCIATED WITH

CONSTRUCTION AND LAND DISTURBANCE ACTIVITIES
(GENERAL PERMIT)

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IT IS HEREBY ORDERED that this Order supersedes Order 2009-0009-DWQ as amended by Order 2010-0014-DWQ and 2012-0006-DWQ except for: (1) the requirement to submit annual reports by September 1, 2023, (2) enforcement purposes, and (3) as set forth in Section III.C of this Order. The discharger shall comply with the requirements in this Order to meet the provisions contained in Division 7 of the California Water Code (commencing with § 13000) and regulations adopted thereunder, and the provisions of the federal Clean Water Act and regulations and guidelines adopted thereunder.

IT IS ALSO HEREBY ORDERED that on or after December 17, 2022, a discharger deploying Executive Order N-73-20 may obtain regulatory coverage through the statewide programmatic permitting option in Section III.B.4 under Order 2009-0009-DWQ as amended by Orders 2010-0014-DWQ and 2012- 0006-DWQ until September 1, 2023.

This Order was adopted by the State Water Resources
Control Board on: September 8, 2022
This Order shall become effective on: September 1, 2023 The statewide programmatic permitting option per Section III.B.4 of this Order shall become effective on: December 17, 2022 This Order shall expire on: August 31, 2028

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I, Jeanine Townsend, Clerk to the Board, do hereby certify that this Order with all attachments is a full, true, and correct copy of an Order adopted by the State Water Resources Control Board, on September 8, 2022.

AYE: Chair E. Joaquin Esquivel
Board Member Sean Maguire
Board Member Laurel Firestone
Board Member Nichole Morgan
NAY: None
ABSENT: Vice Chair Dorene D’Adamo
ABSTAIN: None

for
Jeanine Townsend
Clerk to the Board

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Table of Contents
I. FINDINGS ................................................................................................ 1 II. SCOPE OF GENERAL PERMIT COVERAGE ........................................ 8 III. OBTAINING, REVISING, AND TERMINATING PERMIT COVERAGE. 12 IV. PERMIT REQUIREMENTS .................................................................... 23 V. SITE ROLES AND PERSONNEL .......................................................... 36 VI. STANDARD PROVISIONS .................................................................... 42 VII. REGIONAL WATER BOARD AUTHORITIES ....................................... 49

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LIST OF ATTACHMENTS
Attachment A Acronyms and Terms
Attachment B Glossary
Attachment C Contacts
Attachment D Traditional Construction Risk Level Requirements Attachment D.1 Risk Determination Worksheet
Attachment D.2 Permit Registration Document Requirements Attachment E Linear Underground and Overhead Project Requirements Attachment E.1 Linear Underground and Overhead Project Area or Segment Area Type Determination
Attachment E.2 Permit Registration Document Requirements for Linear Underground and Overhead Projects
Attachment F Active Treatment System Requirements
Attachment G Requirements for the Use of Passive Treatment Technologies Attachment H Total Maximum Daily Load Implementation Requirements Applicable to Construction Stormwater Discharges
Attachment I Requirements for Dischargers Granted a California Ocean Plan Exception for Discharges to Areas of Special Biological Significance
Attachment J Dewatering Requirements

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I. FINDINGS
The State Water Resources Control Board (State Water Board) finds that:

1. The Federal Water Pollution Control Act, also referred to as the Clean Water Act, prohibits certain discharges of stormwater containing pollutants to waters of the United States except in compliance with a National Pollutant Discharge Elimination System (NPDES) permit (Title 33 United States Code (U.S.C.) §§ 1311 and 1342(p); also referred to as Clean Water Act §§ 301 and 402(p)).

The United States Environmental Protection Agency (U.S. EPA) promulgates federal regulations to implement the Clean Water Act’s mandate to control pollutants in stormwater runoff discharges. (Title 40 Code of Federal Regulations (CFR) Parts 122, 123, and 124). The federal statutes and regulations require discharges to waters of the United States comprised of stormwater associated with construction activity to obtain NPDES permit coverage (except operations that result in disturbance of less than one acre of total land area and that are not part of a larger common plan of development or sale). Construction activity includes, but is not limited to, clearing, demolition, grading, excavation, and other land disturbance activities. The NPDES permit shall require implementation of Best Available Technology Economically Achievable (BAT) and Best Conventional Pollutant Control Technology (BCT) to reduce or eliminate pollutants in stormwater runoff. The NPDES permit shall also include any additional requirements necessary to achieve applicable water quality standards.

2. Consistent with Water Code, § 13374, this NPDES permit also serves as waste discharge requirements for discharges of pollutants in stormwater runoff (stormwater discharges) associated with construction and land disturbance activities and is hereinafter referred to as General Permit.

3. A “discharger” is a person, as defined in Water Code § 13050(c), which includes companies and governmental bodies, subject to this General Permit who is responsible for compliance with this General Permit. The discharger designates the Legally Responsible Person(s) to serve as a primary signatory when required to sign, certify, and submit documents or information for this General Permit. The Legally Responsible Person(s) may also designate a Duly Authorized Representative(s) to sign, certify, and submit documents or information for this General Permit. “Discharger” and the designated “Duly Authorized Representative” are further defined in Attachment B of this General Permit.

4. This General Permit regulates discharges to waters of the United States from stormwater and authorized non-stormwater associated with construction activity from sites that disturb one or more acres of land surface, or that are part of a common plan of development or sale that disturbs more than one acre of land surface.

5. This General Permit regulates discharges to waters of the United States from stormwater and authorized non-stormwater associated with construction activities

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from all linear underground and overhead projects resulting in the disturbance of greater than or equal to one acre (Attachment E).

6. This General Permit does not preempt or supersede the authority of local stormwater management agencies to prohibit, restrict, or control stormwater discharges to municipal separate storm sewer systems or other watercourses within their jurisdictions.

7. This action to adopt a general NPDES permit is exempt from the provisions of Chapter 3 of the California Environmental Quality Act (Public Resources Code § 21100, et seq.), pursuant to § 13389 of the California Water Code.

8. Regional Water Quality Control Boards (Regional Water Boards) establish water quality standards in water quality control plans. The State Water Board establishes water quality standards in various statewide water quality control plans, including the California Ocean Plan and the forthcoming Inland Surface Waters, Enclosed Bays, and Estuaries of California Plan. U.S. EPA establishes water quality standards in the National Toxic Rule and the California Toxic Rule.

9. Pursuant to 40 Code of Federal Regulations § 131.12 and State Water Board Resolution No. 68-16 (antidegradation policy), which incorporates applicable requirements of § 131.12, in high quality waters, discharges may not unreasonably affect beneficial uses, result in water quality less than the quality specified by water quality objectives, or cause a pollution or nuisance, except as allowed under the antidegradation policy. The federal antidegradation policy requires that “existing instream uses and the level of water quality necessary to protect the existing uses” are maintained and protected. If the baseline quality of a waterbody for a given constituent “exceeds levels necessary to support propagation of fish, shellfish, and wildlife and recreation in and on the water, that quality shall be maintained and protected” through the requirements of this Order unless the State Water Board makes findings that: (1) any lowering of the water quality is “necessary to accommodate important economic or social development in the area in which the waters are located”; (2) “water quality adequate to protect existing uses fully” is assured; and (3) “the highest statutory and regulatory requirements for all new and existing point sources and all cost-effective and reasonable best management practices for nonpoint source control” are achieved. For high quality waters, Resolution No. 68-16 requires findings that any lowering of water quality is “consistent with the maximum benefit to the people of the State” and “will not unreasonably affect present and anticipated beneficial use of such water and will not result in water quality less than that prescribed in the policies” and further that the discharge is subject to “waste discharge requirements which will result in the best practicable treatment or control of the discharge.”

10. The State Water Board finds that the permitted discharges authorized by this Order are consistent with the antidegradation provision of 40 CFR §131.12 and State Water Board Resolution No. 68-16, as set forth in Section I.H.2 in the Fact Sheet.

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11. This General Permit serves as an NPDES permit in compliance with Clean Water Act § 402 and will be effective on September 1, 2023, except for the statewide programmatic permitting option per Section III.B.4 of this Order which will go into effect on December 17, 2022, provided the Regional Administrator of the U.S. EPA has no objection. If the U.S. EPA Regional Administrator objects to its issuance, this General Permit will not become effective until such objection is withdrawn.

12. The Regional Water Boards and the State Water Board, collectively referred to as the Water Boards, shall enforce the provisions herein following adoption and upon the effective date of this General Permit.

13. Stormwater discharges from dredge spoil placement that occur outside of waters of the state (upland sites) and that disturb one or more acres of land surface from construction activity are covered by this General Permit. This General Permit does not cover the discharge of dredged or fill material to waters of the state.

