East Toll Gate Creek & Toll Gate Creek (Lower) MDP & FHAD
The joint Urban Drainage and Flood Control District, City of Aurora, Arapahoe County, and Southeast Metro Stormwater Authority East Toll Gate Creek project, was a multi-phased analysis of the tributary and associated spurs from the creek’s headwaters to its confluence with West Toll Gate Creek. The phased analysis developed detailed project hydrology, delineated the creeks floodplain, and generated a Master Drainage Plan (MDP) and Flood Hazard Area Delineation (FHAD) study to manage stormwater runoff from the existing and future developments within the varied watershed. This evaluation was layered to calibrate field measurements and historic observations with previous studies to generate a useful and trustworthy document capable of quantifying regional requirements and impacts. Complex split flow conditions and varying project characteristics of this large tributary area generated a purposeful model designed to the unique conditions encountered within the watershed. One of the first studies to implement the excess urban runoff volume methodology on a regional scale, the project successfully met the stakeholder goals and a resulted in an adopted FHAD.