City Council Agenda November 7, 2023
Test - Boring No. J
delta H 1.25 inches First Reading 3.60 ft User Input
delta T 60 minutes Last Reading 3.71 ft Calculated Values effective radius 3 inches Hole Depth 5.17 ft
H start 18.75 inches Riser Height 0
H end 17.50 inches
H ave 18.125 inches
I
t 0.10 inches/hour
"Porchet Method"
Source: Riverside County Low Impact Development BMP Design Handbook, 2011 0751-0005_PorchetMethod_InfiltrationRate_PercTest Page 908 of 1329 Page 11 of 13 City Council Agenda November 7, 2023 Infiltration Test Field Measurements
2930 Union Road
BORING NO. K
Site Location: Paso Robles, CA F-103116
Auger Diameter: 6”
Depth: 56 inches
Date: September 29, 2022
Time (Minutes) Depth (inches) Change in Depth (Inches) Rate (Inches/Hour) ---- 28.50 ---- ----
30 minutes 31.25 2.75 5.50
30 minutes 34.25 3.00 6.00
30 minutes 37.25 3.00 6.00
30 minutes 39.25 2.00 4.00
30 minutes 41.50 2.25 4.50
30 minutes 43.00 1.50 3.00
30 minutes 44.75 1.75 3.50
30 minutes 46.25 1.50 3.00
Range used
for Porchet
conversion
City Council Agenda November 7, 2023
Test - Boring No. K
delta H 3.25 inches First Reading 3.58 ft User Input
delta T 90 minutes Last Reading 3.85 ft Calculated Values effective radius 3 inches Hole Depth 5.17 ft
H start 19.00 inches Riser Height 0
H end 15.75 inches
H ave 17.375 inches
I
t 0.17 inches/hour
"Porchet Method"
Source: Riverside County Low Impact Development BMP Design Handbook, 2011 0751-0005_PorchetMethod_InfiltrationRate_PercTest Page 910 of 1329 Page 12 of 13 City Council Agenda November 7, 2023 Infiltration Test Field Measurements
2930 Union Road
BORING NO. L
Site Location: Paso Robles, CA F-103116
Auger Diameter: 6”
Depth: 63 inches
Date: September 28, 2022
Time (Minutes) Depth (inches) Change in Depth (Inches) Rate (Inches/Hour) ---- 33.00 ---- ----
30 minutes 35.75 2.75 5.50
30 minutes 38.25 2.50 5.00
30 minutes 40.50 2.25 4.50
30 minutes 42.75 2.25 4.50
30 minutes 44.375 1.625 3.25
30 minutes 46.125 1.75 3.50
30 minutes 47.75 1.625 3.25
30 minutes 49.50 1.75 3.50
Range used
for Porchet
conversion
City Council Agenda November 7, 2023
Test - Boring No. L
delta H 3.375 inches First Reading 3.84 ft User Input
delta T 90 minutes Last Reading 4.13 ft Calculated Values effective radius 3 inches Hole Depth 5.25 ft
H start 16.88 inches Riser Height 0
H end 13.50 inches
H ave 15.1875 inches
I
t 0.20 inches/hour
"Porchet Method"
Source: Riverside County Low Impact Development BMP Design Handbook, 2011 0751-0005_PorchetMethod_InfiltrationRate_PercTest Page 912 of 1329 Page 13 of 13 City Council Agenda November 7, 2023
City Council Agenda November 7, 2023
United States
Department of
Agriculture
A product of the National
Cooperative Soil Survey,
a joint effort of the United
States Department of
Agriculture and other
Federal agencies, State
agencies including the
Agricultural Experiment
Stations, and local
participants
Custom Soil Resource
Report for
San Luis Obispo
County, California,
Paso Robles Area
Natural
Resources
Conservation
Service
October 17, 2022 Page 914 of 1329
City Council Agenda November 7, 2023
45 Custom Soil Resource Report
Map—Hydrologic Soil Group
3945400 3945600 3945800 3946000 3946200 3946400 3946600 3946800 3947000 3945400 3945600 3945800 3946000 3946200 3946400 3946600 3946800 3947000 712100 712300 712500 712700 712900 713100
712100 712300 712500 712700 712900 713100 713300
35° 38' 39'' N
120° 39' 31'' W
35° 38' 39'' N
120° 38' 38'' W
35° 37' 42'' N
120° 39' 31'' W
35° 37' 42'' N
120° 38' 38'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 10N WGS84 0 400 800 1600 2400
Feet
0 100 200 400 600
Meters
Map Scale: 1:8,620 if printed on A portrait (8.5" x 11") sheet.
Soil Map may not be valid at this scale.
City Council Agenda November 7, 2023
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Rating Polygons
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Lines
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Points
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as of the version date(s) listed below.
Soil Survey Area: San Luis Obispo County, California, Paso Robles Area
Survey Area Data: Version 16, Sep 14, 2022
Soil map units are labeled (as space allows) for map scales 1:50,000 or larger.
Date(s) aerial images were photographed: Mar 12, 2022—Apr 12, 2022
The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background Custom Soil Resource Report
46
City Council Agenda November 7, 2023
MAP LEGEND MAP INFORMATION
imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident.
Custom Soil Resource Report
47
City Council Agenda November 7, 2023
Table—Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 100 Arbuckle fine sandy
loam, 0 to 2 percent
slopes
C 22.6 5.9%
102 Arbuckle-Positas
complex, 9 to 15
percent slopes
C 4.2 1.1%
103 Arbuckle-Positas
complex, 15 to 30
percent slopes
C 39.1 10.1%
104 Arbuckle-Positas
complex, 30 to 50
percent slopes
C 14.3 3.7%
106 Arbuckle-San Ysidro
complex, 2 to 9
percent slopes
C 82.1 21.3%
133 Cropley clay, 2 to 9
percent slopes, MLRA
14 C 33.8 8.8%
149 Hanford and Greenfield
gravelly sandy loams,
0 to 2 percent slopes
A 12.5 3.2%
150 Hanford and Greenfield
gravelly sandy loams,
2 to 9 percent slopes
A 14.2 3.7%
167 Metz-Tujunga complex,
occasionally flooded, 0
to 5 percent slopes
A 3.5 0.9%
177 Nacimiento-Ayar
complex, 9 to 30
percent slopes
C 76.2 19.7%
179 Nacimiento-Los Osos
complex, 9 to 30
percent slopes
60.4 15.6%
197 San Ysidro loam, 0 to 2
percent slopes, MLRA
14 C 23.0 6.0%
300 Corducci and Typic
Xerofluvents, 0 to 5
percent slopes,
occasionally flooded,
MLRA 14
A 0.1 0.0%
Totals for Area of Interest 386.2 100.0%
Rating Options—Hydrologic Soil Group
Aggregation Method: Dominant Condition
Aggregation is the process by which a set of component attribute values is reduced to a single value that represents the map unit as a whole.
Custom Soil Resource Report
48
City Council Agenda November 7, 2023
A map unit is typically composed of one or more "components". A component is either some type of soil or some nonsoil entity, e.g., rock outcrop. For the attribute being aggregated, the first step of the aggregation process is to derive one attribute value for each of a map unit's components. From this set of component attributes, the next step of the aggregation process derives a single value that represents the map unit as a whole. Once a single value for each map unit is derived, a thematic map for soil map units can be rendered. Aggregation must be done because, on any soil map, map units are delineated but components are not.
For each of a map unit's components, a corresponding percent composition is recorded. A percent composition of 60 indicates that the corresponding component typically makes up approximately 60% of the map unit. Percent composition is a critical factor in some, but not all, aggregation methods.
The aggregation method "Dominant Condition" first groups like attribute values for the components in a map unit. For each group, percent composition is set to the sum of the percent composition of all components participating in that group. These groups now represent "conditions" rather than components. The attribute value associated with the group with the highest cumulative percent composition is returned. If more than one group shares the highest cumulative percent composition, the corresponding "tie-break" rule determines which value should be returned. The "tie-break" rule indicates whether the lower or higher group value should be returned in the case of a percent composition tie. The result returned by this aggregation method represents the dominant condition throughout the map unit only when no tie has occurred.
Component Percent Cutoff: None Specified
Components whose percent composition is below the cutoff value will not be considered. If no cutoff value is specified, all components in the database will be considered. The data for some contrasting soils of minor extent may not be in the database, and therefore are not considered.
Tie-break Rule: Higher
The tie-break rule indicates which value should be selected from a set of multiple candidate values, or which value should be selected in the event of a percent composition tie.
Custom Soil Resource Report
49
City Council Agenda November 7, 2023
References
American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition.
American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00.
Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31.
Federal Register. July 13, 1994. Changes in hydric soils of the United States.
Federal Register. September 18, 2002. Hydric soils of the United States.
Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States.
National Research Council. 1995. Wetlands: Characteristics and boundaries.
Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service.
U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262
Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section.
United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1.
United States Department of Agriculture, Natural Resources Conservation Service.
National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374
United States Department of Agriculture, Natural Resources Conservation Service.
National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 50
City Council Agenda November 7, 2023
United States Department of Agriculture, Natural Resources Conservation Service.
National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242
United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624
United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report
51
City Council Agenda November 7, 2023
City Council Agenda November 7, 2023
SECTION V
STORM DRAINS, STORM WATER QUALITY, AND WATERSHED PROTECTION V-1. GENERAL
It is the general purpose of these standards that storm water be contained and treated on the area to be developed. Adjacent improvements, existing or planned, will be free from flood hazard and will not receive a greater volume and intensity of storm water runoff than pre-existing conditions. Flood hazard is defined as potential damage by water having sufficient depth or velocity to damage improvements or to deposit or scour soil.
These specifications are intended to meet the requirements of the National Flood Insurance Program, the City’s Flood Plain Ordinance, and the City’s Storm Water Management Plan. These specifications reflect numeric storm water control criteria adopted by the Water Board on July 13, 2013 (including subsequent revisions) and modified as specifically applicable to the City of Paso Robles.
The lowest floor of any project that is located within a Special Flood Hazard Area and shown as an A, AE, AH or AO Zone shall be elevated above the highest adjacent grade to a height equal to or exceeding the depth number specified in feet on the Flood Insurance Rate Map (FIRM) by at least one foot, or elevated at least three feet above the highest adjacent grade if no depth number is specified.
Upon completion of a structure in a Special Flood Hazard Area, the elevation of the lowest floor including basement shall be certified by a registered professional engineer or land surveyor, and verified by the city building inspector to be properly elevated.
Such certification or verification shall be provided to the City Engineer.
Modification of a flood-plain shall be accomplished in accordance with Federal Management Emergency Management (FEMA) regulations and the City’s Floodplain Ordinance. The design engineer shall provide all data necessary for a Conditional Letter of Map Amendment (CLOMA) and a final Letter of Map Amendment (LOMA).
These standards are intended to provide general design criteria. Most design details are left to the responsibility of the consultant. The design standards contained herein are minimal and alternates may be approved, provided such alternates are to a higher standard than those set forth. Exceptions to these standards may be allowed by the City Engineer when it can be determined that such exceptions are in the best interest of the City.
FROM
CITY OF PASO ROBLES STANDARD SPECIFICATIONS AND DETAILS
City Council Agenda November 7, 2023
sustain a minimum infiltration rate of 5 inches per hour throughout the life of the project and must maximize runoff retention and pollutant removal.
A mixture of sand (60%-70%) meeting the specifications of ASTM C33 and compost (30%-40%) may be used. An alternative planting medium may be utilized if it is demonstrated to be equal or more effective at attenuating pollutants than the specified planting medium mixture. • Proper plant selection as provided by the Central Coast LID Initiative. • Subsurface drainage/storage (gravel) layer with an area equal to the biofiltration treatment system surface area and having a minimum depth of 12 inches.
• Underdrain with discharge elevation at top of gravel layer. • No compaction of soils beneath the biofiltration facility. • No liners or other barriers interfering with infiltration (excepting conditions were lateral infiltration is not feasible).
.
Non-Retention Based Treatment Systems:
Stormwater Control Measures that collectively achieve at least one of the following hydraulic sizing criteria for non-retention based treatment systems:
• Volume Design Basis: Treat stormwater runoff equal to the volume of runoff generated by the 85th percentile 24-hour storm event (0.80 inches). • Flow Design Basis: Treat the flow of runoff produced by a rain event equal to at least 0.2 inches per hour intensity.
(5) Performance Requirement No. 3: Runoff Retention
Projects that create and/or replace greater than or equal to 15,000 square feet of impervious surface are required to meet runoff retention performance requirements using Low Impact Development Standards. See Stormwater Technical Guide.
Prevent off-site discharge from events up to the 95th percentile 24-hour rainfall event (1.45 inches). Retention is to be achieved by optimizing infiltration.
Project design shall be founded in Low Impact Development principles. Site opportunities and constraints shall be identified and a site assessment shall include:
• Topography, structures, utilities, easements
• Hydrologic features including natural areas, wetlands, watercourses, seeps, or springs.
• Depth to seasonal high groundwater
• Locations of wells
• Depth to impervious bedrock
• Presence of unique geology
FROM
CITY OF PASO ROBLES STANDARD SPECIFICATIONS AND DETAILS
City Council Agenda November 7, 2023
• Geotechnical hazards
• Soil and/or groundwater contamination
• Soil types and hydrologic soil groups
• Vegetative cover/trees
• Run-on characteristics (estimate off-site runoff discharging to the project area)
• Existing drainage infrastructure
• Zoning, setbacks and open space requirements
• Define the development envelope and protected areas, identifying areas that are most suitable for development and areas to be left undisturbed. • Conserve natural areas including existing trees, vegetation and soils • Limit the overall impervious footprint of the project • Set back development from creeks, wetlands and riparian habitats • When runoff reduction measures and natural landscape areas have been maximized to the extent feasible storm water control measures shall be used to comply with performance requirements. Storm water control measures associated with small-scale, decentralized facilities designed to infiltrate, evapotranspirate, filter, or capture storm water shall be optimized. Refer to the City’s technical guidelines for sizing of storm water retention facilities.
(6) Performance Requirement No. 4: Peak Management
All projects that create and/or replace greater than or equal to 22,500 square feet of impervious surface in Watershed Management Zone 1 shall manage peak stormwater runoff as required below as well as meeting Water Quality and Runoff Retention requirements.
Post-development peak flows, discharged from the site, shall not exceed preproject peak flows for the 2 through 10-year storm events.
A Stormwater Control shall be provided in conformance with the Stormwater Technical Guide on File with the Stormwater Control Manager in the Department of Public Works.
(7) Operation and Maintenance for Structural Stormwater Control Measures The design of all structural stormwater control measures must be accompanied by an operation and maintenance (O and M) plan. Minimum requirements for the O and M plan are described in the City’s Technical Guide.
Prior to project acceptance or occupancy, verification of on-going maintenance of structural stormwater control measures must be established by legal binding agreements.
FROM
CITY OF PASO ROBLES STANDARD SPECIFICATIONS AND DETAILS
City Council Agenda November 7, 2023
B. Off-Site Hydrology, Cross-Culverts, Open Channels
1. Hydrology Calculations
The Rational Method shall be used to compute the total volume of runoff from a development with an area less than 200 acres. For drainage areas in excess of 200 acres, or where the design engineer determines that the Rational Method is not practical or appropriate, the design engineer shall provide all documents necessary to confirm computations.
All calculations shall be prepared by a registered professional engineer with a current license to practice in the State of California. The rainfall intensity curve included herein is available for use as part of the hydrology calculations. In computing runoff in a partial development, adequate provisions must be made for the drainage of the overall improvements and/or drainage tributary.
Hydrology calculations shall be based upon ultimate land use designations in accordance with the adopted General Plan.
FROM
CITY OF PASO ROBLES STANDARD SPECIFICATIONS AND DETAILS
City Council Agenda November 7, 2023
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FROM
CITY OF PASO ROBLES STANDARD SPECIFICATIONS AND DETAILS
City Council Agenda November 7, 2023
3. Open Channels
Open channels shall be designed based on Manning's equation. The impacts of culverts, bridges or other structures affecting the hydraulic performance of the channel shall be considered as appropriate.
The City Engineer may require more complete analysis if he/she determines conditions merit a more thorough study. This additional analysis may include determination of the water surface profile, analysis of critical sections, and analysis of erosion and/or sedimentation.
Maximum velocity for channels flowing full shall be limited to preclude erosion.
Freeboard of at least one foot based on 25-year volumes shall be provided for all channels. Lining treatments shall extend to the full height of freeboard. The 100-year discharge shall be contained within the banks or within the easement established for the channel. For natural waterways, the design flow may be allowed in the natural overflow area.
4. Retention Basins
Storm water retention for flood control purposes shall be applied as determined by the design engineer; typically where downstream conditions are constrained and properties are threatened or have been flooded in conditions existing prior to upstream development. Criteria for the design of retention basins may be reviewed on a case by case basis. Typically, the volume of storage for flood control purposes is based upon the post-development 100-year, 24-hour storm event.
5. Detention Basins
A detention basin is defined as a holding facility where the rate of flow from the basin is limited to that rate historically occurring prior to development. The volume of storage of a detention basin shall be determined by theoretically matching the historical hydrograph of flows leaving the previously undeveloped land under consideration.
6. Storm Drain Alignment Criteria
Storm drain lines shall be parallel with street centerlines to the extent practical and typically twelve feet southerly or easterly of the centerline (Standard Detail U-1).
FROM
CITY OF PASO ROBLES STANDARD SPECIFICATIONS AND DETAILS
City Council Agenda November 7, 2023
City Council Agenda November 7, 2023
DEPARTMENT OF PUBLIC WORKS - STANDARD DRAWINGS Scale:
Drawing
Issued:
August 2022 NTS
Revised: Revision No:
No: H-1
HYDROLOGY
AVERAGE ANNUAL RAINFALL MONTEREY COUNTY PACIFIC OCEAN SANTA BARBARA COUNTY 6 8
10 10
10 16
18 16
18 14
14 12
12 16
16 18
18 18
18 14 12
14 14
14 16
16 18
16 20 20
22 24 26
26 24
28 28
20 20
20 22
22 20
24 26
26 28
3230
32 34 36 38
36 36
30 32
34 40
42 40
40 SAN LUIS OBISPO COUNTY AVERAGE ANNUAL PRECIPITATION (JULY 1 THROUGH JUNE 30) FOR 42 YEAR PERIOD FROM 1955-56 THROUGH 1997-98) SAN LUIS OBISPO FLOOD CONTROL AND WATER CONSERVATION DISTRICT LOS OSOS MORRO BAYAVILA BEACHOCEANO SAN LUIS OBISPO 24 NIPOMOPOZO GROVER BEACH CAMBRIA SAN SIMEON 24 PASO ROBLES SAN MIGUEL 33 166 CUYAMA 101 1 KERN COUNTY 101 SANTA MARGARITA 227 1 41 41CRESTON TEMPLETON 58 229 46 46 SHANDON ARROYO GRANDE 1 CALIFORNIA VALLEY ATASCADERO PISMO BEACH LEGEND: 22 - AVERAGE ANNUAL PRECIPITATION (INCHES) Project Site
City Council Agenda November 7, 2023
DEPARTMENT OF PUBLIC WORKS - STANDARD DRAWINGS Scale:
Drawing
Issued:
August 2022 NTS
Revised: Revision No:
No: H-2
HYDROLOGY
TIME OF CONCENTRATION
TC
HOURS MINUTES
4 3
2 1 TIME OF FLOOD CONCENTRATION 18
16 14
12 9
8 7
6 4
3 5
20 30
40 240
180
120
70 80
90 100
60 50
10 LENGTH OF CHANNEL FROM MOST REMOTE POINT TO POINT OF CONCENTRATION L
MILES FEET
0.5 1
2 3
4 5
10 600
700
800
900
1200
1400
1600
1800
300
5000
4000
3000
2000
1000
500
400
200
HELEVATION IN FEET OF MOST REMOTE POINT OF WATERSHED ABOVE POINT OF CONCENTRATION. 900 800
700
600
15 FEET
5000
4000
3000
2000
1000
500
400
300
200
100
50 40
30 20
10 ( )
LEGEND:
Tc = TIME OF CONCENTRATION
IN HOURS.
L = LENGTH OF CHANNEL IN
MILES.
H = DIFFERENCE IN ELEVATION
BETWEEN MOST REMOTE
POINT AND THE POINT OF
CONCENTRATION IN FEET.
EQUATIONS FOR ESTIMATED
"TIME OF CONCENTRATION"
NOTES:
1. THIS NOMOGRAPH IS LIMITED TO
WATERSHED AREAS OF 200
ACRES OR LESS. FOR LARGER
WATERSHEDS REFER TO THE
DESIGN STANDARDS.
PROFILE STREAM
Tc =
0.3853
H
11.9L
H
L
POINT OF
CONCENTRATION
WATERSHED
LIMITS
REF: P.Z. KIRPICH, CIVIL ENGINEERING, Vol. 10, No. 6, JUNE 1940, p. 362 FOR WATERSHEDS LESS THAN 200 ACRES
City Council Agenda November 7, 2023
DEPARTMENT OF PUBLIC WORKS - STANDARD DRAWINGS Scale:
Drawing
Issued:
August 2022 NTS
Revised: Revision No:
No: H-3
HYDROLOGY
RUNOFF COEFFICIENTS-DEVELOPED
FOOT NOTES:
1. ESTIMATION OF COMPOSITE "C" VALUE USING ESTIMATED IMPERVIOUS AREAS AND STD. DWG. H-3a (TABLE 2) MAY BE REQUIRED BY THE DEPARTMENT. IMPERVIOUS AND PAVED AREAS SHALL USE C=0.95. 2, ALL VALUES SHOWN ARE INTENDED TO BE MINIMUMS. HIGHER VALUES MAY BE REQUIRED BY THE DEPARTMENT.
SOIL SLOPE
TYPE OF DEVELOPMENT TYPE <2% 2% to 10% >10% NOTE
RESIDENTIAL LOTS > 20,000 SF C 1,2
S 1,2
RESIDENTIAL LOTS 10,000 SF TO 19,999 SF C 0.40 0.45 0.55 1,2 " S 0.30 0.40 0.45 1,2
RESIDENTIAL LOTS 6,000 SF TO 9,999 SF C 0.45 0.55 0.65 1,2 " S 0.35 0.40 0.50 1,2
PLANNED DEVELOPMENTS (PUD) C 1,2
" S 1,2
APARTMENTS C 0.50 0.60 0.70 2
" S 0.40 0.50 0.60 2
INDUSTRIAL C 0.55 0.65 0.75 2
" S 0.45 0.55 0.65 2
COMMERCIAL C 0.75 0.80 0.85 2
" S 0.70 0.75 0.80 2
LEGEND:
C - CLAY, ADOBE, ROCK, OR IMPERVIOUS MATERIAL
S - SAND, GRAVEL, LOAM, OR PERVIOUS MATERIAL
NOTES:
1. COEFFICIENTS FOR RESIDENTIAL LOTS ASSUME TYPICAL SINGLE FAMILY RESIDENCE WITH ASSOCIATED GARAGE, DRIVEWAY, FLATWORK, AND LANDSCAPING. HIGHER DENSITY RESIDENTIAL DEVELOPMENTS MAY REQUIRE USING
COMPOSITE COEFFICIENT EVALUATED BY THE DESIGN ENGINEER AND BASED ON PROPOSED DEVELOPMENT IMPERVIOUS AREAS.
2. FOR ALL TYPES OF DEVELOPMENT, COEFFICIENTS ARE INCLUSIVE OF ONLY THE LOT AREA OUTSIDE THE RIGHT-OF-WAY (NET LOT AREA). PAVED SURFACES BETWEEN ROAD CENTERLINE AND RIGHT-OF-WAY SHALL BE EVALUATED SEPARATELY AND INCLUDED TO DETERMINE A COMPOSITE "C" FACTOR.
3. ALL IMPERVIOUS AREAS AND PAVED AREAS SHALL USE C = 0.95.
FOOT
0.25 0.35 0.40
0.35 0.40 0.50
0.60 0.65 0.70
0.65 0.70 0.75
TABLE 1: RATIONAL METHOD STANDARD RUNOFF COEFFICIENTS FOR
DEVELOPED AREAS
City Council Agenda November 7, 2023
DEPARTMENT OF PUBLIC WORKS - STANDARD DRAWINGS Scale:
Drawing
Issued:
August 2022 NTS
Revised: Revision No:
RUNOFF COEFFICIENTS-UNDEVELOPED No:
HYDROLOGY
H-3a
EXTREME HIGH NORMAL LOW
EXAMPLE:
GIVEN: AN UNDEVELOPED WATERSHED CONSISTING OF:
1. ROLLING TERRAIN WITH AVERAGE SLOPES OF 5%
2. CLAY SOILS
3. GOOD GRASSLAND AREA
4. NORMAL SURFACE DEPRESSIONS
FIND: THE RUNOFF COEFFICIENT FOR THE ABOVE WATERSHED
SOLUTION:
1. RELIEF = 0.14
2. SOIL INFILTRATION = 0.08
3. VEGETAL COVER = 0.04
4. SURFACE STORAGE = 0.06
ANSWER: THE RUNOFF COEFFICIENT, C = 0.14 + 0.08 + 0.04 + 0.06 = 0.32 RELIEF
SOIL
INFILTRATION
VEGETAL
COVER
SURFACE
STORAGE
0.28 TO 0.35
STEEP, RUGGED
TERRAIN WITH AVERAGE
SLOPES ABOVE 30%
0.20 TO 0.28
HILLY, WITH AVERAGE
SLOPES OF 10% TO 30%
0.14 TO 0.20 ROLLING,
WITH AVERAGE SLOPE
OF 5% TO 10%
0.08 TO 0.14
RELATIVELY FLAT LAND,
WITH AVERAGE SLOPES
OF 0% TO 5%
0.12 TO 0.16
NO EFFECTIVE SOIL
COVER, EITHER ROCK
OR THIN MANTLE OF
NEGLIGIBLE
INFILTRATION CAPACITY
0.08 TO 0.12
SLOW TO TAKE UP
WATER, CLAY OR
SHALLOW LOAM SOILS
OF LOW INFILTRATION
CAPACITY,
IMPERFECTLY OR
POORLY DRAINED
0.06 TO 0.08
NORMAL; WELL
DRAINED LIGHT OR
MEDIUM TEXTURED
SOILS, SANDY LOAMS,
SILT AND SILT LOAMS
0.04 TO 0.06
HIGH; DEEP SAND OR
OTHER SOILS THAT
TAKES UP WATER
READILY, VERY LIGHT
WELL DRAINED SOILS
0.12 TO 0.16
NO EFFECTIVE PLANT
COVER, BARE OR VERY
SPARSE COVER
0.08 TO 0.12
POOR TO FAIR;
CULTIVATION CROPS, OR
POOR NATURAL COVER,
LESS THAN 20% OF
DRAINAGE AREA OVER
GOOD COVER
0.06 TO 0.08
FAIR TO GOOD; ABOUT
50% OF AREA IN GOOD
GRASSLAND OR
WOODLAND, NOT MORE
THAN 50% OF AREA IN
CULTIVATED CROPS
0.04 TO 0.06
GOOD TO EXCELLENT;
ABOUT 90% OF
DRAINAGE AREA IN
GOOD GRASSLAND,
WOODLAND, OR
EQUIVALENT COVER
0.04 TO 0.06
HIGH; SURFACE
STORAGE, HIGH;
DRAINAGE SYSTEM NOT
SHARPLY DEFINED;
LARGE FLOOD PLAIN
STORAGE OR LARGE
NUMBER OF PONDS OR
MARSHES
0.06 TO 0.08
NORMAL;
CONSIDERABLE
SURFACE STORAGE,
LAKES AND POND
MARSHES
0.08 TO 0.10
LOW; WELL DEFINED
SYSTEM OF SMALL
DRAINAGE WAYS, NO
PONDS OR MARSHES
0.10 TO 0.12
NEGLIGIBLE SURFACE
DEPRESSIONS FEW AND
SHALLOW; DRAINAGE
WAYS STEEP AND
SMALL, NO MARSHES
(REFERENCES FIGURE 819.2A OF HIGHWAY DESIGN MANUAL)
TABLE 2: RATIONAL METHOD STANDARD RUNOFF COEFFICIENTS FOR
UNDEVELOPED AREAS
0.20 0.08 0.06 0.08 0.42 Subtotal
City Council Agenda November 7, 2023
DEPARTMENT OF PUBLIC WORKS - STANDARD DRAWINGS Scale:
Drawing
Issued:
August 2022 NTS
Revised: Revision No:
RAINFALL INTENSITY No:
HYDROLOGY
H-4
Duration
TABLE 1: ANNUAL RAINFALL < 14"
10 Min 15 Min 30 Min 1 Hr 2 Hr 3 Hr 6 Hr 10 Hr
2 1.00 0.90 0.60 0.40 0.26 0.22 0.18 0.14
5 1.40 1.20 0.80 0.50 0.37 0.32 0.25 0.20
10 1.70 1.40 1.00 0.60 0.44 0.38 0.30 0.23
25 2.00 1.70 1.10 0.70 0.54 0.47 0.37 0.28
50 2.20 1.90 1.30 0.80 0.60 0.53 0.44 0.34
100 2.40 2.10 1.40 0.90 0.65 0.59 0.48 0.36
10 Min 15 Min 30 Min 1 Hr 2 Hr 3 Hr 6 Hr 10 Hr
1.30 1.10 0.80 0.50 0.35 0.30 0.23 0.18
1.90 1.60 1.10 0.70 0.49 0.42 0.33 0.26
2.30 1.90 1.30 0.80 0.60 0.51 0.40 0.30
2.60 2.20 1.50 1.00 0.71 0.63 0.50 0.38
3.00 2.50 1.70 1.10 0.81 0.74 0.60 0.47
3.20 2.70 1.90 1.20 0.90 0.80 0.65 0.49
10 Min 15 Min 30 Min 1 Hr 2 Hr 3 Hr 6 Hr 10 Hr
1.70 1.40 1.00 0.65 0.44 0.37 0.29 0.22
2.30 1.90 1.30 0.85 0.60 0.52 0.41 0.33
2.80 2.40 1.60 1.03 0.74 0.64 0.50 0.38
3.20 2.70 1.90 1.20 0.92 0.80 0.64 0.50
3.70 3.10 2.10 1.40 1.05 0.92 0.74 0.58
4.00 3.40 2.30 1.50 1.13 1.00 0.80 0.62
10 Min 15 Min 30 Min 1 Hr 2 Hr 3 Hr 6 Hr 10 Hr
2.10 1.80 1.20 0.77 0.55 0.47 0.36 0.28
2.80 2.50 1.70 1.05 0.76 0.64 0.52 0.42
3.60 3.00 2.10 1.30 0.92 0.81 0.64 0.48
3.90 3.50 2.40 1.50 1.10 0.98 0.78 0.60
4.50 3.90 2.60 1.70 1.28 1.15 0.94 0.72
5.00 4.30 2.90 1.85 1.40 1.25 0.98 0.76
Duration
TABLE 2: ANNUAL RAINFALL 14" TO 17"
Duration
TABLE 3: ANNUAL RAINFALL 18" TO 21"
Duration
TABLE 4: ANNUAL RAINFALL 22" TO 28" (Years) Recurrence Interval Recurrence Interval (Years) 100
50 25
10 5
2 2
5 10
25 50
100 (Years) Recurrence Interval
2 5
10 25
50 100 (Years) Recurrence Interval
Intensity (inches/hour)
Intensity (inches/hour)
Intensity (inches/hour)
Intensity (inches/hour)
City Council Agenda November 7, 2023
City Council Agenda November 7, 2023
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NOAA ATLAS 14,
VOLUME 6, VERSION 2
FOR PASO ROBLES, CA
City Council Agenda November 7, 2023
FROM
NOAA ATLAS 14, VOLUME 6,
VERSION 2 FOR PASO ROBLES, CA
City Council Agenda November 7, 2023
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City Council Agenda November 7, 2023
APPENDIX C
Appendix C – Preliminary Drainage Design Calculations
• Existing and Proposed Hydrologic Calculations
• Existing and Proposed Land Use Data
• Time of Concentration Calculations
• HydroCAD Drainage Results – Existing Site
o 25-Year, 50-Year, and 100-Year Design Storms
• HydroCAD Drainage Results – Proposed Site
o 25-Year, 50-Year, and 100-Year Design Storms
• Ardmore Bypass Culvert analysis – 25-year and 100-year storm event
City Council Agenda November 7, 2023
Ardmore Project
Location: Paso Robles, CA
Project: 0751-0005 Ardmore
Date: 2/16/2022
By: ZKP
Overall Hydrologic Calculations - SBUH method in HydroCAD 95th inches 1.45
2 YR inches 2.14
10 YR inches 3.74
25 YR inches 4.70
50 YR inches 5.42
100 YR inches 6.16
Pre-Dev.
