New Development Stormwater Requirements
Stormwater Quality Requirements for Development Projects
Water Quality regulations for Priority Projects include Low Impact Design (LID) on-site retention requirements and Hydromodification Management measures which can be significant elements in the site design of your project and therefore it is crucial that they are considered early in the design process.
All development/redevelopment projects, regardless of priority, shall implement the site design and source control principles, where applicable and feasible, to maximize infiltration, provide retention, slow runoff, and reduce pollutants at the sources.
All priority projects shall meet the Water Quality Management Plan (WQMP) and Hydromodification Management Plan (HMP) requirements as described in the documents and tools below. The project's WQMP is a plan for minimizing the adverse effects of urbanization on site hydrology, runoff flow rates and pollutant loads. Hydromodification management measures address the changes in the magnitude and frequency of stream flows and associated sediment load due to urbanization or other changes in the watershed land use and hydrology and the resulting impacts on receiving channels, such as erosion, sedimentation and potential degradation of in-stream habitat.
To determine if your project is a priority project, use the WQMP Checklist Priority Development Project (PDP) Criteria.
Note: The Preliminary WQMP (pWQMP) is required as part of the Project Application. An application will not be deemed complete without a WQMP. It should be noted that the WQMP is not a "conceptual" document in the normal sense of the word and requires detailed engineering sizing calculations and location details for selected BMPs.
The following updated documents and tools will assist you in preparing an acceptable Water Quality Management Plan for your project.