*NOT YET APPROVED*
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Ordinance No. _____
Ordinance of the Council of the City of Palo Alto Amending Chapter 16.11 (Stormwater PolluƟon PrevenƟon) of Title 16 (Building Standards) of the Palo Alto Municipal Code
The Council of the City of Palo Alto ORDAINS as follows:
SECTION 1. Findings and DeclaraƟons. The City Council finds and declares as follows:
A. Urban Stormwater Runoff is considered a significant pathway for Pollutants into local creeks and the San Francisco Bay (Bay). Rain and irrigaƟon from lawns and gardens wash Pollutants off of Impervious Surfaces like streets, sidewalks, roofs, driveways, and parking lots into Storm Drain Systems and creeks and, ulƟmately, out to the Bay. Water that flows to the Bay from the Storm Drain System and creeks does not receive any treatment and is oŌen Contaminated by Pollutants that can be toxic to fish, wildlife, and people.
B. ProtecƟon of the City of Palo Alto’s Storm Drain System and local Receiving Waters requires strict regulaƟons for Non-Stormwater Discharges and overall adherence to the Municipal Regional Stormwater Permit (“MRP”) issued by the San Francisco Bay Regional Water Quality Control Board (“Regional Water Board”) (Order R2-2022-0018).
C. In order to beƩer protect public health, local Receiving Waters, and the City’s Storm Drain System from Pollutants, the City now desires to update its Municipal Code to consolidate Stormwater compliance management requirements within the same Chapter 16.11 and facilitate compliance with the current MRP .
D. The update of Chapter 16.11 is a component of the City’s Stormwater compliance management program and supports the City’s authority to implement Stormwater and PolluƟon prevenƟon requirements mandated by the Regional Water Quality Control Board.
E. The City desires to maintain and enhance its leadership in protecƟng Stormwater quality by not only meeƟng minimum MRP requirements, but also expanding upon those MRP requirements for certain businesses and Development Projects to further protect local creeks and the Bay.
SECTION 2. Chapter 16.11 (Stormwater PolluƟon PrevenƟon) of Title 16 (Building RegulaƟons) of the Palo Alto Municipal Code is repealed and replaced in its enƟrety to read as follows:
*NOT YET APPROVED*
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Table of Contents
Part 1 Purpose and Intent; DefiniƟons
16.11.010 Purpose and Intent
16.11.020 DefiniƟons
Part 2 General Provisions
16.11.030 AdministraƟon
16.11.040 General ObligaƟon
16.11.050 Conflicts with Other Laws
16.11.060 Alternate Means and Methods
16.11.070 Prohibited Discharges
16.11.080 Discharge ExempƟons
16.11.090 CondiƟonally Exempt Discharges
16.11.100 ProhibiƟon of Illicit ConnecƟons
16.11.110 Authority to Inspect
16.11.120 Enforcement and PenalƟes
16.11.130 Fees and Charges
16.11.140 ObstrucƟon, Damage or Impairment to City Storm Drain System and Rights-of- Way
Part 3 Development Projects
16.11.150 Regulated Projects
16.11.160 Source Control Measures for Regulated Projects
16.11.170 Site Design Measures for Regulated Projects
16.11.180 Stormwater Treatment Measures for Regulated Projects
16.11.190 CerƟficaƟon of Compliance for Regulated Projects
16.11.200 Green Infrastructure Design and ConstrucƟon Requirements
16.11.210 Required HydromodificaƟon Management Measures for Regulated Projects
16.11.220 OperaƟon and Maintenance of Stormwater Treatment Measures and HydromodificaƟon Management Measures
*NOT YET APPROVED*
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16.11.230 Low Impact Development Source Control and Site Design Measures for Projects Other Than “Regulated Projects” Under SecƟon 16.11.150
16.11.240 Requirements for All Development Projects
16.11.250 Requirements for Loading Docks
16.11.260 Drainage Design Standards for Development Projects
16.11.270 Requirements for ConstrucƟon Sites and AcƟviƟes Part 4 Required Best Management PracƟces for All Dischargers
16.11.280 Minimum Best Management PracƟces for All Dischargers Part 5 Illicit Discharge DetecƟon and EliminaƟon and Mobile Sources
16.11.290 Spill Containment and NoƟficaƟon of Non-Stormwater Discharges
16.11.300 Mobile Businesses
Part 5 PesƟcides Toxicity Control
16.11.310 PesƟcides Toxicity Control
Part 6 Trash Load ReducƟons
16.11.320 Trash Load ReducƟons
Part 7 Mercury Controls
16.11.330 Mercury Controls
Part 8 Polychlorinated Biphenyls (PCBs) Controls
16.11.340 Polychlorinated Biphenyls Controls
16.11.350 Management of PCBs During Building DemoliƟon AcƟviƟes Part 9 Copper Controls
16.11.360 Copper Controls
*NOT YET APPROVED*
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Part 1 Purpose and Intent; DefiniƟons
16.11.010 Purpose and Intent
The purpose of this Chapter is to control and limit Stormwater Runoff PolluƟon by prevenƟng Pollutants from entering the City of Palo Alto Storm Drain System and Receiving Waters, including the San Francisco Bay (Bay) and local creeks, marshes, wetlands and other natural habitats, as well as to protect human health and the environment. This Chapter is enacted and shall be implemented in a manner consistent with the Porter-Cologne Water Quality Control Act (Water Code SecƟon 13000 et seq.) and the Federal Clean Water Act (33 U.S.C. SecƟon 1251 et seq.) (CWA), and the requirements of the Municipal Regional Stormwater Permit (MRP) issued by the California Regional Water Quality Control Board, San Francisco Bay-Region 2 (Regional Water Board), as amended from Ɵme to Ɵme. This Chapter is intended to be no less stringent than the MRP and in some respects may be more stringent than regional, state or federal regulaƟons, rules, orders and policies. The City intends to update and modify this Chapter as needed to conƟnue to meet Regional Water Board requirements and provide a program for protecƟon of the Bay and other Receiving Waters. If any provision of this Chapter conflicts with the MRP , as amended or updated, the more stringent and environmentally protecƟve provision shall apply.
16.11.020 DefiniƟons
The following words and phrases, whenever used in this Chapter, shall be as defined herein.
Words and phrases used in this Chapter not otherwise defined in this SecƟon shall be as defined, interpreted or used in the MRP in effect or, if not used in the MRP , so as to give this Chapter its most reasonable applicaƟon.
(a) “A” definiƟons:
(1) “Applicant” means any Person that submits an applicaƟon for a Planning and Land Use EnƟtlement or Building Permit from the City of Palo Alto.
(b) “B” definiƟons:
*NOT YET APPROVED*
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(1) “Best Management PracƟces” or “BMPs” mean a combinaƟon of general good housekeeping pracƟces, PolluƟon prevenƟon and educaƟonal pracƟces, operaƟons and maintenance procedures, and other pracƟces and requirements to prevent or reduce to the Maximum Extent PracƟcable Non-Stormwater Discharges directly or indirectly to the Storm Drain System or Receiving Waters. Sources of industry- standard BMPs include but are not limited to the Santa Clara Valley Urban Runoff PolluƟon PrevenƟon Program, the California Stormwater Quality AssociaƟon Stormwater Best Management PracƟce Handbook, the California Department of TransportaƟon ConstrucƟon Site Best Management PracƟces Manual, and the MRP .
Unless otherwise stated, reference to BMPs generally means non-structural BMPs as described in this definiƟon.
(2) “Building” means any structure used or intended for supporƟng or sheltering any use or occupancy.
(3) “Building Permit” means the authorizaƟon provided by the City to build/construct one or more Buildings.
(c) “C” definiƟons:
(1) “CASQA” means California Stormwater Quality AssociaƟon, a professional member associaƟon dedicated to the advancement of Stormwater quality management through collaboraƟon, educaƟon, implementaƟon guidance, regulatory review, and scienƟfic assessment.
(2) “City” or “The City” means City of Palo Alto, California.
