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New Stormwater Regulations “C. 3” Provisions in effect Feb. 15, 2005
Protecting Water Quality 1. 2. 3. 4. Why managing stormwater is important. What we are doing now. How new development affects water quality. How the new regulations will be implemented.
What is a watershed?
Managing Stormwater Runoff Ø Preventing Stormwater Pollution l l l Toxic pollutants like mercury and PCBs Sediment, oil and grease Household pesticides and detergents
Managing Stormwater Runoff Ø Preventing Stormwater Pollution l l l Toxic pollutants like mercury and PCBs Sediment, oil and grease Household pesticides and detergents Ø Quantity and timing of runoff l l Paved, impervious roofs, parking, and streets Increased volume of flow and peak flow rate.
Who is involved? Ø Stormwater management activities are coordinated throughout City departments. Ø City participates in and cooperates with the Contra Costa Clean Water Program. l CCCWP includes 18 other Contra Costa cities and towns, Contra Costa County, and the Flood Control District. Ø Oversight by the California Regional Water Quality Control Board (SF Bay Region).
What the City is Doing Now Ø Complies with storm water discharge permit. Ø Inspects businesses. Ø Minimizes pollutants from City activities. Ø Contributes to monitoring & pollutionprevention studies. Ø Conducts outreach and education.
Municipal Stormwater NPDES Permit History § 1994: First countywide permit issued. Focus on public outreach and education. § 1999: Permit revised, added performance standards for implementation § February 2002: Revised Permit Provision C. 3. (New and Redevelopment Requirements)
Effects of New Development
Runoff Before Development
Runoff After Development
Effects of increased runoff Increased flows and more frequent flooding leads to… Ø Increased streambank erosion, which leads to… Ø “Hardening” to prevent erosion, which leads to… Ø
Loss of Stream Functions
Solutions Design areas that allow runoff to infiltrate into soil. Ø Use pervious paving. Ø Integrate shallow detention basins into landscaping. Ø Use narrower streets; minimize impervious surface area. Ø
Vegetated (“Dry”) Swale
New Regulations for Development and Redevelopment § Provision C. 3. Requirements: § Projects (public & private) must detain or treat runoff on site. § Projects with 1 acre or more impervious surface approved after February 15, 2005 § Projects with 10, 000 square feet or more impervious surface approved after Oct. 2006 § Mandated design criteria for volume and flow
Cities, towns & County must: § Estimate and control future increases in peak runoff § Verify that on-site treatment devices are maintained § Update conditions of approval, design standards, General Plans, & environmental review processes
Contra Costa’s Approach Clean Water Program (Cities, Towns, County, CCFCWCD) Management Committee C. 3 Oversight Committee Planning & Permitting Work Group Technical Work Group Legal Work Group C. I. P. Work Group
Preparations for C. 3 Ø Update to Model Stormwater Ordinance Ø Stormwater C. 3 Guidebook l l Require a Stormwater Control Plan for planning and zoning review Show drainage from site will be routed through treatment facilities Ø Memos on technical and policy issues Ø Workshops for staff and applicants
C. 3 & Development Review Pre-Application Meeting Planning Commission Detailed Design Completed Application Conditions of Approval Plan Check “Deemed Complete” Section Review CEQA Review Permits to Build
Stormwater C. 3 Compliance Pre-Application Meeting Completed Application Section staff may review “Deemed Stormwater Complete”Control Plan along with site, grading, landscaping Sectionand other plans Review Does applicant’s Stormwater Control Plan address all req’ts? Planning Conditions of Commission Approval CEQA Stormwater Review Control Plan is attached to COAs Permits Detailed Plan Check to Staff reviews Design Build implementation of Plan in drawings & specs Staff identifies general C. 3 requirements
Operation & Maintenance General description of O&M requirements Stormwater Control Plan Submitted with Planning & Zoning Application Detailed description and maintenance plan for each facility Certification of inspection & continued operation Stormwater Facilities Operation & Maintenance Plan Stormwater Facilities Compliance Certificate Draft submitted with construction documents Renewed each year
Stormwater Control Plan Contents Project Setting Ø Measures to Limit Imperviousness Ø Selection & Design of Treatment BMPs Ø Source Control Measures Ø Permitting and Code Compliance Ø BMP Maintenance Ø Construction Plan C. 3 Checklist Ø Certification Ø
More Information Ø Quick Summary l Ø Summary of Project Review Process l Ø Stormwater C. 3 Regulations Fact Sheet (4 pages; includes checklist) Stormwater C. 3 Guidebook l Ø Stormwater Quality Control for Development Projects (2 -page fact sheet) Overview and step-by-step instructions for preparing a Stormwater Control Plan Guidebook Appendices and References l With hyperlinks to design and technical resources