• New Development Information

  • New Development/C.3 Requirements

    Developers should check with the Town’s Planning or Engineering staff to determine if a project is subject to the new C.3. requirements.  If it is, they should obtain and review the Stormwater C.3 Guidebook before designing and submitting a construction project to the Town.  All applications that are subject to C.3., must include a Stormwater Control Plan (SCP) for the project with their application.  Guidance for completing a SCP is outlined in the Stormwater C.3 Guidebook.  C.3. project designs must plan for and incorporate the following design features into the project prior to determining the site plan layout:
    • Minimize the area of new impervious areas such as, roofs and paving;
    • Use pervious surfaces instead of paving, where feasible, so that runoff can percolate to the underlying soil;
    • Plan to capture and treat runoff from all impervious areas; and
    • Determine the required size and number of treatment areas and devices using the C.3. Guidebook and make room for these drainage features in the site plan; and  
    • Projects over one acre of impervious area may also be subject to additional Hydromodification requirements.

    The new “C.3” provisions are separate from—and in addition to—requirements for erosion and sediment control and pollution prevention measures during the construction phase of the project.  In addition, project applicants must prepare plans and execute operations and maintenance agreements to insure that the stormwater treatment devices are maintained in perpetuity.

    Through the Contra Costa Clean Water Program, local governments have created a Stormwater C.3 Guidebook available here to help developers comply with the new C.3. requirements.  Please visit the Contra Costa Clean Water Program website for a more detailed and thorough explanation of all Stormwater regulations: http://www.cccleanwater.org/c3.html

    The information contained on this website will help you successfully plan for “C.3” compliance for your project.