(3) “ConstrucƟon AcƟvity” means any earth- or soil-disturbing acƟvity, including, but not limited to, clearing, grading, paving, landscaping, excavaƟon, stockpiling, material storage, and disturbances to land or ground such as building of a structure, and demoliƟon or removal of structures or paved surfaces.
(4) “ConstrucƟon Site” means any site where ConstrucƟon AcƟvity occurs.
*NOT YET APPROVED*
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(5) “ContaminaƟon” shall have the same meaning as defined in California Water Code SecƟon 13050, as amended from Ɵme to Ɵme.
(6) “ConƟguous” means touching or sharing a border and includes project areas interrupted by cross streets or intersecƟons.
(d) “D” definiƟons:
(1) “Detached Single-Family Home Project” means the building of one single new house or the addiƟon and/or replacement of Impervious Surface to one single exisƟng house, which is not part of a larger plan of development.
(2) “Development Project” means new construcƟon or Redevelopment of any public or private project involving ConstrucƟon AcƟvity and within the planning and building authority of the City.
(3) “Director” means the Director of Public Works of the City of Palo Alto and his or her duly authorized designees.
(4) “Discharge” when used as a verb, means to allow a Stormwater or Non-Stormwater substance to enter the Storm Drain System or a Receiving Water from any acƟvity or operaƟon. When used as a noun, “Discharge” means the Stormwater or Non- Stormwater Discharge that is released or conveyed.
(5) “Discharger” means any Person who causes or permits a Discharge.
(e) “E” definiƟons:
(1) “EPA” or “U.S. EPA” means the Environmental ProtecƟon Agency of the United States of America.
(f) “F” definiƟons:
(1) “Full Trash Capture Device or System” means a treatment control, or series of treatment controls, that traps all parƟcles that are 5 mm or greater and has a design *NOT YET APPROVED*
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treatment capacity that is either: a) of not less than the peak flow rate, Q, resulƟng from a one-year, one-hour storm in the subdrainage area, or b) appropriately sized to, and designed to carry at least the same flows as, the corresponding storm drain.
The device(s) shall also have a trash reservoir large enough to contain a reasonable amount of trash safely without overflowing trash into the overflow outlet between maintenance events.
(g) “G” definiƟons:
(1) “Green Stormwater Infrastructure” or “GSI” means infrastructure that uses vegetaƟon, soils, and natural processes to manage Stormwater Runoff. At the scale of a city or county, GSI refers to the patchwork of natural areas that provides habitat and manages smaller storms, cleaner air, and cleaner water and eliminates street ponding. At the scale of a neighborhood or project site, GSI refers to Stormwater management systems that mimic the natural hydrologic cycle by soaking up and storing water.
(h) “H” definiƟons:
(1) “Hazardous Material” means any material designated as hazardous by Title 17 of this Code.
(2) “Hazardous Waste” means any material designated as a Hazardous Waste by applicable federal, state or local regulaƟons.
(i) “I” definiƟons:
(1) “Illicit ConnecƟon” means any device, arƟfice, method or connecƟon that conveys Non-Stormwater to the Storm Drain System. Examples may include connecƟons from interior floor drains, HVAC systems, industrial processes, sinks, and toilets. An Illicit ConnecƟon does not include methods of conveyance of groundwater during ConstrucƟon AcƟviƟes in compliance with this Code and as approved by the Director. *NOT YET APPROVED*
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(2) “Illicit Discharge” means any Discharge that is prohibited under local, state, or federal statutes, ordinances, codes, or regulaƟons and this Chapter. Illicit Discharges do not include Discharges that are exempt or condiƟonally exempt under the MRP , regulated by a NPDES Permit other than the MRP , or authorized by the ExecuƟve Officer of the Regional Water Board or the Director.
(3) “Impervious Surface” means land that has been modified to reduce or remove the land's natural ability to absorb and infiltrate rainfall. Impervious Surfaces include, but are not limited to, rooŌops, pavement, sidewalks, walkways, paƟos, driveways, and parking lots where such surfaces are not constructed with Pervious materials and/or are not designed to infiltrate Stormwater.
(j) “J” definiƟons:
(1) “Joint Stormwater Treatment Facility” is a Stormwater treatment facility built to treat the combined runoff from two or more Regulated Projects located adjacent to each other.
(k) “K” definiƟons: Reserved
(l) “L” definiƟons:
(1) “Loading Dock” means a raised or lowered area of a facility designed to accommodate a truck, trailer or other large delivery vehicle for the loading and unloading of equipment or materials. A Loading Dock does not include such an area where the deliveries are limited solely to furniture and non-electronic office supplies.
(2) “Low Impact Development” or “LID” is a land planning and engineering design approach with a goal of reducing Stormwater Runoff and mimicking a site’s predevelopment hydrology by minimizing disturbed areas and impervious cover and infiltraƟng, storing, detaining, evapotranspiring, and/or biotreaƟng Stormwater Runoff close to its source, or onsite.
*NOT YET APPROVED*
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(m) “M” definiƟons:
(1) “Mobile Business” means a business whose operaƟons may produce or result in the producƟon of Pollutants and that does not operate from a permanent structure but instead provides mobile services during parƟcular Ɵme periods or upon request at temporary locaƟons. Types of services include cleaning or power washing of vehicles, structures, windows, or parking lots; engine or equipment degreasing; acid cleaning of unpainted trucks or containers; steam cleaning; carpet cleaning; dental and medical care; vehicle repair, servicing, fueling and cleaning; and pet services (including grooming, veterinary care and other miscellaneous services).
(2) “Municipal Code” means the ordinances and laws adopted and enforced by the City of Palo Alto.
(3) “Municipal Regional Stormwater Permit” or “MRP” means the most recently adopted San Francisco Bay Area Municipal Regional Stormwater Permit, a mulƟ- countywide municipal Stormwater NPDES Permit issued by the California Regional Water Quality Control Board, San Francisco Bay Region-Region 2 (Regional Water Board) to regulate Discharges from municipaliƟes and local agencies in Alameda, Contra Costa, San Mateo, and Santa Clara counƟes, and the ciƟes of Fairfield, Suisun City, and Vallejo.
(n) “N” definiƟons:
(1) “Non-Stormwater Discharge” means any Discharge that is not enƟrely composed of Stormwater. Non-Stormwater Discharges include, but are not limited to, polluted groundwater, any Pollutant, Discharges allowed under an NPDES Permit, or an Illicit Discharge.
(2) “NPDES” means NaƟonal Pollutant Discharge EliminaƟon System, which is a naƟonal program for issuing, modifying, revoking and reissuing, terminaƟng, monitoring and enforcing Permits, and imposing and enforcing pretreatment requirements, under SecƟons 307, 402, 318, and 405 of the Federal Clean Water Act.
(o) “O” definiƟons: Reserved
*NOT YET APPROVED*
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(p) “P” definiƟons:
(1) “PCB Screening Assessment” means a report prepared by an Applicant for a demoliƟon Permit containing any informaƟon and data (invesƟgaƟons, reports, soil samples, laboratory results, ConstrucƟon Site controls, etc.) reasonably required by the Director regarding the presence of Polychlorinated Biphenyls (PCBs).
(2) “Permit” means any authorizaƟon issued by the City to carry out an acƟon or acƟvity according to the City’s Municipal Code, rules, and regulaƟons.
(3) “Person” means any individual, partnership, firm, company, corporaƟon, associaƟon, joint venture, joint stock company, trust, estate, governmental enƟty, or any other legal enƟty; or their representaƟves, agents, or designees.
(4) “Pervious” means capable of allowing water to infiltrate below the surface. Pervious materials may include, but are not limited to, permeable interlocking concrete pavers, permeable pavers, Pervious concrete and porous asphalt.
(5) “Planning and Land Use EnƟtlement” means approval provided by the City to develop a Building (or Buildings) or a piece of land for a specific use according to the City’s development standards, rules, and regulaƟons.
(6) "Pollutants” or “Pollutant” means those substances associated with Stormwater Runoff that may cause or contribute to the degradaƟon of water quality of Receiving Waters and are harmful to aquaƟc life, human health and the environment.