Construction projects that include the discharge of dredged or fill material to waters of the state should contact the applicable Regional Water Board to obtain authorization for the discharge of dredged or fill material to waters of the state.

14. The discharge of dredged or fill material to a water of the United States is regulated by the United States Army Corps of Engineers under Clean Water Act § 404, and by the Water Boards under Clean Water Act § 401. The discharge of dredged or fill material to a water outside of federal jurisdiction may be regulated by the Water Boards under the Porter-Cologne Water Quality Control Act. This General Permit does not authorize discharges of fill or dredged material regulated by the U.S. Army Corps of Engineers under CWA § 404 and does not constitute a waiver of water quality certification under CWA § 401.

15. Compliance with requirements contained in this General Permit does not supersede or constitute compliance with other regulatory requirements also applicable to discharges regulated by this General Permit, including waste discharge prohibitions in regional and statewide water quality control plans.

16. The State Water Board heard and considered all comments and testimony in a public hearing on August 4, 2021, as publicly noticed in accordance with state and federal laws and regulations. The State Water Board has prepared written responses to all significant comments.

17. The Homeland Security Act of 2002 (U.S. 116 STAT. 2135 and Title 6 U.S. Code Chapter 1 § 101) requires any information provided to the Water Boards per a regulatory action taken by the Water Boards shall comply with the Homeland Security Act and other federal law that address security in the United States; the discharger should not submit any information that does not comply.

18. The discharger is required to comply with this General Permit’s conditions for all discharges associated with stormwater from construction activity and authorized non-stormwater discharges by this General Permit or another NPDES permit

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issued by the State Water Board or a Regional Water Board. All other discharges are prohibited by this General Permit.

19. Unauthorized non-stormwater discharges are prohibited, including improper dumping, spills, or leakage from storage tanks or transfer areas. Non-stormwater discharges may contribute significant pollutant loads to receiving waters.

20. All discharges which contain a hazardous substance in excess of reportable quantities established in 40 Code of Federal Regulations §§ 117.3 and 302.4, are prohibited unless a separate NPDES permit has been issued to regulate those discharges.

21. Stormwater that is exposed to by-products and waste products resulting from demolition activities may transport and discharge pollutants off-site and into receiving waters.

22. In 2008, the State Water Board and the California Stormwater Quality Association (CASQA) led a group of stakeholders in developing and establishing the Construction General Permit Training Team (CGPTT). Subsequently, the CGPTT developed the training program and certification process for Qualified Stormwater Pollution Prevention Plan (SWPPP) Developer (QSD) and the Qualified SWPPP Practitioner (QSP) conducting work required by this General Permit. In 2010, CASQA and the State Water Board entered into a Memorandum of Agreement to document their respective understandings, roles, and responsibilities for the implementation of the QSD/QSP training program. The Memorandum of Agreement notes that the CASQA QSD/QSP Training Program constitutes a State Water Board-approved training course pursuant to the Construction Stormwater General Permit. The Memorandum of Agreement also documents that CASQA will continue to lead the QSD/QSP training program, with guidance from the CGPTT.

23. Per the Memorandum of Agreement, CASQA is responsible for qualifying and overseeing Trainers of Record who deliver the official QSD/QSP training program curricula in a manner consistent with the standards established by the CGPTT.

24. All California professional engineering, land surveying, and geology work is licensed by the Board for Professional Engineers, Land Surveyors, and Geologists.1 Pursuant to the Professional Engineers Act (Bus. and Prof. Code § 6700, et seq.), all engineering work is required to be performed by a California licensed professional engineer. Pursuant to the Profession Land Surveyor’s Act (Bus. and Prof. Code §§ 8700 – 8805), all land surveying work is required to be performed by a California licensed profession land surveyor. Pursuant to the Professional Geologist and Geophysicist’s Act (Bus. and Prof. Code §§ 7800 –

1 Department of Consumer Affairs, California Board for Professional Engineers, Land Surveyors, and Geologists website https://www.bpelsg.ca.gov/ > [as of July 2022]

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7887), all geological work is required to be performed by a California licensed professional geologist.

25. Precipitation events can occur at any time of the year in California. On-site stormwater management is necessary throughout the entire year to ensure sites implement adequate erosion and sediment controls prior to the onset of a precipitation event, even if construction is planned only during the typically dry season.

26. Soil particles smaller than 0.02 millimeters (mm) (i.e., finer than medium silt) do not settle easily using conventional measures for sediment control (i.e., sediment basins). Fine particles discharged into surface waters cause downstream impacts to beneficial uses in the receiving water. Actively treating construction stormwater discharges with properly operated and maintained active treatment systems can reduce the turbidity level and sediment concentration in the discharge to levels that comply with receiving water limitations.

27. The State Water Board convened a Blue-Ribbon Panel (Panel) of stormwater experts that submitted a report entitled “The Feasibility of Numeric Effluent Limits Applicable to Discharges of Stormwater Associated with Municipal, Industrial and Construction Activities,” dated June 19, 2006. The Panel concluded that numeric effluent limitations or numeric action levels are technically feasible to regulate construction stormwater discharges. The Panel concluded that numeric effluent limitations are feasible for discharges from sites that utilize an active treatment system. The Panel also concluded that numeric action levels are likely to be more commonly feasible. The previous permit (Order 2009-0009-DWQ, as amended by Orders 2010-0014-DWQ and 2012-0006-DWQ) includes numeric action levels for pH and turbidity, and specific numeric effluent limitations for active treatment system discharges. The Panel was not asked to address requirements specific to the implementation of Total Maximum Daily Loads (TMDL) with assigned waste load allocations for construction stormwater sources.

28. The purpose of numeric action levels and associated monitoring requirements is to provide operational information regarding the performance of the site control measures used to minimize the discharge of pollutants and to protect receiving water beneficial uses from the adverse effects of construction-related stormwater and authorized non-stormwater discharges. Upon exceedance of a numeric action level, the discharger must take necessary corrective actions, including but not limited to maintenance, replacement, and/or installation of new best management practices. This General Permit relies on dischargers to implement an iterative process for best management practice to protect water quality.

Failure to implement corrective actions in response to a numeric action level exceedance is a violation of this General Permit.

29. This General Permit requires compliance with receiving water limitations based on water quality standards established in regional or statewide water quality control plans. One of the receiving water limitations requires that construction

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stormwater discharges and authorized non-stormwater discharges not cause or contribute to an exceedance of applicable water quality standards. Water quality standards apply to the quality of the receiving water, not the quality of the construction stormwater discharge. Therefore, compliance with the receiving water limitations generally cannot be determined solely by the effluent water quality characteristics. If any discharger’s stormwater discharge causes or contributes to an exceedance of water quality standards, that discharger must implement additional BMPs or other control measures in order to attain compliance with the receiving water limitation. Compliance with water quality standards may, in some cases, require dischargers to implement controls that are more protective than controls implemented solely to comply with the technology-based requirements in this General Permit.

30. A Total Maximum Daily Load is the sum of the allowable loads of a single pollutant from all contributing point sources (waste load allocations) and non- point sources (load allocations), plus the contribution from background sources (40 Code of Federal Regulations § 130.2(i)). Discharges of stormwater from construction activities are considered point source discharges, and therefore must comply with NPDES permit requirements translated to be “consistent with the assumptions and requirements of any available waste load allocation for the discharge prepared by the state and approved by U.S. EPA pursuant to 40 Code of Federal Regulations § 130.7” (40 Code of Federal Regulations § 122.44 (d)(1)(vii)). In addition, Water Code § 13263, subdivision (a), requires that waste discharge requirements implement any relevant water quality control plans. Many TMDLs in water quality control plans include implementation requirements that may be translated into General Permit requirements and TMDL-specific numeric action levels and numeric effluent limitations.

31. Areas of Special Biological Significance are defined in the California Ocean Plan as “those areas designated by the State Water Board as ocean areas requiring protection of species or biological communities to the extent that alteration of natural water quality is undesirable.” The California Ocean Plan prohibits the discharge of waste to Areas of Special Biological Significance unless identified in a State Water Board-approved exception.

32. The California Ocean Plan authorizes the State Water Board to grant an exception to California Ocean Plan provisions where the State Water Board determines that the exception will not compromise protection of ocean waters for beneficial uses and the public interest will be served.

33. On March 20, 2012, the State Water Board adopted Resolutions 2012-0012 and Resolution 2012-0031, which contain exceptions to the California Ocean Plan for specific discharges of stormwater and non-point sources. This resolution also contains the special protections that are to be implemented for those discharges to Areas of Special Biological Significance.

