Regional Water Quality Control Board Order R9-2007-0001 Provision D.1.g (6) (Board Order) requires the County of San Diego and its NPDES Co-permittees to develop a Hydromodification Plan to manage the increases in runoff discharge rates and durations from all Priority Devlopment Projects, where such increased rates and duratons are likely to cause erosion of channel beds and banks, sediment pollutant generation, or other impacts to benefical uses and stream habitat due to increased erosive force.
A key element of the creation of the San Diego HMP is the involvement of a Technical Advisory Committee (TAC). The TAC members consist of respected individuals from academia, technical resource agencies, the development community, consulting engineers, and environmental organizations. The TAC was tasked with providing technical input to the scientific approach and interpretation of results integral to the establishment of numerical flow control standards for the HMP.
The HMP can be found as an appendix to the Model SUSMP. Any priority development project subject to SUSMP requirements is also subject to HMP requirements.
Hydromodification Plan (Final, March 25, 2011)
Rain Gauge and Rainfall Data Selection – technical memo