Pollutants commonly associated with Stormwater Runoff include, but are not limited to, total suspended solids; sediment; pathogens (e.g., bacteria, viruses, protozoa); heavy metals (e.g., copper, lead, zinc, and cadmium); petroleum products and polynuclear aromaƟc hydrocarbons; syntheƟc organics (e.g., pesƟcides, herbicides, and PCBs); nutrients (e.g., nitrogen and phosphorus ferƟlizers); oxygen-demanding substances (e.g., decaying vegetaƟon and animal waste); liƩer and trash.
*NOT YET APPROVED*
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(7) "PolluƟon" means the presence, introducƟon or Discharge into a Receiving Water of a Pollutant that has harmful or poisonous effects on aquaƟc life, ecological habitat, natural processes of creeks and waterbodies, public health and the environment.
(q) “Q” definiƟons: Reserved
(r) “R” definiƟons:
(1) “Receiving Water” means waters of the State, as defined by the Porter-Cologne Water Quality Control Act. Receiving Waters include but are not limited to creeks, marshes, wetlands, shorelines, estuaries, and bays.
(2) “Redevelopment” means any land-disturbing acƟvity that results in the creaƟon, addiƟon, or replacement of exterior Impervious Surface area on a site on which some past development has occurred. This category includes projects on public or private land that fall under the planning and building authority of the City.
(3) "Refuse" means and includes compostable materials, recyclable materials, and solid waste. Solid waste means solid and semisolid wastes, generated in or upon, related to the occupancy of, remaining in or emanaƟng from residenƟal premises or commercial premises including but not limited to garbage, trash, rubbish, ashes, and industrial wastes.
(4) “Refuse Management and Containment Area” means an area such as a room located inside a Building or an enclosed structure located outdoors to keep, manage and contain compostable, recyclable and solid waste.
(5) “Regional Water Board” or “Water Board” means the California Regional Water Quality Control Board, San Francisco Bay-Region 2.
(6) “Regulated Project” means a project described in Chapter 16.11.150, “Regulated Projects.”
(7) “Remodel” is an extension or modificaƟon of an exisƟng structure. This may include a one or second-story addiƟon that increases the footprint of the structure or an *NOT YET APPROVED*
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interior reconfiguraƟon.
(8) “Responsible Party” means any Person who owns, operates, or manages a property, business, facility, or site, or who is otherwise responsible for the acƟviƟes thereon or the Person whose acƟon or omission causes or results in the violaƟon of this Chapter.
(s) “S” definiƟons:
(1) “Sanitary Sewer System” means the collecƟon system, all sewers, treatment plants and other faciliƟes owned or operated by the City for carrying, collecƟng, storing, treaƟng, reclaiming and disposing of sanitary Sewage and industrial wastes (as defined in SecƟon 16.09.015 of Title 16 of the Palo Alto Municipal Code).
(2) “SCVURPPP” or “Santa Clara Valley Urban Runoff PolluƟon PrevenƟon Program” means an associaƟon of fiŌeen agencies in Santa Clara Valley that share a common NPDES MRP to Discharge to south San Francisco Bay. Member agencies (also referred to as Co-permiƩees) include the ciƟes or towns of Campbell, CuperƟno, Los Altos, Los Altos Hills, Los Gatos, Milpitas, Monte Sereno, Mountain View, Palo Alto, San Jose, Santa Clara, Saratoga, and Sunnyvale, Santa Clara County, and the Santa Clara Valley Water District (Valley Water).
(3) “Sewage” means the wastewater of the community derived from residenƟal, agricultural, commercial, or industrial sources, including domesƟc Sewage, and industrial wastewater, which is required to be conveyed to the Sanitary Sewer System.
(4) “Site Design Measure” means a site planning technique to conserve natural spaces and/or limit the amount of Impervious Surface at Development and Redevelopment Projects in order to minimize runoff and the transport of Pollutants in Stormwater Runoff.
(5) “Source Control Measure” means any BMP that aims to prevent runoff PolluƟon by *NOT YET APPROVED*
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reducing the potenƟal for contact with rainfall runoff at the source of PolluƟon.
Source control BMPs minimize contact between Pollutants and Stormwater Runoff.
(6) “Special Projects” are a type of Regulated Project that meets criteria based on size, land use type, and density per the MRP . These projects are typically located in high density areas and are centered around transit-oriented development. If criteria determined by the MRP are met, projects are enƟtled to incenƟve LID treatment reducƟon credits approved by the Water Board.
(7) “Storm Drain System” means the storm drain faciliƟes owned, managed, or operated by the City by which Stormwater is collected and/or conveyed to Receiving Waters, including but not limited to streets and roads, guƩers, curbs, inlets, piped storm drains, parking lots, pumping faciliƟes, retenƟon and detenƟon basins, natural and human-made or altered drainage channels, reservoirs, and other drainage structures which are within the City’s jurisdicƟon. The Storm Drain System also includes pipes, underground and surface conveyances, and other components on private property and other property within the City’s limits not owned by the City that connect and/or route Stormwater and Stormwater Runoff to the City’s Storm Drain System.
(8) “Stormwater” means any surface flow, runoff, and drainage consisƟng enƟrely of water that originates from precipitaƟon events.
(9) “Stormwater Runoff” means flow that is created when precipitaƟon falls on Impervious Surfaces or compacted Pervious surfaces that do not allow water to infiltrate into the ground.
(10) “Stormwater Run-on” means flow that runs across Impervious Surfaces or compacted Pervious surfaces from one property to another or from one use on a property to another.
(11) “Stormwater Treatment Measure” means any engineered, non-mechanical or constructed system designed to remove Pollutants from Stormwater Runoff by simple gravity seƩling of parƟculate Pollutants, filtraƟon, infiltraƟon, biological uptake, media adsorpƟon or any other physical, biological, or chemical process.
*NOT YET APPROVED*
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(12) “Structural Retrofit Best Management PracƟces” or “Structural Retrofit BMPs” means a retrofit to a structure, fixed feature, or property to prevent or minimize the potenƟal of a Non-Stormwater Discharge to the Storm Drain System or Receiving Waters, in associaƟon with an enforcement acƟon due to noncompliance with this Chapter.
(t) “T” definiƟons: Reserved
(u) “U” definiƟons: Reserved
(v) “V” definiƟons: Reserved
(w) “W” definiƟons: Reserved
(x) “X” definiƟons: Reserved
(y) “Y” definiƟons: Reserved
(z) “Z” definiƟons: Reserved
Part 2 General Provisions
16.11.030 AdministraƟon
The Director shall be responsible for the administraƟon and enforcement of the provisions of this Chapter and has the authority to promulgate such orders, regulaƟons, rules, condiƟons of approval, and requirements as are necessary to accomplish the purposes of this Chapter. The primary regulatory document implemenƟng this Chapter is Palo Alto RegulaƟons for Stormwater PolluƟon PrevenƟon.
16.11.040 General ObligaƟon
All Dischargers of Non-Stormwater and Persons that engage in acƟviƟes with the potenƟal to *NOT YET APPROVED*
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cause a Non-Stormwater Discharge to the Storm Drain System and Receiving Waters shall comply with the provisions of this Chapter. ViolaƟons of regulaƟons implemenƟng this Chapter shall be considered violaƟons of this Chapter.
16.11.050 Conflicts with Other Laws
In the event of any conflict between this Chapter and any federal or state law, regulaƟon, order, or Permit, the requirement that establishes the higher standard for public health or safety shall govern. Nothing in this Chapter shall preclude enforcement of any other applicable law, regulaƟon, order, or Permit. Nothing in this Chapter shall be interpreted to infringe any vested property right.
16.11.060 Alternate Means and Methods
The Director, upon applicaƟon in wriƟng by the owner, a lessee, or an authorized representaƟve of the Discharger, and on noƟce to the Director, is authorized to approve alternate means or methods of compliance with this Chapter, provided that the Director finds that the proposed design, use, or operaƟon saƟsfactorily complies with the intent of this Chapter and that the material, method of work performed, or operaƟon is, for the purpose intended, at least equivalent to that prescribed in this Chapter in quality and effecƟveness in meeƟng the purposes of this Chapter. As required by the Director, an Applicant must show that compliance with the strict requirements of this Chapter is infeasible, and that the proposed alternate means and methods will meet all applicable regional, state, and federal requirements. The parƟculars of any such approval made by the Director shall be in wriƟng and a signed copy shall be furnished to the Applicant.