34. Dischargers are only allowed to discharge to an Area of Special Biological Significance when in compliance with Areas of Special Biological Significance-

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specific requirements in a State Water Board-provided exception to the California Ocean Plan granted to the specific discharger.

35. On August 19, 2014, the U.S. EPA adopted regulations requiring all NPDES permits to include requirements to implement sufficiently sensitive test methods.

This General Permit requires all laboratory analyses to be sufficiently sensitive and conducted according to test procedures under 40 Code of Federal Regulations Part 136. All analytical results less than the minimum level (reporting limit), as reported by the laboratory, will be assigned a value of zero (0) for any calculations required by this permit (e.g., numeric action level and numeric effluent limitation exceedance determinations), so long as a sufficiently sensitive test method was used as evidenced by the reported method detection limit and minimum level.

36. Specific types of passive treatment used in combination with other best management practices (BMPs) can prevent or reduce the discharge of fine particles from certain construction activities when implemented correctly.

37. Passive treatment is the application of natural or synthetic chemicals and products to reduce turbidity in discharges through coagulation and flocculation.

Passive treatment does not rely on computerized, enclosed systems with pumps, filters, and real-time controls. Passive treatment may include pumps where they are necessary to move water around the site. The discharge of chemicals used in passive treatment can potentially cause or contribute to acute and chronic toxicity to aquatic life in receiving waters, potentially resulting in an exceedance of narrative or numeric water quality objectives in regional or statewide water quality control plans.

38. State Water Board Resolution 2005-0006, "Resolution Adopting the Concept of Sustainability as a Core Value for State Water Board Programs and Directing its Incorporation," and Resolution No. 2008-0030, “Requiring Sustainable Water Resources Management,” include performance standards for post-construction BMPs. The standards include the use of permanent post-construction BMPs that manage stormwater runoff rates to match pre-construction project site hydrology, and to sustain and ensure the physical structure and biological integrity of aquatic ecosystems in the receiving waters. This “runoff reduction” approach is analogous in principle to low impact development and is proven to protect watersheds and waterbodies from hydrologic-based adverse changes and pollution impacts associated with the post-construction landscape.

39. Linear underground and overhead projects are not subject to post-construction requirements due to the nature of their construction to return project sites to pre- construction conditions.

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IT IS HEREBY ORDERED that all dischargers subject to this General Permit shall comply with the following conditions and requirements (including all conditions and requirements as set forth in the Attachments of this Order)2: State Water Board Order 2009-009-DWQ as amended by Orders 2010-0014-DWQ and 2012-0006-DWQ (previous permit) is superseded as of the effective date of this General Permit except for enforcement purposes, the Annual Report required to be submitted by September 1, 2023, and as set forth in Section III.C.

II. SCOPE OF GENERAL PERMIT COVERAGE
II.A. Traditional Construction Activities Subject to this General Permit This General Permit covers construction projects that include construction or land disturbance activities that result in a disturbance of one or more acres, or less than one acre but are part of a larger common plan of development or sale that totals one or more acres of land disturbance, such as the following:

1. Construction activity that includes, but is not limited to, clearing, grading, excavation, stockpiling, and demolition activities that expose or disturb soil.

2. Construction activity related to residential, commercial, or industrial development on lands currently used for agriculture including, but not limited to, the construction of buildings related to agriculture that are considered industrial pursuant to U.S. EPA regulations, such as dairy barns or food processing facilities.

3. Construction activity associated with oil and gas exploration, production, processing, or treatment operations or transmission facilities pursuant to 40 Code of Federal Regulations § 122.26(c)(1)(iii), which:
a. Had a discharge of stormwater resulting in the discharge of a reportable quantity for which notification is or was required pursuant to 40 Code of Federal Regulations §§ 117.21 or 302.6 at any time since November 16, 1987;
b. Had a discharge of stormwater resulting in the discharge of a reportable quantity for which notification is or was required pursuant to Code of Federal Regulations § 110.6 at any time since November 16, 1987; or c. Contributes to a violation of a water quality standard.

II.B. Traditional Construction Activities Not Subject to this General Permit This General Permit does not apply to the following construction activity:

1. Routine maintenance. Routine maintenance is defined as activities intended to maintain the original line and grade, hydraulic capacity and/or purpose of

2 The attachments are part of this General Permit; the attachments are not separate orders or documents that will be updated independently by the State Water Board.

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the facility. This General Permit further defines routine maintenance for road and highway projects as the replacement of the structural section, but not when the activity exposes the underlying soil or erodible subgrade. The road surface and base are not part of the subgrade. As such, those portions of a project that remove the paved road surface and base down to the erodible subgrade and/or underlying soil would not be considered routine maintenance.

2. Disturbances to land surfaces solely related to growing crops or agricultural operations such as disking, harrowing, terracing, and leveling, and soil preparation.

3. Discharges of stormwater from areas on tribal lands; construction on tribal lands is regulated by a federal permit.

4. Discharges of stormwater within the Lake Tahoe Hydrologic Unit. The Lahontan Regional Water Board has adopted its own permit to regulate stormwater discharges from construction activity in the Lake Tahoe Hydrologic Unit. Owners of construction sites in this watershed must apply for the Lahontan Regional Water Board permit rather than the statewide Construction Stormwater General Permit. Construction sites within the Lahontan region must also comply with the Lahontan Region Project Guideline for Erosion Control (R6T-2016-0010).3

5. Construction activity that disturbs less than one acre of land surface, unless part of a larger common plan of development or the sale of one or more acres of disturbed land surface.

6. Construction activity covered by an individual NPDES Permit for stormwater discharges.

7. Construction activity that is subject to the Industrial Stormwater General Permit:
a. Landfill operations as described by Standard Industrial Classification (SIC) code 4953. Landfill operators typically enroll under the Construction Stormwater General Permit for initial construction and final closure of the landfill.
b. Concrete manufacturers of prefabricated products, ready-mix concrete, or slurries that are delivered to construction sites require enrollment in the Industrial Stormwater General Permit. Examples of this industrial activity are those facilities primarily engaged in manufacturing concrete building blocks and bricks, other concrete products not building blocks and bricks,

3 Lahontan Regional Water Quality Control Board, Order R6T-2016-0010 (March 10, 2016),
https://www.waterboards.ca.gov/lahontan/water_issues/programs/storm_water/docs/r6 t_2016_0010_cgp_combined.pdf> [as of May 20, 2021]

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or ready-mix concrete as categorized by Standard Industrial Classification (SIC) codes 3531, 3271, 3272, or 3273. Concrete manufacturing of prefabricated products, ready-mixed concrete, or slurries that are transported from construction sites where mixing occurs and delivered to a separate site require enrollment in the Industrial Stormwater General Permit.

8. Construction activity that discharges to combined sewer systems.

9. Discharges of stormwater identified in Clean Water Act § 402(l)(2), 33 USC § 1342(l)(2) (stormwater runoff from oil, gas, and mining operations) unless the discharge meets the conditions of 40 Code of Federal Regulations § 122.26(c)(1)(iii) as described in this General Permit.

10. Discharges of dredged or fill material to waters of the state. Those portions of the construction project that are located outside of waters of the state or waters of the United States are subject to this General Permit if the non-water portions disturb one or more acres of land.

II.C. Linear Underground and Overhead Projects Subject to this General Permit

1. Linear underground and overhead projects include, but are not limited to conveyance facilities, culverts, pipelines, or other linear corridors for:
a. The transportation of any gaseous, liquid, liquescent, and slurry material; b. Cable line or wire for the transmission of:
i. Electrical energy; or
ii. Communications, including internet, telephone, telegraph, radio, or television messages.
c. Ancillary facilities and substructures such as new access roads, helicopter landing zones, laydown yards, staging areas, substations, valve stations, etc. that primarily function as support for linear underground and overhead project construction activities.4

2. Construction support activities associated with linear underground and overhead projects include, but are not limited to:
a. Activities necessary for the installation of underground and overhead linear facilities (e.g., conduits, substructures, pipelines, towers, poles, cables, wires, connectors, switching, regulating and transforming equipment, vegetative management, and associated ancillary facilities); and

4 Regional Water Board staff may require, in writing, that the discharger obtain coverage through a traditional construction notice of intent when the construction of ancillary facilities more closely resembles traditional construction activities.

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b. Activities including underground utility mark-out, potholing, concrete and asphalt cutting and removal, trenching, excavating, boring and drilling, access road and pole/tower pad and cable/wire pull station, substructure installation, construction of tower footings and/or foundations, pole and tower installations, pipeline installations, welding, concrete and pavement repair or replacement, and stockpile/borrow locations.

