New and redevelopment projects should be designed to prevent water quality impacts from occurring, not just during construction, but throughout the life of the project.
Post-Construction Requirements
In July, 2013, the Central Coast Water Board adopted Order R3-2013-0032, with new, more stringent Post-Construction Requirements (PCRs). Projects that receive their first discretionary approval for design elements after March 6, 2014 — or, if no discretionary approval is required, receive their first ministerial permit after that date — are subject to the PCRs, if they create or replace 2,500 square feet or more of impervious area.
Stormwater Technical Guide
Applicants for development approvals in jurisdictions within the Monterey Regional Stormwater Management Program should use the Stormwater Technical Guide when preparing Stormwater Control Plans. However, local requirements vary. Check with staff in the jurisdiction where your project is located to identify differences that may apply. A pre-application meeting is recommended for all projects subject to the PCRs.
- Stormwater Technical Guide
- Stormwater Control Plan Template
- Stormwater Control Plan Template – Small (Tier 1) Projects
- Appendix A: Source Control
- Appendix B: Bioretention Construction Checklist
- Appendix C: Technical Criteria for Non-LID
- Stormwater Control Measures Sizing Calculator
- Sizing Calculator Instructions
- Watershed Management Zone Maps
- Presentation slides regarding the Stormwater Technical Guide are available here. A recording of a similar presentation that occurred in Santa Maria, CA, is available here.
Requirements at a Glance*
* These thresholds, along with a project’s Watershed Management Zone (WMZ) designation, determine the specific requirements applicable for project determination.
** Net impervious surface equals new and replaced impervious area minus the total pre-project-to-post-project reduction in impervious area (if any).
Additional Resources:
Operations and Maintenance Plan: This plan is an actual Operation & Maintenance Plan prepared for a residential subdivision in Contra Costa County. This is an example only. Contents tend to be project-specific in accordance with the Stormwater Control Plan and should be discussed with your Municipal contact. Information on how to prepare an Operation & Maintenance Plan is provided in Chapter 5 of the Stormwater Technical Guide.
Infiltration Rate Assessment Methods: This manual from the County of San Diego provides useful guidance for the Geotechnical Engineer Analysis.
Infiltration Testing: This manual from the Riverside Flood Control District provides useful guidance on infiltration testing.
Bureau of Reclamation Drainage Manual: This manual from the U.S. Bureau of Reclamation offers guidance for integrating plant, soil, and water relationships for drainage of irrigated lands.
Links:
Environmental Protection Agency’s (EPA) Low Impact Development (LID) Website
Central Coast Stormwater Program
California Stormwater Quality Association (CASQA) California LID Portal
Central Coast Low Impact Development Initiative Technical Guidance Web Site
Videos:
Storm Drain (English)
Storm Drain (Spanish)