New Development

Post Construction Stormwater Controls
Reduce Pollutants from New Development

Urban development is a major contributor to stormwater-caused pollution. Development or redevelopment of property represents an opportunity to incorporate post-construction controls that can reduce water quality impacts over the life of the project. Since the first countywide municipal stormwater permit was adopted in 1993, the Countywide Program's member municipalities have required new development and redevelopment projects to incorporate post-construction stormwater site design, source control, and treatment measures in their projects to the maximum extent practicable (MEP). To meet the MEP standard, municipalities must employ stormwater control measures that are technically feasible (that is, are likely to be effective) and are not cost prohibitive.

C.3 Stormwater Technical Guidance

The handbook C.3 Stormwater Technical Guidance, Version 3 was designed to help developers, builders, and project sponsors include post-construction stormwater controls in their projects, in order to meet local municipal requirements that reduce the long term impacts of development on stormwater quality and creek channels.

This handbook can be downloaded above as a complete document or by chapters and appendices using the Table of Contents provided below. When using this countywide guidance document, please keep in mind that some requirements may vary from one local jurisdiction to the next. In the very early stages of project planning, contact the local permitting agency to schedule a pre-application meeting to learn how the C.3 requirements will apply to your project. In October 2010, the C.3 Technical Guidance was updated; Version 2 is now available for downloading

TABLE OF CONTENTS

Chapter/ Appendix No.	Section	Title	Last Updated
		Cover Page	12/2011
		Local Contacts and Credits	12/2011
		Table of Contents	12/2011
		Glossary	12/2011
Chapter 1		Introduction/How to Use this Handbook	12/2011
Chapter 2		Background/Regulatory Requirements	12/2011
Chapter 3		Preparing Permit Application Submittals	12/2011
Chapter 4		Site Design Measures	12/2011
Chapter 5		General Technical Guidance for Treatment Measures	12/2011
Chapter 6		Technical Guidance for Specific Treatment Measures	12/2011
	6.1	Bioretention Area (Including Bioretention Swale)	12/2011
	6.2	Flow-Through Planter Box	12/2011
	6.3	Tree Well Filter	12/2011
	6.4	Vegetated Buffer Strip	12/2011
	6.5	Infiltration Trench	12/2011
	6.6	Extended Detention Basin	12/2011
	6.7	Pervious Paving	12/2011
	6.8	Turf Block and Permeable Joint Pavers	12/2011
	6.9	Green Roof	12/2011
	6.10	Rainwater Harvesting and Use	12/2011
	6.11	Media Filter	12/2011
Chapter 7		Hydromodification Management Measures	12/2011
Chapter 8		Operation and Maintenance	12/2011
Chapter 9		Alternative Compliance	12/2011
		References	12/2011
Appendix A		Plant List and Planting Guidance	12/2011
Appendix B		Example Development Scenarios	12/2011
Appendix C		Treatment Measure Design Criteria Regions for San Mateo County	12/2011
Appendix D		Applicability of Inlet Filters, Oil/Water Separators and Hydrodynamic Separators	12/2011
Appendix E		Infiltration Guidelines	12/2011
Appendix F		Mosquito Control	12/2011
Appendix G		Operation and Maintenance Document Templates	12/2011
		Stormwater Treatment Measure O&M Inspection Report Template	12/2011
		Bioretention Area Maintenance Plan Template	12/2011
		Flow-through Planter Maintenance Plan Template	12/2011
		Tree Well Filter Maintenance Plan Template	12/2011
		Vegetated Buffer Strip Maintenance Plan Template	12/2011
		Infiltration Trench Maintenance Plan Template	12/2011
		Extended Detention Basin Maintenance Plan Template	12/2011
		Non-proprietary Media Filter Maintenance Plan Template	12/2011
		Manufactured Stormwater Treatment Measure Maintenance Plan Template	12/2011
Appendix H		Areas Subject to Hydromodification Management Requirements	12/2011
		Countywide Map	12/2011
		Map Index for HM Control in Selected Areas of San Mateo County	12/2011
		Atherton	12/2011
		Brisbane and South San Francisco	12/2011
		Colma and South San Francisco	12/2011
		Daly City and Brisbane	12/2011
		Daly City and County Unincorporated	12/2011
		Millbrae	12/2011
		Millbrae and Burlingame	12/2011
		Pacifica	12/2011
		Pacifica, San Bruno, and South San Francisco	12/2011
		Redwood City and San Carlos	12/2011
		San Bruno and Millbrae	12/2011
		San Mateo	12/2011
		San Mateo and Hillsborough	12/2011
Appendix I		Feasibility Evaluation: Infiltration and Rainwater Harvesting/Use	12/2011
		Feasibility Screening Worksheet	12/2011
		Infiltration Feasibility Worksheet	12/2011
		Rainwater Harvesting and Use Feasibility Worksheet	12/2011
		Attachments to Feasibility Worksheets	12/2011
Appendix J		Special Projects	12/2011
Appendix K		Soil Specifications	12/2011
Appendix L		BMP Specifications for Small Projects	12/2011

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Stormwater Requirements for New Development/Redevelopment:

Flyer: Changes to Stormwater Quality Requirements for Builders, Developers, and Project Applicants updated September 2011.

New Low Impact Development requirements effective December 1, 2011

Impervious Surface Data Collection Worksheet, updated January 2012

C.3 and C.6 Stormwater Compliance Checklist updated September 2011

Feasibility/Infeasibility worksheets to determine the feasibility of infiltrating or havesting and using the water quality design storm volume are in Appendix I of the C.3 Technical Guidance (above).

LID Feasibility Report, Prepared by BASMAA, April 2011

Source Control Model List [word] -updated June 2010

Checklist for NPDES Requirements updated December 2009

Sustainable Green Streets and Parking Lots Design Guidebook

Developments Protecting Water Quality : A Guidebook of Low Impact Development Examples

Hydromodification Management (HM) Requirements

Hydromodification Management Requirements: Information for Developers, Builders and Project Applicants

Hydromodification Management Applicability Form updated May 2010

Link for downloading the Bay Area Hydrology Model software and users manual

Additional Resources and Information

"Start at the Source" Design Guidance Manual for Stormwater Quality Protection (Full version in PDF, sections are broken out below for faster loading)

Cover
Table of Contents, Testimonials, How to Use This Book
Chapter 1 - Introduction
Chapter 2 - Concepts
Chapter 3 - Planning & Zoning
Chapter 4 - Site Design
Chapter 5 - Drainage Systems
Chapter 6 - Site Design and Landscape Details
Chapter 7 - Case Studies
Chapter 8 - Technical Section
Chapter 9 - Next Steps