Total Area
(ac)
Post-Dev.
Total Area
(ac)
Storm Pre-Developed
Flow, Q (cfs)
Post-Developed
Flow, Q (cfs)
Proposed Structural
Control Measures
(SCM)
95th - -
2 YR 32.51 31.75
10 YR 61.76 59.90
25 YR 72.83 71.33
50 YR 85.55 83.41
100 YR 93.67 90.48
95th Data Unknown -
2 YR 1.02 0.04
10 YR 2.11 0.59
25 YR 2.46 1.65
50 YR 2.97 2.53
100 YR 3.54 3.42
95th 0.01 0.03
2 YR 0.15 0.07
10 YR 0.74 0.12
25 YR 1.17 0.15
50 YR 1.52 0.18
100 YR 1.89 0.20
95th - -
2 YR 0.56 -
10 YR 2.94 0.54
25 YR 4.70 1.37
50 YR 6.11 3.36
100 YR 7.62 6.81
71.33 71.33
Pre-Dev.
Total Area
(ac)
Post-Dev.
Total Area
(ac)
Storm Pre-Developed
Flow, Q (cfs)
Post-Developed
Flow, Q (cfs)
95th 0.01 0.03
2 YR 2.97 0.59
10 YR 12.23 5.83
25 YR 18.62 11.96
50 YR 23.99 17.32
100 YR 29.75 23.94
2 2
2 2
1 Roadside bioretention
swales, StormTech
Chamber:
(B1 = 78' x 88')
(B2 = 178' x 23')
Ardmore Industrial
* See NOAA Atlas 14 Rainfall data (24-hr storm
duration)
3.27 Drainage Area Subtotal
Antecedent Moisture Condition (AMC) utilized in
HydroCAD.
14.06 64.43 64.46
2.80 0.27
14.06 3.79
2.82 0.80
Pre- vs. Post-Development Peak Flow Summary - OVERALL PROJECT SITE Project Site
Drainage Notes
A bypass culvert is proposed to
intercept offsite run-on from the
south (EX1 offsite) and convey it
to Outlet A following historic
drainage patterns.
Pre-developed data referenced
from Daniels Commercial drainage
report by Roberts Eng. (2019,
2020)
Designed onsite runoff to north
along Ardmore Road following
historic drainage patterns
Rainfall Event Data
Outlet D
Onsite Runoff (C)
Outlet B
Outlet A
Outlet Location
Pre- vs. Post-Development Peak Flow Summary - OUTLETS
Roadside bioretention
swales, StormTech
Chamber:
(A =257' x 52')
Detention Basin with
metered SD outlet.
Underground
bioretention trench
along basin bottom
Roadside bioretention
swale
Antecedent Moisture Condition
2 2022_Ardmore Drainage Calculations_NEW infilt rates Page 940 of 1329 Page 1 of 2 City Council Agenda November 7, 2023
Ardmore Project
Location: Paso Robles, CA
Project: 0751-0005 Ardmore
Date: 2/16/2022
By: ZKP
Overall Hydrologic Calculations - SBUH method in HydroCAD WSHD Outlet
Location
Total Area
(sf)
Total Area
(ac) Weighted CN Land Type Description
Time of Conc.
(min) Storm Flow, Q (cfs)
2 YR 31.27
10 YR 55.32
25 YR 62.54
50 YR 72.16
100 YR 76.97
95th -
2 YR 1.24
10 YR 6.44
25 YR 10.29
50 YR 13.39
100 YR 16.70
95th Data Unknown
2 YR 1.02
10 YR 2.11
25 YR 2.46
50 YR 2.97
100 YR 3.54
95th -
2 YR 0.56
10 YR 2.94
25 YR 4.70
50 YR 6.11
100 YR 7.62
95th 0.01
2 YR 0.15
10 YR 0.74
25 YR 1.17
50 YR 1.52
100 YR 1.89
Subtotal 3,106,984 71.33
DMA Outlet
Location
Total Area
(sf)
Total Area
(ac) Weighted CN Land Type Description
Time of Conc.
(min) Storm Flow, Q (cfs)
95th -
2 YR 0.48
10 YR 4.58
25 YR 8.79
50 YR 11.25
100 YR 13.51
95th -
2 YR 0.04
10 YR 0.59
25 YR 1.65
50 YR 2.53
100 YR 3.42
95th 0.03
2 YR 0.07
10 YR 0.12
25 YR 0.15
50 YR 0.18
100 YR 0.20
95th -
2 YR -
10 YR 0.54
25 YR 1.37
50 YR 3.36
100 YR 6.81
Subtotal 612,363 14.06
Developed
* Calculated time of concentrations values were found to be less than the minimum 6-minute standard set by the City of Paso Robles Standards.
EX1
(offsite)
EX1
(onsite)
2,494,621
312,111
C 11,941 0.27 Developed 98 6.00
D 165,076 3.79 Developed 95 6.00
B1 + B2 121,873 2.80 95 6.00
* Calculated time of concentrations values were found to be less than the minimum 6-minute standard set by the City of Paso Robles Standards.
Proposed/ Post-developed Hydrology - Land Use Data & Peak Flow
57.27 See Offsite
Hydrology
Calculations
(Rational
Method)
OFFSITE
RUN-ON
Undeveloped.
Rural grassland/
open space, few
trees
11.04 Outlet A
(Exist. double
24" SD pipes)
7.17 74 6.00
ONSITE
Undeveloped.
Rural grassland/
open space with
few trees
(Data referenced from 2019 Daniels Commercial
drainage report by Roberts Engineering - see
"Tate Property/ Offsite flow from east"
calculations)
Developed 95 6.00
Onsite Runoff
(C)
(Sheet flow
runoff to north
along Ardmore
Rd)
Outlet B
(Exist 12"
culvert)
Undeveloped.
Rural grassland/
agricultural with
few trees
6.00 EX4 34,918 0.80
Outlet D
(Surface
runoff/ sheet
flow to
northwest)
74 Mostly
undeveloped
(single ag
structure). Rural
grassland/
agricultural, few
6.00 EX3 142,459 3.27 74
** DMA C storm drain system has been designed to over-retain and detain stormwater to account for DMA E onsite stormwater runoff.
Outlet A
(Exist. double
24" SD pipes)
Outlet B
(Prop. curb
inlet at exist
12" culvert)
Outlet D
(Prop. basin
outlet with
metered flow
to northwest)
Onsite Runoff
(C)
(Sheet flow
runoff to north
along Ardmore
Rd)
Existing/ Pre-developed Hydrology - Land Use Data & Peak Flow A 313,474 7.20
EX2 122,877 2.82
2022_Ardmore Drainage Calculations_NEW infilt rates Page 941 of 1329 Page 2 of 2 City Council Agenda November 7, 2023
Ardmore Project
Location: Paso Robles, CA
Project: 0751-0005 Ardmore
Date: 2/16/2022
By: ZKP
Offsite Hydrologic Calculations - Rational method
2 YR 1.30 in/ hr
10 YR in/ hr 2.30
25 YR in/ hr 2.60
50 YR in/ hr 3.00
100 YR in/ hr 3.20
DMA Outlet
Location
Total Area
(sf)
Total Area
(ac) C
Land Type
Description
Time of
Conc. (min) Storm Intensity, I (in/hr) Flow, Q (cfs)
2 YR 1.30 31.27
10 YR 2.30 55.32
25 YR 2.60 62.54
50 YR 3.00 72.16
100 YR 3.20 76.97
2,494,621 57.27
Land Type C-Value
Rural
grass/ ag SF 0.42 2,494,621 Undeveloped
1,047,741
2,494,621 57.27 ac
0.42 Description C-value
Relief 0.20
Soil Infiltration 0.08
Vegetal Cover 0.06
Surface Storage 0.08
Total 0.42
Rainfall Event Data
* See 2022 County of San Luis Obispo Public
Improvement Standards H-4, Table 2
Outlet A
(Exist. double
24" SD pipes)
EX1 (offsite)
Subtotal
Existing/ Pre-developed Offsite Hydrology Conditions
* Calculated time of concentrations values were found to be less than the minimum 10-minute standard set by the 2022 County of San Luis Obispo Public Improvements Standards.
EX1
(offsite) 2,494,621 57.27 0.42
OFFSITE
RUN-ON
Undeveloped.
Rural grassland/
open space, few
trees
11.04 Area
ΣCA
Total DMA Area
Weighted C-Value
Undeveloped Area C-Value (SLO County detail H-3a)
Relatively flat land, with average slopes 0-5%
Slow to take up water, clay or shallow loam soils
Good to excellent - 90% or more area is good
grassland or equiv. cover
Low - well defined system of small drainage ways
with no ponds or marshes
Rural/ Ag
Land
2022_Ardmore Drainage Calculations_NEW infilt rates Page 1 of 1 Page 942 of 1329 City Council Agenda November 7, 2023
Project: 751-005 Ardmore
Date: 2/14/2022
By: ZKP
Existing/ Pre-developed Watershed Land Use
(For HydroCAD model use)
Land Type Total Area (sf) % of Total Area SF to Acre
Impervious (Imp) 3,223 0.5% 43,560
Pervious (P) 609,141 99.5%
Total Area 612,364 100.0%
Catchment Catchment Area
(sf) P/I % of Catchment
Breakdown
Area (sf)
Breakdown Area
(acre) Notes
P 100% 2,494,621 57.27
Imp 0% - -
P 100% 2,494,621 57.27
Imp 0% - -
100% 2,494,621 57.27
.
Catchment Catchment Area
(sf) P/I % of Catchment
Breakdown
Area (sf)
Breakdown Area
(acre) Notes
P 100% 312,111 7.17
Imp 0% - -
P 100% 312,111 7.17
Imp 0% - -
100% 312,111 7.17
.
Catchment Catchment Area
(sf) P/I % of Catchment
Breakdown
Area (sf)
Breakdown Area
(acre) Notes
P 98% 120,160 2.76
Imp 2% 2,717 0.06
P 98% 120,160 2.76
Imp 2% 2,717 0.06
100% 122,877 2.82
.
Catchment Catchment Area
(sf) P/I % of Catchment
Breakdown
Area (sf)
Breakdown Area
(acre) Notes
P 100% 142,459 3.27
Imp 0% - -
P 100% 142,459 3.27
Imp 0% - -
100% 142,459 3.27
.
Catchment Catchment Area
(sf) P/I % of Catchment
Breakdown
Area (sf)
Breakdown Area
(acre) Notes
P 99% 34,412 0.79
Imp 1% 506 0.01
P 99% 34,412 0.79
Imp 1% 506 0.01
100% 34,918 0.80
.
71.33 3,106,984
Exist Outlet A
Exist Outlet B
Exist Outlet A
Surface runoff to
northeast
Exist Outlet B
Subtotal 122,877
EX4 34,918
Subtotal 142,459
EX3 142,459
EX2 122,877
EX1 (onsite) 312,111
Subtotal 312,111
Existing Watershed Area
Subtotal 34,918
EX1 (offsite) 2,494,621
Subtotal 2,494,621
Existing/ Pre-developed Site Summary (excludes EX1 offsite)
14.06 Total Area (ac)
0.07 13.98
2022_Ardmore Drainage Calculations_NEW infilt rates Page 943 of 1329 Page 1 of 1 City Council Agenda November 7, 2023
Project: 751-005 Ardmore
Date: 2/14/2022
By: ZKP
Proposed/ Post-developed DMA Land Use
(For HydroCAD model use)
Land Type Total Area (sf) % of Total Area SF to Acre
Impervious (Imp) 501,730 81.9% 43,560
Pervious (P) 110,633 18.1%
Total Area 612,363 100.0%
Catchment Catchment Area
(sf) P/I % of Catchment
Breakdown
Area (sf)
Breakdown Area
(acre) Notes
P 14% 37,042 0.85
Imp 86% 227,546 5.22
P 14% 6,844 0.16
Imp 86% 42,041 0.97
P 14% 43,886 1.01
Imp 86% 269,587 6.19
100% 313,474 7.20
.
P 24% 15,178 0.35
Imp 76% 44,042 1.01
P 24% 1,256 0.03
Imp 76% 9,109 0.21
P 24% 16,434 0.38
Imp 76% 53,151 1.22
100% 69,586 1.60
.
P 24% 4,163 0.10
Imp 76% 48,124 1.10
P 24% 4,163 0.10
Imp 76% 48,124 1.10
100% 52,287 1.20
P 10% 2,633 0.06
Imp 90% 7,087 0.16
P 10% - -
Imp 90% 2,221 0.05
P 10% 2,633 0.06
Imp 90% 9,308 0.21
100% 11,941 0.27
.
P 26% 43,517 1.00
Imp 74% 121,559 2.79
P 26% 43,517 1.00
Imp 74% 121,559 2.79
100% 165,076 3.79
.
612,363 14.06
Subtotal (D) 165,076
Total Project Area
A1 264,589
A2
B1b
Subtotal (A)
Subtotal (B) 52,287
B2a 52,287
Basin w/ Bioretention,
Outlet D
Roadside Bioswale,
Run-off to the north
C2 2,221 Onsite run-off to the
north
Subtotal (C)
D1 165,076
11,941
Roadside Bioswale,
Outlet A 48,885
Proposed/ Post-developed Site Summary
C1 9,720
59,221
10,365
Subtotal (B) 69,586
313,474
B1a
StormTech Chambers,
Outlet B
Total Area (ac)
2.54 11.52
14.06 StormTech Chambers,
Outlet B
Roadside Bioswale,
Outlet B
StormTech Chambers,
Outlet A
2022_Ardmore Drainage Calculations_NEW infilt rates Page 944 of 1329 Page 1 of 2 City Council Agenda November 7, 2023
Project: 751-005 Ardmore
Date: 2/16/2022
By: ZKP
Time of Concentration calculations
References:
2022 County of San Luis Obispo Public Improvement Standard H-2 Watershed Outlet L (Mile) H (ft) tc (hr) tc (min)
EX1 (offsite) 0.54 152 0.18 11.04 6.00
EX1 (onsite) 0.11 19 0.07 4.06 6.00
EX2 Outlet B (Exist 12" culvert)
EX3 Outlet D (Surface runoff/
sheet flow to northwest) 0.11 19 0.06 3.89 6.00
EX4
Onsite Runoff (C)
(Sheet flow runoff to north
along Ardmore Rd)
0.05 6 0.05 2.74 6.00
DMA Outlet L (MI) H tc (hr) tc (min)
A Exist. Dbl. 24" SD pipes 0.11 13.0 0.08 4.77 6.00
B Proposed Curb Inlet 0.06 3.9 0.06 3.77 6.00
C Onsite Runoff 0.09 4.7 0.09 5.49 6.00
D Basin Outlet 0.13 15.0 0.08 4.97 6.00
Existing Conditions
Proposed Conditions
City of Paso
Robles min.
tc (min)
City of Paso
Robles min.
tc (min)
Outlet A (Exist. double 24"
SD pipes)
(Data referenced from 2019 Daniels Commercial
drainage report by Roberts Engineering)
2022_Ardmore Drainage Calculations_NEW infilt rates Page 945 of 1329 Page 1 of 1 City Council Agenda November 7, 2023 Calculated using
Rational Method (see
report Appendix)
Exist WSHD 2 (EX2)
Data from Roberts Eng.
reports (2019/20) Exist WSHD 1
(EX1offsite)
EX1*
Exist WSHD 1 (onsite)
EX3
Exist WSHD 3
EX4
Exist WSHD 4
Routing Diagram for 2022_Ardmore_Exist
Prepared by Wallace Group, Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Subcat Reach Pond Link
EX1 (offsite) not included in this HyrdoCAD report
(See "Offsite Hydrology Calcs - Rational Method" by Wallace Group in Appendix C) EX2 not included in this HyrdoCAD report
(See data from 2019/2020 Daniels Woodlands drainage reports by Roberts Engineering, referenced in "Overall Hydrology Calculations" by Wallace Group in Appendix C)
EXISTING ROUTING DIAGRAM
City Council Agenda November 7, 2023
2022_Ardmore_Exist Table of Contents
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC
TABLE OF CONTENTS
Project Reports
1 Routing Diagram
2 Rainfall Events Listing (selected events)
3 Area Listing (all nodes)
4 Soil Listing (all nodes)
5 Ground Covers (all nodes)
25-YR Event
6 Node Listing
7 Subcat EX1*: Exist WSHD 1 (onsite)
8 Subcat EX3: Exist WSHD 3
9 Subcat EX4: Exist WSHD 4
50-YR Event
10 Node Listing
11 Subcat EX1*: Exist WSHD 1 (onsite)
12 Subcat EX3: Exist WSHD 3
13 Subcat EX4: Exist WSHD 4
100-YR Event
14 Node Listing
15 Subcat EX1*: Exist WSHD 1 (onsite)
16 Subcat EX3: Exist WSHD 3
17 Subcat EX4: Exist WSHD 4
City Council Agenda November 7, 2023
2022_Ardmore_Exist
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 2 Rainfall Events Listing (selected events)
Event# Event
Name
Storm Type Curve Mode Duration
(hours)
B/B Depth
(inches)
AMC
1 25-YR Type I 24-hr Default 24.00 1 4.70 2
2 50-YR Type I 24-hr Default 24.00 1 5.42 2
3 100-YR Type I 24-hr Default 24.00 1 6.16 2
City Council Agenda November 7, 2023
2022_Ardmore_Exist
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 3 Area Listing (all nodes)
Area
(acres)
CN Description
(subcatchment-numbers)
0.012 98 Ag Building, HSG C (EX4)
11.225 74 Pasture/grassland/range, Good, HSG C (EX1*, EX3, EX4)
11.237 74 TOTAL AREA
City Council Agenda November 7, 2023
2022_Ardmore_Exist
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 4 Soil Listing (all nodes)
Area
(acres)
Soil
Group
Subcatchment
Numbers
0.000 HSG A
0.000 HSG B
11.237 HSG C EX1*, EX3, EX4
0.000 HSG D
0.000 Other
11.237 TOTAL AREA
City Council Agenda November 7, 2023
2022_Ardmore_Exist
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 5 Ground Covers (all nodes)
HSG-A
(acres)
HSG-B
(acres)
HSG-C
(acres)
HSG-D
(acres)
Other
(acres)
Total
(acres)
Ground
Cover
Subcatchment
Numbers
0.000 0.000 0.012 0.000 0.000 0.012 Ag Building EX
4 0.000 0.000 11.225 0.000 0.000 11.225 Pasture/grassland/range, Good EX 1*,
EX
3,
EX
4 0.000 0.000 11.237 0.000 0.000 11.237 TOTAL AREA
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 6 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SBUH method, Split Pervious/Imperv.
Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment EX1*: Exist WSHD 1 (onsite)Runoff Area=312,111 sf 0.00% Impervious Runoff Depth=2.13" Tc=6.0 min CN=74/0 Runoff=10.29 cfs 1.270 af
Subcatchment EX3: Exist WSHD 3 Runoff Area=142,459 sf 0.00% Impervious Runoff Depth=2.13" Tc=6.0 min CN=74/0 Runoff=4.70 cfs 0.580 af
Subcatchment EX4: Exist WSHD 4 Runoff Area=34,918 sf 1.45% Impervious Runoff Depth=2.16" Tc=6.0 min CN=74/98 Runoff=1.17 cfs 0.144 af
Total Runoff Area = 11.237 ac Runoff Volume = 1.994 af Average Runoff Depth = 2.13"
99.90% Pervious = 11.225 ac 0.10% Impervious = 0.012 ac
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment EX1*: Exist WSHD 1 (onsite)
Runoff = 10.29 cfs @ 9.95 hrs, Volume= 1.270 af, Depth= 2.13" Routed to nonexistent node A
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 25-YR Rainfall=4.70"
Area (sf) CN Description
312,111 74 Pasture/grassland/range, Good, HSG C
312,111 74 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, Calculated
Subcatchment EX1*: Exist WSHD 1 (onsite)
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
11 10
9 8
7 6
5 4
3 2
1 0
Type I 24-hr
25-YR Rainfall=4.70"
Runoff Area=312,111 sf
Runoff Volume=1.270 af
Runoff Depth=2.13"
Tc=6.0 min
CN=74/0
10.29 cfs
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment EX3: Exist WSHD 3
Runoff = 4.70 cfs @ 9.95 hrs, Volume= 0.580 af, Depth= 2.13" Routed to nonexistent node D
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 25-YR Rainfall=4.70"
Area (sf) CN Description
142,459 74 Pasture/grassland/range, Good, HSG C
142,459 74 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, City of Paso Robles minimum
Subcatchment EX3: Exist WSHD 3
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
5 4
3 2
1 0
Type I 24-hr
25-YR Rainfall=4.70"
Runoff Area=142,459 sf
Runoff Volume=0.580 af
Runoff Depth=2.13"
Tc=6.0 min
CN=74/0
4.70 cfs
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment EX4: Exist WSHD 4
Runoff = 1.17 cfs @ 9.95 hrs, Volume= 0.144 af, Depth= 2.16" Routed to nonexistent node C
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 25-YR Rainfall=4.70"
Area (sf) CN Description
34,412 74 Pasture/grassland/range, Good, HSG C
* 506 98 Ag Building, HSG C
34,918 74 Weighted Average
34,412 74 98.55% Pervious Area
506 98 1.45% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, City of Paso Robles minimum
Subcatchment EX4: Exist WSHD 4
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
1 0
Type I 24-hr
25-YR Rainfall=4.70"
Runoff Area=34,918 sf
Runoff Volume=0.144 af
Runoff Depth=2.16"
Tc=6.0 min
CN=74/98
1.17 cfs
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 10 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SBUH method, Split Pervious/Imperv.
Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment EX1*: Exist WSHD 1 (onsite)Runoff Area=312,111 sf 0.00% Impervious Runoff Depth=2.70" Tc=6.0 min CN=74/0 Runoff=13.39 cfs 1.614 af
Subcatchment EX3: Exist WSHD 3 Runoff Area=142,459 sf 0.00% Impervious Runoff Depth=2.70" Tc=6.0 min CN=74/0 Runoff=6.11 cfs 0.737 af
Subcatchment EX4: Exist WSHD 4 Runoff Area=34,918 sf 1.45% Impervious Runoff Depth=2.74" Tc=6.0 min CN=74/98 Runoff=1.52 cfs 0.183 af
Total Runoff Area = 11.237 ac Runoff Volume = 2.534 af Average Runoff Depth = 2.71"
99.90% Pervious = 11.225 ac 0.10% Impervious = 0.012 ac
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 11 Summary for Subcatchment EX1*: Exist WSHD 1 (onsite)
Runoff = 13.39 cfs @ 9.95 hrs, Volume= 1.614 af, Depth= 2.70" Routed to nonexistent node A
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 50-YR Rainfall=5.42"
Area (sf) CN Description
312,111 74 Pasture/grassland/range, Good, HSG C
312,111 74 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, Calculated
Subcatchment EX1*: Exist WSHD 1 (onsite)
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
14 13
12 11
10 9
8 7
6 5
4 3
2 1
0 Type I 24-hr
50-YR Rainfall=5.42"
Runoff Area=312,111 sf
Runoff Volume=1.614 af
Runoff Depth=2.70"
Tc=6.0 min
CN=74/0
13.39 cfs
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 12 Summary for Subcatchment EX3: Exist WSHD 3
Runoff = 6.11 cfs @ 9.95 hrs, Volume= 0.737 af, Depth= 2.70" Routed to nonexistent node D
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 50-YR Rainfall=5.42"
Area (sf) CN Description
142,459 74 Pasture/grassland/range, Good, HSG C
142,459 74 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, City of Paso Robles minimum
Subcatchment EX3: Exist WSHD 3
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
6 5
4 3
2 1
0 Type I 24-hr
50-YR Rainfall=5.42"
Runoff Area=142,459 sf
Runoff Volume=0.737 af
Runoff Depth=2.70"
Tc=6.0 min
CN=74/0
6.11 cfs
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 13 Summary for Subcatchment EX4: Exist WSHD 4
Runoff = 1.52 cfs @ 9.95 hrs, Volume= 0.183 af, Depth= 2.74" Routed to nonexistent node C
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 50-YR Rainfall=5.42"
Area (sf) CN Description
34,412 74 Pasture/grassland/range, Good, HSG C
* 506 98 Ag Building, HSG C
34,918 74 Weighted Average
34,412 74 98.55% Pervious Area
506 98 1.45% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, City of Paso Robles minimum
Subcatchment EX4: Exist WSHD 4
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
1 0
Type I 24-hr
50-YR Rainfall=5.42"
Runoff Area=34,918 sf
Runoff Volume=0.183 af
Runoff Depth=2.74"
Tc=6.0 min
CN=74/98
1.52 cfs
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 14 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SBUH method, Split Pervious/Imperv.
Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment EX1*: Exist WSHD 1 (onsite)Runoff Area=312,111 sf 0.00% Impervious Runoff Depth=3.32" Tc=6.0 min CN=74/0 Runoff=16.70 cfs 1.982 af
Subcatchment EX3: Exist WSHD 3 Runoff Area=142,459 sf 0.00% Impervious Runoff Depth=3.32" Tc=6.0 min CN=74/0 Runoff=7.62 cfs 0.905 af
Subcatchment EX4: Exist WSHD 4 Runoff Area=34,918 sf 1.45% Impervious Runoff Depth=3.36" Tc=6.0 min CN=74/98 Runoff=1.89 cfs 0.224 af
Total Runoff Area = 11.237 ac Runoff Volume = 3.111 af Average Runoff Depth = 3.32"
99.90% Pervious = 11.225 ac 0.10% Impervious = 0.012 ac
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 15 Summary for Subcatchment EX1*: Exist WSHD 1 (onsite)
Runoff = 16.70 cfs @ 9.95 hrs, Volume= 1.982 af, Depth= 3.32" Routed to nonexistent node A
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 100-YR Rainfall=6.16"
Area (sf) CN Description
312,111 74 Pasture/grassland/range, Good, HSG C
312,111 74 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, Calculated
Subcatchment EX1*: Exist WSHD 1 (onsite)
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
18 17
16 15
14 13
12 11
10 9
8 7
6 5
4 3
2 1
0 Type I 24-hr
100-YR Rainfall=6.16"
Runoff Area=312,111 sf
Runoff Volume=1.982 af
Runoff Depth=3.32"
Tc=6.0 min
CN=74/0
16.70 cfs
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 16 Summary for Subcatchment EX3: Exist WSHD 3
Runoff = 7.62 cfs @ 9.95 hrs, Volume= 0.905 af, Depth= 3.32" Routed to nonexistent node D
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 100-YR Rainfall=6.16"
Area (sf) CN Description
142,459 74 Pasture/grassland/range, Good, HSG C
142,459 74 100.00% Pervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, City of Paso Robles minimum
Subcatchment EX3: Exist WSHD 3
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
8 7
6 5
4 3
2 1
0 Type I 24-hr
100-YR Rainfall=6.16"
Runoff Area=142,459 sf
Runoff Volume=0.905 af
Runoff Depth=3.32"
Tc=6.0 min
CN=74/0
7.62 cfs
City Council Agenda November 7, 2023
2022_Ardmore_Exist Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 12/8/2022
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 17 Summary for Subcatchment EX4: Exist WSHD 4
Runoff = 1.89 cfs @ 9.95 hrs, Volume= 0.224 af, Depth= 3.36" Routed to nonexistent node C
Runoff by SBUH method, Split Pervious/Imperv., Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Type I 24-hr 100-YR Rainfall=6.16"
Area (sf) CN Description
34,412 74 Pasture/grassland/range, Good, HSG C
* 506 98 Ag Building, HSG C
34,918 74 Weighted Average
34,412 74 98.55% Pervious Area
506 98 1.45% Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
6.0 Direct Entry, City of Paso Robles minimum
Subcatchment EX4: Exist WSHD 4
Runoff
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
2 1
0 Type I 24-hr
100-YR Rainfall=6.16"
Runoff Area=34,918 sf
Runoff Volume=0.224 af
Runoff Depth=3.36"
Tc=6.0 min
CN=74/98
1.89 cfs
City Council Agenda November 7, 2023
City Council Agenda November 7, 2023
A1
DMA A-1
A2
DMA A-2
B1a
Catch B-1a
B1b
Catch B-1b
B2a
Catch B-2a
C1
Catch C-1
C2
Catch C-2
D1
DMA D-1
LID A1
A-1 Chambers
LID A2
A-2 Bioretention
LID B1a
B-1a Chambers
LID B1b
B-1b Bioretention
LID B2a
B-2a Chambers
LID C2
C-1 Bioretention
LID D
Basin
A
Outlet A
B
Outlet B
C
Outlet C
D
Outlet D
Routing Diagram for 2022_Ardmore
Prepared by Wallace Group, Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Subcat Reach Pond Link
PROPOSED ROUTING DIAGRAM
City Council Agenda November 7, 2023
2022_Ardmore Table of Contents
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC
TABLE OF CONTENTS
Project Reports
1 Routing Diagram
2 Rainfall Events Listing (selected events)
3 Area Listing (all nodes)
4 Soil Listing (all nodes)
5 Ground Covers (all nodes)
6 Pipe Listing (all nodes)
25-YR Event
7 Node Listing
8 Link A: Outlet A
9 Link B: Outlet B
10 Link C: Outlet C
11 Link D: Outlet D
50-YR Event
12 Node Listing
13 Link A: Outlet A
14 Link B: Outlet B
15 Link C: Outlet C
16 Link D: Outlet D
100-YR Event
17 Node Listing
18 Link A: Outlet A
19 Link B: Outlet B
20 Link C: Outlet C
21 Link D: Outlet D
City Council Agenda November 7, 2023
2022_Ardmore
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 2 Rainfall Events Listing (selected events)
Event# Event
Name
Storm Type Curve Mode Duration
(hours)
B/B Depth
(inches)
AMC
1 25-YR Type I 24-hr Default 24.00 1 4.70 2
2 50-YR Type I 24-hr Default 24.00 1 5.42 2
3 100-YR Type I 24-hr Default 24.00 1 6.16 2
City Council Agenda November 7, 2023
2022_Ardmore
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 3 Area Listing (all nodes)
Area
(acres)
CN Description
(subcatchment-numbers)
8.728 98 Impervious, HSG C (A1, A2, B1a, B1b, B2a, C1, C2)
2.540 79 Landscaped, 50-75% Grass cover, Fair, HSG C (A1, A2, B1a, B1b, B2a, C1, D1)
2.791 98 Paved parking, HSG C (D1)
14.058 95 TOTAL AREA
City Council Agenda November 7, 2023
2022_Ardmore
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 4 Soil Listing (all nodes)
Area
(acres)
Soil
Group
Subcatchment
Numbers
0.000 HSG A
0.000 HSG B
14.058 HSG C A1, A2, B1a, B1b, B2a, C1, C2, D1
0.000 HSG D
0.000 Other
14.058 TOTAL AREA
City Council Agenda November 7, 2023
2022_Ardmore
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 5 Ground Covers (all nodes)
HSG-A
(acres)
HSG-B
(acres)
HSG-C
(acres)
HSG-D
(acres)
Other
(acres)
Total
(acres)
Ground
Cover
Subcatc
Number
0.000 0.000 8.728 0.000 0.000 8.728 Impervious
0.000 0.000 2.540 0.000 0.000 2.540 Landscaped, 50-75% Grass cover, Fair
0.000 0.000 2.791 0.000 0.000 2.791 Paved parking
0.000 0.000 14.058 0.000 0.000 14.058 TOTAL AREA
City Council Agenda November 7, 2023
2022_Ardmore
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 6 Pipe Listing (all nodes)
Line# Node
Number
In-Invert
(feet)
Out-Invert
(feet)
Length
(feet)
Slope
(ft/ft)
n Width
(inches)
Diam/Height
(inches)
Inside-Fill
(inches)
1 LID A1 819.00 818.50 35.0 0.0143 0.012 0.0 18.0 0.0
2 LID B1a 822.63 822.50 50.0 0.0026 0.012 0.0 18.0 0.0
3 LID B2a 822.19 821.89 30.0 0.0100 0.012 0.0 18.0 0.0
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 7 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SBUH method, Split Pervious/Imperv.
Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Link A: Outlet A Inflow=8.79 cfs 1.613 af
Primary=8.79 cfs 1.613 af
Link B: Outlet B Inflow=1.65 cfs 0.371 af
Primary=1.65 cfs 0.371 af
Link C: Outlet C Inflow=0.15 cfs 0.019 af
Primary=0.15 cfs 0.019 af
Link D: Outlet D Inflow=1.37 cfs 0.601 af
Primary=1.37 cfs 0.601 af
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 8 Summary for Link A: Outlet A
Inflow Area = 7.196 ac, 86.00% Impervious, Inflow Depth = 2.69" for 25-YR event Inflow = 8.79 cfs @ 10.13 hrs, Volume= 1.613 af
Primary = 8.79 cfs @ 10.13 hrs, Volume= 1.613 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link A: Outlet A
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
9 8
7 6
5 4
3 2
1 0
Inflow Area=7.196 ac
8.79 cfs
8.79 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 9 Summary for Link B: Outlet B
Inflow Area = 2.798 ac, 83.10% Impervious, Inflow Depth = 1.59" for 25-YR event Inflow = 1.65 cfs @ 10.10 hrs, Volume= 0.371 af
Primary = 1.65 cfs @ 10.10 hrs, Volume= 0.371 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link B: Outlet B
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
1 0
Inflow Area=2.798 ac
1.65 cfs
1.65 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 10 Summary for Link C: Outlet C
Inflow Area = 0.274 ac, 77.95% Impervious, Inflow Depth = 0.83" for 25-YR event Inflow = 0.15 cfs @ 9.94 hrs, Volume= 0.019 af
Primary = 0.15 cfs @ 9.94 hrs, Volume= 0.019 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link C: Outlet C
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
0.17 0.16
0.15 0.14
0.13 0.12
0.11 0.1
0.09 0.08
0.07 0.06
0.05 0.04
0.03 0.02
0.01 0
Inflow Area=0.274 ac
0.15 cfs
0.15 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 25-YR Rainfall=4.70"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 11 Summary for Link D: Outlet D
Inflow Area = 3.790 ac, 73.64% Impervious, Inflow Depth = 1.90" for 25-YR event Inflow = 1.37 cfs @ 10.79 hrs, Volume= 0.601 af
Primary = 1.37 cfs @ 10.79 hrs, Volume= 0.601 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link D: Outlet D
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
1 0
Inflow Area=3.790 ac
1.37 cfs
1.37 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 12 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SBUH method, Split Pervious/Imperv.
Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Link A: Outlet A Inflow=11.25 cfs 2.003 af
Primary=11.25 cfs 2.003 af
Link B: Outlet B Inflow=2.53 cfs 0.527 af
Primary=2.53 cfs 0.527 af
Link C: Outlet C Inflow=0.18 cfs 0.022 af
Primary=0.18 cfs 0.022 af
Link D: Outlet D Inflow=3.36 cfs 0.819 af
Primary=3.36 cfs 0.819 af
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 13 Summary for Link A: Outlet A
Inflow Area = 7.196 ac, 86.00% Impervious, Inflow Depth = 3.34" for 50-YR event Inflow = 11.25 cfs @ 10.08 hrs, Volume= 2.003 af
Primary = 11.25 cfs @ 10.08 hrs, Volume= 2.003 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link A: Outlet A
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
12 11
10 9
8 7
6 5
4 3
2 1
0 Inflow Area=7.196 ac
11.25 cfs
11.25 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 14 Summary for Link B: Outlet B
Inflow Area = 2.798 ac, 83.10% Impervious, Inflow Depth = 2.26" for 50-YR event Inflow = 2.53 cfs @ 10.05 hrs, Volume= 0.527 af
Primary = 2.53 cfs @ 10.05 hrs, Volume= 0.527 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link B: Outlet B
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
2 1
0 Inflow Area=2.798 ac
2.53 cfs
2.53 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 15 Summary for Link C: Outlet C
Inflow Area = 0.274 ac, 77.95% Impervious, Inflow Depth = 0.96" for 50-YR event Inflow = 0.18 cfs @ 9.94 hrs, Volume= 0.022 af
Primary = 0.18 cfs @ 9.94 hrs, Volume= 0.022 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link C: Outlet C
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
0.19 0.18
0.17 0.16
0.15 0.14
0.13 0.12
0.11 0.1
0.09 0.08
0.07 0.06
0.05 0.04
0.03 0.02
0.01 0
Inflow Area=0.274 ac
0.18 cfs
0.18 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 50-YR Rainfall=5.42"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 16 Summary for Link D: Outlet D
Inflow Area = 3.790 ac, 73.64% Impervious, Inflow Depth = 2.59" for 50-YR event Inflow = 3.36 cfs @ 10.26 hrs, Volume= 0.819 af
Primary = 3.36 cfs @ 10.26 hrs, Volume= 0.819 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link D: Outlet D
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
3 2
1 0
Inflow Area=3.790 ac
3.36 cfs
3.36 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 17 Time span=0.00-72.00 hrs, dt=0.01 hrs, 7201 points
Runoff by SBUH method, Split Pervious/Imperv.
Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Link A: Outlet A Inflow=13.51 cfs 2.409 af
Primary=13.51 cfs 2.409 af
Link B: Outlet B Inflow=3.42 cfs 0.690 af
Primary=3.42 cfs 0.690 af
Link C: Outlet C Inflow=0.20 cfs 0.026 af
Primary=0.20 cfs 0.026 af
Link D: Outlet D Inflow=6.81 cfs 1.045 af
Primary=6.81 cfs 1.045 af
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 18 Summary for Link A: Outlet A
Inflow Area = 7.196 ac, 86.00% Impervious, Inflow Depth = 4.02" for 100-YR event Inflow = 13.51 cfs @ 10.05 hrs, Volume= 2.409 af
Primary = 13.51 cfs @ 10.05 hrs, Volume= 2.409 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link A: Outlet A
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
15 14
13 12
11 10
9 8
7 6
5 4
3 2
1 0
Inflow Area=7.196 ac
13.51 cfs
13.51 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 19 Summary for Link B: Outlet B
Inflow Area = 2.798 ac, 83.10% Impervious, Inflow Depth = 2.96" for 100-YR event Inflow = 3.42 cfs @ 10.07 hrs, Volume= 0.690 af
Primary = 3.42 cfs @ 10.07 hrs, Volume= 0.690 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link B: Outlet B
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
3 2
1 0
Inflow Area=2.798 ac
3.42 cfs
3.42 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 20 Summary for Link C: Outlet C
Inflow Area = 0.274 ac, 77.95% Impervious, Inflow Depth = 1.13" for 100-YR event Inflow = 0.20 cfs @ 9.94 hrs, Volume= 0.026 af
Primary = 0.20 cfs @ 9.94 hrs, Volume= 0.026 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link C: Outlet C
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
0.22 0.21
0.2 0.19
0.18 0.17
0.16 0.15
0.14 0.13
0.12 0.11
0.1 0.09
0.08 0.07
0.06 0.05
0.04 0.03
0.02 0.01
0 Inflow Area=0.274 ac
0.20 cfs
0.20 cfs
City Council Agenda November 7, 2023
2022_Ardmore Type I 24-hr 100-YR Rainfall=6.16"
Prepared by Wallace Group Printed 2/14/2023
HydroCAD® 10.20-2f s/n 05444 © 2022 HydroCAD Software Solutions LLC Page 21 Summary for Link D: Outlet D
Inflow Area = 3.790 ac, 73.64% Impervious, Inflow Depth = 3.31" for 100-YR event Inflow = 6.81 cfs @ 10.10 hrs, Volume= 1.045 af
Primary = 6.81 cfs @ 10.10 hrs, Volume= 1.045 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-72.00 hrs, dt= 0.01 hrs Link D: Outlet D
Inflow
Primary
Hydrograph
Time (hours)
727068666462605856545250484644424038363432302826242220181614121086420 Flow (cfs)
7 6
5 4
3 2
1 0
Inflow Area=3.790 ac
6.81 cfs
6.81 cfs
City Council Agenda November 7, 2023
City Council Agenda November 7, 2023
HY-8 Culvert Analysis Report
Crossing Discharge Data
Discharge Selection Method: Specify Minimum, Design, and Maximum Flow Minimum Flow: 1 cfs
Design Flow: 62.54 cfs
Maximum Flow: 76.97 cfs
BYPASS CULVERT
City Council Agenda November 7, 2023
Tailwater
Elevation = 823.35' BYPASS CULVERT
City Council Agenda November 7, 2023
Property Line
BYPASS CULVERT
City Council Agenda November 7, 2023
Table 1 - Summary of Culvert Flows at Crossing: Ardmore Double Culvert Headwater Elevation
(ft)
Total Discharge (cfs) Double 36 Discharge
(cfs)
Roadway Discharge
(cfs)
Iterations
823.30 1.00 1.00 0.00 1
823.33 8.60 8.60 0.00 1
823.39 16.19 16.19 0.00 1
823.49 23.79 23.79 0.00 1
823.63 31.39 31.37 0.04 4
823.79 38.98 38.69 0.29 4
823.96 46.58 45.60 0.97 5
824.13 54.18 51.58 2.58 5
824.29 61.78 57.02 4.72 5
824.31 62.54 57.52 4.96 3
824.57 76.97 66.72 10.21 5
823.50 24.45 24.45 0.00 Overtopping
BYPASS CULVERT
City Council Agenda November 7, 2023
Table 2 - Culvert Summary Table: Double 36
Total
Discharge
(cfs)
Culvert
Discharge
(cfs)
Headwater
Elevation (ft)
Inlet Control
Depth (ft)
Outlet
Control
Depth (ft)
Flow
Type
Normal
Depth (ft)
Critical
Depth (ft)
Outlet Depth
(ft)
Tailwater
Depth (ft)
Outlet
Velocity
(ft/s)
Tailwater
Velocity
(ft/s)
1.00 1.00 823.30 0.292 1.760 1-S1f 0.197 0.214 3.000 3.200 0.071 0.000
8.60 8.60 823.33 0.882 1.785 1-S1f 0.563 0.644 3.000 3.200 0.608 0.000
16.19 16.19 823.39 1.230 1.848 1-S1f 0.774 0.892 3.000 3.200 1.145 0.000
23.79 23.79 823.49 1.512 1.949 1-S1f 0.944 1.090 3.000 3.200 1.683 0.000
31.39 31.37 823.63 1.802 2.085 1-S1f 1.093 1.261 3.000 3.200 2.219 0.000
38.98 38.69 823.79 2.052 2.248 1-S1f 1.225 1.411 3.000 3.200 2.737 0.000
46.58 45.60 823.96 2.270 2.424 1-S1f 1.344 1.536 3.000 3.200 3.225 0.000
54.18 51.58 824.13 2.448 2.592 1-S1f 1.443 1.635 3.000 3.200 3.649 0.000
61.78 57.02 824.29 2.607 2.751 1-S1f 1.532 1.724 3.000 3.200 4.034 0.000
62.54 57.52 824.31 2.621 2.765 1-S1f 1.540 1.732 3.000 3.200 4.068 0.000
76.97 66.72 824.57 2.889 3.032 1-S1f 1.688 1.872 3.000 3.200 4.719 0.000
BYPASS CULVERT
City Council Agenda November 7, 2023
******************************************************************************** Straight Culvert
Inlet Elevation (invert): 821.54 ft, Outlet Elevation (invert): 820.10 ft Culvert Length: 271.67 ft, Culvert Slope: 0.0053
******************************************************************************** Site Data - Double 36
Site Data Option: Culvert Invert Data
Inlet Station: 0.00 ft
Inlet Elevation: 821.54 ft
Outlet Station: 271.67 ft
Outlet Elevation: 820.10 ft
Number of Barrels: 2
Culvert Data Summary - Double 36
Barrel Shape: Circular
Barrel Diameter: 3.00 ft
Barrel Material: Smooth HDPE
Embedment: 0.00 in
Barrel Manning's n: 0.0120
Culvert Type: Straight
Inlet Configuration: Square Edge with Headwall
Inlet Depression: None
BYPASS CULVERT
City Council Agenda November 7, 2023
Table 3 - Downstream Channel Rating Curve (Crossing: Ardmore Double Culvert) Flow (cfs) Water Surface Elev (ft) Depth (ft)
1.00 823.30 3.20
8.60 823.30 3.20
16.19 823.30 3.20
23.79 823.30 3.20
31.39 823.30 3.20
38.98 823.30 3.20
46.58 823.30 3.20
54.18 823.30 3.20
61.78 823.30 3.20
62.54 823.30 3.20
76.97 823.30 3.20
BYPASS CULVERT
City Council Agenda November 7, 2023
Tailwater Channel Data - Ardmore Double Culvert
Tailwater Channel Option: Enter Constant Tailwater Elevation Constant Tailwater Elevation: 823.30 ft
Roadway Data for Crossing: Ardmore Double Culvert
Roadway Profile Shape: Irregular Roadway Shape (coordinates) Roadway Surface: Gravel
Roadway Top Width: 2.00 ft
BYPASS CULVERT
City Council Agenda November 7, 2023
SAFE OVERLAND ESCAPE PATH ANALYSIS
FOR BYPASS CULVERT
City Council Agenda November 7, 2023
OFFSITE RUN-ON
FLOW PATH
OFFSITE RUN-ONOVERLAND ESCAPECROSS-SECTION
100-Year Storm -- Cross Section for Offsite Run-on OVE (crest) Project Description
Manning
Formula Friction Method
Solve For Normal Depth
Input Data
Channel Slope %1.00
Normal Depth ft1.96
Discharge cfs76.97
27 Siemon Company Drive Suite 200 W Page 1 of 1
Watertown, CT 06795 USA +1-203-755-1666
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FlowMaster
[10.03.00.03]
Bentley Systems, Inc. Haestad Methods Solution
2023-02-16_Ardmore_Misc SD.fm8 Center
City Council Agenda November 7, 2023
100-Year Storm -- Offsite Run-on OVE (crest)
Project Description
Manning
Formula Friction Method
Solve For Normal Depth
Input Data
Channel Slope %1.00
Discharge cfs76.97
Section Definitions
Elevation
(ft)
Station
(ft)
0+00 827.64
0+01 828.06
0+02 828.00
0+05 827.00
0+08 826.00
0+10 825.00
0+13 824.00
0+15 823.50
0+16 824.00
0+22 825.00
0+43 826.00
Roughness Segment Definitions
Start Station Ending Station Roughness Coefficient
(0+00, 827.64) (0+02, 828.00) 0.013
(0+02, 828.00) (0+43, 826.00) 0.025
Options
Pavlovskii's
Method
Current Roughness Weighted
Method
Pavlovskii's
Method
Open Channel Weighting
Method
Pavlovskii's
Method
Closed Channel Weighting
Method
Results
Normal Depth ft1.96
Roughness Coefficient 0.025
Elevation ft825.46
823.50 to
828.06 ft Elevation Range
Flow Area ft²16.3
Wetted Perimeter ft22.86
Hydraulic Radius ft0.71
Top Width ft22.34
Normal Depth ft1.96
27 Siemon Company Drive Suite 200 W Page 1 of 2
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City Council Agenda November 7, 2023
100-Year Storm -- Offsite Run-on OVE (crest)
Results
Critical Depth ft1.95
Critical Slope %1.05
Velocity ft/s4.73
Velocity Head ft0.35
Specific Energy ft2.31
Froude Number 0.979
Flow Type Subcritical
GVF Input Data
Downstream Depth ft0.00
Length ft0.00
Number Of Steps 0
GVF Output Data
Upstream Depth ft0.00
Profile Description N/A
Profile Headloss ft0.00
Downstream Velocity ft/sInfinity
Upstream Velocity ft/sInfinity
Normal Depth ft1.96
Critical Depth ft1.95
Channel Slope %1.00
Critical Slope %1.05
27 Siemon Company Drive Suite 200 W Page 2 of 2
Watertown, CT 06795 USA +1-203-755-1666
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City Council Agenda November 7, 2023
APPENDIX D
Appendix D – Preliminary Storm Drain Facility Concepts
• ADS StormTech MC-3500 Chamber overview
• Roadside Bioretention concept
City Council Agenda November 7, 2023
® ARDMORE - L.I.D. CONCEPT
TYPICAL ROADSIDE BIOSWALES WITH GRAVEL TRENCH
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DATE: 11/08/2022
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City Council Agenda November 7, 2023
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City Council Agenda November 7, 2023
(805) 316-0101
895 Napa Avenue, Suite A-6, Morro Bay, CA 93442
MEMORANDUM
Date: December 7, 2022
To: David Athey and Darren Nash, City of Paso Robles
From: Michelle Matson and Joe Fernandez, CCTC
Subject: Ardmore Industrial, Paso Robles –Transportation Analysis This memorandum summarizes the transportation impact analysis for the proposed Ardmore Industrial development at 2930 Union Road in the City of Paso Robles. The proposed project would construct 250,082 square feet of potential warehouse, office, winemaking, storage, and retail uses. The project site plan is included as Figure 1.
TRANSPORTATION ANALYSIS SUMMARY
The proposed project would generate approximately 1,194 net new vehicle trips per weekday, including 117 AM peak hour trips and 158 PM peak hour trips. The project would not significantly impact intersection operations and would have a less than significant impact on vehicle miles traveled (VMT).
The Golden Hill Road/Union Road roundabout project could consider restriping the left turn lane just south of Ardmore Road to a two-way left turn lane. We also recommend the following:
• Install all-way stop control at the Ardmore Road/Ardmore Road Extension t-intersection. • Consider consolidating the two central driveways on the existing Ardmore Road and placing the new driveway opposite the existing driveway location on the west side. Alternatively, remove the second northernmost driveway which has potential left turn conflicts with the existing driveway location on the west side.
• The Building 1 western driveway does not meet City standards. Relocate the proposed truck access for Building 1 so it is at least 200 feet away from the Ardmore Road/Ardmore Extension intersection.
Alternatively, this driveway could be one-way inbound forcing trucks to circulate through the parking lot and exit at the easternmost driveway.
• Add ADA parking spaces on the Ardmore Road extension and consider replacing parking tees with edge line striping.
• Install edge line striping on Ardmore Road along the project frontage. • Install no parking within the Ardmore Road intersection and 25 feet from each curb return and install no parking 6 feet from the curb return on either side of driveways.
Regional improvements are included in the City’s Development Impact Fees.
City Council Agenda November 7, 2023
December 2022 Source
City Council Agenda November 7, 2023
Ardmore Industrial, Paso Robles – Transportation Analysis 3 Central Coast Transportation Consulting December 7, 2022
CEQA ANALYSIS
Vehicle miles traveled (VMT) were analyzed consistent with recently mandated changes to the California Environmental Quality Act (CEQA) and state Office of Planning and Research (OPR) guidance. The City’s 2022 Transportation Impact Analysis (TIA) Guidelines Supplement provide VMT and safety thresholds consistent with OPR guidance. Office and industrial projects may have a significant impact if the work VMT per employee exceeds 85 percent of the regional average. Work VMT captures home-based-work attractions (trips from homes to workplaces). In addition, projects may have a significant impact if they exacerbate an existing high-priority or similar safety location, introduces a design feature that substantially increases hazards, or propose features that do not meet City design standards. Caltrans relies on VMT and safety to evaluate transportation impacts and published a VMT Focused TIS Guide in May 2020, which replaced the prior guide reliant on LOS. The TIS Guide notes that lead agencies have the discretion to choose VMT thresholds and methods, and generally conforms to OPR guidance.
The SLOCOG Travel Demand Model was applied to estimate VMT. Project employees were estimated using typical square footage per employee from industry standard sources, then were added to the model. Table 1 summarizes the VMT results.
Table 1: Regional VMT Analysis
The addition of the project would reduce regional work VMT due to the provision of jobs in a housing-rich area. Therefore, the project would have a less-than-significant impact to VMT.
Scenario
Regional
Employees
Regional
Work VMT
2020 No Project 117,332 1,595,867
2020 With Project 117,537 1,593,552
Change from No Project 205 -2,315
Source: SLOCOG TDM, CCTC, 2022
Regional VMT Analysis
1. Work VMT is attracted to workplaces (sum of home-basedwork attractions).
City Council Agenda November 7, 2023
Ardmore Industrial, Paso Robles – Transportation Analysis 4 Central Coast Transportation Consulting December 7, 2022
PROJECT TRIP GENERATION
The Institute of Transportation Engineers’ (ITE) Trip Generation Manual 11th Edition was used to estimate project trip generation. Table 2 summarizes the project trip generation.
Table 2: Project Trip Generation
The proposed project would generate 1,194 net new vehicle trips per weekday, including 117 AM peak hour trips and 158 PM peak hour trips.
TRANSPORTATION ANALYSIS
The following section summarizes the existing conditions, existing Ardmore Road trip generation, intersection operations, and site access and circulation.
Existing Conditions
Ardmore Road is a two-lane minor road with a 30 miles per hour (MPH) posted speed limit and intermittent sidewalks on either side of the roadway. Streetside parking is allowed intermittently along either side of the roadway.
Traffic collision data was obtained from the Statewide Integrated Traffic Records System (SWITRS). Between 2017 and 2021, no collisions occurred on Ardmore Road. One property damage only collision occurred just south of the Golden Hill Road/Ardmore Road intersection when a northbound driver sideswiped another vehicle and ran off the road due to unsafe speed. No other collisions occurred at the Golden Hill Road/Ardmore Road intersection. There are no collision patterns and no recommendations.
Currently, the Golden Hill Road/Union Road intersection is closed for the construction of a single lane roundabout through 2023. Traffic counts at the Golden Hill Road/Union Road intersection were collected in June and July of 2021 and are attached. No traffic counts are available on Ardmore Drive and new data was not collected due to the current detour on Ardmore Road.
Existing Ardmore Road Trip Generation
There is approximately 100,000 square feet of industrial uses and seven single family homes currently on Ardmore Road. The Institute of Transportation Engineers’ (ITE) Trip Generation Manual 11th Edition was also Daily
Total In Out Total In Out Total
Warehouse¹ 166.083 KSF 301 34 10 44 13 33 46
Manufacturing² 76.607 KSF 491 42 14 56 15 34 49
Retail³ 7.392 KSF 402 10 7 17 31 32 63
1,194 86 31 117 59 99 158
2. ITE Land Use Code #140, Manufacturing. Fitted curve equations used.
3. ITE Land Use Code #822, Strip Retail Plaza. Average rates used for Daily and AM. Fitted curve equation used for PM.
Size Unit
Total Project Trips
KSF = Thousand Square Feet; ITE = Institute of Transportation Engineers.