16.11.070 Prohibited Discharges
General ProhibiƟon. No Person shall cause, allow, or permit any Non-Stormwater Discharge or the condiƟons under which there is a substanƟal probability for such a Discharge to occur unless such Discharge is exempt under SecƟon 16.11.080 or condiƟonally exempt under SecƟon
16.11.090.
*NOT YET APPROVED*
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16.11.080 Discharge ExempƟons
Unless determined by the Director or the Regional Water Board to be sources of Pollutants to Receiving Waters, the following Discharges are exempt from Discharge prohibiƟons established by this Chapter and are allowed to flow into the Storm Drain System and Receiving Waters:
(a) Flows from riparian habitats or wetlands;
(b) Diverted stream flows;
(c) Flows from natural springs;
(d) Uncontaminated rising groundwater due to natural processes;
(e) Uncontaminated and unpolluted groundwater infiltraƟon;
(f) Pumped groundwater from crawl space pumps and foundaƟon and fooƟng drains of single- family homes. Discharges larger than 2,500 gallons per day shall be treated as condiƟonally exempt Discharges and must meet the requirements of the MRP and City regulaƟons;
(g) Pumped groundwater from drinking water aquifers (excluding well development);
(h) Discharges permiƩed under a NPDES Permit issued to the Discharger and administered by the State of California pursuant to Division 7, Chapter 5.5 of the California Water Code, provided that the Discharger is in compliance with all requirements of the Permit and all other applicable laws and regulaƟons; and
*NOT YET APPROVED*
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(i) Any other Discharge exempt from the general prohibiƟon on Discharges to the Storm Drain System under the MRP or permiƩed under another NPDES permit.
If any of the above are idenƟfied by the Director or the Regional Water Board as sources of Pollutants to Receiving Waters, such categories or sources shall be treated as condiƟonally exempt Discharges in accordance with SecƟon 16.11.090.
16.11.090 CondiƟonally Exempt Discharges
The following Discharges are condiƟonally exempt, subject to control measures and BMPs set forth in the MRP and City regulaƟons:
(a) Pumped groundwater, foundaƟon drains, and water from crawl space pumps and fooƟng drains not from single-family homes;
(b) Air condiƟoning condensate shall be reused or directed to landscaped areas. If neither is feasible, Discharging to the Storm Drain System shall be allowed per the Director’s approval;
(c) Discharges associated with water and foam generated from emergency response and/or firefighƟng acƟviƟes. BMPs shall be implemented to the Maximum Extent PracƟcable to minimize potenƟal adverse water quality impacts from water, foam, and other Pollutants Discharged during emergency response and firefighƟng acƟviƟes. Such implementaƟon shall not interfere with immediate emergency response operaƟons or impact public health and safety.
(d) Discharges from individual residenƟal car washing;
(e) IrrigaƟon water, landscape irrigaƟon, and discharges from lawn or garden watering; and
*NOT YET APPROVED*
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(f) Any Discharge that the Director, the local health officer, the Regional Water Quality Control Board or state or federal agency determines in wriƟng is necessary for the protecƟon of the public health and safety, as allowed under applicable law.
16.11.100 ProhibiƟon of Illicit ConnecƟons
(a) No Person shall construct, use, maintain, or permit or suffer the construcƟon, use, maintenance or conƟnued existence of an Illicit ConnecƟon.
(b) Illicit ConnecƟons shall be immediately removed, permanently plugged, or re-plumbed to a connecƟon point approved by the Director.
(c) The provisions of this SecƟon shall apply to, without limitaƟon, Illicit ConnecƟons established in the past, regardless of whether the connecƟon was permissible under law or pracƟces applicable or prevailing at the Ɵme of connecƟon.
16.11.110 Authority to Inspect
(a) The Director shall have the authority to inspect private and public faciliƟes, sites, structures, drainage systems, and Mobile Businesses, whether exisƟng or under construcƟon, whenever necessary to ensure and confirm compliance with this Chapter, applicable City or State regulaƟons, or the MRP .
(b) The Director shall be authorized to enter, without unreasonable delay, and upon reasonable noƟce, any premises subject to the requirements of this Chapter to conduct inspecƟons and monitoring to assure compliance with this Chapter, applicable City or State regulaƟons, or the MRP . An inspecƟon fee shall be charged for each inspecƟon at the amount listed in the City’s Adopted Municipal Fee Schedule. Records related to compliance with this Chapter, including but not limited to operaƟons and maintenance records and agreements, shall be available to City staff for inspecƟon and copying.
*NOT YET APPROVED*
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(c) In the event the owner or occupant of the premises refuses entry aŌer a request to enter and inspect the premises has been made, the City is hereby empowered to seek authorizaƟon from any court of competent jurisdicƟon for such entry.
16.11.120 Enforcement and PenalƟes
(a) ViolaƟons of this Chapter may be enforced as allowed by Title I of the Palo Alto Municipal Code. The Director is authorized to exercise the authority provided in the California Penal Code secƟon 836.5.
(b) The Director may require any Person deemed to have violated this Chapter to take any of the following acƟons:
(1) Ensure that the Discharge be remediated and the affected private and City property and infrastructure, as relevant, be restored within a specified Ɵme. The Responsible Party shall also be responsible for cleanup or reimbursement of cleanup costs incurred by the City for cleanup acƟviƟes associated with any Discharges that violate this Chapter.
(2) Implement applicable BMPs; for example, to address Pollutant sources associated with outdoor process and manufacturing areas; outdoor material storage areas; outdoor waste storage and disposal areas; outdoor vehicle and equipment storage and maintenance areas; outdoor parking areas and access roads; outdoor areas used by customers and employees; outdoor wash areas; outdoor drainage from indoor areas; rooŌop equipment; Contaminated and erodible surface areas; and other sources that have a reasonable potenƟal to contribute to PolluƟon of Stormwater Runoff.
(3) Install Structural Retrofit BMPs to address noncompliance of this Chapter. Structural Retrofit BMPs may require review and approval by the City’s Planning and Building Divisions.
*NOT YET APPROVED*
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(c) The Director shall implement a Stormwater Enforcement Response Plan to facilitate Ɵmely and effecƟve compliance with the requirements of this Chapter. The Enforcement Response Plan shall contain, at a minimum, the following:
(1) Enforcement procedures;
(2) Enforcement tools and scenarios;
(3) Procedures for Ɵmely correcƟon of potenƟal and actual Discharges; and
(4) Procedures for referral and coordinaƟon with other agencies.
(d) The remedies established in this SecƟon are not exclusive. In addiƟon to any other remedies allowed under the Palo Alto Municipal Code, violaƟons may be subject to penalƟes established by resoluƟon of the Council or any other enforcement mechanism allowed by law.
16.11.130 Fees and Charges
The City may adopt reasonable fees and charges for reimbursement of costs of administering and enforcing this Chapter.
16.11.140 ObstrucƟon, Damage or Impairment to City Storm Drain System and Rights-of- Way
Dischargers shall be responsible for and liable to the City for any obstrucƟon, damage, or impairment to the Storm Drain System and other rights-of-way associated with a Discharge that causes an obstrucƟon, damage, or any other impairment to the Storm Drain System. The City *NOT YET APPROVED*
21 0290171_20250418_ms29
may assess a charge against the Discharger to reimburse the City for costs incurred to clean or repair said obstrucƟon, damage or impairment.