II.D. Linear Underground and Overhead Projects Not Subject to this General Permit
This General Permit does not apply to the following linear underground and overhead project construction activity:

1. Routine maintenance projects. Routine maintenance projects are projects associated with operations and maintenance activities that are conducted on existing lines and facilities and within existing right-of-way, easements, franchise agreements, or other legally binding agreements of the discharger granting access to land. Routine maintenance projects include, but are not limited to projects that are conducted to:
a. Maintain the original purpose of the facility or hydraulic capacity; b. Update existing lines5 and facilities to comply with applicable codes, standards, and regulations regardless of if such projects result in increased capacity; and/or
c. Repair leaks.

2. Routine maintenance does not include construction of new lines or facilities resulting from compliance with applicable codes, standards, and regulations.

3. Routine maintenance projects do not include those areas of maintenance projects that are outside of an existing right-of-way, franchise, easements, or agreements. When a project must secure new areas, those areas may be subject to this General Permit based on the area of disturbed land outside the original right-of-way, easement, or agreement.

4. Linear underground and overhead project construction activity does not include field activities associated with the planning and design of a project (e.g., activities associated with route selection).

5. Tie-ins conducted immediately adjacent to “energized” or “pressurized” facilities by the discharger are not considered construction activities where all other linear underground and overhead project construction activities associated with the tie-in are covered by a Notice of Intent and SWPPP of a third party or municipal agency.

5 Update existing lines includes replacing existing lines with new materials or pipes.

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III. OBTAINING, REVISING, AND TERMINATING PERMIT COVERAGE III.A. Obtaining Permit Coverage for Traditional Construction Projects III.A.1. The Discharger shall obtain a Waste Discharge Identification (WDID) number prior to the commencement of construction activity by electronically certifying and submitting the following Permit Registration Documents through the State Water Board Stormwater Multiple Application and Report Tracking System (SMARTS)6:
a. Notice of Intent, including Risk Level determination as described in Attachment D.1;
b. Site Drawings and Maps;
c. Stormwater Pollution Prevention Plan (SWPPP) (see Section IV.O, below); d. Applicable plans, calculations, and other supporting documentation for compliance with existing permitted Phase I or Phase II municipal separate storm sewer system post-construction requirements or the post-construction standards of this General Permit;
e. Annual fee per the current 23 California Code of Regulations Chapter 9 fee schedule for NPDES stormwater permits; and
f. All applicable additional Permit Registration Document information as required in Attachment D.2 of this General Permit.

III.A.2. An applicant is considered to have General Permit regulatory coverage and can commence construction activity upon receipt of a WDID number generated by SMARTS. Dischargers shall post their site-specific WDID number in a site location that is viewable to the public or readily available upon request if unable to post publicly.

III.A.3. In the case of a public emergency that requires immediate construction activities involving one acre or more of land disturbance, a discharger shall submit a brief description of the emergency construction activity to the applicable Regional Water Board within five calendar days of the onset of site construction. The discharger shall then submit the required Permit Registration Documents through SMARTS within 30 calendar days of commencing site activity.

III.A.4. Failure to obtain General Permit coverage for stormwater and non-stormwater discharges covered by this General Permit to waters of the United States is a violation of the Clean Water Act and the California Water Code.

6 Dischargers are required to have a signed original Electronic Authorization Form on file with the State Water Board for each organization in SMARTS.

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III.B. Obtaining Permit Coverage for Linear Underground and Overhead Projects The discharger for a linear underground and overhead project shall designate a Legally Responsible Person for each of its WDIDs numbers. The discharger is responsible for enrollment under and compliance with this General Permit. The Legally Responsible Person, as defined in Attachment B of this General Permit, shall fulfill the electronic signature and certification requirements to obtain General Permit coverage (see Section VI.H, Electronic Signature and Certification Requirements.)
III.B.1. A discharger for a linear underground and overhead project shall obtain General Permit coverage under one or more applications submitted through SMARTS, per the requirements in Attachment E of this General Permit.

III.B.2. The Legally Responsible Person shall electronically certify and submit the following applicable Permit Registration Documents through SMARTS7 and obtain a WDID number prior to the commencement of any construction activities.
a. Notice of Intent, including linear underground and overhead project type determination as described in Attachment E.1;
b. Site-specific Stormwater Pollution Prevention Plan (SWPPP), Drawings, and Maps (see Section IV.O, below);
c. Annual fee per the current 23 California Code of Regulations Chapter 9 fee schedule for NPDES stormwater permits; and
d. All applicable additional Permit Registration Document information as required in Attachment E.2 of this General Permit.

III.B.3. Regulatory Coverage for linear underground and overhead project segments III.B.3.a. The discharger may separate a contiguous linear underground and overhead project into separately regulated segments. Linear underground and overhead project segments may consist of different risk types.

III.B.3.b. The discharger shall include a clear description in the Permit Registration Documents regarding how each segment relates to the overall linear underground and overhead project by identifying one or more of the following descriptions:
i. The segments are managed by separate contractors;
ii. The segments are constructed during distinct project phases; or iii. The segments are located in different topography, watersheds, or jurisdictional boundaries.

7 Dischargers are required to have a signed original Electronic Authorization Form on file with the State Water Board for each organization in SMARTS.

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III.B.3.c. Dischargers with corresponding linear underground and overhead project segments that cross Regional Water Board(s) boundaries (e.g., different segments of same project located within different Regional Water Board jurisdictions) must file separate Permit Registration Documents.

III.B.4. Programmatic Permitting Regulatory Coverage for linear underground and overhead projects
III.B.4.a. A discharger may submit one Notice of Intent requesting regional programmatic General Permit coverage for multiple non-contiguous linear underground and overhead projects, if the projects:
i. Are located within one Regional Water Board jurisdiction; ii. Are a group of projects of similar scopes with common construction activities; and
iii. Have the same Legally Responsible Person.

III.B.4.b. Effective December 17, 2022, a discharger deploying Executive Order N-73-20, per the requirements and due dates of the executive order, or amendments therein, may submit one Notice of Intent requesting statewide programmatic General Permit coverage for multiple non-contiguous linear underground and overhead broadband projects, where the installation of the utilities is outside of a construction project that is otherwise regulated under this General Permit.

III.B.4.b.i. A discharger deploying Executive Order N-73-20 may apply for a statewide programmatic permit for regulatory coverage under Order 2009-0009-DWQ (as amended by Orders 2010-0014-DWQ and 2012-0006-DWQ), from December 17, 2022 until September 1, 2023, by submitting the information required by Attachment E.2.

III.B.4.c. Linear underground and overhead project dischargers with programmatic permitting coverage shall submit, prior to the commencement of any construction activities for each non-contiguous site, a:
i. Common SWPPP with the Notice of Intent covering all the activities common to the projects; and
ii. Linear Construction Activity Notification for each site describing site- specific information in accordance with Attachment E.2, Section II.A.2.

III.B.5. An applicant is considered to have General Permit regulatory coverage and may commence construction activity upon receipt of a WDID number generated by SMARTS Dischargers shall post the project-specific WDID number in a site location that is visible to the public or readily available upon request if unable to post publicly.

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III.C. Regulatory Coverage under the Previous Permit
III.C.1. Dischargers that obtain coverage under State Water Board Order 2009-0009-DWQ, as amended by Orders 2010-0014-DWQ and 2012-0006-DWQ, (previous permit) prior to the effective date of this permit, may continue coverage under the previous permit until its regulated project(s) receive an approved Notice of Termination from the Regional Water Board, up to two years after the effective date of this General Permit. Two years after September 1, 2023, all existing Notices of Intent subject to the previous permit will be administratively terminated.

III.C.1.a. A discharger continuing regulatory coverage under the previous permit cannot increase a project’s disturbed acreage through the Change of Information process, on or after the effective date of this General Permit; the discharger must submit a Notice of Intent for coverage under this General Permit for the increase in disturbed acreage.

III.C.2. Dischargers with the previous permit’s Small Construction Rainfall Erosivity waiver may continue to operate under a project’s active waiver until it expires.

Waivers granted under the previous permit cannot be modified or extended.

III.C.3. Dischargers that submit a Notice of Termination for previous permit termination up to two years after the effective date of this General Permit and receive Notice of Termination approval from the Regional Water Board are not subject to this General Permit (unless the discharger subsequently submits new Permit Registration Documents).

III.C.4. Dischargers with coverage under the previous permit that need regulatory coverage after September 1, 2025 under this General Permit, shall submit, in SMARTS, the following items by August 31, 2025:
a. A certification of the discharger’s intent to obtain regulatory coverage under this General Permit;
b. A revised Notice of Intent and other Permit Registration Documents, revised to address new or changed requirements per this General Permit, as applicable; and
c. The applicable fee.