1. ITE Land Use Code #150, Warehouse. Fitted curve equations used.
AM Peak Hour PM Peak Hour
Ardmore Industrial Trip Generation
Land Use
City Council Agenda November 7, 2023
Ardmore Industrial, Paso Robles – Transportation Analysis 5 Central Coast Transportation Consulting December 7, 2022 used to estimate the existing trip generation on Ardmore Road. Table 3 summarizes the trip generation estimate for the existing uses on Ardmore Road.
Table 3: Existing Ardmore Road Trip Generation
The existing uses would generate 513 net new vehicle trips per weekday, including 79 AM peak hour trips and 48 PM peak hour trips. Following completion of the Golden Hill Road/Union Road roundabout, Ardmore Road will not be the fastest route and cut through traffic is not anticipated.
Intersection Operations
The 2021 traffic counts at Golden Hill/Union Road were used to develop through volumes on Golden Hill Road north of Ardmore Road and the existing Ardmore Road trip generation was used to estimate the turning movement volumes at Ardmore Road without the detour. Project trips were then added to develop Existing Plus Project Conditions. The Existing Plus Project volumes are shown on Figure 2 and the intersection operations are shown on Table 4. Detailed calculation sheets are attached.
Table 4: Existing Plus Project Intersection Operations
Both the Golden Hill Road/Union Road (#1) and Golden Hill/Ardmore Road (#2) intersections would operate at LOS C or better with the addition of project traffic and the completion of the Golden Hill Road/Union Road (#1) roundabout. No queues exceed the available storage.
In Out Total In Out Total
General Light Industrial 100.000 KSF 426 63 9 72 5 35 40 Single Family Home 7.000 DU 87 2 5 7 5 3 8
513 65 14 79 10 38 48
1. ITE Land Use Code #110, General Light Industrial. Fitted curve equations used.
2. ITE Land Use Code #210, Single Family Detached Housing. Fitted curve equations used.
Land Use Size Unit
Daily
Total
Existing Ardmore Road Trip Generation
AM Peak Hour PM Peak Hour
Total Gross Vehicle Trips
KSF = Thousand Square Feet; ITE = Institute of Transportation Engineers, DU = Dwelling Unit Intersection Weekday
Peak Hour Delay1 LOS
AM 10.0 A
PM 10.9 B
AM 1.6 (18.6) - (C)
PM 2.7 (23.4) - (C)
Existing Plus Project Intersection Operations
1. HCM 6th average control delay in seconds per vehicle. For two-way stop controlled (TWSC) intersections the worst approach's delay is reported in parentheses next to the overall delay.
1. Golden Hill Rd/Union Rd
2. Golden Hill Rd/Ardmore Rd Page 1008 of 1329
City Council Agenda November 7, 2023
December 2022 December 2022
City Council Agenda November 7, 2023
Ardmore Industrial, Paso Robles – Transportation Analysis 7 Central Coast Transportation Consulting December 7, 2022 Exhibit 1 below shows the proposed intersection striping at Golden Hill Road/Ardmore Road (#2) following completion of the roundabout.
Exhibit 1: Golden Hill Road/Ardmore Road Intersection Striping The Ardmore Road stop bar is located east of the existing curb ramp to allow for pedestrian travel. Therefore, drivers on Ardmore Road need to stop at the stop bar and then creep toward Golden Hill Road prior to making a turning movement. The intersection analysis did not include two-stage gap acceptance; however, the Golden Hill Road/Union Road roundabout project could consider restriping the left turn lane just south of Ardmore Road to a two-way left turn lane to allow for two-stage gap acceptance, which would improve operations.
Site Access and On-Site Circulation
The current site is vacant. The project proposes four driveways on Ardmore Road. The project proposes a main driveway extending Ardmore Road to the east, creating a t-intersection. The project also proposes three additional driveways along Ardmore Road north of the extension, a minimum of 200 feet apart. However, there is an existing intersection on the west side of the road approximately 300 feet north of Ardmore Road.
We recommend the project install all-way stop control at the Ardmore Road/Ardmore Road Extension tintersection to control left turn conflicts. We also recommend consolidating the two central driveways on the existing Ardmore Road and placing the new driveway opposite the existing driveway location on the west side.
Alternatively, remove the second northernmost driveway which has potential left turn conflicts with the existing driveway location on the west side.
The primary truck access point for Building 1 is proposed on the Ardmore Road extension just east of the existing Ardmore Road. The driveway does not meet City Standard Drawing C-10 and the truck turning movements as shown on the site plan are not recommended in this location. 200-foot minimum driveway spacing is recommended. We recommend the project relocate the proposed truck access or convert to one-way inbound.
City Council Agenda November 7, 2023
Ardmore Industrial, Paso Robles – Transportation Analysis 8 Central Coast Transportation Consulting December 7, 2022 Americans with Disabilities Act (ADA) parking spaces are recommended on the Ardmore Road extension.
Edge line striping could also be considered as an alternative to the parking tees.
Street features including landscaping, utility poles, street furniture, signs, and parked vehicles can inhibit sight distance in urban areas. Per California Manual on Uniform Traffic Control Devices (CAMUTCD) guidance, “At all intersections, one stall length on each side measured from the crosswalk or end of curb return should have parking prohibited. A clearance of 6 feet measured from the curb return should be provided at alleys and driveways.” We recommend parking restriction consistent with the CAMUTCD.
ATTACHMENTS
Traffic Count
Synchro Worksheets
REFERENCES
California Department of Transportation. May 2020. Vehicle Miles Traveled-Focused Transportation Impact Study Guide.
_____. 2012, 2018. Highway Design Manual.
_____. 2014, Revision 6. California Manual on Uniform Traffic Control Devices.
City of El Paso De Robles. 2017. Bicycle & Pedestrian Master Plan. _____. 2018. General Plan Circulation Element.
_____. 2013. Transportation Impact Analysis Guidelines. _____. 2022. Transportation Impact Analysis Guidelines Supplement.
Institute of Transportation Engineers (ITE). 2021. Trip Generation Manual, 11th Edition. _____. 2017. Trip Generation Handbook, 3rd Edition. ‘
The Natelson Company, Inc. 2001. Employment Density Study Summary Report.
Transportation Research Board. 2017. Highway Capacity Manual, 6th Edition.
City Council Agenda November 7, 2023
4 5 d B A c o u s t i c s , L L C
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This report (including any enclosures and attachments) has been prepared for the exclusive use and benefit of the addressee(s) and solely for the purpose for which it is provided. No part of this report shall be reproduced, distributed, or communicated to any third party without written permission. We do not accept any liability if this report is used for an alternative purpose from which it is intended, nor to any third party.
March 8, 2023
45dB Project # 23002
Acoustical Analysis:
Commercial/Light Industry
Development
2930 Union Rd.
Paso Robles, CA 93446
Requested by:
Kirk Consulting
Attn: Ian McCarville
8830 Morro Rd.
Atascadero, CA 93422
Client/Owner:
Covelop
1135 Santa Rosa St., Ste #210
San Luis Obispo, CA 93401
Summary
45dB Acoustics (“45dB”) has reviewed the applicable noise-related regulations for the commercial and light industrial 6-building planned development at the above address in the City of Paso Robles. Residences exist to the immediate north and east of the project, and a residential development is planned for the vacant site located directly south of the project. Properties to the west are industrial/commercial land uses. All neighboring properties exist within the City of Paso Robles.
Existing daytime hourly noise levels due to road traffic noise, primarily from Highway 46, range up to 43 dBA at the north property line adjacent to an existing residence, as predicted from published traffic counts and the FHWA’s Traffic Noise Model implemented into SoundPLAN®, a 3D noise propagation software package.
The proposed project was modeled to analyze the potential noise impact on the neighboring land uses. Noise levels associated with the project are anticipated to comprise of the following: traffic noise associated with the increased traffic on Ardmore Road; traffic and parking activities of 994 passenger vehicles daily in the surrounding parking lots; truck traffic and loading of up to 80 semi-trucks daily at the loading docks on the west side of Building 1; truck traffic and loading of up to 60 medium delivery trucks daily at the loading dock and in the service/loading lane along the north side of Building 6; truck traffic and loading of up to 60 medium delivery trucks daily in the service/loading lane along the south side of Building 3; a total of 37 rooftop HVAC units on the six Project buildings, each modeled with a sound power level of 87 dBA rel 10-12 W (i.e., sound pressure level of 76 dBA rel 20µPa at 1-m). All site activities were assumed to occur during daytime hours between 7am and 7pm. No vehicle idling was included in the service/loading lanes near Buildings 3 and 6 or near the loading docks at Building 1.
Refrigerated trucks are not expected at the Project site and were not included as a noise source in the model.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page ii noise management : room acoustics : environmental impact www.45dB.com With the project in place and the above assumptions about site traffic and rooftop HVAC equipment, the modeled Daytime Hourly LAeq levels along the property lines adjacent to residential land uses ranged up to 55 dBA and Nighttime Hourly LAeq levels ranged up to 45 dBA, both of which comply with the Municipal Code Daytime limit of 55 dBA and Nighttime limit of 45 dBA for residential land uses.
for 45dB Acoustics, LLC:
Sarah Taubitz, Mem.INCE, ASA
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page iii noise management : room acoustics : environmental impact www.45dB.com Contents
Summary .......................................................................................................................................................................i 1 Introduction........................................................................................................................................................1 2 Regulatory Setting..............................................................................................................................................2
2.1 Local Regulation – City of Paso Robles Noise Ordinance..............................................................................2
2.1.1 Residential Exterior Ambient Noise Levels...........................................................................................2
2.1.2 Commercial/Industrial Exterior Ambient Noise Levels.........................................................................2 3 Noise Propagation Model ..................................................................................................................................4
3.1 Local Transportation Noise.............................................................................................................................4
3.2 Warehouse Shipping Activity...........................................................................................................................5
3.3 Service and Loading Lanes .............................................................................................................................5
3.4 Parking Areas..................................................................................................................................................6
3.5 HVAC Equipment ............................................................................................................................................6 4 Existing Site Ambient Noise Environment.......................................................................................................7 5 Predicted Future Noise Environment with Project.........................................................................................8
5.1 Assumptions and Limitations...........................................................................................................................9
5.1.1 Loading Areas........................................................................................................................................9
5.1.2 Parking Lots...........................................................................................................................................9
5.1.3 Rooftop HVAC Equipment .................................................................................................................10 6 Conclusion ........................................................................................................................................................11 7 Figures...............................................................................................................................................................12 8 Appendix...........................................................................................................................................................17
8.1 Characteristics of Sound ...............................................................................................................................17
8.2 Terminology/Glossary ...................................................................................................................................18
8.3 SoundPLAN Acoustics Software....................................................................................................................20
8.3.1 ISO 9613-2...........................................................................................................................................20
8.3.2 Traffic Noise Model.............................................................................................................................20
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page iv noise management : room acoustics : environmental impact www.45dB.com Figures
FIGURE 1: AERIAL MAP OF PROPOSED PROJECT SITE AND SURROUNDING PROPERTIES (GOOGLEMAPS) ...........................................12 FIGURE 2: PROJECT SITE PLAN (DATED 2-13-2023)...............................................................................................................13 FIGURE 3: DAYTIME (“LEQ,D”) SOUND LEVEL CONTOURS, EXISTING SITE ......................................................................................14 FIGURE 4: 3D VIEW OF SITE GEOMETRY, WITH PROPOSED PROJECT...........................................................................................15 FIGURE 5: DAYTIME (“LEQ,D”) SOUND LEVEL CONTOURS, WITH PROPOSED PROJECT ......................................................................16 Tables
TABLE 1: CITY OF PASO ROBLES NOISE ORDINANCE STANDARDS FOR NON-TRANSPORTATION NOISE SOURCES (REPRINT)......................3 TABLE 2: TRAFFIC COUNT DATA, 2023 ESTIMATES, AND PROJECTIONS DUE TO PROJECT..................................................................4 TABLE 3: SOUND LEVELS AT RECEIVERS OF INTEREST..................................................................................................................8 TABLE 4: SOUND LEVEL CHANGE RELATIVE LOUDNESS/ACOUSTIC ENERGY LOSS...........................................................................17
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 1 noise management : room acoustics : environmental impact www.45dB.com 1 Introduction
This sound level assessment and analysis was carried out to determine the noise impacts associated with the proposed mixed-use development at 2930 Union Rd in Paso Robles, CA. 45dB Acoustics, LLC (“45dB”) has predicted sound levels across the site and evaluated the project’s suitability in reference to local regulations. Neighboring properties—particularly the existing residence to the immediate north and future residential developments to the immediate south—have been considered. The following factors are also considered:
• The topographical relationship of potential noise sources and applicable noise ordinances/laws
• Identification of noise sources and their characteristics, including predicted noise levels at representative neighboring receiver location(s), considering present and future land usage • Basis for the sound level prediction (i.e., engineering inputs and assumptions) • Noise attenuation measures (mitigation) to be applied, if needed • Information on fundamentals of noise and vibration to aid in interpreting the report (Section 8, Appendix)
The project would consist of six new commercial/light industrial buildings located in the City of Paso Robles. Anticipated uses included warehousing / storage, wine processing and tasting, light /craft manufacturing, office, and limited retail. Residences and farmland are located immediately north and east of the project’s property lines (Figure 1). A residential development is planned to the immediate south. Commercial and industrial properties are located to the west of the project.
The project is planned to include 330 vehicle parking spaces and 17 motorcycle parking spaces.
A Transportation Impact Study was completed and is referenced herein for the increased traffic due to the project.
For the purposes of an acoustic study, with trucks in the loading areas as the dominant noise sources on site, the operating hours of 7am to 7pm (i.e. daytime hours) on weekdays were utilized for a conservative analysis. Most days and times of the year may have less traffic, and hence noise, emitting from the proposed project.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 2 noise management : room acoustics : environmental impact www.45dB.com 2 Regulatory Setting
Throughout this document, noise levels and limits are assumed to be A-weighted decibel levels.
2.1 Local Regulation – City of Paso Robles Noise Ordinance The project and all surrounding properties are located within Paso Robles. The City of Paso de Robles, CA Municipal Code Noise Ordinance1provides regulation and guidelines regarding noise. The Interior and Exterior Noise Standards (Table 1) define the limits due to locally regulated (non-transportation) noise sources at residential, industrial, and commercial receiving land uses.
2.1.1 Residential Exterior Ambient Noise Levels
The nearest potentially sensitive noise receptors evaluated in this study are the residential homes/dwellings—including those on agriculturally zoned land—at the locations indicated on Figure 1.
For residential uses, the limits are 55 dBA LAeq and 75 LAmax during daytime hours, 50 dBA LAeq and 70 LAmax during evening hours, and 45 dBA LAeq and 65 dBA LAmax during nighttime hours. Daytime hours are defined as 7am to 7pm, evening hours are 7pm to 10pm, and nighttime hours are 10pm – 7am. These limits are to be evaluated at the receiving land use property line.
2.1.2 Commercial/Industrial Exterior Ambient Noise Levels The nearest commercial/industrial properties are located directly west of the project, across Ardmore Rd. These land uses are highlighted in Figure 1.
For commercial and industrial land uses, The City of Paso Robles’ exterior noise standards for locally regulated noise sources are 60 dBA LAeq and 80 LAmax during daytime hours, and 55 dBA LAeq and 75 LAmax during evening hours (Table 1). Daytime hours are defined as 7am to 7pm and evening hours are 7pm to 10pm. Nighttime limits are not defined for these land uses because commercial and industrial properties are assumed to be unoccupied at night. 1 El Paso de Robles, California Municipal Code, Section 21.60.060, Interior and Exterior Noise Standards, 2019. https://library.municode.com/ca/el_paso_de_robles/codes/code_of_ordinances?nodeId=TIT21ZO_ARTVNO_CH21 .60NO_21.60.060EXINNOST
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 3 noise management : room acoustics : environmental impact www.45dB.com Table 1: City of Paso Robles Noise Ordinance Standards for Non-Transportation Noise Sources (reprint)
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 4 noise management : room acoustics : environmental impact www.45dB.com 3 Noise Propagation Model
SoundPLAN® is a state-of-the-art sound propagation modeling software package that calculates sound levels while taking into account the air and ground attenuation factors, terrain variation and the built environment, road pavement types, and other relevant factors. This software has incorporated many noise propagation standards, including the ISO 9613-2 and the FHWA’s Traffic Noise Model (TNM) calculation standards. More details about SoundPLAN®, TNM, and ISO 9613-2 can be found in Section 8.3.
Traffic counts for nearby roads are input to the model to establish an ambient existing noise environment. All sound pressure levels in this report are in units of A-weighted decibels (dBA) for direct comparison to the Code.
3.1 Local Transportation Noise
AADT (Annual Average Daily Traffic) counts are taken from the CalTrans traffic database2and the County of San Luis Obispo Traffic Engineering online database3and input directly into SoundPLAN®, which then distributes them across the day, evening, and nighttime periods to predict outdoor noise levels. Traffic counts are adjusted upward 1% per year to 2023.
Current traffic counts for Ardmore, Golden Hill, and Union Roads and their projected increases due to the Project were detailed in the transportation impact analysis4provided by the Client. The study provided peak AM and PM hourly counts which were used to estimate the current and projected AADT numbers used in the model. Of particular note, the average daily traffic on Ardmore is anticipated to increase by 1194, which includes passenger vehicles as well as the semi-trucks and medium delivery trucks that are anticipated to arrive daily at the Project site. 226 daily passenger and semi-truck trips are expected for Building 1 and 968 daily passenger and medium delivery truck trips are expected for Buildings 2-6.
Table 2: Traffic Count Data, 2023 Estimates, and Projections due to Project Road AADT Year
Years to
Project
2023 AADT
Projections
Projected AADT
Increase due to Project
Hwy 462 26500 2020 3 27303 --
Union Rd (E of Paso Robles)3 2985 2002 21 3679 --
Union Rd (Golden Hill to Paso
Robles)4
-- -- -- 8029 --
Union Rd (W of Golden Hill)4 -- -- -- 5389 215
2 CalTrans Traffic Census Program, 2020. https://dot.ca.gov/programs/traffic-operations/census 3 County of San Luis Obispo, Department of Public Works, Traffic Count Data, 2021. https://www.slocounty.ca.gov/Departments/Public-Works/Forms-Documents/Transportation/Traffic-Count-Data.pdf 4 Ardmore Industrial, Paso Robles –Transportation Analysis, Central Coast Transportation Consulting, December 2022.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 5 noise management : room acoustics : environmental impact www.45dB.com Road AADT Year
Years to
Project
2023 AADT
Projections
Projected AADT
Increase due to Project
Golden Hill (N of Union)4 -- -- -- 5785 358
Golden Hill (S of Union)4 -- -- -- 7445 539
Golden Hill (S of Ardmore)4 -- -- -- 7242 603
Ardmore (E of Golden Hill)4 -- -- -- 513 1194
All traffic was assumed to travel at a speed of 15 mph. All passenger, semi-truck, and delivery truck traffic was modeled for the hours between 7am and 7pm.
3.2 Warehouse Shipping Activity
The loading dock area on the west side of Building 1 (Figure 2) is expected to handle 80 semitrucks daily. These are input into the model with the following details:
• 80 heavy trucks per day, traveling at 10 mph between the hours of 7am and 7pm through the loading area and around Building 1
• Backup alarms for each semi-truck with an average sound power level (LWA) of 100 dBA and maximum sound power level (LWAmax) of 103 dBA, emitted for no longer than 15 seconds per vehicle in the loading area
• Air brakes for each semi-truck having a maximum sound power level (LWAmax) of 110 dBA, which would be emitted for no more than 2 seconds per vehicle in the loading area • We assumed that all vehicles would not idle for any significant amount of time • We assumed that no refrigerated trucks would be expected at this site. (Refrigerated semi-trailer trucks can be problematic for noise, as the refrigerator units for the containers tend to be high level, low-frequency tonal, may operate even when the truck is parked, and are located at a higher height toward the top of the truck containers.)
3.3 Service and Loading Lanes
Two service/loading areas are included on the project site, on the south side of Building 3 and on the north side of Building 6. These are input into the model with the following details:
• Each service lane would have no more than 60 cars and medium-sized delivery trucks, traveling at speeds of 10 mph or less between the hours of 7am and 7pm • A loading area on the northeast corner of Building 6, which includes a loading dock where delivery trucks may have a backup alarm. The backup alarms have an average sound power level (LAeq) of 100 dBA and maximum sound power level (LWAmax) of 103 dBA, which would be emitted for no longer than 10 seconds per vehicle at the loading dock
• We assumed that no medium truck or delivery vehicles would use air brakes • We assumed that all vehicles would not idle for any significant amount of time
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 6 noise management : room acoustics : environmental impact www.45dB.com For reference, a medium-duty truck typically has noise emission levels 5-7 dB lower than heavyduty semi-trucks.
3.4 Parking Areas
Parking areas surround the six Project site buildings. Modeled parking lot noise includes door slams and vehicle ignitions – and conservatively assumes all vehicles have internal-combustion engines. Per the Client, 186 daily vehicle trips are expected for Building 1 and 968 daily vehicle trips are expected for Buildings 2-6. With expected semi- and delivery truck traffic excluded, we modeled the parking area around Building 1 with parking activities for 146 passenger vehicles and the parking areas around Buildings 2-6 with activities for 848 passenger vehicles. All parking activities were assumed to only occur during daytime hours, between 7am and 7pm.
3.5 HVAC Equipment
Placement of the 37 rooftop HVAC units was provided by the architect on March 2, 2023. Nine (9) rooftop units (RTUs) were included for Building 1, two (2) RTUs on Building 2, six (6) RTUs on Building 3, six (6) RTUs on Building 4, eight (8) RTUs on Building 5, and 6 (6) RTUs on Building 6.
Although the models have not yet been selected, based upon our experience with this equipment and calculated sound levels that would comply with the Municipal Code at the property lines, we assumed each unit has a sound power level (“LWA”) of no more than 87 dBA rel 10-12 W, corresponding to a sound pressure level of 76 dBA rel 20µPa at a distance of 1 meter.
All HVAC equipment was assumed to be operating continuously, 24 hours per day, since although not typical, the project has the potential for all units to be running simultaneously.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 7 noise management : room acoustics : environmental impact www.45dB.com 4 Existing Site Ambient Noise Environment
A 3D geometric model of the situation is created within the SoundPLAN® noise modeling software. Buildings and main roads are modeled on the terrain to create a realistic model of the outdoor noise propagation for the area.
All sound contour plots, in plan view, are presented at a height of 1.5 m / 5 feet (AGL) within this report, and all are in units of A-weighted dB rel 20µPa for direct comparison with the applicable regulations.
The Federal Highway Administration’s Traffic Noise Model (TNM) calculation method is utilized to predict outdoor noise propagation from the existing road traffic. Resulting daytime (“Leq,d”) sound level contours for the existing site are shown in Figure 3. Because these sound levels are calculated based only on road traffic, they are very low levels, particularly during evening and nighttime hours when traffic counts are lower. In reality, other sounds such as wind through vegetation, and other community sounds may contribute to and create levels higher than those shown here. In general, the areas further away from the roads are relatively quiet rural environments. For the residential use areas north of the project site on Ardmore Rd, daytime noise levels are approximately 42 dBA.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 8 noise management : room acoustics : environmental impact www.45dB.com 5 Predicted Future Noise Environment with Project
The 3D model with the project in place is shown in Figure 4. The resulting daytime sound level contours (at a 5-ft height) from the proposed Project and associated traffic, loading dock, and HVAC noise in place (as described in Section 3) are illustrated in Figure 5. The red asterisks (*) on each of the buildings represent the rooftop HVAC unit locations.
The daytime hourly levels at the residential property lines to the north, east, and south of the project site are not expected to exceed the Municipal Code residential Leq limit of 55 dBA.
Maximum daytime levels are also not expected to exceed the associated Lmax limit of 75 dBA.
Levels at the western commercial/industrial property lines are also not expected to exceed the Municipal Code limits.
Table 3 shows the existing ambient levels due to road traffic alone at selected property line receiver locations (shown in Figure 3 and Figure 5) as well as the anticipated effect the proposed Project would have at each location.
Table 3: Sound Levels at Receivers of Interest
Existing Ambient (Road Traffic Only) With Project
Receiver
CNEL /Ldn
(dBA)
Daytime
Hourly
Leq,d (dBA)
Evening
Hourly
Leq,e (dBA)
Nighttime
Hourly
Leq,n (dBA)
CNEL /Ldn
(dBA)
Daytime
Hourly
Leq,d (dBA)
Evening
Hourly†
Leq,e (dBA)
Nighttime
Hourly
Leq,n (dBA)
Daytime
Lmax
(dBA)
E1 42 41 36 34 52 51 45 44 44
E2 37 36 31 28 53 52 46 45 30
E3 38 37 32 29 49 47 41 41 32
N1 43 42 37 35 51 53 40 39 66
N2 42 41 36 34 53 55 39 38 71
NE 43 42 37 35 49 48 41 41 58
NW 43 43 37 34 53 54 44 42 52
S1 35 34 29 27 51 53 36 36 65
S2 34 33 28 26 45 46 36 35 52
SE 32 31 25 23 44 42 36 36 34
SW 36 35 30 27 51 53 37 36 64
W1* 35 35 29 26 57 60 40 39 66
W2* 35 34 29 26 57 60 39 38 76
* Receivers W1 & W2 are located on a property line shared with industrial/commercial land uses
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 9 noise management : room acoustics : environmental impact www.45dB.com All locations are expected to comply with the Municipal Code, assuming all site activities operate as described within this report and between 7am and 7pm. Although vehicle noise is not present at night, the HVAC units are often still running, which is responsible for a sizable increase during nighttime hours as shown. HVAC units typically run a fraction of any hour, so the increase shown is conservatively high and may be approximately 10dB lower on an hourly Leq basis. Rooftop units also can be screened to provide mitigation (not included here), and parapet walls may further redirect noise due to rooftop equipment.
5.1 Assumptions and Limitations
The sound level contours are provided for visualization purposes showing resulting sound levels during daytime hours. Daytime hourly sound levels are the primary metric used for evaluation since all Project site activities are expected to occur during daytime hours.
5.1.1 Loading Areas
The related maximum (“Lmax” or “LAmax”) limits within the regulations also apply while evaluating any proposed project. Maximum short-duration noises for this project include mainly the braking from semi-trucks and backup alarms from semi-trucks and medium delivery trucks in the loading areas outside Buildings 1 and 6. We anticipate that backup noises are within 20dB above the hourly LAeq levels from the trucking activities, such that if the hourly LAeq levels for the site comply, then the maximum levels for the site will also comply with the applicable regulations.
We assume trucks will not idle for long periods of time while parked. We recommend that any semi-trucks wishing to continuously idle do so near the north side of the Building 1 loading area, away from the property lines. If trucks run idle for the majority of a given hour, it can become a nuisance and potential code exceedance. The most effective mitigation is limiting/minimizing truck idling, which we presume is already the case. This is also true for backup beeping and truck air brakes usage.
Noise levels at the property lines are primarily limited by the number of semi-trucks and medium delivery trucks in the loading areas around Buildings 1 and 6. If more than 80 semi-trucks per day are expected in the loading area of Building 1, mitigation will be required at the south and west property lines due to the additional truck traffic noise in the loading area. Similarly, if more than 60 medium delivery trucks are anticipated to use the service/loading lane and dock north of Building 1, mitigation will be required.
5.1.2 Parking Lots
Parking areas surrounding the Project buildings were conservatively modeled with 994 passenger vehicles per day between the hours of 7am and 7pm. Further analysis would be required if parking activities were expected during evening or nighttime hours to ensure compliance with the Municipal Code.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 10 noise management : room acoustics : environmental impact www.45dB.com
5.1.3 Rooftop HVAC Equipment
Using the preliminary HVAC rooftop unit (RTU) layout provided by the architect, we included a maximum sound power level “LWA” of 87 dBA for each unit on the buildings as constant 24/7 noise sources in our model that would allow the Project to comply with the Municipal Code.
This HVAC noise can be considered “worst-case” for the project, and it contributes a significant portion of the total noise increase calculated.
Sound levels at the property lines can increase or decrease depending on the proximity of the RTUs. Nighttime levels along the east property line will not comply if the RTUs on Buildings 3 and 5 are placed closer than 100 feet from the east property line.
These units typically run less frequently at night and perhaps 25 to 50% of the daytime hours, so projected levels may be higher than typical during day and night hours. However, if the RTUs are louder than the sound power level “LWA” of 87 dBA, are located in significantly different locations than shown in the model, are placed closer to the property lines than indicated above, or if there will be more units on-site than included in this analysis, a revised analysis would be required to verify compliance. RTUs can also be screened/mitigated to reduce potential impact.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 11 noise management : room acoustics : environmental impact www.45dB.com 6 Conclusion
Existing daytime hourly noise levels due to road traffic noise, primarily from Highway 46, range up to 43 dBA at the north property line adjacent to an existing residence, as predicted from published traffic counts and the FHWA’s Traffic Noise Model implemented into SoundPLAN®.
