Types of development and redevelopement that must include measures to prevent degradation of surface water quality include:

1. Residential subdivisions with 10 or more dwelling units.
2. Commercial development of 0.5 acres or greater.
3. Parking lots of 5,000 square feet or more or that have 25 or more parking spaces and are
    potentially exposed to storm water runoff.
4. Automobile repair shops.
5. Retail gasoline outlets.
6. Restaurants.
7. Single-family residences located on slopes of 20 percent or greater.
8. Any new development or redevelopment exceeding one acre.

If the development or redevelopement falls under any of these categories, proceed to steps 2 and 3.

For purposes of implementing these regulations, redevelopment is defined as follows:
Redevelopment means, on an already developed site, the creation or addition of at least 5,000 square feet of impervious area. Redevelopment includes, but is not limited to: the expansion of a building footprint or addition of a structure; structural development including an increase in gross floor area and/or exterior construction or remodeling; and land disturbing activities related with structural or impervious surfaces. Where redevelopment results in an increase of less than fifty percent of the impervious surfaces of a previously existing development, and the existing development was not subject to these Design Standards, the Design Standards apply only to the addition, and not to the entire development.
(Attachment 9 to WQO 2003-0005-DWQ)

In order for an application for one of the above projects to be deemed complete, the submittal must identify how runoff will be treated for design storm using an acceptable BMP approach (see below for acceptable guidance documents).

Example calculations for "application completeness"

 
Step 2: Select Source Control and Site Design Measures

Attachment 4(B) lists the minimum required measures including those that are activity-specific (i.e., proper design of fuel dispensing stations), and those that are more general (eg., reduce overall imperviousness of parking areas).

During Step 2, staff from Planning & Development, Development Review will look for anticipated pollutants that could be generated from the development and measures to minimize contribution of pollutants. Early discussion between engineer, architect, and landscape architect is key to retaining and infiltrating storm water onsite. These measures must be included to reduce the duration/intensity/volume of runoff from developed areas. Using Low Impact Development measures, your project can integrate the required source control and site design measures in Step 2, and treatment control measures described in Step 3.		Integrating Low Impact Development measures addresses required site design requirements AND reduces the runoff to be treated in Step 3! Click here for more information on LID For regulatory information and training opportunities from the Central Coast Regional Water Quality Control Board click here
Staff from Planning & Development, Development Review, will look for anticipated pollutants that could be generated from the development and measures that minimize contribution of pollutants. The Water Environment Research Foundation has developed resources to guide you through the principles and practices of sustainable stormwater management with tip how to integrate these into your development projects.  See Planning and Development Aids

• Site Design and Source Control GUIDELINES

CASQA New Development and Redevelopment Handbook

Start at the Source: Design Guidance Manual for Stormwater Quality Protection

Stormwater Management Manual for Western Washington: Volume IV -- Source Control BMPs

 
Step 3: Treat Remaining Runoff

Once development impacts have been minimized through site design measures, the remaining runoff must be treated and flows conveyed in a non-erosive manner. Staff from the County’s Public Works Department, Water Resources Division, will determine whether the submitted design plans meet these criteria for water quality and flood control.

Water Quality: All runoff from a design storm must be treated prior to discharge from the project site. The criteria for treating storm water runoff are described in the County of Santa Barbara Standard Conditions for Project Plan Approval - Water Quality BMPs (and Figure 1). For information on water quality conditions, contact Santa Barbara County Project Clean Water staff at 568-3561.

Examples of treatment control measures for residential development

Example treatment control measures for commercial development

Maintenance Agreement – Form used to document the site-specific maintenance agreement terms between property owner/subdivider and County

Engineer’s Certificate – Form filled out by responsible engineer upon successful installation of water quality facility as per plans.

Acceptable treatment control design guidance:

CASQA New Development and Redevelopment Handbook

Ventura County Storm Water Urban Impact Mitigation Plan (SQUIMP)

Los Angeles Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP)

San Diego Standard Urban Stormwater Mitigation Plan for Land Development and Public Improvement Projects (SUSMP)

Flood Control: The criteria for managing and preventing peak discharge rates are described in the Flood Control Standard Conditions of Project Plan Approval. See County-approved method for customizing the Curve Number used in hydrologic analysis, to take advantage of and get credit for low impact design. For information on flood control conditions, contact Santa Barbara County Flood Control District staff at 568-3440.  

 

Supporting Information

The following PowerPoint presentations provide a summary of the County’s requirements under the NPDES post-construction program:

Home Builders Association Central Coast Chapter

P&D Staff Training

Planning Commission

The following draft report was prepared by Wallace Group / Larry Walker & Associates. It evaluates the County’s development review process in terms of meeting the NPDES General Permit requirements and makes recommendations for improvement, with emphasis on addressing Low Impact Development. Appendix A lists the areas of authority and practice where Attachment 4(B) Design Standards are addressed by the County.

Report on Santa Barbara County's Development Review Process (Appendix A, Appendix B, Appendix C)

 

For more information on Post Construction, contact Cathleen Garnand at (805)568-3561.