III.D. Small Construction Rainfall Erosivity Waiver
III.D.1. Dischargers are eligible for the Small Construction Rainfall Erosivity waiver (waiver) if:
a. The site is between one and five acres; and
b. The construction activity will take place during a period when the calculated rainfall erosivity factor is less than five.

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III.D.2. Dischargers with small sites that are part of a larger common plan of development, or dischargers that have programmatic permit coverage, do not qualify for a waiver unless the entire project qualifies for a waiver.

III.D.3. To request a waiver, the Legally Responsible Person shall submit a waiver application through SMARTS, and pay the appropriate fee to the State Water Board. If approved by the State Water Board, SMARTS will electronically provide the discharger with the waiver and a unique waiver identification number. The waiver is effective on the date the waiver identification number is issued and valid between the construction start and end dates, as entered in the waiver application.

III.D.4. A discharger qualifying for a waiver shall obtain a waiver identification number prior to starting any construction activities regulated by this General Permit.

III.D.5. A waiver is valid only if the correct start and end dates of construction activities are entered (and updated if necessary) through the Change of Information process in SMARTS.

III.D.6. The discharger may revise an original construction start date though the Change of Information process in SMARTS and shall provide documentation demonstrating the project had not started on the date originally submitted through SMARTS.

III.D.7. The discharger shall update the project end date through the Change of Information process in SMARTS prior to expiration of the waiver if the project completion date is anticipated to extend past the waiver expiration date. If the updated project end date results in a rainfall erosivity factor of five or greater, the discharger shall obtain coverage under this General Permit. If the discharger fails to update the project end date prior to expiration of waiver, they shall immediately obtain coverage under this General Permit.

III.D.8 The discharger shall post the unique waiver identification number in a site location that is visible to the public or readily available upon request if unable to post publicly.

III.D.9. A waiver does not provide General Permit coverage. Dischargers with a waiver are not required to comply with post-construction, sampling, monitoring, or other SWPPP requirements in this General Permit.

III.D.10. Regional Water Board staff may terminate a waiver if the Regional Water Board staff determines the discharge of stormwater runoff causes or contributes to an exceedance of a water quality standard or violates a prohibition in an applicable regional or statewide water quality control plan. The Regional Water Board Executive Officer or their delegate may require the discharger to obtain regulatory coverage under this General Permit or an NPDES permit issued by the Regional Water Board.

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III.E. Notice of Non-Applicability
III.E.1. A discharger claiming “No Discharge” through a Notice of Non-applicability (NONA) as set forth in Water Code § 13399.30 shall meet the following eligibility requirement:
a. The site’s physical location is not hydrologically connected to waters of the United States.

III.E.2. When claiming the “No Discharge” option, the discharger shall submit and certify via SMARTS both the NONA and a No Discharge Technical Report. The No Discharge Technical Report shall identify the site by address or parcel number and demonstrate that the site meets the eligibility requirement described above in Section III.E.1.a.

III.E.3. The No Discharge Technical Report shall be signed (wet signature and license number) by a California licensed professional engineer or geologist with hydrological expertise.

III.E.4. The Regional Water Board may require the No Discharge Technical Report to be reassessed if it determines that there are errors in the No Discharge Technical Report or if the site is hydrologically connected to waters of the United States.

III.F. Revising Permit Coverage Information
The discharger shall revise permit coverage information, as appropriate, to:

III.F.1. Update Construction Start and End Dates
III.F.1.a. The discharger shall electronically certify and submit a revised Notice of Intent through a Change of Information in SMARTS, when the construction start or end date changes, recalculating sediment risk and revising the SWPPP as appropriate. The Change of Information shall be submitted at least 14 days prior to the date that was modified, unless infeasible due to unforeseen circumstances.

III.F.1.b. If the discharger is revising the construction start date to a later date than previously submitted, the Change of Information shall contain time-stamped photo documentation depicting that construction activities have not commenced for the entirety of the site.

III.F.2. Reduce Acreage
III.F.2.a. When a portion of the site meets conditions for termination of coverage (Section III.H) or is sold/transferred to a new owner, the discharger may reduce the disturbed acreage covered under the General Permit. The discharger reducing disturbed acreage shall electronically certify and submit the following Permit Registration Document revisions in SMARTS, through a Change of Information, within 30 days of the reduction in acreage:
i. A revised Notice of Intent indicating the new site size;

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ii. Photos demonstrating final stabilization, if applicable; iii. Revised site map(s) showing (as applicable) acreage currently under construction; acreage sold/transferred, and/or added; and acreage currently stabilized in accordance with the Conditions for Termination of Coverage in Section III.H below; and
iv. A revised SWPPP to match the change in acreage.

III.F.2.b. For a larger common plan of development for residential use, the discharger may, through the Change of Information process, remove residential lots from permit coverage once the lot meets the following criteria:
i. The residential lot has been sold to the individual homeowner(s) for residential use;
ii. A certificate of occupancy or equivalent document, is maintained on-site and can be made available during inspections;
iii. The lot is less than one acre of disturbance;
iv. All construction activity conducted on the lot by the discharger is complete; and
v. The discharger has temporarily stabilized any unfinished yard and landscaping areas with BMPs.

III.F.2.c. The discharger shall upload, as an attachment in SMARTS, documentation of a contract (e.g., Covenants, Conditions, and Restrictions) requiring the individual homeowner to stabilize the yard and landscaping within one year and to maintain the temporary BMPs until the yard and landscaping are stabilized.

III.F.2.d. The discharger shall maintain General Permit coverage for any site, parcel, or individual lot that has not received Change of Information or Notice of Termination approval from the Regional Water Board or obtained coverage under the new owner’s Notice of Intent.

III.F.3. Termination of Programmatic Permit Coverage for Linear Underground and Overhead Projects
III.F.3.a. Upon completion of construction activities for a specific site with linear underground and overhead project programmatic permit coverage, the discharger shall submit a Linear Construction Termination Notification for each completed linear segment.

III.F.3.b. The site must meet the termination conditions in Section III.H.3 below.

III.F.3.c. The Linear Construction Termination Notification must include photos demonstrating final stabilization.

III.F.3.d. Regional Water Board approval of the Linear Construction Termination Notification terminates coverage for the specific site.

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III.F.4. Increase Acreage
III.F.4.a. If the disturbed acreage of the site will increase, the discharger shall certify and submit the following Permit Registration Documents revisions in SMARTS, through a Change of Information, prior to the increase in disturbed acreage:
i. A revised Notice of Intent indicating the new site size; ii. A revised site map(s) showing (as applicable) acreage currently under construction; acreage sold, transferred, and/or added; and acreage currently stabilized in accordance with the conditions for terminating coverage in Section III.H below; and
iii. A revised SWPPP to match current site size.

III.F.4.b. The discharger shall submit the applicable fees, in accordance with the revised fee notification, within 14 calendar days of the notification date. The Change of Information will be returned if these fees are not received by the State Water Board within 14 calendar days of the notification date.

III.F.4.c. Regulatory coverage under this General Permit for the added acreage is not approved until the Regional Water Board approves the Change of Information.

III.F.4.d. If the increased acreage is greater than one-fourth mile from the existing site boundary and is an acre or larger, the discharger is required to submit a separate Notice of Intent.

III.F.5. Change in Ownership
III.F.5.a. Prior to a sale/transfer of a site, parcel, or individual lot (change of ownership), the existing discharger shall submit a Notice of Termination for change of ownership and a certification that the new owner has been notified of applicable requirements to obtain new General Permit for the qualifying activities. The existing discharger certification shall include the name, address, telephone number, and email address of the proposed new owner in the Notice of Termination submitted through SMARTS.8
III.F.5.b. General Permit coverage is not transferable to a new owner. The new discharger will need to submit their own Permit Registration Documents to obtain a new WDID number prior to continuing construction activities and/or installing final landscaping (including meeting conditions for termination of coverage). The new discharger shall enter the original project start date (initial date of disturbance) from the previous discharger(s).

8 Dischargers that are submitting a Notice of Termination for a change of ownership, where the new owner will obtain permit coverage to complete construction, are not required to comply with the requirements in Order Section III.H.

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III.G. Inactive Projects
III.G.1. Dischargers with projects where all construction activities (including passive treatment, active treatment systems, and/or active equipment) will be suspended for 30 days or more may submit a Change of Information through SMARTS to revise the SWPPP. The Change of Information shall include:
a. Revised site map depicting the current status of construction; and b. Photographs showing the temporary stabilization BMPs that were implemented.