The proposed project was modeled to analyze the potential noise impact on the neighboring land uses. Noise levels associated with the project are anticipated to comprise of the following:
• Traffic noise associated with the increased traffic on Ardmore Road • Traffic and parking activities of 994 passenger vehicles daily in the surrounding parking lots
• Truck traffic and loading of up to 80 semi-trucks daily at the loading docks on the west side of Building 1
• Truck traffic and loading of up to 60 medium delivery trucks daily at the loading dock and in the service/loading lane along the north side of Building 6 • Truck traffic and loading of up to 60 medium delivery trucks daily in the service/loading lane along the south side of Building 3
• 37 rooftop HVAC units on the six Project buildings, each modeled with a sound power level of 87 dBA rel 10-12 W (i.e., sound pressure level of 76 dBA rel 20µPa at 1-m). • All site activities were assumed to occur during daytime hours between 7am and 7pm • No vehicle idling was included for the service/loading lanes near Buildings 3 and 6 or near the loading docks at Building 1
• Refrigerated trucks are not expected at the Project site and were not included as a noise source in the model
With the project in place and the above assumptions about site traffic and rooftop HVAC equipment, the modeled Daytime Hourly LAeq levels along the property lines adjacent to residential land uses ranged up to 55 dBA and Nighttime Hourly LAeq levels ranged up to 45 dBA, both of which comply with the Municipal Code Daytime limit of 55 dBA and Nighttime limit of 45 dBA for residential land uses.
The conclusions and recommendations of this acoustical analysis are based upon the information known to 45dB Acoustics, LLC (“45dB”) at the time the analysis was prepared concerning the proposed site plans, traffic volumes, and proposed project activities. Any significant changes to these factors will require a reevaluation of the findings of this report. Additionally, any significant future changes in site plan, noise regulations, or other factors beyond 45dB’s control may result in long-term noise results that differ from those described by this analysis.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 12 noise management : room acoustics : environmental impact www.45dB.com 7 Figures
Figure 1: Aerial Map of Proposed Project Site and Surrounding Properties (GoogleMaps)
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 13 noise management : room acoustics : environmental impact www.45dB.com Figure 2: Project Site Plan (Dated 2-13-2023)
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 14 noise management : room acoustics : environmental impact www.45dB.com Figure 3: Daytime (“Leq,d”) Sound Level Contours, Existing Site
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 15 noise management : room acoustics : environmental impact www.45dB.com Figure 4: 3D View of Site Geometry, with Proposed Project
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 16 noise management : room acoustics : environmental impact www.45dB.com Figure 5: Daytime (“Leq,d”) Sound Level Contours, with Proposed Project
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 17 noise management : room acoustics : environmental impact www.45dB.com 8 Appendix
8.1 Characteristics of Sound
When an object vibrates, it radiates part of its energy as acoustical pressure in the form of a sound wave. Sound can be described in terms of amplitude (loudness), frequency (pitch), or duration (time). The human hearing system is not equally sensitive to sound at all frequencies.
Therefore, to approximate this human, frequency-dependent response, the A-weighted filter system is used to adjust measured sound levels. The normal range of human hearing extends from approximately 0 to 140 dBA. Unlike linear units such as inches or pounds, decibels are measured on a logarithmic scale, representing points on a sharply rising curve. Because of the physical characteristics of noise transmission and of noise perception, the relative loudness of sound does not closely match the actual amounts of sound energy. Table 4 below presents the subjective effect of changes in sound pressure levels.
Table 4: Sound Level Change Relative Loudness/Acoustic Energy Loss5 0 dBA Reference 0%
-3 dBA Barely Perceptible Change 50%
-5 dBA Readily Perceptible Change 67%
-10 dBA Half as Loud 90%
-20 dBA 1/4 as Loud 99%
-30 dBA 1/8 as Loud 99.9%
Sound levels are generated from a source and their decibel level decreases as the distance from that source increases. Sound dissipates exponentially with distance from the noise source. This phenomenon is known as spreading loss. Generally, sound levels from a point source will decrease by 6 dBA for each doubling of distance. Sound levels for a highway line source vary differently with distance because sound pressure waves propagate along the line and overlap at the point of measurement. A closely spaced, continuous line of vehicles along a roadway becomes a line source and produces a 3 dBA decrease in sound level for each doubling of distance. However, experimental evidence has shown that where sound from a highway propagates close to “soft” ground (e.g., plowed farmland, grass, crops, etc.), a more suitable drop-off rate to use is not 3.0 dBA but rather 4.5 dBA per distance doubling (FHWA 2010).
When sound is measured for distinct time intervals, the statistical distribution of the overall sound level during that period can be obtained. The Leq is the most common parameter associated with such measurements. The Leq metric is a single-number noise descriptor that represents the average sound level over a given period of time. For example, the L50 noise level is the level that is exceeded 50 percent of the time. This level is also the level that is exceeded 30 minutes in an hour. Similarly, the L02, L08 and L25 values are the noise levels that are exceeded 2, 8, and 25 percent of the time or 1, 5, and 15 minutes per hour. Other values typically noted during a 5 Highway Traffic Noise Analysis and Abatement Policy and Guidance, U.S. Department of Transportation, Federal Highway Administration, Office of Environment and Planning, Noise and Air Quality Branch, June 1995.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 18 noise management : room acoustics : environmental impact www.45dB.com noise survey are the Lmin and Lmax. These values represent the minimum and maximum rootmean-square noise levels obtained over the measurement period.
Because community receptors are more sensitive to unwanted noise intrusion during the evening and at night, State law requires that, for planning purposes, an artificial dB increment be added to quiet-time noise levels in a 24-hour noise descriptor called the CNEL or Ldn. This increment is incorporated in the calculation of CNEL or Ldn, described earlier.
8.2 Terminology/Glossary
A-Weighted Sound Level (dBA)
The sound pressure level in decibels as measured on a sound level meter using the internationally standardized A-weighting filter or as computed from sound spectral data to which A-weighting adjustments have been made. A-weighting de-emphasizes the low and very high frequency components of the sound in a manner similar to the response of the average human ear. Aweighted sound levels correlate well with subjective reactions of people to noise and are universally used for community noise evaluations.
Air-borne Sound
Sound that travels through the air, differentiated from structure-borne sound.
Ambient Sound Level
The prevailing general sound level existing at a location or in a space, which usually consists of a composite of sounds from many sources near and far. The ambient level is typically defined by the Leq level.
Background Sound Level
The underlying, ever-present lower level noise that remains in the absence of intrusive or intermittent sounds. Distant sources, such as Traffic, typically make up the background. The background level is generally defined by the L90 percentile noise level.
Community Noise Equivalent Level (CNEL)
The Leq of the A-weighted noise level over a 24-hour period with a 5-dB penalty applied to noise levels between 7 p.m. and 10 p.m. and a 10-dB penalty applied to noise levels between 10 p.m. and 7 a.m. CNEL is similar to Ldn.
Day-Night Sound Level (Ldn)
The Leq of the A-weighted noise level over a 24-hour period with a 10-dB penalty applied to noise levels between 10 p.m. and 7 a.m. Ldn is similar to CNEL.
Decibel (dB)
The decibel is a measure on a logarithmic scale of the magnitude of a particular quantity (such as sound pressure, sound power, sound intensity) with respect to a reference quantity.
DBA or dB(A)
A-weighted sound level. The ear does not respond equally to all frequencies and is less sensitive at low and high frequencies than it is at medium or speech range frequencies. Thus, to obtain a single number representing the sound level of a noise containing a wide range of frequencies in a manner representative of the ear’s response, it is necessary to reduce the effects of the low and
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 19 noise management : room acoustics : environmental impact www.45dB.com high frequencies with respect to the medium frequencies. The resultant sound level is said to be A-weighted, and the units are dBA. The A-weighted sound level is also called the noise level.
Energy Equivalent Level (Leq)
Because sound levels can vary markedly in intensity over a short period of time, some method for describing either the average character of the sound or the statistical behavior of the variations must be utilized. Most commonly, one describes ambient sounds in terms of an average level that has the same acoustical energy as the summation of all the time-varying events. This energy-equivalent sound/noise descriptor is called Leq. In this report, an hourly period is used.
Field Sound Transmission Class (FSTC)
A single number rating similar to STC, except that the transmission loss values used to derive the FSTC are measured in the field. All sound transmitted from the source room to the receiving room is assumed to be through the separating wall or floor-ceiling assembly.
Noise Reduction (NR)
Noise reduction is the difference between outdoor sound level and indoor sound level. It is not identical to Sound Transmission Class.
Outdoor-Indoor Transmission Class (OITC)
A single number classification, specified by the American Society for Testing and Materials (ASTM E1332 issued 1994), that establishes the A-weighted sound level reduction provided by building facade components (walls, doors, windows, and combinations thereof), based upon a reference sound spectrum that is an average of typical air, road, and rail transportation sources.
The OITC is the preferred rating when exterior façade components are exposed to a noise environment dominated by transportation sources. Once built, as much as a 5-point reduction in Apparent Outside-Inside Transmission Class (OITC) from the original, as-designed OITC may be expected.
Percentile Sound Level, Ln
The noise level exceeded during n percent of the measurement period, where n is a number between 0 and 100 (e.g., L10 or L90)
Sound Transmission Class (STC)
STC is a single number rating, specified by the American Society for Testing and Materials, which can be used to measure the sound insulation properties for comparing the sound transmission capability, in decibels, of interior building partitions for noise sources such as speech, radio, and television. It is used extensively for rating sound insulation characteristics of building materials and products.
Structure-Borne Sound
Sound propagating through building structure. Rapidly fluctuating elastic waves in gypsum board, joists, studs, etc.
Subjective Loudness Level
In addition to precision measurement of sound level changes, there is a subjective characteristic which describes how most people respond to sound:
• A change in sound level of 3 dBA is barely perceptible by most listeners. • A change in level of 6 dBA is clearly perceptible.
City Council Agenda November 7, 2023
45dB Acoustics, LLC 2930 Union Rd.
page 20 noise management : room acoustics : environmental impact www.45dB.com • A change of 10 dBA is perceived by most people as being twice (or half) as loud.
8.3 SoundPLAN Acoustics Software
SoundPLAN®, the software used for this acoustic analysis, is an acoustic ray-tracing program dedicated to the prediction of noise in the environment. Noise emitted by various sources propagates and disperses over a given terrain in accordance with the laws of physics. The software calculates sound attenuation of environmental noise, even over complex terrain, uneven ground conditions, and with complex obstacles. Up to three reflections for each noise source are taken into account to closely and accurately predict real-world acoustics. Worldwide, governments and engineering associations have created algorithms to calculate acoustical phenomena to standardize the assessment of physical scenarios. Accuracy has been validated in published studies to be + / - 2.7 dBA with an 85% confidence level.
8.3.1 ISO 9613-2
For industrial and other noise sources besides road traffic, SoundPLAN calculates the sound field in accordance with ISO 9613-2 “Acoustics - Attenuation of sound during propagation outdoors, Part 2: General Method of Calculation.” The standard states that “this part of ISO 9613 specifies an engineering method for calculating the attenuation of sound during propagation outdoors, in order to predict the levels of environmental noise at a distance from a variety of sources. The method predicts the equivalent continuous A-weighted sound pressure level under meteorological conditions favorable to propagation from sources of known sound emissions.
These conditions are for downwind propagation under a well-developed moderate ground-based temperature inversion, such as commonly occurs at night.” Uncertainty of calculations with this method are +/-1 dB for sources less than 10m in height and within 1000m of the receiver.
8.3.2 Traffic Noise Model
The Federal Highway Administration Traffic Noise Model (TNM), implemented into the SoundPLAN® software, was used for the road traffic sound level modeling in this study. TNM contains the following components:
1. Modeling of five standard vehicle types, including automobiles, medium trucks, heavy trucks, buses, and motorcycles, as well as user-defined vehicles.
2. Modeling both constant- and interrupted-flow traffic using a field-measured data base.
3. Modeling effects of different pavement types, as well as the effects of graded roadways.
4. Sound level computations based on a one-third octave-band data base and algorithms.
5. Graphically-interactive noise barrier design and optimization.
6. Attenuation over/through rows of buildings and dense vegetation.
7. Multiple diffraction analysis.
8. Parallel barrier analysis.
9. Contour analysis, including sound level contours, barrier insertion loss contours, and sound-level difference contours.
These components are supported by a scientifically founded and experimentally calibrated acoustic computation methodology, as well as a flexible data base, made up of over 6000 individual pass-by events measured at forty sites across the country.
City Council Agenda November 7, 2023
1343 Bishop Street, San Luis Obispo, CA 93401
Tel: 805 234 8760 Email: [email protected] October 21, 2022 To: Michael Stoltey – MD3 Investments & Damien Mavis – CoVelop Re: Oak Tree Impact and Protection report for Ardmore Road Project, 2930 Union Rd, Paso Robles, CA 93446
Gentlemen,
In response to your request for an Oak Assessment, Impact and Protection plan for native oaks growing on a lot you intend to purchase and develop at 2930 Union Road, I have produced the following report.
Assignment
• Collect tree data and perform Level 2 inspections on 8 valley oaks (Quercus lobata) to determine condition and suitability for retention.
• Perform advanced Level 3 Assessment with Resistograph for 3 valley oaks. • Provide written summary of condition and suitability for retention for all 8 valley oaks. • Determine Tree Protection Zones (TPZs) for all trees proposed for retention that will potentially have construction impacts occurring in the Critical Root Zone (CRZ) or within 5 feet of the CRZ per City of Paso Robles requirements.
• Produce written oak tree impact and tree protection report based on the International Society of Arboriculture’s (ISA) best management practices for tree protection during construction and City of Paso Robles tree protection requirements.
Report to include:
o Inventory of all trees being impacted
o Critical root zone calculations
o Tree protection zone calculations
o Tree impact assessment
o Tree protection requirements and standards
o Tree protection map with TPZ fencing delineated
o Photographs
Summary
The proposed project is for the construction of a multi-unit, mixed-use industrial site.
In total, I recommended six (6) native oak trees for removal based on structural and health issues.
Proposed tree removals equate to 75% of all oak trees on site.
Tree replacements are required for all native oak trees removed that are six (6) inch diameter and larger. If all proposed oak tree removals are approved, forty-five (45) native oaks at the minimum 1.5- inch caliper or thirty-four (34) native oaks at 2-inch caliper would be required to be planted on the premises or somewhere in the city, upon the Public Works Director’s approval.
City Council Agenda November 7, 2023
2 An International Society of Arboriculture Certified Arborist shall observe and approve all construction activities that occur within or adjacent to the critical root zone (CRZ) of any trees proposed for retention.
A pre-construction meeting shall be held with the project arborist and all parties involved in the project. All tree protection fencing, and tree protection measures shall be in place before any construction activity begins. All necessary pruning shall also be completed before grading and construction.
Introduction
This project is located on an old cattle ranch. Most of the trees had been heavily impacted by cattle and were in severe decline due to root damage and drought or were structurally unstable. On August 2, 2022, I visited the site and performed a basic assessment on all native oaks 6-inch diameter and greater on the property you intend to develop. Initially, I found 4 trees were in such poor condition that I recommended their removal. One (1) tree was in good condition and deemed fit to retain.
As a result of the defects, I found during my basic inspection, 3 of the 8 trees on site required an advanced inspection with a Resistograph, wood density measuring device to determine their structural integrity. I returned to the site on August 5, 2022, and performed the advanced inspections with a Resistograph. On August 12, 2022, I collected additional data for 1 tree via a climbing inspection. I analyzed data collected during the advanced inspections and made recommendations regarding tree condition, tree risk and potential for retention. Ultimately, I determined 1 of the trees included in the advanced inspection could be retained. Combined with the tree deemed retainable during the basic inspection, I recommended 2 native oaks be retained and incorporated within the project.
All tree inspections were based on the potential for a tree to fail within the next 5 years from the date of this report. Any tree retained should be re-inspected on an annual basis to determine health and structural integrity status.
Methodology and Tools
My initial level 2 inspection consisted of a ground based, visual inspection and full walk around of the tree. I used a rubber mallet to sound the trunk to detect decay. I tagged each tree with an aluminum tag and assigned it a number. Based on a previous arborist’s inspection of the trees, I assigned the same number that was listed in their report so we would have consistency when referencing the trees.
Advanced inspections consisted of Resistograph wood density testing, and in one instance, an aerial inspection that consisted of determining the extent of decay with a tape measure.
Tree Diameter Measurements
Diameter at Standard Height (DSH) was measured at 4.5’ above ground. For multi-stem trees that divided below 4.5’, I measured below the division at the narrowest point on the trunk.
If it was not possible to measure below the division, I measured each stem individually, then squared the diameter of each stem. Finally, I summed the squared diameters and took the square root of the sum to get the most accurate diameter of the tree. Diameters were rounded up or down depending on fractions of inches.
City Council Agenda November 7, 2023
3 Tree Numbering
I numbered all trees in the field with a rectangular metal tag and nailed it to the trunk at approximately 5 feet above ground.
Critical Root Zone Measurements
CRZs were determined by giving a radius of 1-foot per every inch of tree diameter. E.g., a 12- inch diameter tree would have a 12-foot CRZ radius measured from the outside of the trunk.
Tree Protection Zone Measurements
Generally, TPZ distances followed the distances listed for CRZs. The exception is if there were proposed tree-root encroachments into the CRZ of less than 25%. In most cases encroachments of less than 25% were allowed unless the structure or health of the tree would be compromised.
TPZ’s were also adjusted if the tree would outgrow the space and cause damage to foundations or cause clearance issues from buildings.
Tree Condition Ratings
All trees in the inventory were given a condition rating. The rating was based on the health, structure and presence of disease and insects. See the following definitions:
• Dead = Severely declining or no foliage, large dead branches, decay cavities, loss of bark, roots decayed or dead.
• Very Poor = Evidence of multiple large past failures, advanced decay, uncontrollable pest infestations or disease infection. Tree in severe decline. • Poor = Tree may be suppressed, drought stressed, or had at least 1 large branch failure.
Disease or pest infestations may be present. Can potentially be retained with attention to mitigation pruning, cultural care changes, pest and disease control. • Fair = May have had minor past failures. Some pests or structural defects may be present, small deadwood. Minor to moderate drought stress present. Defects may be mitigated with pruning and pests can be controlled.
• Good = A relatively healthy tree with minor to no structural defects with minimal to no pest observed. Defects can be mitigated with pruning and pests can be controlled. • Very Good = Trees that have had professional arboricultural care. No structural defects, disease or pests identified.
• Excellent = Specimen tree with superior form, root structure and health. Tree has been regularly cared for by professional arborists over its lifetime, E.g., estate or arboretum tree.
Inspection Levels
Level 1 – Limited Visual Inspection – This is a limited walk-by or drive-by, which does not typically include a complete walk around a tree. The inspection focuses on obvious defects, imminent or probable likelihood of failures. There are generally no tools used at this level. This is the fastest and least thorough assessment.
City Council Agenda November 7, 2023
4 Level 2 – Basic Assessment – Generally includes a complete walk around inspection. Basic tools such as probes, measuring devices, binoculars, mallet or magnifying glass are used. At this level, an aerial inspection is not included. A Level 2 assessment is usually necessary to establish the need for a Level 3 assessment.
Level 3 – Advanced Inspection – Detailed inspection which usually employs the use of special equipment, data collection and analysis. A higher level of training is also required, such as International Society of Arboriculture (ISA) Tree Risk Assessment Qualification. Specialized equipment may include an Air Spade (device that uses compressed air to expose roots or root crown for inspections without causing damage to sensitive plant tissues).
Resistograph (drilling device used to measure and graph wood density) Level 3 inspections may also include sending samples to labs for analysis. A Level 3 inspections will usually take place later because of time needed to perform a Level 2 inspection.
Assessing Tree Structure and Potential to Fail
Estimating the structural integrity of trees is a challenge because, unlike steel I-beams or other construction materials there is no precise engineering standard to help determine the load a tree can withstand. Arborists must use measurement of decay, experience with previous, similar trees as well as factor in the various stressors on the compromised areas within the tree. Trees with thicker outer shells are going to be stronger. Oval internal decay areas and areas of decay that have broken through the outer shell of the trunk or branch will be weaker due to the inconsistency of the cylinder.
Tree Risk
Tree risk is determined by identifying the targets e.g. (people, buildings, cars or property) that could be injured or damaged by a whole or partial tree failure, the occupancy rate, exposure of the target to the tree hazard, the size of part of the tree that may impact the target if it were to fail, the likelihood of impact on the target, and the consequences of failure on the target.
The part of the tree most likely to fail and cause the largest impact is used to determine the highest overall risk for the tree.
When considering likelihood of failure, the definitions are as follows:
• Imminent – Failure has started or most likely to occur in the near future. Even if there is no significant wind or increased load. The imminent category overrides the time frame stated in the scope of work.
• Probable – Failure may be expected under normal weather conditions within the specified time frame.
• Possible – Failure may be expected in extreme weather conditions, but is unlikely during normal weather conditions during a specified time frame. • Improbable – The tree or part is not likely to fail during normal weather conditions and may not fail in extreme weather conditions within the specified time frame.
City Council Agenda November 7, 2023
5 Risk Matrices
I used the International Society of Arboriculture’s Basic Tree Risk Assessment Form to determine risk. Matrix 1 the “Likelihood Matrix” determines the likelihood of failure and impact. The result is entered into Matrix 2, the “Risk Rating Matrix” which factors uses Consequences of Failure to get the overall risk rating. In the example below, Likelihood of failure of a part was Probable. The Likelihood of Impact was High. The result was Likely. In Matrix 2, I entered the result of Likely and entered Severe in the Consequences of Failure which gave me a risk rating of High. See example chart below.
Mitigation
When assessing risk for a tree, it is important to determine if the risk of tree failure can be reduced through mitigation. Mitigation can be made through pruning, installing cabling or bracing support structures. Moving targets out of the strike zone of a tree or restricting access to a tree are also viable mitigation measures. The recommended mitigation should not be so excessive that they compromise the health of the tree.
Tree Risk Assessments
I performed level 2 assessments on trees 1,2,3,4,9,10,11 & 13. See Tree Map Appendix B. From those assessments, I determined that trees 1, 2 and 13 required level 3 advanced inspections. Each assessment below includes a condition rating as well as potential for retention and mitigation recommendations. For level 3 inspections, I included a tree risk assessment matrix.
Tree 1 – A 43” diameter valley oak was in Very Poor condition. See Appendix A - Photographs - Photo 1.
Basic Level 2 Inspection –
This tree had drought stress which was indicated by dead wood in the canopy. It also had decay throughout its scaffold branches which was evident from the presence of decay cavities and woodpecker nests excavated in dead wood. See Appendix A - Photographs - Photos 1 & 4.
City Council Agenda November 7, 2023
6 The trunk had an approximate lean to the east of 10 degrees. It also had a horizontal compression bulge on the east side of its trunk approximately 1’ above ground. Compression bulges or wrinkles, indicate that wood fibers are being crushed by the weight of the canopy and trunk due to lack of supportive structure in the trunk. Further the tree had a large, decayed, anchor root on its southwest side. The root was on the opposing side of the lean of the tree and is likely to fail as decay advances and stress from the weight of the canopy continues to build.
See Appendix A - Photographs - Photos 1-3.
Although this tree had a full canopy it has significant trunk decay. When I sounded the trunk with a rubber mallet, it resounded hollow on all sides. To further confirm the sounding results, I performed an advanced inspection of the decay using a Resistograph.
Advanced Level 3 Inspection -
I took 4 measurements of the wood density of the trunk at 3.5’ above ground. o Sample 1 – west side of tree. Outer shell thickness was 4” o Sample 2 – south side of tree. Outer shell thickness was 6” o Sample 3 – east side of tree. Outer shell thickness was 4” with a small 1.25” pocket of sound wood at 8” laterally, then total decay
o Sample 4 – north side of tree. Outer shell thickness was 5.25” Based on the Resistograph results, it was apparent that the interior wood of the trunk was significantly decayed. The evidence of compression bulges showed that the trunk is losing structural integrity and leaning due to lack of supportive wood fibers.
Armillaria mellea, a.k.a. Oak root fungus is a common disease in valley oaks and is likely the cause of the decay in the roots and the trunk. Christopher J. Luley in his guide Wood Decay Fungi calls this fungus Number one of the “Big Three” of the important decay fungi. Again, according to Mr. Luley, “Armillaria is a root and butt rot fungus that increases the risk of tree failure and is a pathogen capable of killing cambium of roots and lower trunk of stressed trees”.
See Appendix A - Photographs - Photos 29 & 30 for example of failed oak due to root and butt rot.
Parts Assessed – Roots and Trunk
I used the International Society of Arboriculture’s Basic Tree Risk Assessment Form to determine risk for this tree. In Matrix 1 the “Likelihood Matrix” I selected Likelihood of Failure of the roots and trunk as Probable. The Likelihood of impacting a target in a built environment would be High. The resulting Likelihood of Impact was Likely, which I entered into Matrix 2, the “Risk Rating Matrix” in the Likelihood of Failure and Impact section.
For the Consequences of Failure section of Matrix 2, I entered Severe. The Likelihood of Failure and Impact rating combined with the Consequences of Failure resulted in a risk rating of High.
City Council Agenda November 7, 2023
7 Part Assessed – Scaffold Branches
In Matrix 1 the “Likelihood Matrix” I selected Likelihood of Failure of the scaffold branches as Probable. The Likelihood of impacting a target in a built environment would be High. The resulting Likelihood of Impact was Likely, which I entered into Matrix 2, the “Risk Rating Matrix” for the Likelihood of Failure and Impact section. Under Consequences of Failure in Matrix 2, I entered Severe. The Likelihood of Failure and Impact rating combined with the Consequences of Failure resulted in a risk rating of High.
Combined Inspection Results and Risk Assessment
The highest risk rating for this tree was High and was associated with root and trunk failure. I found decay in one anchor root and significant decay was detected in the trunk. Buckling of trunk fibers was evident. Based on shell strength measurements, the likelihood of trunk failure was probable, due to lack of structural integrity. Root failure was Probable due to significant decay in the anchor root on the southwest side of the tree. Scaffold failure was also probable with a high likelihood of failure.
City Council Agenda November 7, 2023
8 Mitigation:
Scaffolds - Reducing the canopy through end weight reduction and removing decayed branches 2” diameter and larger would relieve some stress on remaining scaffold branches and reduce their risk to Moderate.
Roots and Trunk - Reducing the canopy through end weight reduction would relieve some stress on the trunk but not enough to offset the overall stress being exerted on the buckling area on the north side of the tree. No structural support or bracing will help the stability of the tree’s trunk or roots. Significant decay has been detected in the roots as well as the trunk. Based on shell strength measurements, lean of the tree and buckling of wood fibers on the east side of the trunk made failure likely due to lack of structural integrity. I recommend removing the tree before commencement of construction.
Tree 2 – A 47” diameter valley oak was in Poor condition. See Appendix A - Photographs - Photo 5.
Basic Level 2 Inspection –
On the south side of the trunk there was a decay cavity originating at the root-crown and extending approximately 5.5’ upward. When sounded with a rubber mallet on either side of the cavity, it resounded hollow. Moving around the trunk to the east side, I detected another hollow sounding area with my mallet at approximately 3.5’ above ground. See Appendix A - Photographs - Photo 6. Like Tree 1, I suspect Armillaria mellea - Oak root fungus, is the cause of the rot.
At approximately 8 feet above ground, on the southwest side of the trunk there was another decay area that was almost closed over with scar tissue. Although almost closed, I suspected a large area of decay behind the scar. See Appendix A - Photographs – Photo 7. There was a large scaffold branch attached to the trunk above the scar. It had a desiccated fungal fruiting body growing on it and cankers had killed strips of bark near the fungus. See Appendix A - Photographs – Photo 8. I identified the fungi genus to be that of Inonotus. Jessie A. Glaeser and Kevin T. Smith in the winter 2010 issue of Western Arborist, note this fungus to cause a white rot of heartwood in the trunk of living oaks and also decays strips or sections of sapwood, forming elongate cankers and killing the cambium. According to Swiecki, T. J.; Bernhardt, E. A. 2006, A Field Guide to Insects and Diseases of California Oaks, “Inonotus dryophilus is one of the most serious pathogens of living oaks in California associated with decline, failure, and mortality”. In this tree, the weakened trunk area at the scar combined with the heavy, decayed scaffold branch make this section of the tree likely to fail.
In the upper canopy at approximately 14’ above ground there was another decay cavity in the center of the canopy, where a large scaffold branch had failed many years ago. I suspected advanced decay in the trunk at this location. See Appendix A - Photographs - Photo 9.