Part 3 Development Projects
16.11.150 Regulated Projects
All projects fiƫng the category descripƟons below (hereinaŌer called “Regulated Projects”) must implement Low Impact Development Source Control, Site Design, and Stormwater Treatment Measures. The categories of Regulated Projects are:
(a) New Development Projects or Redevelopment Projects
New Development or Redevelopment projects that create and/or replace 5,000 square feet or more of Impervious Surface (collecƟvely over the enƟre project site). This category includes commercial, industrial, residenƟal housing subdivisions (i.e., Detached Single-Family Home Projects), mulƟ-family aƩached subdivisions (i.e., town homes, condominiums, and apartments), mixed-use, new and reconstructed private roads and private trails, and public projects (other than public road and trail projects), including sidewalks and any other porƟons of the public right-of-way that are developed or redeveloped as part of the projects.
Specific exclusions that apply to this category are listed in SubsecƟon (e) below. Public Works projects that are addiƟonally excluded from this category – unless they create and/or replace 5,000 ConƟguous square feet or more of Impervious Surface – include the following examples:
sidewalk gap closures, sidewalk secƟon replacement, and Americans with DisabiliƟes Act- compliant curb ramps.
Where a Redevelopment project results in an alteraƟon of 50 percent or more of the Impervious Surface of a previously exisƟng development that was not subject to this Part, Stormwater Treatment Measures shall be designed and sized to treat Stormwater Runoff from the enƟre Redevelopment project. Where a Redevelopment project results in an alteraƟon of *NOT YET APPROVED*
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less than 50 percent of the Impervious Surface of a previously exisƟng development that was not subject to this Part, Stormwater Treatment Measures must be designed and sized to treat Stormwater Runoff from the new and/or replaced Impervious Surface of the project.
The calculaƟons in this SubsecƟon shall include porƟons of the public right-of-way that are developed or redeveloped as part of the Regulated Project.
(b) New or Widening Road Projects
Any of the following types of road projects (including both public and private road projects) that create 5,000 square feet or more of newly constructed ConƟguous Impervious Surface, and that fall under the planning and building authority of the City:
(1) ConstrucƟon of new streets or roads, including sidewalks and bicycle lanes built as part of the new streets or roads.
(2) Widening of exisƟng streets or roads with addiƟonal traffic lanes.
Where the addiƟon of traffic lanes results in an alteraƟon of 50 percent or more of the Impervious Surface of an exisƟng street or road within the project that was not subject to this Part, Stormwater Treatment Measures must be designed and sized to treat Stormwater Runoff from the enƟre street or road that had addiƟonal traffic lanes added. Where the addiƟon of traffic lanes results in an alteraƟon of less than 50 percent of the Impervious Surface of an exisƟng street or road within the project that was not subject to this Part, Stormwater Treatment Measures shall be designed and sized to treat Stormwater Runoff from only the new traffic lanes. However, if the Stormwater Runoff from the exisƟng traffic lanes and the added traffic lanes cannot be separated, any onsite treatment system shall be designed and sized to treat Stormwater Runoff from the enƟre street or road. If an offsite treatment system is installed or in-lieu fees paid in accordance with MRP Provision C.3.e or SecƟon
16.11.180(c), the offsite treatment system or in-lieu fees must address only the Stormwater Runoff from the added traffic lanes.
(3) ConstrucƟon of Impervious trails that are greater than or equal to 10 feet wide or are creek-side (within 50 feet of the top of bank).
*NOT YET APPROVED*
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(4) Specific exclusions to this SubsecƟon include the following:
(i) Sidewalks built as part of new streets or roads and built to direct Stormwater Runoff to adjacent vegetated areas;
(ii) Bicycle lanes built as part of new streets or roads, but that are not hydraulically connected to the new streets or roads and that direct Stormwater Runoff to adjacent vegetated areas;
(iii) Impervious trails that direct Stormwater Runoff to adjacent vegetated areas, or other non-erodible permeable areas, preferably away from creeks or towards the outboard side of levees, where those areas are at least half as large as the contribuƟng Impervious Surface area;
(iv) Sidewalks, bicycle lanes, or trails constructed as Pervious pavement systems; and
(v) Caltrans highway projects and associated faciliƟes.
(c) Road ReconstrucƟon and UƟlity Trenching Projects
Road projects that involve the reconstrucƟon of exisƟng streets or roads, which create and/or replace at least one ConƟguous acre of Impervious Surface and that are public road projects and/or fall under the planning and building authority of the City, including sidewalks and bicycle lanes that are built or rebuilt as part of the exisƟng streets or roads. This Regulated Project category includes uƟlity trenching projects which are - on average, over the enƟre length of the project - greater than or equal to eight (8) feet wide. It also includes public pavement maintenance pracƟces listed in SubsecƟon (e)(3) if they are part of a project that otherwise meets the requirements of this secƟon.
Where the reconstrucƟon project results in an alteraƟon of greater than or equal to 50 percent of the Impervious Surface of an exisƟng street or road within the project that was not subject to this Part, Stormwater Treatment Measures must be designed and sized to treat Stormwater Runoff from the enƟre street or road that was reconstructed. Where the reconstrucƟon project results in an alteraƟon of less than 50 percent of the Impervious Surface of an exisƟng street or road within the project that was not subject to this Part, Stormwater Treatment Measures shall be designed and sized to treat Stormwater Runoff from only the new and/or replaced Impervious Surface within the project footprint. However, if the Stormwater Runoff from the exisƟng Impervious Surface and the added Impervious Surface cannot be separated, any onsite treatment system shall be designed and sized to treat Stormwater Runoff from the enƟre street *NOT YET APPROVED*
24 0290171_20250418_ms29
or road. If an offsite treatment system is installed or in-lieu fees paid in accordance with MRP Provision C.3.e or SecƟon 16.11.180(c), the offsite treatment system or in-lieu fees must address only the Stormwater Runoff from the added Impervious Surface.
(d) Large Detached Single-Family Home Projects
Detached Single-Family Home Projects that create and/or replace 10,000 square feet or more of Impervious Surface (collecƟvely over the enƟre project site) and are not part of a larger development or Redevelopment plan regulated under “New Development Projects or Redevelopment Projects” – see SubsecƟon (a) above. This Regulated Project category includes the addiƟon of an accessory dwelling unit (ADU) on an exisƟng parcel with one single-family home that is not part of a subdivision or plan.
Where a single-family home project results in an alteraƟon of 50 percent or more of the Impervious Surface of a previously exisƟng project that was not subject to this Part, Stormwater Treatment Measures shall be designed and sized to treat Stormwater Runoff from the enƟre project. Where a single-family home project results in an alteraƟon of less than 50 percent of the Impervious Surface of a previously exisƟng project that was not subject to this Part, Stormwater Treatment Measures shall be designed and sized to treat Stormwater Runoff from the new and/or replaced Impervious Surface of the project. The calculaƟons in this SubsecƟon shall include porƟons of the public right-of-way that are developed or redeveloped as part of the Regulated Project.
(e) ExempƟons: For Redevelopment projects and Road ReconstrucƟon Projects:
(1) The following interior and exterior pracƟces are excluded:
(i) Interior Remodels; and
(ii) RouƟne maintenance or repair such as roof or exterior wall surface replacement.
(2) The following pavement maintenance pracƟces are excluded:
(i) Pothole and square cut patching;
(ii) Overlaying exisƟng asphalt or concrete pavement with asphalt or concrete without expanding the area of coverage;
(iii) Shoulder grading;
(iv) Reshaping/regrading drainage systems;
(v) Crack sealing;
*NOT YET APPROVED*
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(vi) Pavement preservaƟon acƟviƟes that do not expand the road prism; (vii) Upgrading from a bituminous surface treatment (e.g., chip seal) with an overlay of asphalt or concrete, without expanding the area of coverage; (viii) Applying a bituminous surface treatment to exisƟng asphalt or concrete pavement, without expanding the area of coverage;
(ix) VegetaƟon maintenance; and
(x) Layering gravel over an exisƟng gravel road, without expanding the area of coverage.
(3) The following pavement maintenance pracƟces are not excluded.
(i) Removing and replacing asphalt or concrete pavement to the top of the base course or lower, or repairing the pavement base (including repair of the pavement base in preparaƟon for bituminous surface treatment, such as chip seal), as these are considered replaced Impervious Surfaces; (ii) Extending the pavement edge without increasing the size of the road prism, or paving graveled shoulders, as these are considered new Impervious Surfaces; and
(iii) Resurfacing by upgrading from dirt to gravel, to a bituminous surface treatment (e.g., chip seal), to asphalt, or to concrete; or upgrading from gravel to a bituminous surface treatment, to asphalt, or to concrete, as these are considered new Impervious Surfaces.
