At Grant Ranch, this Extended Detention Basin (EDB) is the first step in a treatment train approach used to treat stormwater from this residential development before entering Bow Mar Lake. MHFD has been monitoring the inflow and effluent from this EDB since 2002. Modifications to the entrance and outlet, completed in 2004, brought the design to conformance with MHFD criteria. Before and after photos speak to the value of including a micropool and initial surcharge volume in the design. This EDB serves as a good example for one of the most common BMPs in the Denver metropolitan area.
MHFD has posted a report summarizing the full history (2001-2011) of water quality and runoff reduction data associated with this site. MHFD submits all water quality data to the International Stormwater BMP database.
Grant Ranch EDB prior to construction of a micropool and energy dissipation.
Current photo of Grant Ranch EDB
Mucking out the micropool