City Council Agenda November 7, 2023
9 Advanced Level 3 Inspection -
During the aerial inspection, I discovered that the opening of the decayed scaffold in the upper canopy was 13” in diameter. The depth of the cavity was 13’2” deep. When I measured the distance to the ground from the outside of the cavity, it was 14’3”, which illustrated that the entire trunk of the tree was hollow. See Appendix A - Photographs – Photos 9 -14.
From the cavity opening, the decay continued upward into the scaffold branch growing east.
This scaffold is very likely to fail due to weak trunk structure. See Appendix A - Photographs – Photo 12.
Based on the decay detected during mallet sounding, I wanted to investigate the extent of the decay further. I performed an advanced inspection for decay using a Resistograph. I took 6 measurements of the wood density of the trunk at 3.5’ above ground unless otherwise indicated.
o Sample 1 – west side of tree. Outer shell thickness was 8” o Sample 2 – south side of tree, 1’ west of decay cavity, outer shell thickness was 8.5” o Sample 3 – south side of tree at decay cavity seam, outer shell thickness was 3” at 3’ above ground.
o Sample 4 – south side of tree, 1’ east of decay cavity, outer shell thickness was 7.25” o Sample 5 – east side of tree, outer shell thickness was 5.5” o Sample 6 – north side of tree, outer shell thickness was 12” I have highlighted the tables below to show how risk was determined for the part or parts of the tree that was being considered regarding failure potential.
I used the International Society of Arboriculture’s Basic Tree Risk Assessment Form to determine risk for this tree.
Part Assessed - Trunk
In Matrix 1 the “Likelihood Matrix” I selected Likelihood of Failure of the trunk as Probable.
The Likelihood of impacting a target in a built environment would be High. The resulting Likelihood of Impact was Likely, which I entered into Matrix 2, the “Risk Rating Matrix” in the Likelihood of Failure and Impact section. Under Consequences of Failure in Matrix 2, I entered Severe. The Likelihood of the Failure and Impact rating combined with the Consequences of Failure resulted in a risk rating of High.
City Council Agenda November 7, 2023
10 Part Assessed – Scaffold Branches
In Matrix 1 the “Likelihood Matrix” I selected Likelihood of Failure of the scaffold branches as Probable. The Likelihood of impacting a target in a built environment would be High. The resulting Likelihood of Impact was Likely, which I entered into Matrix 2, the “Risk Rating Matrix” for the Likelihood of Failure and Impact section. Under Consequences of Failure in Matrix 2, I entered Severe. The Likelihood of Failure and Impact rating combined with the Consequences of Failure resulted in a risk rating of High.
Combined Inspection Results and Risk AssessmentThe highest risk rating for this tree was High and was associated with trunk and scaffold branch failure. Significant decay was detected in the trunk and eastern scaffold branch.
Based on shell strength measurements, and the void caused by decay on the south side of the tree, the trunk is likely to fail due to lack of structural integrity. In regard to the eastern scaffold branch and other decayed branches, they could be removed, and end-weight could be reduced to relieve some stress on remaining scaffold branches. However, the reduction of the canopy would be close to 50% and would compromise the health of the tree. Further, since the trunk is not structurally sound, this negates the mitigation measure.
Mitigation: Remove tree before commencement of construction. No structural support or bracing will help the stability of the tree’s trunk.
City Council Agenda November 7, 2023
11 Tree 3 – A 47” diameter valley oak was in Very Poor condition. When I sounded the trunk with a rubber mallet, it resounded hollow on the southwest side. A large wound left by a scaffold branch failure in the crown of the tree has since decayed and left a 3’x 4’ hollow at approximately 14’ above ground on the east side of tree. Another decay cavity on the north side of the tree at the same height as the previous, measured approximately 2’ in diameter.
Remaining scaffold was overextended and attached to the decaying trunk. The remaining parts of this tree have a high likelihood of failure. See Appendix A - Photographs – Photos 15 & 16.
Mitigation: Remove tree before commencing project.
Tree 4 – A 52” diameter valley oak was in Very Poor condition. The tree was growing off-site but had critical root zone (CRZ) and crown encroachments into your proposed construction area.
This tree has had several large scaffold branch failures.
At the failure points, significant decay was visible. The remaining scaffolds were overextended and potentially had similar internal decay and had a high likelihood of failure. See Appendix A - Photographs – Photo 17.
Mitigation: I highly recommend removal of this tree due to the advancement of decay in the scaffold branches which is compromising their structural integrity. Crown reduction needed to reduce the risk of scaffold branches failing would take up to 50% of the live canopy and jeopardize the tree’s health. Because this tree is off site, you will need to coordinate with the owner regarding removal.
At minimum this tree should have all overextended branches reduced to help prevent further failures and protect any buildings or other targets you may place on your property within striking distance of the tree. If the owner of the tree chooses to retain it, you will need to design buildings, service and loading zones outside of the CRZ.
Tree 9 – A 51” diameter valley oak was in Very Poor condition. Multiple large scaffold branches had failed. Extensive decay was present at branch failure points. Only 2 overextended scaffold branches remain, and they are connected to a decaying trunk.
When I sounded the trunk with a rubber mallet, it resounded hollow. A 3’ long by 10” wide decay cavity was on the northeast side of trunk. This tree has a high risk of complete failure. See Appendix A - Photographs – Photos 18 & 19.
Mitigation: Remove tree before commencing project.
Tree 10 – A 51” diameter valley oak was in Good condition. The trunk of the tree resounded solid when sounded with a rubber mallet. Tree form was good, but there was some large dead wood and decaying scaffolds. This tree can be retained, but it should have maintenance pruning performed prior to commencement of your project. See Appendix A - Photographs – Photos 20 & 21.
City Council Agenda November 7, 2023
12 Mitigation: Reduce end-weight up to 25% on overextended scaffold branches. Remove dead wood 2” diameter and larger. Remove decayed and structurally unsound scaffold branches.
Supervision of pruning work by the Project Arborist shall be required.
Tree 11 – A 30” diameter valley oak was in Very Poor condition. The tree was in severe decline due to drought stress and root disease. Many of the smaller branches had died. I detected decay at the root crown on the southwest side of the tree. I found an ant nest at the root-crown decay area indicating ants are excavating and nesting in dead roots and root crown.
The dead roots contribute to the decline of the canopy and compromise the stability of the tree.
At least five, 12” average diameter scaffolds had extensive decay on the east side of the tree. To reduce scaffold failure risk, up to 50% of the live canopy would need to be removed, which would compromise the health of and already unhealthy tree. See Appendix A - Photographs – Photos 22-24.
Mitigation: Remove tree prior do commencement of project.
Tree 13 – A 42” diameter valley oak was in Poor condition.
Basic Level 2 Inspection –
The tree had a full canopy with a balanced form. On the south side of the tree at the root crown, there was an area of decay in the underside of one of the anchor roots. Like trees 1 and 2, the decay is likely caused by Armillaria mellea. I also noted the lower trunk was bulging and larger than normal which may indicate butt-rot caused by A. mellea. Further, I observed that the eastern scaffold branch was decayed, and large dead wood was present throughout the canopy.
See Appendix A - Photographs – Photos 25 - 28.
A previous report, by another arborist, expressed concern that a scar at the base of the tree might indicate decay and structural instability. When I sounded the tree’s trunk with a rubber mallet, it resounded solid, except on the north side of the trunk. Due to the difference of opinion regarding the structural integrity of the trunk, I performed an advanced inspection for decay using a Resistograph.
Advanced Level 3 Inspection -
I took 5 measurements of the wood density of the trunk at 3.5’ above ground. o Sample 1 – west side of tree. Outer shell thickness was 7” o Sample 2 – south side of tree. Outer shell thickness was 8.5” o Sample 3 – east side of tree. Outer shell thickness was 8.5” o Sample 4 – east side of tree scarred area on east side of trunk approximately 1’ above ground. Outer shell thickness was 12”.
o Sample 5 – north side of tree. Outer shell thickness was 5” Like Tree 1, the trunk of this tree had advanced internal decay, however when comparing outer shell thickness, this specimen had thicker walls and did not have indications of trunk fibers buckling, therefore its structural integrity is likely stronger.
City Council Agenda November 7, 2023
13 Tree Risk - I used the International Society of Arboriculture’s Basic Tree Risk Assessment Form to determine the risk. I used Matrix 1 the “Likelihood Matrix” on the form and entered the result into Matrix 2, the “Risk Rating Matrix” to get the overall risk rating.
I have highlighted the tables below to show how risk was determined for the part or parts of the tree that was being considered regarding failure potential.
Part Assessed - Root
In Matrix 1 the “Likelihood Matrix” I selected Likelihood of Failure of the roots as Possible.
The Likelihood of impacting a target in a built environment would be High. The resulting Likelihood of Impact was Somewhat Likely, which I entered into Matrix 2, the “Risk Rating Matrix” for the Likelihood of Failure and Impact section. Under Consequences of Failure in Matrix 2, I entered Severe. The Likelihood of Failure and Impact rating combined with the Consequences of Failure resulted in a risk rating of Moderate.
Part Assessed – Trunk
In Matrix 1 the “Likelihood Matrix” I selected Likelihood of Failure of the scaffold branches as Probable. The Likelihood of impacting a target in a built environment would be High. The resulting Likelihood of Impact was Likely, which I entered into Matrix 2, the “Risk Rating Matrix” for the Likelihood of Failure and Impact section. Under Consequences of Failure in Matrix 2, I entered Severe. The Likelihood of Failure and Impact rating combined with the Consequences of Failure resulted in a risk rating of High.
City Council Agenda November 7, 2023
14 Part Assessed – Scaffold Branches
In Matrix 1 the “Likelihood Matrix” I selected Likelihood of Failure of the scaffold branches as Probable. The Likelihood of impacting a target in a built environment would be High. The resulting Likelihood of Impact was Likely, which I entered into Matrix 2, the “Risk Rating Matrix” for the Likelihood of Failure and Impact section. Under Consequences of Failure in Matrix 2, I entered Severe. The Likelihood of Failure and Impact rating combined with the Consequences of Failure resulted in a risk rating of High.
Combined Inspections Results and Risk AssessmentThe highest risk rating for this tree was High and was associated with scaffold and trunk failure. I found decay in one anchor root and significant decay was detected in the trunk, however no bulging of trunk fibers was evident. Based on shell strength measurements, the likelihood of trunk failure is probable due to lack of structural integrity. Scaffold failure was also probable.
Risk of root failure remained moderate.
Mitigation:
Mitigations are meant to reduce risk without compromising the health of the tree. Ultimately, the tree manager, owner or other controlling entity must decide if the residual risk assessed is reasonable.
Scaffold Branches - Reduce end weight on overextended scaffold branches between 25% and 40% to reduce the likelihood of failure. Concentrate reduction more on the northeast and east side of the tree. Remove dead branches 2” diameter and larger. Remove decayed and structurally unsound scaffold branches. Supervision of pruning work by the Project Arborist shall be required. If all pruning recommendations are implemented, the risk of branch failure for the next 12 months will be reduced from High to Moderate.
Roots - Reducing the canopy through end weight reduction will relieve some stress on roots, however due to the overall weight of the canopy and stem, the risk rating for root failure will remain Moderate.
City Council Agenda November 7, 2023
15 Trunk – Scaffold branch reduction will relieve some stress on the trunk of the tree, however it will not likely be enough to lower trunk failure risk to moderate. If this tree is to be retained, and the goal is to reduce the risk rating, the only reasonable way to achieve that goal will be to restrict access by installing a permanent fence around it. The fence shall be a minimum of 4.5’ tall and be built at the limits of the tree protection zone. Once access is restricted, the risk rating will be Moderate. See Trees to be Protected section on page 16 of this report for more detail regarding permanent fencing.
Critical Root Zone Calculations
According to the ISA’s definition, the CRZ is an area of soil around a tree where the minimum number of roots considered critical to the structural stability or health of the tree are located. CRZ determination is sometimes based on the drip line or a multiple of the DSH.
Per City of Paso Robles oak tree ordinance and ISA guidance, the CRZ was determined by assigning a radius of 1-foot per every inch of tree diameter. E.g., a 12-inch diameter tree would have a 12-foot CRZ radius measured from the outside of the trunk. Calculations for all oaks with CRZs potentially being impacted are listed in Appendix E - Tree Inventory and are shown in Appendix D - Tree Protection Map.
Tree Protection Zone Requirements
A tree protection zone or TPZ is similar to a CRZ. Ideally it will be the same size as the CRZ, however it can be smaller. The general rule for CRZ encroachments is that they may be allowed if the impact to critical roots is not more than 25% with no disturbance of Structural Roots (large roots that provide anchorage and stability to the tree).
Once the TPZ limits have been established, tree protection fencing shall be provided for all trees listed for protection. See Table 1 - Tree Protection Zone Measurements on page 17 of this report. Tree protection fencing is required to be in place for the duration of the construction project and shall be installed before starting any ground disturbing activities. • Do not remove any tree protection fencing or enter the TPZ without approval of the project arborist. The fencing shall delineate and protect the tree protection zone.
• The fencing shall at minimum, be 4 feet tall and made of orange, high density, polyethylene with
3.5” x 1.5” openings. It shall be installed on steel posts 8 feet on center and tightly stretched to prevent sagging. I STRONGLY recommend installing 6’ X 8’ temporary, chain-link, fence panels secured to driven steel post. This is a more secure and less moveable option than vinyl fencing that can easily be moved by hand or run over by vehicles. See Appendix C - Tree Protection Diagrams & Photos - Diagram 2 – Temporary Chain-link Fence Panel. • Trunk Protection shall also be provided – Often, the trunk of a tree will be damaged by construction equipment activities. In order to protect as much of the trunk as possible, 2” X 4” wood slats with a minimum height of 8’ shall be placed against the trunk of the tree and secured with wire or zip-ties. DO NOT use anchors such as screws or nails to connect to the trunk. See Appendix C – Tree Protection Diagrams - Diagram 3- Trunk Protection for more detail.
City Council Agenda November 7, 2023
16 • Tree protection signs shall be placed on the TPZ fencing and be spaced 10 feet apart. Signs shall be weatherproof, and state, “Tree Protection Zone – Do Not Enter”. The signs shall also include the project manager’s and project arborist’s phone numbers. Signs shall remain in place until completion of the project. See Appendix C – Tree Protection Diagrams - Diagram 1 – Tree Protection Fencing for further detail.
• No construction or ground disturbance shall be allowed inside the fenced TPZ or CRZ without the project arborist’s permission and/or oversite. If you are unsure whether an activity is allowed, refer to Appendix D - Tree Protection Requirements – Quick Reference List or contact the project arborist Rodney Thurman at 805 234 8760.
Trees To Be Protected
There were 2 native oaks in this project that were selected for retention and will required protection due to proposed construction encroachments inside the CRZ or within 5 feet of tree canopies. All TPZ fencing shall be set as prescribed in Table 1 - Tree Protection Zone Measurements on page 17 and be completed before construction begins. Trunk protection shall also be installed before construction begins. See Appendix C - Tree Protection Diagrams & Photos- Diagrams 1-3.
If construction occurs during the months of June through November, the TPZs shall be irrigated to a depth of 12 inches 1 time before construction begins, which will ensure the trees are properly hydrated.
Additional irrigations during construction may be recommended by the project arborist.
I have recommended retaining and protecting Trees 10 & 13. Refer to Tree Protection Zone map in Appendix B Maps - Map 2.
All work within or adjacent to the CRZs of oak trees will require arborist supervision to ensure that all tree protection measures are implemented. To avoid damage to critical roots, no machine use will be allowed in the TPZ. In order to prevent undue damage to roots when grading, the grading limits along the perimeter of the TPZ shall be DUG BY HAND to the final grading depth. If a root 1” diameter or larger is exposed, it shall not be cut without the project arborist’s permission.
If the project arborist determines that a root over 1-inch diameter needs to be cut, it shall be cut by hand with a pruning saw or reciprocating saw. Once the entire perimeter outside the TPZ has been dug and roots are severed, the project arborist can approve use of machinery to complete excavation and grading if work is outside of the TPZ.
Both trees have gravity walls proposed to be built around them to prevent soil erosion. These walls shall be constructed outside the TPZ fencing area.
Tree 13 requires a permanent fence be built at the limits of the tree protection zone to restrict access. I recommend anchoring it on top of the gravity wall. The fence shall be a minimum of 4.5’ tall and be made of ornamental steel or chain-link mounted on anchored fence posts. The fence openings should not be more than 6” wide. A locked access gate shall be provided to allow maintenance personnel to access the tree. See Appendix C - Tree Protection Diagrams & Photos - Photo A, for permanent fence example.
City Council Agenda November 7, 2023
17 Tree Removals & Tree Pruning
All tree removals and pruning maintenance shall be completed prior to construction activities.
Removals - There were 6 native oak trees that I recommended for removal. They were numbered 1,2,3,4 9 and 11. Reasons for removals are listed in Tree Risk Assessment section of this report. See Appendix A – Photographs for pictures of defects. See Appendix B – Maps - Map 1 for locations.
Tree Pruning - I have recommended that Trees 10 and 13 have mitigation pruning performed. See Appendix B – Maps - Map 1 for locations.
Tree 10 - Reduce end-weight up to 25% on overextended scaffold branches. Remove dead wood 2” diameter and larger. Remove decayed and structurally unsound scaffold branches.
Supervision of pruning work by the Project Arborist shall be required.
Tree 13 - Reduce end weight on overextended scaffold branches between 25% and 40% to relieve stress on and reduce the likelihood of failure. Concentrate reduction more on the northeast and east side of the tree. Remove dead branches 2” diameter and larger. Remove decayed and structurally unsound scaffold branches. Supervision of pruning work by the Project Arborist shall be required.
Oak Tree Replacements
The City of Paso Robles requires replacements for any native oak removed that is 6-inches in diameter or greater. This requirement is at the discretion of the Director of Public Works. The following is excerpted from the city’s Oak Tree Ordinance 835 N.S.:
Replacement oaks being equivalent to twenty-five percent of the diameter of the removed tree(s). (For example, the replacement requirement for removal of two trees of fifteen-inch DBH (thirty total diameter inches), would be seven and one-half inches (thirty inches removed multiplied by twenty-five hundredths replacement factor).
Table 1 - Tree Protection Zone Measurements
Tree # DSH CRZ TPZ Fence Distance
from tree trunk
% CRZ
Impact Specific Protection Requirements
10 51” 51’
51’ North, 48’
South.
53’ East & West
< 5
Set TPZ fencing according to measurements
provided. Refer to Tree Protection Zone map in
Appendix B Maps - Map 2
13 42” 42’ 42’ all directions 0
Set TPZ fencing according to measurements
provided. Refer to Tree Protection Zone map in
Appendix B Maps - Map 2
City Council Agenda November 7, 2023
18 This requirement could be satisfied by planting five, one and one-half inch caliper trees, or three, two-and one-half-inch caliper trees or any other combination totaling seven and one-half inches).
A minimum of two, twenty-four-inch box, one and one-half inch minimum trunk caliper measurement trees shall be required for each oak tree removed.
Replacement trees shall be located on the same property as where the tree is approved for removal or, subject to approval of the director, arrangements can be made to locate the replacement trees on public property. Planting standards for replacement trees shall he consistent with City Standard Details and Specification L-4 except that deep root barriers shall not be required if the trees are not adjacent to sidewalk areas. Oak tree preservation and maintenance measures shall be consistent with the provisions of this chapter.
The combined diameter of the oak trees proposed for removal within your project is 270 inches.
Twenty-five percent of 270 inches is 67.5 inches. Therefore, forty-five (45) native oaks at the minimum
1.5-inch caliper or thirty-four (34) native oaks at 2-inch caliper would be required to be planted on the premises or somewhere in the city, upon the Public Works Director’s approval.
When incorporating new oak trees into your landscape, you will need to allow for at least an 8’ x 8’ planting area. Curbing for the planting area shall not count as part of the planting area dimensions.
Planting areas smaller than 8’x 8’ will result in sidewalk and curb buckling when tree roots mature.
Distances between oak trees should be no less than 25 feet. If oak trees can be incorporated into open, non-hardscape areas, they will have a higher success rate. Planting trees in groups of 3, in larger landscape planting islands is also a great way to ensure better root health and tree survival rates while maximizing parking lot shade benefits.
Landscaping – Irrigation - Amenities
Tree 10 –
• Do not till or trench within the TPZ to install landscaping or irrigation. • Install only drought tolerant and preferably California native plants beneath the tree canopy. • Irrigation shall be drip-type and all supply hoses shall be routed above ground. • Do not install overhead sprinkler irrigation because it will introduce too much moisture and potentially rot the tree’s roots.
• Do not install weed block cloth beneath the canopy of the tree. It restricts rainwater from percolating into the soil.
• Provide decorative bark as a top dressing to help retain moisture in the root zone. • Do not construct permanent concrete or brick patios beneath the canopy of the tree. • Install Raised deck patios. They are the preferred treatment for seating areas within the critical root zones of trees.
Tree 13 –
• DO NOT provide any permanent or temporary amenities such as patios or seating beneath the canopy of this tree.
• Do not till or trench within the TPZ to install landscaping or irrigation. • Install only drought tolerant and preferably California native plants beneath the tree canopy. • Irrigation shall be drip-type and all supply hoses shall be routed above ground.
City Council Agenda November 7, 2023
19 • Do not install overhead sprinkler irrigation because it will introduce too much moisture and potential rot the tree’s roots.
• Do not install weed block cloth beneath the canopy of the tree. It restricts rainwater from percolating into the soil.
• Provide decorative bark as a top dressing to help retain moisture in the root zone.
Pre-Construction Meeting
Prior to any construction or ground disturbing activities, the project arborist shall meet with all contractors involved with the development of this project to review tree protection measures. Any new contractors brought on site shall also meet or communicate with the project arborist by phone or video conference to ensure they are aware of all tree protection measures.
Conclusion
Although many of the mature trees on site were not safe to retain, two trees were viable and had good potential to be retained as an asset to your project if all site design recommendations and tree protection measures are implemented. With required native oak replacements, you will have the opportunity to build your project while also restoring a native oak forest on site.
Respectfully Submitted,
Rodney D. Thurman
ISA Board Certified Master Arborist PN-2684BUM
ISA Municipal Specialist
ISA Utility Arborist
ISA Tree Risk Assessor Qualification
Appendices: photographs, maps, tree protection diagrams & photos, tree protection quick reference list
City Council Agenda November 7, 2023
20 Appendix A - Photographs
Photo 1 - View of Tree 1 to south. Note
lean to east.
City Council Agenda November 7, 2023
21 Photo 2 - Tree 1 with decayed anchor root on southwest side, indicated by arrow. Ink pen provided for scale
City Council Agenda November 7, 2023
22 Photo 3 - Tree 1 with compression bulge east side of trunk indicated by arrow shows lack of structural support.
City Council Agenda November 7, 2023
23 Photo 4 - Tree 1 with decay in scaffold branches. indicated by arrows.
City Council Agenda November 7, 2023
24 Photo 5 - View of Tree 2 to north
City Council Agenda November 7, 2023
25 Photo 6 - Tree 2 with decay cavity south side of trunk. Length is approximately 5.5’.
City Council Agenda November 7, 2023
26 Photo 7 - Tree 2 with decay cavity at scaffold union approx. 8’ above ground on southwest side of tree.
City Council Agenda November 7, 2023
27 Photo 8 - Tree 2 with fungal fruiting body circled and decay in south scaffold branch indicated by arrow.
City Council Agenda November 7, 2023
28 Photo 9 - Tree 2 with decay cavity formed by failed scaffold circled at center of tree, approximately 14 feet above ground.
City Council Agenda November 7, 2023
29 Photo 10 - Tree 2 perspective view of decay cavity formed by failed scaffold circled at center of tree. Cavity is circled. Other decay points below the open cavity are indicated by arrows.
City Council Agenda November 7, 2023
30 Photo 11 - Tree 2 view of decay cavity formed by failed scaffold.
Opening measures 13”
City Council Agenda November 7, 2023
31 Photo 12 - Tree 2 view of interior decay cavity formed by failed scaffold. Arrow 1 shows depth of cavity down to roots of tree.
Arrow 2 shows decay that has advanced into eastern scaffold branch.
#2
#1
City Council Agenda November 7, 2023
32 Photo 13 - Tree 2 measurement of
interior depth of decay cavity formed by
failed scaffold. 13’ 2”
Photo 14 - Tree 2 measurement of
exterior depth of decay cavity formed by
failed scaffold. 14’ 3”
City Council Agenda November 7, 2023
33 Photo 15 - View of Tree 3 to north. Overextended scaffold to west. Large decay cavity at connection to trunk.
City Council Agenda November 7, 2023
34 Photo 16 - Tree 3 with large decay cavity at scaffold connection to trunk.
City Council Agenda November 7, 2023
35 Photo 17 - View of Tree 4 with to northwest. Numerous failed scaffold branches due to overextension and internal decay.
City Council Agenda November 7, 2023
36 Photo 18 - View of Tree 9 to north. Numerous failed scaffold branches due to overextension and internal decay.
City Council Agenda November 7, 2023
37 Photo 19 - Tree 9 close-up of failed scaffold branch with internal decay.
City Council Agenda November 7, 2023
38 Photo 20 - View of Tree 10 to south.
City Council Agenda November 7, 2023
39 Photo 21 - Tree 10 with decayed scaffold branch indicated by yellow arrows.
City Council Agenda November 7, 2023
40 Photo 22 - View of Tree 11 to north. At least 5 decayed scaffold branches would be removed which would reduce the tree at least 50%. Arrows indicate branch removal points.
City Council Agenda November 7, 2023
41 Photo 23 - Tree 11 close up of declining canopy, decayed branches, and dead wood indicated by arrows.
City Council Agenda November 7, 2023
42 Photo 24 - Tree 11 close up of root crown decay at southwest side of tree indicated by yellow arrow. Ant nest discovered here which indicates dead and rotting wood.
City Council Agenda November 7, 2023
43 Photo 25 - View of Tree 13 to north. Note overextended scaffold branches indicated by arrows.
City Council Agenda November 7, 2023
44 Photo 26 - Tree 13 with root decay cavity on south side of tree indicated by arrow.
City Council Agenda November 7, 2023
45 Photo 27 - Tree 13 with bulging root-crown indicating possible butt-rot.
City Council Agenda November 7, 2023
46 Photo 28- Tree 13 with decaying scaffold branch east side of canopy indicated by arrow. Line indicates locations for removal
City Council Agenda November 7, 2023
47 Photos 29 & 30 - Example of oak tree that failed due to root and butt-rot. Photo 29 shows failed roots. Photo 30 shows internal decay of trunk.
City Council Agenda November 7, 2023
48 Appendix B – Maps
Map 1 - Tree Locations
Legend – Red = removals, Green = retain and protect, Dashed line delineates property boundaries.
2 1 9
10 13
3 11
4 Home
City Council Agenda November 7, 2023
49 Map 2 - Tree Protection Zones
Red dashed line = TPZ fence location. Set fence according to distances provided. See Table 1 - Tree Protection Zone Measurements in this report as well as full sized Tree Protection Zone Map in plan set for more detail. This map has been cropped from the original provided by Wallace Group.
42’
51’
47’
42’ 42’
42’
53’
53’
48’
TPZ Fencing
TPZ Fencing
BLDG. 2
BLDG.
BLDG.
5 Tree
10 Tree
13
City Council Agenda November 7, 2023
50 Appendix C – Tree Protection Diagrams & Photos
TREE PROTECTION
Crown drip line or other limit of Tree Protection area. See tree preservation plan for fence alignment.
4'-0"
Maintain existing
grade with the tree
protection fence
unless otherwise
indicated on the
plans.
2" x 6' steel posts
or approved equal.
Tree Protection
fence: High density
polyethylene fencing
with 3.5" x 1.5"
openings; Colororange. Steel posts
installed at 8' o.c.
5" thick
layer of mulch.
Notes:
1- See specifications for additional tree
protection requirements.
2- If there is no existing irrigation, see
specifications for watering requirements.
3- No pruning shall be performed except
by approved arborist.
4- No equipment shall operate inside the
protective fencing including during fence
installation and removal.
5- See site preparation plan for any
modifications with the Tree Protection
area.
SECTION VIEW
KEEP OUT
TREE
PROTECTION
AREA
8.5" x 11"
sign
laminated in
plastic spaced
every 10'
along the
fence.
URBAN TREE FOUNDATION © 2014
OPEN SOURCE FREE TO USE
Diagram 1 –Vinyl Tree Protection Fencing
City Council Agenda November 7, 2023
51 Diagram 2 – Temporary chain-link fence panel
City Council Agenda November 7, 2023
52 Diagram 3 – Trunk Protection
City Council Agenda November 7, 2023
53 Photo A – Example of permanent fencing to exclude human activity beneath tree.
City Council Agenda November 7, 2023
54 Appendix D - Tree Protection Requirements - Quick Reference List Tree Protection During Construction - Tree protection shall be provided during the entire time construction activities occur. A Tree Protection Zone (TPZ) shall be established and maintained to ensure protected roots remain undisturbed.
