New and Redevelopment Projects/Attachment 4

The following resources are primarily intended for development project applicants, architects, engineers, contractors, planners, and municipal staff.

Stormwater requirements for new developments were tightened in 2003. Marin municipalities must now comply with specific requirements and standards in the State National Pollutant Discharge Elimination System (NPDES) permit covering small municipal seperate storm sewer systems throughout California (Phase II permit). Most requirements under the permit were phased in from 2003-2008.

The “Attachment 4” requirements are separate from, and in addition to, requirements for erosion and sediment control and for pollution prevention measures during construction. Attachment 4 requirements are being fully phased in through 2008. Projects in Novato, San Rafael, and unincorporated areas must implement the design standards in Attachment 4 to the permit. MCSTOPPP developed a guidance manual, “Guidance for Applicants: Stormwater Quality Manual for Development Projects in Marin County” to assist project applicants to prepare submittals that demonstrate their project complies with the NPDES permit requirements. Other Marin municipalities may require project applicants to follow this guidance as part of their required program to implement new development controls.

For more information on stormwater requirements for development projects in Marin County please refer to the Stormwater Ordinances page.

Guidance and Fact Sheets: Meeting Attachment 4 Requirements in Marin County Attachment 4 Fact Sheet - Outlines requirements for development projects regarding permanent stormwater controls for treating stormwater runoff and retaining pre-project peak runoff flows. Stormwater Quality Manual for Development Projects in Marin County - Design guidelines and assistance for applicants through the process of submittals and reviews. Using Bioretention on Residential Lots - How to incorporate bioretention facilities into residential lots including how to calculate sizing. Stormwater Control Plan Template - A draft template to start your plan. More Marin County Guidance: Post-Construction Stormwater Control Protecting Water Quality in the Northern San Francisco Bay Area (August 2005) - A Guidebook of Post-Construction Stormwater Best Management Practices in Action. Creating Pervious Surfaces for New Development and Redevelopment - A guide for Surface Water Pollution Control and Best Management Practices. Green Building - A Marin County Community Development Agency website with links about Energy and Green Building.

Low Impact Development rain garden feature at Branson School, Ross (photo by Christopher Lemon)

Additional Brochures and Guidance

Blue-Green Building - Water Friendly Development in the East Bay

Construction Best Management Practice (BMP) Handbook/Portal (revised 2009) - This 2009 update of the Construction Handbook reflects the current state of construction stormwater quality management practices and revised regulatory requirements. Provided by the California Association of Stormwater Quality Agencies (CASQA), the handbook/portal reflects current practices, standards, and knowledge gained about the effectiveness of Best Management Practices (BMPs). Overall the information in the Construction Handbook has been updated and reorganized. Hyperlinks have been provided throughout the handbook/portal and in the References and Resources section to direct users to additional information.

LID - A Sensible Approach to Land Development and Stormwater Management

Start at the Source (1999) - This manual focuses on the importance of considering stormwater quality in the early stages of planning and designing land development and redevelopment projects. This edition includes important information on commercial, industrial, and institutional development, as well as a technical section to provide more detailed information on the characteristics, applications, design criteria, maintenance, and economics of the details that are discussed in this document. Examples of case studies, frequently asked questions, and a complete glossary are also included.

Using Site Design Techniques to Meet Development Standards for Stormwater Quality (May 2003) - A Companion Document to Start at the Source.

Qualified Stormwater Management Consultants - The Bay Area Stormwater Management Agencies Association (BASMAA) list of qualified consultants specializing in post-construction stormwater treatment facility design and installation, and urban stormwater management practices, issues, and requirements.

Think Blue Marin - New Pilot Programs from the Marin Municipal Water District feature Rainwater Harvesting and Community Conservation.

Porous Pavements

Low Impact Development Techniques: Pervious Pavement - Information provided by the UC Davis Extension on porous grass or turf pavers, gravel pavers, open joined and open cell paving blocks, porous cement, and porous asphalt.

Porous Asphalt Pavements - Information on porous asphalt pavement, commonly known as open graded asphalt concrete (OGAC), open graded friction course (OGFC), and permeable asphalt, provided by the California Asphalt Pavement Association.