III.G.2. Upon Regional Water Board approval of the Change of Information, sampling may be suspended, and monitoring and inspections may be reduced as follows:

III.G.2.a. A QSD shall visit the inactive project within 14 days of Regional Water Board approval of the Change of Information to verify that the SWPPP is being implemented accordingly. If necessary, the QSD shall amend the SWPPP to address all new conditions not previously considered through a Change of Information in SMARTS.

III.G.2.b. A QSP or trained delegate shall visually inspect the inactive project at least once every calendar month and prior to any weather pattern that is forecasted to have a 50 percent or greater chance of 0.5 inches or more in a 24-hour period. Please refer to Attachments D and E Section III.C for information pertaining to visual inspection requirements.
i. The QSP or trained delegate shall verify BMPs are functioning in accordance with the SWPPP and implement corrective actions where necessary.

III.G.2.c. The above inspections are not required during dangerous weather conditions or when access to the site is infeasible (e.g., due to snow accumulation) or unsafe.

III.G.3. Dischargers wishing to resume construction activities or the use of passive treatment, active treatment systems, and/or active equipment shall submit a Change of Information through SMARTS requesting to resume the project along with a revised site map based on current site conditions. Upon Regional Water Board approval of the Change of Information, the discharger is required to comply with all applicable requirements of this General Permit to resume construction activities at the site.

III.H. Terminating Permit Coverage
III.H.1. To terminate General Permit coverage, the discharger shall electronically certify and submit the required documentation (Section III.H.2 below) to demonstrate compliance with all General Permit coverage termination requirements, including applicable post-construction BMPs and/or low impact development features.

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III.H.2. The discharger shall electronically certify and submit the following through SMARTS to be considered for General Permit coverage termination:
a. A complete Notice of Termination;
b. QSP-prepared final Notice of Termination inspection with the QSP name and valid QSP certificate number;
c. A final site map; and
d. Photos demonstrating final stabilization and the implementation of applicable post-construction BMPs and/or low impact development.

III.H.3. The discharger shall certify and submit a final site map, as part of the Notice of Termination documents through SMARTS. The Notice of Termination final site map shall, at minimum, include the following:
a. Project boundaries and adjacent lands with labeled key features, such as roadways and waterbodies;
b. Developed drainage basin boundaries and discharge location points; c. Site entrances and exits, lot boundaries, roads, structures, and features related to the project that may be used as a reference; d. Specific permanent erosion control BMPs, post-construction BMPs, and low impact development features;
e. Individual erosion control BMPs (including final landscaping) identified using hatch patterns, symbols, or shading unique to each BMP; f. Location and orientation of all photos used to document final site conditions and demonstrate compliance with post-construction requirements of this General Permit; and
g. If applicable, areas of the site being transferred to new ownership, and the name and contact information of the owner.

III.H.4. The Regional Water Board will consider a site, parcel, or individual lot complete only when all portions of the site comply with all the following conditions:
a. The discharger has completed all construction activity; b. There is no greater potential for construction-related stormwater pollutants to be discharged into site runoff than prior to the construction activity; c. Construction-related equipment and temporary BMPs have been removed from the site, except as set forth in Section III.F.2.b above; d. Construction materials and wastes have been disposed of properly; e. Soils disturbed by construction activities have been permanently stabilized (final stabilization), except as set forth in Section III.F.2.b above, using materials that:

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i. Have a product life that support the full and continued stabilization of the site;
ii. Achieve stabilization without becoming trash or debris; and iii. Minimize the risk of wildlife entrapment;
f. The discharger has ensured the QSP completed on-site visual inspections and verified the site complies with all Notice of Termination requirements, including installation of post-construction stormwater runoff BMPs and/or low impact development features;
g. The Legally Responsible Person has submitted the information in the Notice of Termination and has certified and submitted through SMARTS; and h. The discharger has demonstrated that the site complies with all Notice of Termination conditions above (Section III.H) and all final stabilization conditions by one of the following methods:
i. 70 percent final cover method. No computational proof required.

Requires permanent vegetative cover to be evenly established over 70 percent of all disturbed and exposed areas of soil (non-paved or non-built). In areas that naturally have low vegetative coverage (e.g., deserts), 70 percent of natural conditions of local undisturbed areas is acceptable. Photos of all site areas are required to verify compliance with the 70 percent final cover requirement;
OR
ii. Revised Universal Soil Loss Equation (RUSLE or RUSLE2) method. Computational proof required. Site conditions shall match values used in method computation. Photos of all site areas are required to verify pre-construction and post-construction conditions used in the computations;
OR
iii. Custom method. The discharger may request approval from the Regional Water Board to use a method or analytical model other than Section III.H.4.h.i and 4.h.ii above to demonstrate that the site complies with the “final stabilization” requirements. Photos of all site areas are required to verify the custom method used.

III.H.5. The Notice of Termination photo documentation for General Permit compliance verification shall include photos of the site’s final site conditions; post- construction BMPs and/or low impact development features; a description of the corresponding location, and orientation of photos as indicated on the final site map.

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III.H.6. The Notice of Termination shall include a long-term maintenance plan9 for the post-construction stormwater runoff BMPs and/or low impact development features being implemented.

III.H.7. The Notice of Termination will be automatically approved 30 calendar days after the date of Notice of Termination is submitted, unless, within the 30 calendar days the Regional Water Board notifies the discharger through SMARTS that the Notice of Termination has been denied, returned, or accepted for review.

III.H.8. All General Permit requirements remain in effect until the Notice of Termination is approved. The Legally Responsible Person will be notified through SMARTS communication when the discharger’s General Permit coverage and corresponding WDID number are terminated.

IV. PERMIT REQUIREMENTS
IV.A. Authorized Non-Stormwater Discharges
IV.A.1. Non-stormwater discharges from the following de-chlorinated potable and non- potable water sources are authorized if they comply with the requirements in Section IV.A.2 of this General Permit:
a. Fire-fighting activity;
b. Fire hydrant system flushing;
c. Irrigation of vegetative erosion control measures;
d. De-chlorinated potable water, including uncontaminated water line flushing; e. Hydrostatic pipe flushing and testing water;
f. Air conditioning or compressor condensate;
g. Uncontaminated groundwater or spring water from construction dewatering activities in compliance with Attachment J; and
h. Water to control dust.

IV.A.2. The above non-stormwater discharges are authorized under the following conditions:
a. The discharge is not routed through site areas with exposed soil, except for water used for dust control or to vegetation irrigation to stabilize areas; b. The discharge does not cause or contribute to an exceedance of water quality standards in the receiving water;

9 For the purposes of this requirement, a long-term maintenance plan shall be designed for a minimum of five years, and describe the responsible party(ies), schedule, and procedures needed to ensure that post-construction features are adequately maintained and functional.

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c. The discharge complies with other applicable requirements of this General Permit including applicable action levels, effluent limitations, and monitoring and reporting requirements;
d. The discharge is not prohibited by an applicable regional or statewide water quality control plan;
e. The discharge is in accordance with other applicable State and Regional Water Board permits; and
f. The discharge does not contain toxic constituents in toxic amounts and does not cause toxicity in the receiving water body.

IV.B. Discharge Prohibitions
IV.B.1. Dischargers shall not violate any discharge prohibitions contained in applicable water quality control plans.

IV.B.2. Discharges to Areas of Special Biological Significance (ASBS) are prohibited by the California Ocean Plan, unless granted an exception issued by the State Water Board.

IV.B.3. All discharges are prohibited except for the stormwater and non-stormwater discharges specifically authorized by this General Permit or another NPDES permit. The discharger shall notify the Regional Water Board of existing or anticipated non-stormwater discharges not authorized by this General Permit, within 24 hours of the discharge, to determine if regulatory coverage is necessary through a separate NPDES permit.

IV.B.4. All of the following discharges are prohibited:
a. Debris and trash, in accordance with State Water Board Resolution 2015-0019, the Trash Provisions of the Water Quality Control Plan for Ocean Waters of California and the Water Quality Control Plan for Inland Surface Waters, Enclosed Bays, and Estuaries of California, as applicable to construction stormwater discharges.
i. To comply with the Trash Provisions, dischargers shall implement, operate, and maintain trash management, treatment, and institutional controls to eliminate debris and trash from all stormwater discharges and authorized non-stormwater dischargers consistent with the prohibition of the discharge of debris and trash regulated by this General Permit. If the discharger is unable to comply with the prohibition of the discharge of debris and trash, the discharger must submit, for Regional Water Board Executive Office or designee approval, an amended Stormwater Pollution Prevention Plan addressing:

1. A demonstration that the discharger is unable to comply with this outright prohibition of the discharge of debris and trash; and

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2. A demonstration that the discharger’s chosen combination of trash management, treatment, and institutional controls achieves full capture system equivalency.
b. Treatment chemicals except as authorized in Attachment F and G; c. Wastewater from washout or cleanout of areas, structures or equipment with concrete, grout, stucco, paint or other construction materials; d. Form-release oils and curing compounds;
e. Fuels, oils, fluids, or other materials used in vehicle and equipment operation and maintenance;
f. Soaps, solvents, or detergents (e.g., used in vehicle equipment washing or external building wash down); and
g. Toxic or hazardous substances (e.g., asbestos, lead, mercury, or PCBs).

