Loading...
HomeMy WebLinkAbout(2002, 04/23) - L-22 - AdoptedPROTECTION OF WATER QUALITY: WATER QUALITY MANAGEMENT PLANS FOR NEW DEVELOPMENT AND REDEVELOPMENT PURPOSE L -22 This policy, along with Policy L -18, is intended to minimize dry - weather runoff and runoff from small rain events (collectively referred to as "runoff' in this Policy) in an effort to improve water quality of Newport Bay, water quality- limited receiving waters like Buck Gully) and the near -shore ocean environment. The motivation for this Policy, in addition to the community's interest in clean water, is in part the adoption of new regulations upon the City of Newport Beach by the California Regional Water Quality Control Board, Santa Ana Region ( "Regional Board ") contained in the Regional Board's Order # R8- 2002 -0010, NPDES No. CAS618030. FINDING Runoff from irrigation overspray, overwatering, roof drains, patio and deck drains, and washdowns of hardscape areas contribute flow to the street drainage systems and natural watercourses which then convey pollutants such as pesticides, fertilizers, pet waste, oil, engine coolant, gasoline, hydrocarbons, brake dust, tire residue, and other pollutants into surface waters. POLICY New development or redevelopment presents the City and the public with the opportunity to reduce the impacts of runoff that would otherwise drain to the City's street drainage system and our harbors, bays, and ocean. At the time of submittal of an application for a new development or redevelopment project, an applicant shall submit a Water Quality Management Plan (WQMP) to the City. The WQMP's purpose is to minimize to the maximum extent practicable dry weather runoff and runoff from small storms (less than 3/4" of rain falling over a 24 -hour period) during construction and post - construction from the property. The following are components of any WQMP: A. Design Elements — All Development Types. Each applicant's WQMP shall attempt to infiltrate or treat projected runoff for the new development by an amount equal to or greater than the volume of runoff produced from a storm event through incorporation of design elements that address one or more of the goals set forth below. The design elements utilized by an applicant may, but are 1 L -22 L J not required to, include those provided on the list below so long as the required projected runoff infiltration or treatment is achieved: 1. Maximize permeable areas to allow more percolation of runoff into the ground through such means as biofilters, green strips, landscaped swales, planters, and other retention/ percolation devices as approved. The use of permeable materials in lieu of or to replace hardscapes will increase the amount of runoff seepage into the ground. 2. Maximize the amount of runoff directed to permeable areas and /or maximize stormwater storage for reuse or infiltration. For the purposes of this Policy, pools, spas, and water features shall not be considered permeable surfaces. Acceptable and encouraged design elements include: a. Orienting roof runoff towards permeable surfaces, drywells, French drains, or other structural BMPs rather than directly to driveways or non - permeable surfaces so that runoff will penetrate into the ground instead of flowing off -site. • b. Grading the site to divert runoff to permeable areas. C. Using cisterns, retention structures or green rooftops to store precipitation or runoff for reuse. d. Removing or designing curbs, berms or the like so as to avoid isolation of permeable or landscaped areas. e. Remove pollutants through installation of treatment control BMPs such as filters, clarifiers, and other devices as approved. B. Design Elements — Commercial, Retail, and Multi- Family Residential. These design elements shall be required for all new development except single- family residences: 1. Urban runoff shall not be allowed to come into contact with the following areas: Loading and unloading dock areas; • 2 L -22 Repair and maintenance bays; Vehicle and equipment wash areas; and Fueling areas. 2. Where new development/ redevelopment will include outdoor areas for the storage of material that may contribute pollutants to the storm water conveyance system, these materials must be: Placed in an enclosure such as, but not limited to, a cabinet, shed, or similar structure that prevents contact with runoff or spillage to the storm water conveyance system; or Protected by secondary containment structures such as berms, dikes, or curbs. 3. The outdoor materials storage areas subject to this section must be: Paved and sufficiently impervious to contain leaks and spills; and Covered with a roof or awning to minimize collection of storm water within the secondary containment area. 4. The area where a trash receptacle or receptacles are located for use as a repository for solid wastes must meet the following structural or treatment control BMPs: Drainage from adjoining roofs and pavement must be diverted away from the trash storage areas; The area must be covered with roof or awning (to prevent rain from entering the area and sewer or storm drain conveyance system), screened or walled to prevent off -site transport of trash, and connected to the sanitary sewer; and Trash bins must have solid covers and be covered at all times except while being emptied. 5. Any construction project adding down spouts, gutters and subsurface pipes directing stormwater to the curb face shall have a French drain system of perforated pipe and gravel unless site - specific circumstances endanger public safety so as to prohibit its use as determined by the Building Department or Public Works Department. 0 3 L-22 • C. Use of Moisture - Detecting or Weather -Based Irrigation Systems. All WQMPs must describe how the applicant plans to use irrigation systems that are automated and controlled by either a weather -based satellite system or by direct moisture detection in the soil. D. Long -Term Maintenance. The WQMP must also include the applicant's plan for the long -term and continuous maintenance of all BMP's requiring ongoing maintenance and the applicant's signed statement accepting responsibility for the maintenance of all structural and treatment control BMPs. Any transfer or sale of property subject to a Water Quality Management Plan must include as a written condition to the transfer or sale such that the transferee assumes full responsibility for maintenance of any structural, and /or source or treatment control BMPs. E. Evaluation of WQMPs. The City's evaluation of each Water Quality Management Plan will ascertain if the proposed plan meets the standards set forth in this Policy. Each plan will be evaluated on its own merits according to the particular characteristics of the project and the site to be developed. The Building Director or Public Works Director, or their respective designee shall • approve or disapprove the plan. If the plan is disapproved, the reasons for disapproval shall be given in writing to the applicant. Any plan disapproved by the Building Director or Public Works Director or their respective designee must be revised by the developer and resubmitted for approval. No building permit shall be issued until the final WQMP has been approved by the Building Department or Public Works Department. F. Waiver. The WQMP required under this Policy may be waived by the Building Director or Public Works Director or his or her designee if the applicant demonstrates the impracticability of implementing this Policy's requirements. Recognized circumstances demonstrating impracticability may include: 1. Extreme limitations of space for treatment; 2. Unfavorable or unstable soil conditions at a site to attempt infiltration; and 3. Risk of groundwater contamination because a known unconfined aquifer lies beneath the land surface or an existing or potential underground source of drinking water is less than ten feet from the soil surface. 4 • MRIJ Any other justification for impracticability must be separately petitioned by the applicant to the City Manager and, where applicable, the California Regional Water Quality Control Board for advice and consideration. If a waiver is granted for impracticability, the petitioner will be required to transfer the savings in cost, as determined by the Building Director or Public Works Director, to the City's Runoff Mitigation Account. This Account shall be used to promote regional or alternative solutions for runoff pollution in Newport Beach -area watersheds. Funds payable from the Account may accrue to a public agency or a non -profit entity. G. Compliance Required. Compliance with an approved Water Quality Management Plan shall be a condition of any required planning approval. Adopted - April 23, 2002 0 5