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 Stormwater Quality Manual for Development Projects in Marin County - Design guidelines and assistance for applicants through the process of submittals and reviews. 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 features in Novato’s Meadow Park subdivision (photo by CSWST2)

Additional Brochures and Guidance

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.

Stormwater Best Management Practice (BMP) Handbooks (revised 2004) - These handbooks have provided excellent guidance to the stormwater community since their publication by the Stormwater Quality Task Force (SWQTF) in 1993. The SWQTF is now known as the California Association of Stormwater Quality Agencies (CASQA) and has revised and updated the Handbooks to reflect current practices, standards, and knowledge gained about the effectiveness of Best Management Practices (BMPs), and has made the Handbooks more accessible.