IV.C. Effluent Limitations and Action Levels
IV.C.1. Narrative Effluent Limitations
IV.C.1.a. Stormwater discharges and authorized non-stormwater discharges regulated by this General Permit shall not contain a hazardous substance equal to or in excess of reportable quantities established in 40 Code of Federal Regulations §§ 117.3 and 302.4, unless a separate NPDES Permit has been issued to regulate those discharges.

IV.C.1.b. Dischargers shall minimize or prevent pollutants in stormwater discharges and authorized non-stormwater discharges through the use of controls, structures, and management practices set forth in the order and attachments of this General Permit that achieve best available technology (BAT) for toxic and non-conventional pollutants and best conventional technology (BCT) for conventional pollutants.

IV.C.2. Numeric Effluent Limitations10
IV.C.2.a. All dischargers implementing active treatment systems are subject to the numeric effluent limitations required in Attachment F.

IV.C.2.b. All dischargers that are Responsible Dischargers for a TMDL with a waste load allocation that was translated into a TMDL-related numeric effluent limitation, are subject to the numeric effluent limitations as indicated by Table H-2 in Attachment H.

10 Refer to Attachment B of this General Permit for the definitions of numeric effluent limitations and numeric effluent limitation exceedances.

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IV.C.3. Numeric Action Levels11
IV.C.3.a. All dischargers that are Responsible Dischargers for a TMDL with a waste load allocation that was translated into a TMDL-related numeric action level, are subject to the numeric action level as indicated by Table H-2 in Attachment H.

IV.C.3.b. Dischargers with dewatering activities not subject to a separate NPDES permit are subject to the numeric action levels required in Attachment J.

IV.C.3.c. For Risk Level 2 and 3 sites, refer to Attachment D, Section III.G. For Type 2 and 3 linear underground and overhead projects, refer to Attachment E, Section III.G. For stormwater and authorized non-stormwater discharges, the numeric action level for pH is provided as a range where the lower value is 6.5 pH standard units and the upper value is 8.5 pH standard units. The discharger shall report the field reading to two decimal places. A numeric action level exceedance for pH occurs when the reading, obtained per each discharge location per day of each qualifying precipitation event, is below the lower value or above the upper value, as shown in Table 1 of this Section.

IV.C.3.d. Risk Level 2 and 3 sites, refer to Attachment D, Section III.G. For Type 2 and 3 linear underground and overhead projects, refer to Attachment E, Section III.G. For stormwater and authorized non-stormwater discharges the numeric action level for turbidity is 250 Nephelometric Turbidity Units (NTU). An exceedance of the turbidity numeric action level occurs when the field reading, obtained per each discharge location per day of each qualifying event, is over 250 NTU, as shown in Table 1 of this Section.

11 Refer to Attachment B of this General permit for the definitions of numeric action levels and numeric action level exceedances.

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Table 1. Numeric Action Levels, Test Methods, Detection Limits, and Reporting Units
Parameter Test Method Discharger
Type
Method
Detection
Limit
Units
Numeric
Action
Level
TMDL-
Related
Pollutant
U.S. EPA-approved
test method for
specific pollutant
parameter
Responsible
Dischargers
Depends
on the test
method
mg/L
Refer to
Table H-2 in
Attachment
H
pH
Field test with
calibrated portable
instrument using
EPA approved
procedures
Risk Level 2
and 3

Risk Type 2
and 3

0.2 pH
Units
Lower
Value= 6.5

Upper
Value= 8.5
Turbidity
EPA 0180.1 and/or
field test with
calibrated portable
instrument
Risk Level 2
and 3

Risk Type 2
and 3
1 NTU 250
IV.D. Receiving Water Limitations
IV.D.1. The discharger shall ensure that stormwater discharges and authorized non- stormwater discharges to any surface or ground water will not adversely affect human health or the environment.

IV.D.2. The discharger shall ensure that stormwater discharges and authorized non- stormwater discharges will not contain pollutants in quantities that threaten to cause pollution or a public nuisance.

IV.D.3. The discharger shall ensure that stormwater discharges and authorized non- stormwater discharges will not contain pollutants that cause or contribute to an exceedance of any applicable water quality objectives or water quality standards contained in an applicable water quality control plan.

IV.D.4. Responsible Dischargers shall comply with the applicable TMDL implementation requirements in Attachment H of this General Permit, including TMDL-specific additional BMPs and site pollutant modeling, numeric action levels, and/or numeric effluent limitations.

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IV.E. Linear Underground and Overhead Project Requirements Dischargers with linear underground and/or overhead projects shall comply with the requirements included in Attachments E, E.1, and E.2 of this General Permit.

IV.F. Risk Level 1 Requirements
Risk Level 1 dischargers shall comply with the requirements included in Attachment D, D.1, and D.2 of this General Permit.

IV.G. Risk Level 2 Requirements
Risk Level 2 dischargers shall comply with the requirements included in Attachment D, D.1, and D.2 of this General Permit.

IV.H. Risk Level 3 Requirements
Risk Level 3 dischargers shall comply with the requirements included in Attachment D, D.1, and D.2 of this General Permit.

IV.I. Active Treatment System Requirements
Dischargers implementing an active treatment system shall comply with all of the requirements in Attachment F of this General Permit.

IV.J. Passive Treatment Requirements
Dischargers implementing passive treatment on-site shall comply with all the requirements in Attachment G of this General Permit.

IV.K. Total Maximum Daily Load Implementation Requirements IV.K.1. Responsible Dischargers are dischargers who:
a. Discharge stormwater and authorized non-stormwater directly, or through a municipal separate sewer system or other conveyance, to impaired water bodies or watersheds identified in a U.S. EPA approved total maximum daily load (TMDL) with a waste load allocation assigned to construction stormwater sources; and
b. Have one or more TMDL-specific pollutant sources present on-site with the potential to enter construction stormwater discharge, which are required to be identified in the pollutant source assessment (refer to Section IV.O.2.i below).

IV.K.2. Responsible Dischargers shall comply with the applicable requirements in Attachment H of this General Permit.

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IV.L. Discharges Subject to the California Ocean Plan
IV.L.1. Discharges to Ocean Waters
IV.L.1.a. Dischargers that discharge directly into ocean waters that are subject to the model monitoring provisions of the California Ocean Plan shall be deemed in compliance with applicable California Ocean Plan model monitoring provisions when in compliance with monitoring requirements of this General Permit.

IV.L.1.b. The Regional Water Boards may require a discharger that discharges directly into ocean waters who has demonstrated non-compliance with this General Permit’s monitoring requirements to develop and implement a monitoring plan in compliance with additional effluent and ocean monitoring provisions established pursuant to Water Code § 13383.

IV.L.2. Discharges Granted an Exception for Areas of Special Biological Significance (ASBS)
IV.L.2.a. Dischargers who were granted an exception to the California Ocean Plan prohibition of discharges of waste directly to an ASBS pursuant to Resolution 2012-0012 amended by Resolution 2012-0031 shall comply with the conditions and requirements set forth in Attachment I of this General Permit. Any discharger that applies for and is granted an exception to the California Ocean Plan prohibition after September 1, 2013, shall comply with the conditions and requirements set forth in the granted exception.

IV.M. Dewatering Requirements
IV.M.1. Dischargers with dewatering activities subject to a separate NPDES permit (e.g., de minimis and low threat discharges) are not subject to comply with the dewatering requirements of this General Permit as found in Attachment J and shall obtain coverage as required by the State or Regional Water Boards.

IV.M.2. Dischargers with dewatering activities not subject to a separate NPDES permit (e.g., de minimis and low threat discharges) shall comply with the dewatering requirements in Attachment J.

IV.N. Post-Construction Requirements
IV.N.1. All dischargers, other than linear underground and overhead project dischargers, shall implement BMPs to reduce runoff and pollutants in stormwater discharges that are reasonably foreseeable after all construction phases have been completed at the site (post-construction BMPs).