(4) For a project consisƟng of a combinaƟon of exempted pavement maintenance pracƟces and non-exempted pavement maintenance and/or pracƟces that fall under any other Regulated Project category, the parts of the project that are not exempt shall be evaluated as a Regulated Project.
16.11.160 Source Control Measures for Regulated Projects
All Regulated Projects shall implement Source Control Measures onsite that, at a minimum, comply with City regulaƟons and the requirements of the MRP .
*NOT YET APPROVED*
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16.11.170 Site Design Measures for Regulated Projects
All Regulated Projects must implement Low Impact Development Site Design Measures that, at a minimum, comply with City regulaƟons and the requirements of the MRP .
16.11.180 Stormwater Treatment Measures for Regulated Projects
All Regulated Projects shall implement Stormwater Treatment Measures onsite that, at a minimum, comply with City regulaƟons and the requirements of the MRP . Stormwater Treatment Measures shall not be altered without permission from the Director.
(a) All Regulated Projects shall design, construct, maintain, and operate Stormwater Treatment Measures for the enƟre duraƟon that the project is in use in accordance with the MRP and City regulaƟons. All Regulated Projects, except Special Projects, shall treat one hundred percent of the amount of Stormwater Runoff idenƟfied in accordance with MRP Provision C.3.c requirements for the Regulated Project’s drainage area onsite or at a Joint Stormwater Treatment Facility per MRP Provision C.3.c, Chapter 16.11.180, and SCVURPPP and City specificaƟons. LID Stormwater treatment measures include harvesƟng and use, infiltraƟon, evapotranspiraƟon, and biotreatment. Stormwater treatment systems must be sized using one of the hydraulic sizing design criteria approved in MRP C.3.d.i. Any Regulated Project that does not comply with this requirement must meet the requirements for alternaƟve compliance established in accordance with SubsecƟon (c) below.
(b) Special Projects designed in a manner that meets the criteria of the MRP and City regulaƟons shall be allowed to apply for IncenƟve LID Treatment ReducƟon Credits per the Water Board’s process outlined in the MRP .
(c) If a Development Project cannot install Stormwater Treatment Measures in conformance with the requirements of the MRP and this chapter, the Director may approve alternaƟve compliance and allow in-lieu measures and/or fees if made necessary by individual site condiƟons and in accordance with the MRP and City regulaƟons. Projects shall sƟll meet all Regulated Project requirements but may be allowed to do so parƟally onsite or fully off-site or through payment of in-lieu fees. This approval shall occur prior to issuance of Planning and Land Use EnƟtlement under Title 18 of this Code, or a Building Permit if no EnƟtlement is required, unless the Director allows an excepƟon.
*NOT YET APPROVED*
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16.11.190 CerƟficaƟon of Compliance for Regulated Projects
(a) Prior to the issuance of a Planning and Land Use EnƟtlement under Title 18 of this Code, or a Building Permit if no EnƟtlement is required, for a Regulated Project, the Applicant or designee of a Regulated Project shall submit a cerƟficaƟon by a qualified third-party reviewer acceptable to the Director that the design of the project complies with the requirements of this Chapter, City regulaƟons, the MRP , and any plan review comments provided by the Director.
AŌer the project is constructed, the Applicant or a designee shall submit a wriƩen cerƟficaƟon by a qualified third-party reviewer acceptable to the Director that a Regulated Project was constructed or installed in accordance with the City-approved plans and drawings and per City regulaƟons and the MRP.
(b) The third-party reviewer shall be an independent civil engineer, licensed architect, or landscape architect registered in the State of California, shall have current training in Stormwater Treatment Measure design and construcƟon, and meet other requirements set forth by the City regulaƟons. The third-party reviewer shall not be any consultant or contractor hired to design and/or construct a Stormwater Treatment Measure for the Regulated Project.
(c) CerƟficaƟons and documentaƟon required by this SecƟon shall be in the form prescribed by the Director.
(d) Applicant is responsible for ensuring that the Stormwater Treatment Measure is constructed according to the design approved by the Director.
16.11.200 Green Infrastructure Design and ConstrucƟon Requirements
Regulated Projects shall comply with applicable design and construcƟon guidelines and standard specificaƟons included in the City’s Green Stormwater Infrastructure Plan and related documents, including design guidelines, standard specificaƟons, and other requirements as established by the Director.
*NOT YET APPROVED*
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16.11.210 Required HydromodificaƟon Management Measures for Regulated Projects
(a) Applicability. All Regulated Projects that result in the creaƟon and/or replacement of one acre (43,560 square feet) or more of Impervious Surface and result in a net increase in Impervious Surface over the pre-project condiƟon shall implement HydromodificaƟon Management Measures.
(b) ExempƟon. Projects located in areas designated as exempt from HydromodificaƟon Management Measure requirements on the HydromodificaƟon Applicability Map contained in the MRP are exempt from this requirement.
(c) HydromodificaƟon Management Measures shall be designed and implemented in accordance with City regulaƟons, MRP requirements, and other applicable regulaƟons and policies.
(d) All HydromodificaƟon Management Measures are subject to inspecƟon and approval by the Director.
16.11.220 OperaƟon and Maintenance of Stormwater Treatment Measures and HydromodificaƟon Management Measures
All Regulated Projects shall comply with the following:
(a) The property owner(s), its administrators, successors, and any other Persons responsible for the management of the property, including any homeowner's associaƟon, shall take all necessary acƟons to ensure that the Stormwater Treatment and HydromodificaƟon Management Measures are properly maintained so that all measures conƟnue to operate as originally designed and approved for the life of the project. These measures shall not be removed, replaced, or amended without the Director’s approval.
(b) Before a Building Permit is issued, a maintenance agreement shall be submiƩed to the Director describing all required Stormwater Treatment and HydromodificaƟon Management Measures, including all informaƟon and documentaƟon required by the Director. This *NOT YET APPROVED*
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agreement shall be approved by the Director, signed by the City AƩorney or designee and property owner(s), and recorded with Santa Clara County. If property changes ownership at any Ɵme, the new property owner(s) shall take on responsibility for maintenance of any Stormwater Treatment and HydromodificaƟon Management Measures located on that property and shall adhere to the operaƟons and maintenance agreement.
(c) The operaƟon and maintenance of the Measures shall at all Ɵmes be conducted in accordance with the terms and condiƟons of the approved maintenance agreement.
(d) Any Stormwater Treatment Measure and/or HydromodificaƟon Management Measure constructed through an alternaƟve compliance opƟon (allowed by the Director per
16.11.180(c)) shall also have a maintenance agreement that complies with this secƟon.
16.11.230 Low Impact Development Source Control and Site Design Measures for Projects Other Than “Regulated Projects” Under SecƟon 16.11.150
Development and Redevelopment Projects that require a Planning and Land Use EnƟtlement or Building Permit from the City but are not Regulated Projects shall implement LID Source Control and Site Design Measures as required by City RegulaƟons and the MRP. The design and implementaƟon of the measures shall be in accordance with the guidelines and technical specificaƟons established by the Director, City regulaƟons, and the MRP . LID features shall not be altered without permission from the Director.
16.11.240 Requirements for All Development Projects
(a) Applicability. This SecƟon shall apply to any Development Project that requires a Planning and Land Use EnƟtlement review or Building Permit, except for minor projects such as those limited to signs, fences, and parking restriping that have no or minimal potenƟal to create Non-Stormwater Discharges.
(b) Development projects shall meet all applicable requirements of the Palo Alto RegulaƟons for Stormwater PolluƟon PrevenƟon and must be designed to accommodate Best Management PracƟces described in SecƟon 16.11.290 and City regulaƟons, as applicable.
*NOT YET APPROVED*
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16.11.250 Requirements for Loading Docks
(a) Applicability. This SecƟon shall apply to any project that includes the construcƟon of a Loading Dock.