Tree Protection Fencing - Tree protection fencing is required to be in place for the duration of the construction project and shall be installed before starting any ground disturbing activities. Do not remove any tree protection fencing or enter the TPZ without approval of the project arborist. The fencing shall delineate and protect the tree protection zone. The fencing shall be at minimum, 4 feet tall and made of orange, high density, polyethylene with 3.5” x 1.5” openings. It shall be installed on steel posts 8 feet on center and tightly stretched to prevent sagging. I STRONGLY recommend installing 6’ X 8’ temporary, chain-link, fence panels secured to driven steel post. This is a more secure and less moveable option than vinyl fencing that can easily be moved by hand or run over by vehicles. See Appendix C - Tree Protection Diagrams & Photos- Diagrams 1 & 2 – Tree Protection Fencing.
Trunk Protection - Trunk protection is required. The trunk shall also be protected by installing 2x4’s against the trunk and securing them with zip-ties or wire. Do not anchor wood or wire directly to trunk. See Appendix C - Tree Protection Diagrams & Photos- Diagram 3 – Trunk Protection.
Tree Protection Signage - Weatherproof, tree protection signs stating, “Tree Protection Zone – Do Not Enter” shall be placed on the fencing & be spaced 10 feet apart. The Project Arborist’s and General Foreman’s contact numbers shall also be included on the sign. Signs shall remain in place until completion of the project. See Appendix C - Tree Protection Diagrams & PhotosDiagram 1 – Tree Protection Fencing.
Pre-Construction Meeting - A meeting with all contractors involved in the project shall occur with the project arborist before beginning construction activities. Any new contractors brought on site shall also meet or communicate with the project arborist to ensure they are aware of tree protection measures.
Preparing Tree Protection Zone - If construction occurs during the months of June through November, the TPZ’s shall be irrigated to a depth of 12 inches before construction begins. This will ensure the trees are properly hydrated. Additional irrigations during “heat-waves” may be recommended by the project arborist.
Root Protection - No grading, trenching, paving or any other soil disturbance shall occur within or adjacent to the TPZ of the tree without permission and supervision by the project arborist. No trenching or excavation for footings, foundations, utilities or roadways shall occur within or adjacent to the TPZ without first, hand trenching the location and exposing roots.
If possible, conduit or other utilities shall be “fished” below roots larger than 1-inch diameter. Any roots 1-inch diameter or larger that are approved for pruning shall be hand cut with a clean pruning saw or Sawzall. Once roots are hand cut, machinery can remove the severed roots. Cutting any roots 1-inch diameter or larger requires supervision by the project arborist.
Root Pruning - If the project arborist determines that a root over 1-inch diameter needs to be cut, it shall be cut by hand with a pruning saw or reciprocating saw “Sawzall”. After cutting a root, the area shall be backfilled as soon as possible with moist soil or covered with wet burlap until backfill can be completed. Burlap shall be kept wet the entire time it is in use for cut-root protection.
Dumping, Cleanout or Storage of Materials - No construction materials, soils, or debris shall be stored in the TPZ. No concrete, plaster, paint or chemical washout shall be allowed within the Tree Protection Zone (TPZ) or Critical Root Zone (CRZ).
Monitoring - An initial inspection shall be completed by the project arborist prior to commencement of construction activities to ensure that all tree protection measures have been put in place. Weekly inspections of the TPZ and associated fencing shall also be completed by the project arborist until construction is complete. Any root pruning, excavation, grading or filling within 5 feet of the TPZ shall a be monitored by the project arborist.
Project Arborist Contact Information - Rodney Thurman – Heritage Tree Arboricultural Consulting – Cell: 805 234 8760 – Email:
[email protected]
City Council Agenda November 7, 2023
3/14/2023
LAND USE TYPE QUANTITY UNIT
TOTAL DEMAND
(acre-ft/yr.) NOTES
Large Warehouse 116,812 SF 1.6
144 employees (assumed based on number of parking spaces) @ 10 gpd1
Office 9,000 SF 0.8 125 sf/employee, 10 gpd1
/employee (Metcalf & Eddy)
Commercial 7,392 SF 0.3 Assume 250 sf/employee, 10 gpd1 /employee
Storage 40,271 SF 0.0
Manufacturing 25,836 SF 6.7 6,000 gpd 2
- Assume Food Processing/Winery as worst case
Wine Making 41,016 SF 7.7 6,900 gpd 2
Landscape 2.63 AC 3.7 Based upon EAWU
TOTAL ESTIMATED WATER USE 21 acre-ft/year
Ardmore Industrial
PRELIMINARY ESTIMATE OF WATER USE
Building 1
Building 2-6
2. Estimate based upon historical Wallace Group knowledge
1. Taken from Wastewater Engineering, Treatment and Reuse , 4th Edition, Metcalf and Eddy.
City Council Agenda November 7, 2023
3/9/2023
LAND USE TYPE QUANTITY UNIT
TOTAL DEMAND
(gal/day) NOTES
Large Warehouse 116,812 SF 1,440
144 employees (assumed based on number of parking spaces) @ 10 gpd1
Office 9,000 SF 720 125 sf/employee 10gpd1
/employee
Buildings 2-6 (Industrial Flex)
Commercial 7,392 SF 296 Assume 250 sf/employee, 10gpd1
/employee
Storage 40,271 SF 0
Manufacturing 25,836 SF 6,000 6,000 gpd 2
- Assume Food Processing/Winery as worst case
Wine Making 41,016 SF 6,900 6,900 gpd 2
TOTAL ESTIMATED SEWAGE USE (PRE-TREATMENT REQUIRED) 15,356 gpd 11 gpm
Design Flow 21 gpm - 2.0 Peaking Factor
2. Estimate based upon historical Wallace Group knowledge Ardmore Industrial
PRELIMINARY ESTIMATE OF WASTEWATER DEMAND
Building 1
1. Taken from Wastewater Engineering, Treatment and Reuse , 4th Edition, Metcalf and Eddy.
City Council Agenda November 7, 2023
Mitigation Monitoring and Reporting Plan
Project File No./Name: Covelop Project – Ardmore Road
Approving Resolution No.: by: Planning Commission City Council Date: September 26, 2023 The following environmental mitigation measures were either incorporated into the approved plans or were incorporated into the conditions of approval. Each and every mitigation measure listed below has been found by the approving body indicated above to lessen the level of environmental impact of the project to a level of non-significance. A completed and signed checklist for each mitigation measure indicates that it has been completed.
Explanation of Headings:
Type: ............................................................ Project, ongoing, cumulative Monitoring Department or Agency: ........ Department or Agency responsible for monitoring a particular mitigation measure Shown on Plans: .........................................When a mitigation measure is shown on the plans, this column will be initialed and dated.
Verified Implementation: ..........................When a mitigation measure has been implemented, this column will be initialed and dated.
Remarks: ...................................................... Area for describing status of ongoing mitigation measure, or for other information.
Mitigation Measure
PD 22-20, CUP 22-20, VTPM 22-0054, OTR
(Covelop)
Type
Monitoring
Department
or Agency
Shown on Plans Verified
Implementation Timing/Remarks
To reduce any potentially significant impact on nesting birds from vegetation removal to a less than significant level, the following mitigation measures are
recommended.
MM BIO-1: Vegetation removal and initial site disturbance shall be conducted between
September 1 and January 31 outside of the nesting season for birds. If vegetation and/or tree removal is planned for the bird nesting season (February 1 to August 31), then preconstruction nesting bird surveys shall be conducted by a qualified biologist to determine if any active nests would be impacted by project construction. If no active nests are found, then no further mitigation shall be required.
OngoingCDD Prior to issuance of
grading permit
Exhibit C
City Council Agenda November 7, 2023
Mitigation Measure
PD 22-20, CUP 22-20, VTPM 22-0054, OTR
(Covelop)
Type
Monitoring
Department
or Agency
Shown on Plans Verified
Implementation Timing/Remarks
If any active nests are found that would be impacted by construction, then the nest sites shall be avoided with the establishment of a non-disturbance buffer zone around
active nests as determined by a qualified biologist. Nest sites shall be avoided and protected with the nondisturbance buffer zone until the adults and young of the year are no longer reliant on the nest site for survival as determined by a qualified biologist. As such, avoiding
disturbance or take of an active nest would reduce
potential impacts on nesting birds to a less-than-significant level.
MM BIO-2: To avoid direct take of SJKF during construction in accordance with theSFWS and San Luis Obispo County
Guide to SJKF Mitigation Procedures Under CEQA, the
project owner shall adopt the Standard Kit Fox CEQA
Mitigation Measures and shall be included on
development plans. The following measures shall be
implemented:
• A maximum 25 mph speed limit shall be required at
the project site during construction activities.
• All construction activities shall cease at dusk and not start before dawn.
• A qualified biologist shall be on-site immediately prior to initiation of project activities to inspect for any large burrows (e.g., known and potential dens) and to
ensure no wildlife are injured during project activities. If dens are encountered, they should be avoided as
discussed below.
• Exclusion zone boundaries shall be established around all known and potential SJKF dens.
Project CDD Notes shown on
construction
documents.
Prior to issuing Building
Permit.
Exhibit C
City Council Agenda November 7, 2023
Mitigation Measure
PD 22-20, CUP 22-20, VTPM 22-0054, OTR
(Covelop)
Type
Monitoring
Department
or Agency
Shown on Plans Verified
Implementation Timing/Remarks
• All excavations deeper than 2 feet shall be completely covered at the end of each working day, or fitted with
wildlife escape ramps.
• All pipes, culverts, or similar structures shall be
inspected for SJKF and other wildlife before burying,
capping, or moving.
• All exposed openings of pipes, culverts, or similar
structures shall be capped or temporarily sealed prior
to the end of each working day.
• All food-related trash shall be removed from the site at the end of each workday.
• Project-related equipment shall be prohibited outside of designated work areas and access routes.
• No firearms shall be allowed in the project area.
• Disturbance to burrows shall be avoided to the
greatest extent feasible.
• No rodenticides or herbicides should be applied in the project area.
• Permanent fences between any remaining habitat
areas shall allow for SJKF passage through or
underneath (i.e., an approximate 4-inch passage gap
shall remain at ground level).
• To avoid take of any SJKF and/or active SJKF dens,
within 30 days prior to the initiation of site disturbance, implement the SJKF den survey and den closure
protocol for unoccupied dens. Any SJKF occupied
dens shall be avoided until the SJKF leave the den/site. • Prior to issuance of grading and/or construction permit and within 30 days prior to initiation of site disturbance and/or construction, all personnel associated with the
project shall attend a worker education training
program, conducted by a qualified biologist, to avoid
or reduce impacts on sensitive biological resources
(i.e. San Joaquin kit fox). At a minimum, as the
Exhibit C
City Council Agenda November 7, 2023
Mitigation Measure
PD 22-20, CUP 22-20, VTPM 22-0054, OTR
(Covelop)
Type
Monitoring
Department
or Agency
Shown on Plans Verified
Implementation Timing/Remarks
program relates to the kit fox, the training shall include the kit fox’s life history, all mitigation measures
specified by the City, as well as any related biological report(s) prepared for the project. The applicant shall notify the City shortly prior to this meeting. A kit fox fact sheet shall also be developed prior to the training
program, and distributed at the training program to all contractors, employers and other personnel involved
with the construction of the project.
• During the site-disturbance and/or construction phase, any contractor or employee that inadvertently kills or
injures a San Joaquin kit fox or who finds any such
animal either dead, injured, or entrapped shall be
required to report the incident immediately to the
applicant and City. In the event that any observations
are made of injured or dead kit fox, the applicant shall immediately notify the USFWS and CDFW by
telephone. In addition, formal notification shall be
provided in writing within three working days of the
finding of any such animal(s). Notification shall include the date, time, location and circumstances of the
incident. Any threatened or endangered species
found dead or injured shall be turned over
immediately to CDFW for care, analysis, or disposition.
MM CUL-1 In the event that cultural resources including human remains are encountered during ground
disturbance activity, the project shall stop all activity within a 100-foot radius of the find and the project archaeologist shall access the situation with the County Coroner to verify the next steps and determine when construction may
resume.
Project CDD Prior to site
disturbance, grading
permit issued
(add additional measures as necessary)
Exhibit C
City Council Agenda November 7, 2023
Explanation of Headings:
Type: ............................................................ Project, ongoing, cumulative Monitoring Department or Agency: ........ Department or Agency responsible for monitoring a particular mitigation measure Shown on Plans: .........................................When a mitigation measure is shown on the plans, this column will be initialed and dated.
Verified Implementation: ..........................When a mitigation measure has been implemented, this column will be initialed and dated.
Remarks: ...................................................... Area for describing status of ongoing mitigation measure, or for other information.
Exhibit C
City Council Agenda November 7, 2023
Attachment 8
RESOLUTION 23-XXX (B)
A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF EL PASO DE ROBLES APPROVING PLANNED DEVELOPMENT 22-20, CONDITIONAL USE PERMIT 23-14, AND OAK TREE REMOVAL PERMIT 23-11
2930 UNION ROAD, APN: 025-362-043
APPLICANT – COVELOP/MD3
WHEREAS, the City of Paso Robles has received applications from Kirk Consulting on behalf of Covelop/MD3, requesting a commercial subdivision, development plan, conditional use permit, and oak tree removal permit, to develop an approximate 14-acre site with six (6) commercial/light industrial buildings totaling 240,327± square feet; and
WHEREAS, the Project will require the following entitlements: Planned Development PD 22-20, Oak Tree Removal 23-11 for six (6) native oak trees, Vesting Tentative Parcel Map PR 22-0054, and Conditional Use Permit 23-14; and
WHEREAS, the site has a General Plan land use designation of Commercial Service (CS) and is in the Commercial Light-Industrial zoning district, Planned Development zoning overlay (C3-PD); and WHEREAS, Vesting Tentative Parcel Map PR 22-0054 would subdivide Parcel 6, which is currently 6.76 (net) acres, into two parcels where Parcel A would be 4.03 acres and Parcel B would be 2.73 acres. Existing Lot 13 is approximately 7 acres and while included as part of the development plan, is not included in the subdivision; and
WHEREAS, commercial and light-industrial uses, included warehousing, are allowed uses in the C3-PD zoning district, and are not considered detrimental to the City’s efforts to revitalize the downtown; and WHEREAS, this project is located in the geographic area east of Golden Hill Road, south of Union Road and Highway 46 East, and is subject to Zoning Code Section 21.13.030F, to ensure the project is designed in a manner that is compatible with the neighboring land uses, including the residentially zoned property to the south of Lot 13; and
WHEREAS, the purpose and intent of the planned development (PD) district zoning overlay is to provide for innovation and flexibility in the design of residential, commercial, and industrial developments. Approval of a development plan is required for all development in the planned development (overlay) district; and WHEREAS, pursuant to the Statutes and Guidelines of the California Environmental Quality Act (CEQA), Public Resources Code, Section 21000, et seq., and the City’s Procedures for Implementing CEQA, an Initial Study and a Draft Mitigated Negative Declaration (MND) SCH 2023090132 were prepared and circulated for a 30-day public review period beginning on September 11, 2023 and October 10, 2023, and notice thereof was provided by: (1) filing a Notice of Intent to Adopt a Mitigated Negative Declaration (NOI) with the State Clearinghouse; (2) filing an NOI with the San Luis Obispo County Clerk; (3) placing an NOI in the Tribune Newspaper, a newspaper of general circulation; (4) mailing the NOI to various interested persons, agencies, and tribes; and (5) posting the NOI on the City website; and
City Council Agenda November 7, 2023
Attachment 8
WHEREAS, the Development Review Committee (DRC) reviewed the design of the project at their meeting on July 31, 2023, where they were in favor of the project and recommended that the project be scheduled before the Planning Commission for review. The DRC requested more detailed information related to internal pedestrian connectivity, truck turning movements, and additional perspective views of buildings would be helpful for the Planning Commission to review; and
WHEREAS, a public hearing was conducted by the Planning Commission on October 10, 2023 to consider the Final MND prepared for the proposed project, and to accept public testimony and written comments on the Development Plan, Oak Tree Removal Permit, Vesting Tentative Parcel Map, Conditional Use Permit, and environmental determination. At the close of this public hearing, the Planning Commission recommended, on a 5-0 vote (two Commissioners were absent), that the City Council adopt the MND and the proposed Project with the addition of conditions of approval to address the APCD letter; and WHEREAS, a public hearing was conducted by the City Council on November 7, 2023 to consider the Final MND prepared for the proposed project, and to accept public testimony on the Development Plan, Oak Tree Removal Permit, Vesting Tentative Parcel Map, Conditional Use Permit, and environmental determination.
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF EL PASO DE ROBLES DOES HEREBY RESOLVE AS FOLLOWS:
Section 1: Recitals. All of the above recitals are true and correct and incorporated herein by reference.
Section 2: Findings. Based upon the facts and analysis presented in the staff report, public testimony received, and subject to the conditions listed below, the City Council makes the following findings:
Development Plan Findings
1. The design and intensity of the proposed development plan is consistent with the goals and policies established by the general plan and the zoning code, particularly the purpose and intent of the zoning district in which a development project is located, because the project would provide for additional commercial light-industrial, and warehouse uses consistent with the Commercial Service land use and Commercial Light-Industrial zoning designations.
2. The proposed development plan will not be detrimental to the health, safety, morals, comfort, convenience and general welfare of the residents or businesses in the surrounding area, or be injurious or detrimental to property and improvements in the neighborhood or to the general welfare of the City, as a result of the site planning demonstrating required setbacks and adequate landscaping; and
3. The proposed development plan accommodates the aesthetic quality of the City as a whole, especially where development will be visible from the gateways to the City, scenic corridors; and the public right-of-way, based on the mixture of quality materials and landscaping.
4. The proposed development plan is compatible with, and is not detrimental to, surrounding land uses and improvements, provides appropriate visual appearance, and contributes to the mitigation of any environmental and social impacts as outlined in the MND prepared for this project.
City Council Agenda November 7, 2023
Attachment 8
5. The proposed development plan is compatible with existing scenic and environmental resources such as hillsides, stream courses, oak trees, vistas, and historic buildings and structures; because although six oak trees will be removed, additional mitigation oak trees will be planted onsite.
6. The proposed development plan contributes to the orderly development of the city as a whole by providing a well-designed project that is suitable for the location where it is proposed and surrounding land uses including commercial and light industrial uses, and the existing and future Chandler Ranch residential area to the south of Lot 13.
Planned Development Overlay District Findings
1. The granting of this permit will not adversely affect the policies, spirit and intent of the general plan, applicable specific plans, the zoning code and all other adopted codes, policies, and plans of the city because commercial, light-industrial, and warehousing uses are consistent with the intent of the Commercial Service General Plan land use designation.
2. The proposed project maintains and enhances significant natural resources on the site because it will retain two of eight oak trees and will incorporate additional replacement oak trees into the site’s landscape plan for the six oak trees to be removed.
3. The proposed project is designed to be sensitive to, and blend in with, the character of the site and surround area, and would not have an adverse effect on the public views from nearby roads and other public vantage points, because it will provide commercial, light-industrial, and warehouse buildings of similar scale and architectural quality as other businesses in the vicinity.
4. The proposed project's design and density of the developed portion of the site is compatible with the established character and scale of surrounding development and would not be a disharmonious or disruptive element to the neighborhood because it similar scale and architectural quality as other businesses in the vicinity.
5. The development would be consistent with the purpose and intent of this Planned Development District chapter of the Zoning Ordinance and would not be contrary to the public health, safety, and welfare because it does not include significant modification from code requirements as can be permitted in the PD Overlay district.
6. Modification of the standards as set forth in this chapter or elsewhere in the zoning ordinance shall only be approved upon a finding that greater public benefit would be achieved through such modifications. Additionally, for planned development projects that are seeking an increase in allowable building heights, modification of the height limitations shall only be approved upon a finding that the proportion, scale, and nature of the project is such that the modifications would not create an adverse visual impact nor compromise the safety of occupants. The project does not include a modification of the height limit.
Conditional Use Permit Findings:
City Council Agenda November 7, 2023
Attachment 8
1. The project has been designed in a manner that provides a 6-foot decorative masonry wall and a 10-foot-wide landscape planter which will provide visual screen from the residentially zoned land (North Chandler Ranch) to the south as required by Section 21.13.030.F.1a & b., as a result of the wall and the planter area, and since this project is not proposing any outdoor storage of equipment or materials, the project has been designed to adequately screen the site from the residential land to the south.
2. The project has been designed with commercial and light-industrial uses that do not create noise, visual and/or land use impacts to neighboring land uses, because of the design of the project providing perimeter setbacks, walls, fencings, landscape planters to help separate the project from neighboring land uses.
3. The Covelop/MD3 project includes commercial light-industrial uses along with warehousing, which are uses that will not have a detrimental effect on the city’s goal to revitalizing the downtown.
Oak Tree Removal Permit Finding
1. For the six (6) valley oak trees (Tree Nos. 1, 2, 3, 4, 9 and 11), although rated very poor condition, the necessity of the requested action is to allow reasonable use of the property for which it has been zoned by allowing construction of the project. Because the building has been considered for alternative designs and the site plan has undergone changes to retain the two healthiest oak trees on the property (Tree Nos. 10 and 13), every reasonable effort has been made to avoid impacting oak trees, consistent with Paso Robles Municipal Code Section 10.01.050.D. Additionally, mitigation trees (totaling 67.7- inches in diameter) are being provided with the new landscape plan for the project to mitigate for the loss of Trees. 1, 2, 3, 4, 9 and 11.
Section 3: Environmental Determination. In accordance with the California Environmental Quality Act (Public Resources Code §§ 21000 et seq., “CEQA”), and the regulations promulgated thereunder (14 Cal.
Code of Regulations §§ 15000 et seq., the “CEQA Guidelines), the City prepared an Initial Study/Mitigated Negative Declaration (SCH #2023090132) (“MND”) that analyzed the proposed Project’s environmental impacts. The MND was made available to the public for review from September 11, 2023 through October 10, 2023. On November 7, 2023, the City Council conducted a duly noticed public hearing and considered the entire administrative record (as of that date), including staff reports, the MND, MMRP, and oral and written testimony from interested persons, all of whom were given an opportunity to be heard.
Resolution No. 2023-__ recommends adoption of the MND and MMRP, and, among other things, properly assesses the environmental impact of the Project in accordance with CEQA. This Resolution incorporates by reference the environmental findings and analysis set forth in Resolution No. 2023-__, including the MND, as if fully set forth herein.
Section 4: Approval. The City Council approves Planned Development 22-20, Conditional Use Permit 223- 14, and Oak Tree Removal Permit 23-11, subject to the following:
City Council Agenda November 7, 2023
Attachment 8
EXHIBIT DESCRIPTION
A Site-Specific Conditions of Approval
B Standard Conditions of Approval
C Revised Plan Set
D Oak Assessment Report
APPROVED this 7th day of November 2023, by the following vote:
AYES:
NOES:
ABSENT:
ABSTAIN:
JohnR. Hamon, Jr., Mayor
ATTEST:
Melissa Boyer, City Clerk
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 1 of 9
Site Specific Conditions of Approval – PD 22-20,
CUP 23-11 and OTR 23-11
Planning Division Conditions:
1. The applicant/developer shall comply with the checked standard Conditions of Approval, “Exhibit B” of Resolution 23-_____.
NOTE: In the event of conflict or duplication between standard and site-specific conditions, the site-specific condition shall supersede the standard condition.
2. The project shall be constructed in substantial conformance with the Conditions of Approval established by Resolution 23-______ and it shall be constructed in substantial conformance with the following Exhibits:
EXHIBITDESCRIPTION
A Site-Specific Conditions of Approval
B Standard Conditions of Approval
C PD Plan Set (AO1.-C4.4)
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 2 of 9
D Arborist Report
3. PD22-20 shall allow for the subdivision, development plan, use permit, and oak tree removal permit to develop an approximate 14-acre site with six (6) commercial/light industrial buildings totaling 240,327 square feet.
4. Approval of this project is valid for a period of two (2) years from date of City Council approval.
Unless construction permits have been issued and site work has begun, the approval of Planned Development 22-20 shall expire on November 7, 2025. The Planning Commission may extend this expiration date if a Time Extension application has been filed with the City along with the fees before the expiration date.
5. The project phasing shall be substantially compliant with the following schedule:
6. Any condition imposed by the City Council in approving this Development Plan and Oak Tree Removal Permit may be modified or eliminated, or new conditions may be added, provided that the Planning Commission shall first conduct a public hearing in the same manner as required for the granting of the original permit. No such modification shall be made unless the Commission finds that such modification is necessary to protect the public interest and/or neighboring properties, or, in the case of deletion of an existing condition, that such action is necessary to permit reasonable operation and use under the Development Plan.
7. OTR23-11 allows for the removal of 6 Valley oak trees (Tree #’s 1, 2, 3, 4, 9 and 11), totaling 270- inches in diameter. Tree No. 10 and 13 shall be protected and subject to the tree preservation details outlined in the Arborist Report, attached as Exhibit S.
8. OTR 23-11 shall require the onsite planting of 67.5-inches in diameter of replacement trees, or 34, 1.5-inch caliper replacement Valley oaks.
9. Before issuance of a building permit, the applicant shall submit a Water Efficient Landscape Worksheet.
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 3 of 9
10. Before final inspection, the applicant shall submit a Certificate of Completion for the landscaping and irrigation installed.
11. Ongoing, the project shall be subject to the City Noise Ordinance.
12. When incorporating new oak trees into your landscape, you will need to allow for at least an 8’ x 8’ planting area. Curbing for the planting area shall not count as part of the planting area dimensions. Planting areas smaller than 8’x 8’ will result in sidewalk and curb buckling when tree roots mature. Distances between oak trees should be no less than 25 feet. If oak trees can be incorporated into open, non-hardscape areas, they will have a higher success rate. Planting trees in groups of 3, in larger landscape planting islands is also a great way to ensure better root health and tree survival rates while maximizing parking lot shade benefits.
13. The following precautions shall be taken to insure protection of Tree No. 10 and 13:
• Do not till or trench within the TPZ to install landscaping or irrigation. • Install only drought tolerant and preferably California native plants beneath the tree canopy.
• Irrigation shall be drip-type and all supply hoses shall be routed above ground. • Do not install overhead sprinkler irrigation because it will introduce too much moisture and potentially rot the tree’s roots.
• Do not install weed block cloth beneath the canopy of the tree. It restricts rainwater from percolating into the soil.
• Provide decorative bark as a top dressing to help retain moisture in the root zone. • Do not construct permanent concrete or brick patios beneath the canopy of the tree. • Install Raised deck patios. They are the preferred treatment for seating areas within the critical root zones of trees.
14. Prior to any construction or ground disturbing activities, the project arborist shall meet with all contractors involved with the development of this project to review tree protection measures.
Any new contractors brought on site shall also meet or communicate with the project arborist by phone or video conference to ensure they are aware of all tree protection measures.
15. If construction occurs during the months of June through November, the TPZs shall be irrigated to a depth of 12 inches 1 time before construction begins, which will ensure the trees are properly hydrated. Additional irrigations during construction may be recommended by the project arborist.
16. All work within or adjacent to the CRZs of oak trees will require arborist supervision to ensure that all tree protection measures are implemented. To avoid damage to critical roots, no machine use will be allowed in the TPZ. In order to prevent undue damage to roots when grading, the grading limits along the perimeter of the TPZ shall be dug by hand to the final grading depth. If a root 1” diameter or larger is exposed, it shall not be cut without the project arborist’s permission.
17. If the project arborist determines that a root over 1-inch diameter needs to be cut, it shall be cut by hand with a pruning saw or reciprocating saw. Once the entire perimeter outside the TPZ has been dug and roots are severed, the project arborist can approve use of machinery to complete excavation and grading if work is outside of the TPZ.
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 4 of 9
18. A tree protection zone or TPZ is similar to a CRZ. Ideally it will be the same size as the CRZ, however it can be smaller. The general rule for CRZ encroachments is that they may be allowed if the impact to critical roots is not more than 25% with no disturbance of Structural Roots (large roots that provide anchorage and stability to the tree).
19. Once the TPZ limits have been established, tree protection fencing shall be provided for all trees listed for protection. Tree protection fencing is required to be in place for the duration of the construction project and shall be installed before starting any ground disturbing activities. • Do not remove any tree protection fencing or enter the TPZ without approval of the project arborist. The fencing shall delineate and protect the tree protection zone. • The fencing shall at minimum, be 4 feet tall and made of orange, high density, polyethylene with 3.5” x 1.5” openings. It shall be installed on steel posts 8 feet on center and tightly stretched to prevent sagging. I STRONGLY recommend installing 6’ X 8’ temporary, chain-link, fence panels secured to driven steel post. This is a more secure and less moveable option than vinyl fencing that can easily be moved by hand or run over by vehicles. See Appendix C - Tree Protection Diagrams & Photos - Diagram 2 – Temporary Chain-link Fence Panel.
• Trunk Protection shall also be provided – Often, the trunk of a tree will be damaged by construction equipment activities. In order to protect as much of the trunk as possible, 2” X 4” wood slats with a minimum height of 8’ shall be placed against the trunk of the tree and secured with wire or zip-ties. DO NOT use anchors such as screws or nails to connect to the trunk. See Appendix C – Tree Protection Diagrams - Diagram 3- Trunk Protection for more detail.
