Drainage Area Management Plan (DAMP)

The specific water pollutant control elements of the Orange County Stormwater Program are documented in the 2003 Drainage Area Management Plan (DAMP) which is the Permittees’ primary policy, planning and implementation document for municipal NPDES Stormwater Permit compliance. The DAMP was prepared and is periodically updated using a consensus building process that involving public and private sector input and public review through the California Environmental Quality Act (CEQA) process.

The main objective of the DAMP is to fulfill the commitmen of the Permittees to develop and implement a program that satisfied NPDES permit requirements

The DAMP describes the agreements, structures and programs that:

  • Provide the framework for the program management activities and plan development DAMP Section 2.0 and Section 3.0);
  • Provide the legal authority for prohibiting unpermitted discharges into the storm drain system and for requiring BMPs in new development and significant redevelopment (DAMP Section 4.0);
  • Improve existing municipal pollution prevention and removal best management practices (BMPs) to further reduce the amount of pollutants entering the storm drain system (DAMP Section 5.0);
  • Educate the public about the issue of urban stormwater and non-stormwater pollution and obtain their support in implementing pollution prevention BMPs (DAMP Section 6.0);
  • Ensure that all new development and significant redevelopment incorporates appropriate Site Design, Source Control and Treatment Control BMPs to address specific water quality issues (DAMP Section 7.0);
  • Ensure that construction sites implement control practices that address control of construction related pollutants discharges including erosion and sediment control and on-site hazardous materials and waste management (DAMP Section 8.0);
  • Ensure that existing development will address discharges from industrial facilities, selected commercial businesses, residential development and common interest areas/homeowner associations (Note: The San Diego permit explicitly outlines a residential component, but the Santa Ana permit is more general about residential requirements)(DAMP Section 9.0); 
  • Detect and eliminate illegal discharges/illicit connections to the municipal storm drain system (DAMP Section 10.0);
  • Identify impacted receiving waters and produce environmental quality information to direct management activities, including prioritization of pollutants to support the development of specific controls to address these problems (DAMP Section 11.0); and
  • Assess watersheds and manage urban runoff on a watershed basis (DAMP Section 12.0).

The need to address increasingly prescriptive permit requirements and provide greater Permittee accountability, while maintaining the beneficial and synergistic cohesion of a countywide program, has been addressed through separation of the DAMP’s policy and planning areas. As a result of this separation, the 2003 DAMP now includes Local Implementation Plans (LIPs – also termed Jurisdictional Urban Runoff Management Programs – JURMP – in the San Diego Regional Board Third Term Permit). The LIPs were created to assist each Permittee in implementing an increasingly complex program within its jurisdiction while maintaining a single policy document that addresses two sets of permit requirements. The LIPs were completed by the San Diego Permittees in February 2003 and by the Santa Ana Permittees in June 2003.

The requirement to overlay separate, but nonetheless, highly interrelated water quality protection and planning processes based on hydrologic rather than political boundaries was addressed through the creation of Watershed Action Plans (WAP). A WAP (see DAMP Appendix D) was created for each of the six watersheds under the jurisdiction of the San Diego Regional Board in August 2003. A model WAP was created for the Newport Bay watershed during 2005-06 and draft WAPs are being prepared for the other watersheds in the area of Orange County under the jurisdiction of the Santa Ana Regional Board.