(b) The following requirements shall be met for all Loading Docks where applicable:
(1) The Loading Dock and surrounding area shall consist of Impervious paving appropriate for the material(s) that will be loaded/unloaded to avoid leaching into or degradaƟon of paving.
(2) The Loading Dock shall be covered and protected from precipitaƟon, Stormwater Runoff and Stormwater Run-on to minimize potenƟal Non-Stormwater Discharges.
(3) The Loading Dock shall be designed to drain to the Sanitary Sewer System. Drains may be required to be equipped with a fail-safe shut-off valve, normally closed, or equivalent device according to the type of materials or substances being transferred.
Valve shall be immediately shut off if a spill of any size occurs and shall not be opened unƟl the spill is complete remediated.
16.11.260 Drainage Design Standards for Development Projects
(a) All new Development Projects shall meet the requirements of the Public Works Drainage Design Standards and the Santa Clara County Drainage Manual in effect at the Ɵme of submission of a complete planning applicaƟon, or if no planning applicaƟon is required for the Development Project, at the Ɵme of submission of a complete applicaƟon for a Building Permit or excavaƟon and grading Permit, whichever occurs first.
(b) All Redevelopment projects and Remodels requiring a Building Permit or excavaƟon and grading Permit shall meet the requirements of the Public Works Drainage Design Standards provided by the Public Works Director for the porƟon of the site or facility being constructed, Remodeled, or improved.
(c) Notwithstanding the foregoing provisions of this SecƟon, a project shall not be subject to *NOT YET APPROVED*
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the requirements of this SecƟon if the project does not include new drainage paƩerns or alter exisƟng drainage paƩerns of the site.
16.11.270 Requirements for ConstrucƟon Sites and AcƟviƟes
(a) All workers, contractors, subcontractors, and superintendents of ConstrucƟon Sites of any size shall follow and implement all applicable provisions of Stormwater management, PolluƟon prevenƟon, and erosion and sediment control plans and ensure that BMPs are in place to prevent potenƟal Pollutants from being tracked, mobilized, carried, transported, or Discharged into the on-site storm drain inlet(s), City’s right-of-way, Storm Drain System, and Receiving Waters, as required by City regulaƟons.
(b) Projects covered under the State of California ConstrucƟon General Permit (CGP) shall also meet the requirements of this SecƟon. Project Applicants shall provide to the City a copy of the NoƟce of Intent and NoƟce of TerminaƟon required under the CGP .
(c) ConstrucƟon BMPs shall be in place unƟl exterior Impervious Surfaces, the Building shell, landscaping, and Stormwater Treatment Measures are in place. In addiƟon to BMPs generally applicable to ConstrucƟon Sites year-round, all ConstrucƟon Sites shall implement site-specific, seasonally and phase-appropriate BMPs as required by the Director.
(d) The Director is authorized to oversee, inspect, and require expedient compliance with the requirements of this SecƟon at all ConstrucƟon Sites year-round. InspecƟons shall occur at a regular frequency established by the Director.
(e) Contractor/Subcontractor Requirements. The Applicant shall be responsible for ensuring that its contractors and subcontractors comply with this SecƟon.
Part 4 Required Best Management PracƟces for All Dischargers
16.11.280 Minimum Best Management PracƟces for All Dischargers
*NOT YET APPROVED*
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(a) Any Person engaged in acƟviƟes or operaƟons that will or may result in a Non-Stormwater Discharge, or who owns or manages a facility or property where such acƟviƟes or operaƟons occur, shall implement and consistently comply with applicable BMPs outlined in the City regulaƟons.
(b) The Director may require compliance with addiƟonal requirements, including Structural Retrofit BMPs, if necessary, to achieve the purposes of this Chapter.
Part 5 Illicit Discharge DetecƟon and EliminaƟon and Mobile Sources
16.11.290 Spill Containment and NoƟficaƟon of Non-Stormwater Discharges
(a) Any Responsible Party who has knowledge or informaƟon of any known or suspected release of materials, which has resulted in or may result in a Non-Stormwater Discharge other than that permiƩed by this Chapter shall immediately report to the City and take all necessary steps to immediately cease, contain, and clean up the spill using dry clean-up methods. If a Person cannot idenƟfy the spilled material, the Person shall not aƩempt to clean it up in a manner that may result in a Discharge or harm to human health. The Responsible Party shall adhere to the City regulaƟons and any other direcƟon from the Director or other City representaƟve.
(b) If a spill occurs on private property, the Responsible Party shall be responsible for cleaning the private property and any private sanitary or storm drain components located on said property. The Responsible Party shall seek guidance from City staff before cleaning the private sanitary or storm drain components.
(c) The Responsible Party or representaƟve shall not clean any City infrastructure, including any components of the City’s Storm Drain or Sanitary Sewer Systems, without permission from the Director.
(d) The Director shall conduct an invesƟgaƟon and enforcement per the Enforcement Response Plan unƟl the issue is deemed corrected.
*NOT YET APPROVED*
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(e) The Responsible Party and their agents shall adhere to the requirements of Title 17 of this Code with respect to Hazardous Materials and Wastes, and all applicable requirements of the County of Santa Clara and the State of California.
16.11.300 Mobile Businesses
(a) Non-Stormwater Discharges from Mobile Businesses. Mobile Businesses whose acƟviƟes involve the potenƟal Non-Stormwater Discharge shall not allow wash water or any other Non-Stormwater Discharge to Discharge into a storm drain inlet or other component of the Storm Drain System, onto the street, sidewalk, or other paved surface, or directly into a water body. Instead, all wash water and Pollutants shall be disposed of in a cleanout that is connected to the Sanitary Sewer System according to the requirements of the City of Palo Alto Pretreatment Program.
(b) Mobile Businesses shall employ BMPs to prevent Pollutants from Discharging to the Storm Drain System or the Sanitary Sewer Systems without pretreatment, as required by City regulaƟons or otherwise required by the Director.
Part 5 PesƟcides Toxicity Control
16.11.310 PesƟcides Toxicity Control
(a) The Director shall develop, maintain, and implement an Integrated Pest Management Policy and procedures for the use of pesƟcides.
(b) All City employees and contractors shall comply with the Integrated Pest Management Policy and procedures in City operaƟons and on City property.
Part 6 Trash Load ReducƟons
*NOT YET APPROVED*
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16.11.320 Trash Load ReducƟons
(a) Requirements for ExisƟng Businesses. By July 1, 2025, private properƟes that generate moderate, high, or very high trash loads, as defined in City regulaƟons, and that Discharge into private storm drain inlets, shall be equipped with Full Trash Capture Systems or be managed with trash Discharge control acƟons equivalent to or beƩer than Full Trash Capture Systems. Property owners must install and maintain trash capture systems in compliance with City regulaƟons and the requirements of the MRP . Property owners shall be responsible for documenƟng maintenance records per requirements of the City regulaƟons.
Maintenance records shall be made available to the Director upon request.
(b) Requirements for Development Projects. All Development Projects that have operable private storm drain inlets on their property that directly Discharge to the City’s Storm Drain System, any creek, or the San Francisco Bay shall install and maintain Full Trash Capture Devices or systems in compliance with City regulaƟons and requirements of the State Water Resources Control Board.
(c) Full Trash Capture Device or System Maintenance Requirements. Full Trash Capture Devices or Systems shall be maintained by the property owner to ensure that they are operaƟng appropriately and have sufficient operaƟng capacity to capture trash consistent with the MRP and City regulaƟons. The inspecƟon and maintenance of each Full Capture Device shall be at a frequency sufficient to prevent overflow or bypassing of trash and plugging or clogging of screen and device's trash reservoir. Full Trash Capture Devices will be inspected by City staff to ensure compliance.
(d) The private property owner shall be responsible for documenƟng maintenance records per requirements of the City regulaƟons. Maintenance records shall be made available to the Director upon request.