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IV.N.2. Dischargers subject to the post-construction requirements of an existing NPDES Phase I or Phase II municipal separate storm sewer system permit are not subject to the post-construction requirements in Section IV.N.3 below, and shall submit the following items with their Permit Registration Documents through SMARTS:
a. An attachment or web-source containing the applicable NPDES Phase I or Phase II municipal separate storm sewer system permittee’s post- construction requirements; and
b. The post-construction plans and calculations submitted to, or approved by, the applicable NPDES Phase I or Phase II municipal separate storm sewer system permittee. If the discharger submitted preliminary post-construction plans and calculations as a Permit Registration Document, the discharger shall submit the approved plans and calculations within 14 days of approval by the municipal stormwater permittee, through a Change of Information in SMARTS. The discharger shall submit a Change of Information in SMARTS for any revisions to post-construction plans and calculations prior to submitting the Notice of Termination.

IV.N.3. All dischargers, other than linear underground and overhead project dischargers or dischargers subject to the post-construction requirements of an existing NPDES Phase I or Phase II municipal separate storm sewer system permit, shall comply with the following post-construction runoff reduction requirements.

The discharger shall comply with this General Permit’s post-construction requirements if the Permit Registration Documents were submitted prior to the effective date of applicable post-construction requirements of the corresponding NPDES Phase I or Phase II municipal stormwater permit.

IV.N.4. The discharger shall use non-structural and/or structural measures to replicate the pre-construction water balance (for this General Permit, defined as the volume of rainfall that ends up as runoff) for the smallest storms up to and including the 85th percentile, 24-hour precipitation event (or the smallest precipitation event that generates runoff, whichever is larger).

IV.N.5. For sites with disturbed area exceeding two acres, the discharger shall preserve the pre-construction drainage density (miles of stream length per square mile of drainage area) for all drainage areas within the area serving a first order stream12 or larger stream and ensure that post-project runoff time of concentration is equal to or greater than pre-project time of concentration.

IV.N.6. The discharger shall certify and submit post-construction plans, calculations, and other supporting documentation as a Permit Registration Document in SMARTS. The discharger shall submit a Change of Information in SMARTS for

12 A first order stream is defined as a stream with no tributaries.

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any revisions to post-construction plans and calculations prior to submitting the Notice of Termination.

IV.N.7. Regional Water Board staff may review post-construction plans, calculations, and other supporting documentation to verify that the post-construction water balance is accurate; and may request that the discharger make revisions if necessary.

IV.N.8. The discharger may use the contact information found online or in Attachment C to request Regional Water Board staff review post-construction plans, calculations, and other supporting documentation prior to and during construction.

IV.O. Stormwater Pollution Prevention Plan Requirements IV.O.1. The discharger shall ensure the site’s SWPPP complies with the below conditions:
a. A site-specific SWPPP is developed, and amended as necessary, by a QSD. The discharger is responsible for keeping the SWPPP and associated documents updated in SMARTS to reflect current site conditions and construction activities.
b. Trained personnel and BMP materials are available at the site as required by this General Permit.
c. The SWPPP includes the implementation of BMPs that comply with BAT, BCT, and ensure compliance with water quality standards; additional BMPs based on input from the QSP to address numeric action level and numeric effluent limitation exceedances; and additional training needed for the QSP, Legally Responsible Person, or designated persons on-site. d. The SWPPP is available at the site and made available upon request by a federal, State, or municipal inspector. A current copy of the site-specific SWPPP and any site inspection reports required by this General Permit may be kept in electronic format at the site so long as the information requested by a federal, State, or municipal inspector can be made available during an inspection. All maps are legible and available in hard copy at the site.

IV.O.2. The SWPPP shall include:
a. Identification of all pollutants, their sources, and control mechanisms, including sources of sediment associated with all construction activities (e.g., sediment, paint, cement, stucco, cleaners, site erosion);

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b. Pollutant source assessments, including a list of potential pollutant sources and identification of site areas where additional BMPs are necessary to reduce or prevent pollutants in stormwater and authorized non-stormwater discharges, per the following minimum requirements when developing the pollutant source assessment:
i. Consider all potential sources of pollutants, including non-visible pollutants which are known, or should be known to occur on-site including those that:

1. Are used in construction activities;

2. Are stored on-site;

3. Were spilled or released during construction activities or past land use activities and not cleaned up; and

4. Were applied to land as part of past land use activities. ii. Consider all potential sources of pollutants associated with applicable TMDLs listed in Attachment H, and state whether or not sources of those pollutants are present on-site;
iii. Consider the quantity, physical characteristics (e.g., liquid, powder, solid), and locations of each potential pollutant exposed, source handled, produced, stored, recycled, or disposed of on-site; iv. Consider the degree to which pollutants associated with those materials may be exposed to and mobilized by contact with stormwater; and v. Consider the direct and indirect pathways that pollutants may be exposed to stormwater or authorized non-stormwater discharges. This shall include an assessment of past spills or leaks, non-stormwater discharges, and discharges from adjoining areas.
c. Description of site-specific BMPs implemented to reduce or eliminate stormwater pollution, including the following, if applicable:
i. Minimum sediment and erosion control BMPs as outlined in Attachments D and E of this General Permit;
ii. Active treatment systems as included in an Active Treatment System Plan (as required in Section E.1 of Attachment F);
iii. Passive treatment technologies as included in a Passive Treatment Plan (as required in Section D.2 of Attachment G);
iv. BMPs implemented to address applicable TMDL implementation requirements (as required by Attachment H); and
v. Dewatering systems (as required by Attachment J).

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d. Site-specific BMPs initialized immediately to temporarily stabilize an area disturbed by construction where construction activities will not be resumed within 14 days;
e. Identification, elimination, control, or treatment information for all non- stormwater discharges from the site not regulated by this or another NPDES permit;
f. Description of efforts and BMPs used to minimize and control pollutants discharged from equipment and vehicle washing, wheel wash water, and other wash waters. Wash waters must be captured and properly disposed of and/or treated to mitigate impacts to water quality;
g. Description of efforts and BMPs used to minimize exposure of building materials, building products, construction wastes, trash, landscape materials, fertilizers, pesticides, herbicides, detergents, sanitary waste, and other materials present on the site to precipitation and to stormwater; h. Description of spill and leak prevention and response plan including:
i. Procedures that effectively address hazardous and non-hazardous spills in accordance with law;
ii. Spill and leak response equipment and materials to be available on-site, cleaned up immediately, and disposed of properly; and
iii. Personnel are assigned and trained for spill and leak prevention and response.
i. Construction Site Monitoring Program that describes methods and procedures for monitoring discharges in accordance with the applicable Attachment D or E that includes the following:
i. Visual inspection locations, inspection procedures, and follow-up tracking procedures.
ii. Applicable sampling locations, collection, and handling procedures shall include detailed procedures for field analysis, sample collection, storage, preservation, and shipping to the laboratory to ensure consistent quality assurance and control is maintained. iii. A copy of the Chain of Custody form used when handling and shipping samples.
iv. Identification of the analytical methods and related method detection limits (if applicable) for each parameter.
v. Watershed Monitoring Option:

1. If the discharger is part of a qualified regional watershed-based monitoring program approved by the Regional Water Board Executive Officer or their delegate, the discharger may be eligible for relief from the monitoring requirements in the applicable

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Attachment D or E. The Regional Water Board may approve proposals to substitute a qualified watershed-based monitoring program if it determines the program will provide information to determine each discharger’s compliance with the requirements of this General Permit.
j. Title Sheet(s) with:
i. Project name;
ii. Project location (vicinity map);
iii. Preliminary schedule of activities;
iv. Site operating hours (hours when construction activities are occurring); v. Index of attachments;
vi. Contact information for QSD(s), QSP(s), and trained delegates (name, phone numbers, license or certification number); and
vii. Signature of the QSD(s) who prepared the SWPPP.
k. Pre-Earthwork Drawing with:
i. Site and project boundaries;
ii. Areas disturbed during geotechnical or other preconstruction investigation work;
iii. Existing roads and trails;
iv. Drainage areas;
v. Discharge locations;
vi. Existing storm drain system if applicable; and
vii. Proposed locations of storage areas for waste, construction materials, project staging areas, stockpiles, vehicles, equipment and vehicle maintenance, loading/unloading of materials, site access (entrance/exits), fueling, water storage, water transfer for dust control, demolition, and areas of other construction support activities. l. Construction and Earthwork Drawing(s) with:
i. Site layout (grading plans) including roads;
ii. Site and project boundaries;
iii. Drainage areas;
iv. Discharge locations;
v. Sampling locations;
vi. Areas of soil disturbance (temporary or permanent); vii. Proposed active areas of soil disturbance (cut or fill);

Carlsbad City CouncilOctober 21, 2025

Carlsbad City Council
October 21, 2025