• Tree protection signs shall be placed on the TPZ fencing and be spaced 10 feet apart. Signs shall be weatherproof, and state, “Tree Protection Zone – Do Not Enter”. The signs shall also include the project manager’s and project arborist’s phone numbers. Signs shall remain in place until completion of the project. See Appendix C – Tree Protection Diagrams - Diagram 1 – Tree Protection Fencing for further detail. • No construction or ground disturbance shall be allowed inside the fenced TPZ or CRZ without the project arborist’s permission and/or oversite. If you are unsure whether an activity is allowed, refer to Appendix D - Tree Protection Requirements – Quick Reference List or contact the project arborist Rodney Thurman at 805 234 8760 APCD Conditions:
1. Portable equipment, 50 horsepower (hp) or greater, used during construction activities may require a California statewide portable equipment registration (issued by the California Air Resources Board) or an APCD permit. The following list is provided as a guide to equipment and operations that may have permitting requirements but should not be viewed as exclusive:
• Power screens, conveyors, diesel engines, and/or crushers; • Portable generators and equipment with engines that are 50 hp or greater; • Electrical generation plants or the use of standby generators; • Internal combustion engines; and
• Tub grinders
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 5 of 9
2. Operational sources may require APCD permits. The following list is provided as a guide to equipment and operations that may have permitting requirements but should not be viewed as exclusive:
• New wineries or expanding wineries with the capacity of 26,000 gallons (10,000 cases at twelve 750 milliliter bottles per case) year or more require a Permit to Operate for fermentation and storage of wine;
• Portable generators and equipment with engines that are 50 hp or greater; • Any stationary or portable agricultural engine over 50 hp; • Electrical generation plants or the use of standby generators; • Food and beverage preparation (primarily coffee roasters); • Furniture and fixture products;
• Metal industries, fabrication;
• Small scale manufacturing;
• Boilers;
• Internal combustion engines; and
• Sterilization units using ethylene oxide and incinerators.
3. This project exceeds the ROG+NOx Quarterly Tier 1 threshold; therefore the project’s construction phase shall implement Standard Construction Mitigation Measures:
• Maintain all construction equipment in proper tune according to manufacturer’s specifications;
• Fuel all off-road and portable diesel powered equipment with CARB certified motor vehicle diesel fuel (non-taxed version suitable for use off-road); • Use diesel construction equipment meeting CARB's Tier 2 certified engines or cleaner offroad heavy-duty diesel engines, and comply with the State Off-Road Regulation; • Use on-road heavy-duty trucks that meet the CARB’s 2010 or cleaner certification standard for on-road heavy-duty diesel engines, and comply with the State On-Road Regulation; • Construction or trucking companies with fleets that that do not have engines in their fleet that meet the engine standards identified in the above two measures (e.g. captive or NOx exempt area fleets) may be eligible by proving alternative compliance; • All on and off-road diesel equipment shall not idle for more than 5-minutes. Signs shall be posted in the designated queuing areas and or job sites to remind drivers and operators of the 5-minute idling limit;
• Diesel idling within 1,000 feet of sensitive receptors is not permitted;
4. Projects with grading areas more than 4 acres and/or within 1,000 feet of any sensitive receptor shall implement the following mitigation measures to manage fugitive dust emissions such that they do not exceed the APCD 20% opacity limit (APCD Rule 401) and minimize nuisance (APCD Rule 402) impacts:
a. Reduce the amount of the disturbed area where possible; b. Use of water trucks or sprinkler systems in sufficient quantities to prevent airborne dust from leaving the site and from exceeding the APCD’s limit of 20% opacity for greater than 3 minutes in any 60-minute period. Increased watering frequency would be required whenever wind speeds exceed 15 mph. Reclaimed (non-potable) water should be used whenever possible. When drought conditions exist and water use is a concern, the contractor or builder should consider use of a dust suppressant that is effective for the specific site conditions to reduce the amount of water used for dust control. Please refer to
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 6 of 9
the following link from the San Joaquin Valley Air District for a list of potential dust suppressants: Products Available for Controlling Dust;
c. All stockpiled dirt should be sprayed daily and covered with tarps or other dust barriers as needed;
d. All roadways, driveways, sidewalks, etc. to be paved should be completed as soon as possible, and building pads should be laid as soon as possible after grading unless seeding, soil binders or other dust controls are used;
e. All trucks hauling dirt, sand, soil, or other loose materials are to be covered or should maintain at least two feet of freeboard (minimum vertical distance between top of load and top of trailer) or otherwise comply with California Vehicle Code (CVC) Section 23114; f. “Track-Out” is defined as sand or soil that adheres to and/or agglomerates on the exterior surfaces of motor vehicles and/or equipment (including tires) that may then fall onto any highway or street as described in CVC Section 23113 and California Water Code 13304. To prevent ‘track out’, designate access points and require all employees, subcontractors, and others to use them. Install and operate a ‘track-out prevention device’ where vehicles enter and exit unpaved roads onto paved streets. The ‘track-out prevention device’ can be any device or combination of devices that are effective at preventing track out, located at the point of intersection of an unpaved area and a paved road. Rumble strips or steel plate devices need periodic cleaning to be effective. If paved roadways accumulate tracked out soils, the track-out prevention device may need to be modified; g. All fugitive dust mitigation measures shall be shown on grading and building plans; h. The contractor or builder shall designate a person or persons whose responsibility is to ensure any fugitive dust emissions do not result in a nuisance and to enhance the implementation of the mitigation measures as necessary to minimize dust complaints and reduce visible emissions below the APCD’s limit of 20% opacity for greater than 3 minutes in any 60-minute period. Their duties shall include holidays and weekend periods when work may not be in progress (for example, wind-blown dust could be generated on an open dirt lot). The name and telephone number of such persons shall be provided to the APCD Compliance Division prior to the start of any grading, earthwork, or demolition (Contact the Compliance Division at 805-781-5912).
i. Permanent dust control measures identified in the approved project revegetation and landscape plans should be implemented as soon as possible, following completion of any soil disturbing activities;
j. Exposed ground areas that are planned to be reworked at dates greater than one month after initial grading should be sown with a fast germinating, non-invasive grass seed and watered until vegetation is established;
k. All disturbed soil areas not subject to revegetation should be stabilized using approved chemical soil binders, jute netting, or other methods approved in advance by the APCD; l. Vehicle speed for all construction vehicles shall not exceed 15 mph on any unpaved surface at the construction site;
m. Sweep streets at the end of each day if visible soil material is carried onto adjacent paved roads. Water sweepers shall be used with reclaimed water where feasible. Roads shall be pre-wetted prior to sweeping when feasible; and
n. Take additional measures as needed to ensure dust from the project site is not impacting areas outside the project boundary.
GHG Condition:
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 7 of 9
1. The proposed project would be operational on or before 2028, therefore using the recently released updated guidance from SLO APCD, the applicable threshold should be 740 MT CO2e for operational year 2024, as identified in Table 2 (page 3-12) and Table 1-1 (pages 4-28 and 4-29) of the SLO APCD’s updated guidance document. This GHG threshold for 2028 is also included in the SLO APCD’s land use screening tool. As such, if Central Coast Community Energy is incorporated as a project feature, the GHG impacts would be less than significant when compared to the new thresholds.
a. Prior to the issuance of a final occupancy permit for the Phase 1 building on Lot 13, The applicant commits to the project receiving power from Central Coast Community Energy.
Engineering Division Conditions:
1. The applicant shall offer to dedicate a 30’ right of way for roadway purposes for Ardmore Road from centerline of street across the project northerly frontage. TIMING: Prior to final map recordation
2. The applicant shall provide a 10’ public utility easement on the southerly side of the right of way for Ardmore Road across the project northerly frontage. TIMING: Prior to final map recordation
3. The applicant shall offer to dedicate a 60’ right of way for roadway purposes for Street “A” as shown on the vesting tentative parcel map. TIMING: Prior to prior to final map recordation
4. The applicant shall provide a 10’ public utility easement on both sides of the right of way offered for Street “A”, as shown on the vesting tentative parcel map. TIMING: Prior to final map recordation
5. The applicant shall grant the City an Avigation Easement across all parcels in a form acceptable to the City Engineer. TIMING: Prior to final map recordation
6. Public Storm Drain easements across Lot 13 – Not a part of the tentative parcel Map. TIMING:
Prior to final map recordation
7. Reciprocal drainage easement on northerly side of Lot 13 – Not a part of the tentative parcel Map. TIMING: Prior to final map recordation
8. Reciprocal access easements on the northerly side of Parcel 13 – Not a part of the tentative parcel Map. TIMING: Prior to final map recordation
9. Temporary grading easement on the northerly side of Lot 13 – Not a part of the tentative parcel Map. TIMING: Prior to final map recordation
10. The applicant shall construct Ardmore Road along the northerly project frontage to provide a 40-foot curb to curb section, with sidewalk adjacent to back of curb except at driveway approaches. TIMING: Prior to acceptance of improvements
11. The applicant shall construct Street “A” to provide a 40-foot curb to curb section, with sidewalk adjacent to back of curb except at driveway approaches. TIMING: Prior to acceptance of improvements.
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 8 of 9
12. The applicant shall install public improvements including, but not limited to, curbs, gutters, sidewalks, curb ramps, driveway approaches, streetlights, traffic signage, pavement markings, street signs, and barricades in accordance with City Engineering Standards or as modified on the vesting tentative parcel map. TIMING: Prior to acceptance of improvements.
13. The applicant shall enter into an agreement with the City of Paso Robles to maintain bioretention basins within the Ardmore Road and Street “A” rights of way in perpetuity, as shown on the vesting tentative parcel map. This agreement will be required prior to acceptance of improvements.
14. The applicant shall mitigate additional storm water runoff generated by this project, including off-site improvements. Appropriate drainage facilities shall be designed in accordance with current City Standards. TIMING: Prior to grading final inspection Mitigation Measures – Conditions of Approval:
MM BIO-1: Vegetation removal and initial site disturbance shall be conducted between September 1 and January 31 outside of the nesting season for birds. If vegetation and/or tree removal is planned for the bird nesting season (February 1 to August 31), then preconstruction nesting bird surveys shall be conducted by a qualified biologist to determine if any active nests would be impacted by project construction. If no active nests are found, then no further mitigation shall be required.
If any active nests are found that would be impacted by construction, then the nest sites shall be avoided with the establishment of a non-disturbance buffer zone around active nests as determined by a qualified biologist. Nest sites shall be avoided and protected with the non-disturbance buffer zone until the adults and young of the year are no longer reliant on the nest site for survival as determined by a qualified biologist.
MM BIO-2: To avoid direct take of SJKF during construction in accordance with the CDFW and San Luis Obispo County Guide to SJKF Mitigation Procedures Under CEQA, the project owner shall adopt the Standard Kit Fox CEQA Mitigation Measures and shall be included on development plans. The following measures shall be implemented:
• A maximum 25 mph speed limit shall be required at the project site during construction activities.
• All construction activities shall cease at dusk and not start before dawn. • A qualified biologist shall be on-site immediately prior to initiation of project activities to inspect for any large burrows (e.g., known and potential dens) and to ensure no wildlife are injured during project activities. If dens are encountered, they should be avoided as discussed below. • Exclusion zone boundaries shall be established around all known and potential SJKF dens.
• All excavations deeper than 2 feet shall be completely covered at the end of each working day, or fitted with wildlife escape ramps. • All pipes, culverts, or similar structures shall be inspected for SJKF and other wildlife before burying, capping, or moving.
City Council Agenda November 7, 2023
Exhibit A
Conditions of Approval PD 22-20, CUP 23-11 Page 9 of 9
• All exposed openings of pipes, culverts, or similar structures shall be capped or temporarily sealed prior to the end of each working day. • All food-related trash shall be removed from the site at the end of each workday.
• Project-related equipment shall be prohibited outside of designated work areas and access routes.
• No firearms shall be allowed in the project area.
• Disturbance to burrows shall be avoided to the greatest extent feasible. • No rodenticides or herbicides should be applied in the project area. • Permanent fences between any remaining habitat areas shall allow for SJKF passage through or underneath (i.e., an approximate 4-inch passage gap shall remain at ground level).
• To avoid take of any SJKF and/or active SJKF dens, within 30 days prior to the initiation of site disturbance, implement the SJKF den survey and den closure protocol for unoccupied dens. Any SJKF occupied dens shall be avoided until the SJKF leave the den/site.
• Prior to issuance of grading and/or construction permit and within 30 days prior to initiation of site disturbance and/or construction, all personnel associated with the project shall attend a worker education training program, conducted by a qualified biologist, to avoid or reduce impacts on sensitive biological resources (i.e. San Joaquin kit fox). At a minimum, as the program relates to the kit fox, the training shall include the kit fox’s life history, all mitigation measures specified by the City, as well as any related biological report(s) prepared for the project. The applicant shall notify the City shortly prior to this meeting. A kit fox fact sheet shall also be developed prior to the training program, and distributed at the training program to all contractors, employers and other personnel involved with the construction of the project.
• During the site-disturbance and/or construction phase, any contractor or employee that inadvertently kills or injures a San Joaquin kit fox or who finds any such animal either dead, injured, or entrapped shall be required to report the incident immediately to the applicant and City. In the event that any observations are made of injured or dead kit fox, the applicant shall immediately notify the USFWS and CDFW by telephone. In addition, formal notification shall be provided in writing within three working days of the finding of any such animal(s). Notification shall include the date, time, location and circumstances of the incident. Any threatened or endangered species found dead or injured shall be turned over immediately to CDFW for care, analysis, or disposition.
MM CUL-1 In the event that cultural resources including human remains are encountered during ground disturbance activity, the project shall stop all activity within a 100-foot radius of the find and the project archaeologist shall access the situation with the County Coroner to verify the next steps and determine when construction may resume.
City Council Agenda November 7, 2023
CITY OF EL PASO DE ROBLES
STANDARD DEVELOPMENT CONDITIONS
Development Plan – PD22-20 Conditional Use Permit – CUP 23-14 Tentative Parcel Map Tentative Tract Map VTTM 22-0054
Approval Body: City Council Date of Approval:
Applicant: Covelop/MD3 Location: 2930 Union Road
APN: 025-362-043
The following conditions that have been checked are standard conditions of approval for the above referenced project. The checked conditions shall be complied with in their entirety before the project can be finalized, unless otherwise specifically indicated. In addition, there may be site specific conditions of approval that apply to this project in the resolution.
COMMUNITY DEVELOPMENT DEPARTMENT - The applicant shall contact the Community Development Department, (805) 237-3970, for compliance with the following conditions:
A. GENERAL CONDITIONS – PD/CUP:
1. This project approval shall expire on _TBD_____________unless a time extension request is filed with the Community Development Department, or a State mandated automatic time extension is applied prior to expiration.
2. The site shall be developed and maintained in accordance with the approved plans and unless specifically provided for through the Planned Development and/or Conditional Use Permit process shall not waive compliance with any sections of the Zoning Code, all other applicable City Ordinances, and applicable Specific Plans.
3. To the extent allowable by law, Owner agrees to hold City harmless from costs and expenses, including attorney’s fees, incurred by City or held to be the liability of City in connection with City’s defense of its actions in any proceeding brought in any State or Federal court challenging the City’s actions with respect to the project.
Owner understands and acknowledges that City is under no obligation to defend any legal actions challenging the City’s actions with respect to the project.
4. Any site-specific condition imposed by the City Council in approving this project (PD 22-20) may be modified or eliminated, or new conditions may be added, provided that the Planning Commission shall first conduct a public hearing in the same manner as required for the approval of this project. No such modification shall be made unless the Commission finds that such modification is necessary to protect the public interest and/or neighboring properties, or, in the casof deletion of an existing Exhibit B
City Council Agenda November 7, 2023
condition, that such action is necessary to permit reasonable operation and use for this approval.
5. The site shall be kept in a neat manner at all times and the landscaping shall be continuously maintained in a healthy and thriving condition.
6. All signs shall be subject to review and approval as required by Municipal Code Section 21.19 and shall require a separate application and approval prior to installation of any sign.
7. Prior to the issuance of a Building Permit, a landscape and irrigation plan consistent with the Landscape and Irrigation Ordinance, shall be submitted for City review and approval. The plan needs to be designed in a manner that utilizes drought tolerant plants, trees and ground covers and minimizes, if not eliminates the use of turf. The irrigation plan shall utilize drip irrigation and limit the use of spray irrigation. All existing and/or new landscaping shall be installed with automatic irrigation systems.
8. A reciprocal parking and access easement and agreement for site access, parking, and maintenance of all project entrances, parking areas, landscaping, hardscape, common open space, areas and site lighting standards and fixtures, shall be recorded prior to or in conjunction with the Final Map. Said easement and agreement shall apply to all properties, and be referenced in the site Covenants, Conditions and Restrictions (CC&Rs).
9. All outdoor storage shall be screened from public view by landscaping and walls or fences per Section 21.21.110 of the Municipal Code.
10. For commercial, industrial, office or multi-family projects, all refuse enclosures are required to provide adequate space for recycling bins. The enclosure shall be architecturally compatible with the primary building. Gates shall be view obscuring and constructed of durable materials. Check with Paso Robles Waste Disposal to determine the adequate size of enclosure based on the number and size of containers to be stored in the enclosure.
11. For commercial, industrial, office or multi-family projects, all existing and/or new ground-mounted appurtenances such as air-conditioning condensers, electrical transformers, backflow devices etc., shall be screened from public view through the use of decorative walls and/or landscaping subject to approval by the Community Development Director or his designee. Details shall be included in the building plans.
12. All existing and/or new roof appurtenances such as air-conditioning units, grease hoods, etc. shall be screened from public view. The screening shall be architecturally integrated with the building design and constructed of compatible materials to the satisfaction of the Community Development Director or his designee. Details shall be included in the building plans.
Exhibit B
City Council Agenda November 7, 2023
13. All existing and/or new lighting shall be shielded so as to be directed downward in such a manner as to not create off-site glare or adversely impact adjacent properties.
The style, location and height of the lighting fixtures shall be submitted with the building plans and shall be subject to approval by the Community Development Director or his designee.
14. All walls/fences and exposed retaining walls shall be constructed of decorative materials which include but are not limited to splitface block, slumpstone, stuccoed block, brick, wood, crib walls or other similar materials as determined by the Development Review Committee, but specifically excluding precision block.
16. It is the property owner’s responsibility to ensure that all construction of private property improvements occur on private property. It is the owner’s responsibility to identify the property lines and ensure compliance by the owner’s agents.
17. Any existing Oak trees located on the project site shall be protected and preserved as required in City Ordinance No.835 N.S., Municipal Code No. 10.01 “Oak Tree Preservation”, unless specifically approved to be removed. An Oak tree inventory shall be prepared listing the Oak trees, their disposition, and the proposed location of any replacement trees required. In the event an Oak tree is designated for removal, an approved Oak Tree Removal Permit must be obtained from the City, prior to removal.
18. No storage of trash cans or recycling bins shall be permitted within the public rightof-way.
19. Prior to recordation of the map or prior to occupancy of a project, all conditions of approval shall be completed to the satisfaction of the City Engineer and Community Developer Director or his designee.
20. Two sets of the revised Planning Commission approved plans incorporating all Conditions of Approval, standard and site specific, shall be submitted to the Community Development Department prior to the issuance of building permits.
21. Prior to the issuance of building permits, the
Development Review Committee shall approve the following:
Planning Division Staff shall approve the following:
a. A detailed site plan indicating the location of all structures, parking layout, outdoor storage areas, walls, fences, light fixtures and trash enclosures;
b. A detailed landscape plan;
c. Detailed building elevations of all structures indicating materials, colors, and architectural treatments;
d. Other:
B. GENERAL CONDITIONS – TRACT/PARCEL MAP:
Exhibit B
City Council Agenda November 7, 2023
1. In accordance with Government Section 66474.9, the subdivider shall defend, indemnify and hold harmless the City, or its agent, officers and employees, from any claim, action or proceeding brought within the time period provided for in Government Code section 66499.37, against the City, or its agents, officers, or employees, to attack, set aside, void, annul the City's approval of this subdivision.
The City will promptly notify subdivider of any such claim or action and will cooperate fully in the defense thereof.
2. The Covenants, Conditions, and Restrictions (CC&Rs) and/or Articles Affecting Real Property Interests are subject to the review and approval of the Community Development Department, the Public Works Department and/or the City Attorney.
They shall be recorded concurrently with the Final Map or prior to the issuance of building permits, whichever occurs first. A recorded copy shall be provided to the affected City Departments.
3. The owner shall petition to annex residential Tract (or Parcel Map)________ into the City of Paso Robles Community Facilities District No. 2005-1 for the purposes of mitigation of impacts on the City’s Police and Emergency Services Departments.
4. Street names shall be submitted for review and approval by the Planning Commission, prior to approval of the final map.
5. The following areas shall be permanently maintained by the property owner, Homeowners’ Association, or other means acceptable to the City:
________________________________________________________ ****************************************************************************** ENGINEERING DIVISION- The applicant shall contact the Engineering Division, (805) 237- 3860, for compliance with the following conditions:
All conditions marked are applicable to the above referenced project for the phase indicated.
C. PRIOR TO ANY PLAN CHECK:
1. The applicant shall enter into an Engineering Plan Check and Inspection Services Agreement with the City.
D. PRIOR TO ISSUANCE OF A GRADING PERMIT:
1. Prior to approval of a grading plan, the developer shall apply through the City, to FEMA and receive a Letter of Map Amendment (LOMA) issued from FEMA. The developer's engineer shall provide the required supporting data to justify the application.
2. Any existing Oak trees located on the project site shall be protected and preserved as required in City Ordinance No. 553, Municipal Code No. 10.01 "Oak Tree Exhibit B
City Council Agenda November 7, 2023
Preservation", unless specifically approved to be removed. An Oak tree inventory shall be prepared listing the Oak trees, their disposition, and the proposed location of any replacement trees required. In the event an Oak tree is designated for removal, an approved Oak Tree Removal Permit must be obtained from the City, prior to its removal.
3. A complete grading and drainage plan shall be prepared for the project by a registered civil engineer and subject to approval by the City Engineer. The project shall conform to the City’s Storm Water Discharge Ordinance.
4. A Soils and/or Geology Report providing technical specifications for grading of the site shall be prepared by a Geotechnical Engineer.
5. A Storm Water Pollution Prevention Plan per the State General Permit for Storm Water Discharges Associated with Construction Activity shall be provided for any site that disturbs greater than or equal to one acre, including projects that are less than one acre that are part of a larger plan of development or sale that would disturb more than one acre.
E. PRIOR TO ISSUANCE OF A BUILDING PERMIT:
1. All off-site public improvement plans shall be prepared by a registered civil engineer and shall be submitted to the City Engineer for review and acceptance. The improvements shall be designed and constructed to the City Standard Details and Specifications or as approved by the City Engineer.
2. The applicant shall submit a composite utility plan signed as approved by a representative of each public utility.
3. Landscape and irrigation plans for the public right-of-way shall be incorporated into the improvement plans and shall require approval by the Parks/Facilities Maintenance Supervisor and the Community Development Department.
4. In a special Flood Hazard Area as indicated on a Flood Insurance Rate Map (FIRM) the owner shall provide an Elevation Certificate in accordance with the National Flood Insurance program. This form must be completed by a land surveyor or civil engineer licensed in the State of California.
F. PRIOR TO ISSUANCE OF CERTIFICATE OF OCCUPANCY OR RECORDATION OF THE FINAL MAP:
The Planning Commission has made a finding that the fulfillment of the construction requirements listed below are a necessary prerequisite to the orderly development of the surrounding area.
1. The applicant shall pay any current and outstanding fees for Engineering Plan Checking and Construction Inspection services.
Exhibit B
City Council Agenda November 7, 2023
2. All public improvements are completed and approved by the City Engineer, and accepted by the City Council for maintenance.
3. The owner shall offer to dedicate and improve the following street(s) to the standard indicated:
Street Name City Standard Drawing No.
Ardmore Road Modified A-4
“A” Street Modified A-4
4. If, at the time of approval of the final map, any required public improvements have not been completed and accepted by the City the owner shall be required to enter into a Subdivision Agreement with the City in accordance with the Subdivision Map Act.
Bonds required and the amount shall be as follows:
Performance Bond...............100% of improvement costs.
Labor and Materials Bond........50% of performance bond.
5. If the existing City street adjacent to the frontage of the project is inadequate for the traffic generated by the project, or will be severely damaged by the construction, the applicant shall excavate the entire structural section and replace it with a standard half-width street plus a 12' wide travel lane and 8' wide graded shoulder adequate to provide for two-way traffic.
6. If the existing pavement and structural section of the City street adjacent to the frontage of the project is inadequate, the applicant shall provide a new structural section from the proposed curb to the edge of pavement and shall overlay the existing paving to centerline for a smooth transition.
7. Due to the number of utility trenches required for this project, the City Council adopted Pavement Management Program requires a pavement overlay on _________________ along the frontage of the project.
8. The applicant shall install all utilities. Street lights shall be installed at locations as required by the City Engineer. All existing overhead utilities adjacent to or within the project shall be relocated underground except for electrical lines 77 kilovolts or greater. All utilities shall be extended to the boundaries of the project.
9. The owner shall offer to dedicate to the City the following easement(s). The location and alignment of the easement(s) shall be to the description and satisfaction of the City Engineer:
a. Public Utilities Easement;
b. Water Line Easement;
Exhibit B
City Council Agenda November 7, 2023
c. Sewer Facilities Easement;
d. Landscape Easement;
e. Storm Drain Easement.
10. The developer shall annex to the City's Landscape and Lighting District for payment of the operating and maintenance costs of the following:
a. Street lights;
b. Parkway/open space landscaping;
c. Wall maintenance in conjunction with landscaping;
d. Graffiti abatement;
e. Maintenance of open space areas.
11. For a building with a Special Flood Hazard Area as indicated on a Flood Insurance Rate Map (FIRM), the developer shall provide an Elevation Certificate in accordance with the National Flood Insurance Program. This form must be completed by a lands surveyor or civil engineer licensed in the State of California.
12. All final property corners shall be installed prior to final occupancy.
13. All areas of the project shall be protected against erosion by hydro seeding or landscaping.
14. All construction refuse shall be separated (i.e. concrete, asphalt concrete, wood gypsum board, etc.) and removed from the project in accordance with the City's Source Reduction and Recycling Element.
15. Electronic record drawings, signed by the engineer of record, shall be provided to the City Engineer prior to the final inspection. An electronic autocad drawing file registered to the California State Plane – Zone 5 / NAD83 projected coordinate system, units in survey feet, shall also be provided.
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City Council Agenda November 7, 2023
CITY OF EL PASO DE ROBLES
STANDARD DEVELOPMENT CONDITIONS
Project:
Planning Number: Date:
The following are standard conditions of approval for the above referenced project. The checked conditions shall be complied with in their entirety before the project can be finalized, unless otherwise specifically indicated. In addition, there may be site specific conditions of approval that apply to this project in the resolution. The Project Conditions of Approval do not include all mandatory code requirements. Code compliance will be verified throughout the project which may include additional requirements applicable to your project. Referenced standards include the adopted current code cycle for the California Building Code (CBC), California Fire Code (CFC), Paso Robles Municipal Code (PRMC), and the Paso Robles Standard Details and Specifications.
Applicant shall contact PRFES, (805) 227-7560, for compliance with the following conditions:
G. GENERAL CONDITIONS
1. Prior to the start of construction:
Plans shall be reviewed, approved, and permit issued by PRFES for Underground Fire Line (underground fire line shown on any civil set is for reference only and shall indicate so on each civil page).
Applicant shall provide documentation to PRFES that required fire flows can be provided to meet project demands. Refer to CFC Appendix B.
Exhibit B
Covelop P22-0123 10/04/2023 ✔
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City Council Agenda November 7, 2023
2. Prior to delivery of combustible materials:
Fire hydrants shall be installed and operative to current, adopted edition of the CFC. Refer to CFC Appendix C & CC.
Fire Department Connections (FDC) shall be located on the addressed side of the building and within 150 feet of a fire hydrant, and must not block collector or arterial roadways. Refer to PRMC.
An all-weather access road sufficient to support fire apparatus weighing up to 75,000 lbs. shall be constructed and maintained for the duration of the construction phase of the project. Refer to CFC Appendix D.
Access roads shall be at least 20’ in width with at least 13’ 6” of vertical clearance. All driveway and access roads shall be 10% or less in slope unless approved by PRFES. Refer to CFC Appendix D.
Truck access road shall be minimum 26’ in width with at least 13’ 6” of vertical clearance. Minimum set-back 15’, maximum 30’. Refer to CFC Appendix D.
Provide temporary turn-around for phased construction streets that exceed 150’ in length. Refer to Paso Robles Standard Details and Specifications.
Project shall provide a secondary access fire road approved by PRFES. Refer to CFC Appendix D.
Exhibit B
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