Part 7 Mercury Controls
16.11.330 Mercury Controls
*NOT YET APPROVED*
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(a) The Director shall implement a mercury control program consisƟng of load reducƟon assessment, PolluƟon prevenƟon, Source Control Measures, treatment control measures, Green Stormwater Infrastructure, and measures to reduce risk to consumers of Bay fish.
(b) Source Property IdenƟficaƟon and Abatement. The Director shall invesƟgate and idenƟfy properƟes and land areas that likely contribute mercury to the Storm Drain System and take acƟon to abate or cause abatement of the mercury sources or refer the idenƟfied properƟes to the Regional Water Board for follow-up measures. Source properƟes referred to the Water Board shall implement interim enhanced operaƟon and maintenance measures as required by the Director.
(c) Designated ProperƟes. ProperƟes in industrial areas and in other zones designated in City regulaƟons shall implement treatment control measures, GSI measures, or other control measures to treat Stormwater per the MRP , regional guidance and City regulaƟons.
Part 8 Polychlorinated Biphenyls (PCBs) Controls
16.11.340 Polychlorinated Biphenyls Controls
(a) The Director shall implement a polychlorinated biphenyls (PCBs) control program consisƟng of an assessment methodology and data collecƟon program to idenƟfy and quanƟfy reducƟons of PCB loads in Stormwater through implementaƟon of PolluƟon prevenƟon, Source Control, and treatment control, Green Stormwater Infrastructure, and other measures.
(b) Source Property IdenƟficaƟon and Abatement. The Director shall invesƟgate and idenƟfy properƟes and land areas that likely contribute PCBs to the Storm Drain System and take acƟon to abate or cause abatement of the PCB sources and/or refer the idenƟfied properƟes to the Regional Water Board for follow-up measures. Source properƟes referred to the Water Board shall implement interim enhanced operaƟon and maintenance measures as required by the Director.
(c) Designated ProperƟes. ProperƟes in industrial areas and in other zones designated in City regulaƟons or properƟes otherwise designated by the Director shall implement treatment *NOT YET APPROVED*
36 0290171_20250418_ms29
control measures, GSI measures, or other control measures to treat Stormwater according to the requirements of the MRP , regional guidance, and City regulaƟons.
16.11.350 Management of PCBs During Building DemoliƟon AcƟviƟes
(a) Applicability. This secƟon shall apply to projects that require a DemoliƟon Permit.
DemoliƟons of single-family residences or any wood-framed structures are exempted from this requirement.
(b) PCB Screening Assessment. Any Person undertaking a project that involves the demoliƟon of an enƟre Building constructed or Remodeled between January 1, 1950 and December 31, 1980, inclusive, shall perform a PCB Screening Assessment to determine the presence of PCBs and other hazardous substances at the demoliƟon site and to follow applicable disposal requirements. The PCB Screening Assessment shall be submiƩed prior to issuance of any demoliƟon Permit, in a form and substance prescribed by the Director. The Director may require the PCB Screening Assessment to include any informaƟon reasonably necessary to determine the concentraƟon of PCBs in any primary building materials.
(c) For demoliƟon of Buildings containing materials with PCBs concentraƟons of 50 ppm or greater approved on and aŌer July 1, 2023 idenƟfied per required sampling procedures of this PCBs Program, demoliƟon contractors shall noƟfy the City at least two weeks before any demoliƟon is to occur. Applicant shall determine if addiƟonal agency noƟficaƟon or approvals, or addiƟonal sampling for and abatement of PCBs, is required under other applicable laws. Applicant shall comply with all federal and state laws and regulaƟons, including but not limited to health, safety, and environmental laws and regulaƟons, that relate to management and cleanup of any and all PCBs, including but not limited to PCBs in priority building materials, other PCBs-Contaminated materials, PCBs-Contaminated liquids, and PCBs waste. The requirements of this secƟon do not replace or supplant the requirements of state or federal law, including but not limited to the Toxic Substances Control Act, 40 Code of Federal RegulaƟons (CFR) Part 761, and California Code of RegulaƟons (CCR) Title 22. The demoliƟon contractors shall provide noƟficaƟon to the City if it is determined that advance approval from the U.S. EPA is required. If advance approval to U.S. EPA is not required, then the demoliƟon contractors shall submit a Hazardous Waste manifest for the disposal of the PCBs materials to the City within one week of it becoming *NOT YET APPROVED*
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available. The demoliƟon contractors shall noƟfy the City that the demoliƟon is complete within five business days of compleƟon.
(d) Applicants shall submit wriƩen noƟficaƟons documenƟng any changes in the informaƟon submiƩed in compliance with this secƟon to the Director when changes in project condiƟons affect the informaƟon submiƩed with the Permit applicaƟon.
(e) Applicants shall conduct onsite PCB control measures described in City regulaƟons and as prescribed by the Director.
(f) The Director shall inspect ConstrucƟon Sites during demoliƟon to verify adequate implementaƟon of ConstrucƟon Site controls and proper disposal of PCB-containing materials.
(g) Recordkeeping. Applicants shall maintain documentaƟon of the results of the priority building materials screening assessment for a minimum of five years aŌer submiƩal to the City.
(h) Liability. Applicant is responsible for safely and legally complying with the requirements of this secƟon. Neither the issuance of a Permit under the requirements of the Director or building department, nor the compliance with the requirements of this secƟon or with any condiƟon imposed by the City, shall relieve any Person from responsibility for damage to Persons or property resulƟng therefrom, or as otherwise imposed by law, nor impose any liability upon the City for damages to Persons or property.
Part 9 Copper Controls
16.11.360 Copper Controls
(a) Pools, Spas, and Fountains. Discharges from pools, spas, and fountains that contain copper- based chemicals are prohibited from entering the Storm Drain System. Owners of pools, spas, and fountains shall either install a connecƟon to a private sanitary sewer, including a *NOT YET APPROVED*
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connecƟon for filter backwash, or divert the Discharge for use in landscaping. Discharge diverted for use in landscaping shall not overflow the landscaped area.
(b) Sources. Each industrial source in the City shall have BMPs in place to minimize Discharge of copper to the Storm Drain System, including consideraƟon of roof runoff that might accumulate copper deposits from venƟlaƟon systems on site.
(c) Roofing Materials. Copper metal roofing, copper granule containing asphalt shingles, and copper guƩers shall not be permiƩed for use on any residenƟal, commercial, or industrial Building for which a Building Permit is required. Copper flashing for use under Ɵles or slates and small copper ornaments are exempt from this prohibiƟon. Replacement roofing and guƩers on historic structures are exempt, provided that the roofing material used shall be pre-paƟnated at the factory. For the purposes of this exempƟon, the definiƟon of "historic" shall be limited to structures designated as Category 1 or Category 2 Buildings in the current ediƟon of the Palo Alto Historical and Architectural Resources Report and Inventory.
(d) Sites requiring copper controls shall comply with all applicable BMPs described in City regulaƟons and otherwise prescribed by the Director.
SECTION 3. If any SecƟon, SubsecƟon, clause or phrase of this Ordinance is for any reason held to be invalid, such decision shall not affect the validity of the remaining porƟon or SecƟons of the Ordinance. The Council hereby declares that it would have adopted the Ordinance and each SecƟon, SubsecƟon, sentence, clause or phrase thereof irrespecƟve of the fact that any one or more SecƟons, SubsecƟons, sentences, clauses or phrases be declared invalid.
SECTION 4. The Council finds that this project is exempt from the provisions of the California Environmental Quality Act (“CEQA”), pursuant to SecƟon 15308 of the CEQA Guidelines, because it is an acƟon taken by the City as a regulatory agency to assure the maintenance, restoraƟon, enhancement, or protecƟon of the environment where the regulatory process involves procedures for protecƟon of the environment.
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*NOT YET APPROVED*
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SECTION 5. This ordinance shall be effecƟve on the thirty-first day aŌer the date of its adopƟon.
INTRODUCED:
PASSED:
AYES:
NOES:
ABSENT:
ABSTENTIONS:
ATTEST:
____________________________ ____________________________ City Clerk Mayor
APPROVED AS TO FORM: APPROVED:
____________________________ ____________________________ City AƩorney or Designee City Manager
____________________________
Director of Public Works