The Cohen’s Drainage watershed drains approximately 3.6 square miles of both developed residential areas and designated open space within Douglas County. Bisected by Daniels Park Road, the drainage basin drains from the northern slopes, south to its confluence with East Plum Creek downstream of Highway 85. The project team will determine peak flow rates for the current, fully developed conditions as well as the historic, pre-development watershed conditions. The development of detailed hydraulic models allows for a comprehensive evaluation of potential erosion and flooding issues. Updated and refined floodplain mapping will replace the legacy Zone A FEMA floodplain maps where they exist.
While the watershed has very few known issues, the team will be evaluating publicly owned or maintained infrastructure to determine flood control adequacy, evaluate the facility’s overall functionality, and recommend improvements as needed. The watershed’s ecology and geologic characteristics will be considered in the assessment of current and potential erosion trends that may merit stabilization against future sedimentation or degradation issues. These evaluations and any potential recommendations will assist MHFD and the County with the long-range planning and implementation of future improvements that serve to protect people, property, and the environment.
Project Manager Contact Information:
Brad Robenstein, P.E., CFM
Douglas County Project Manager
Douglas County Department of Public Works and Engineering
100 Third Street
Castle Rock, CO 80104
Phone: (303) 660-7490
|Jon Villines||MHFD||Project Manager|
|Shea Thomas||MHFD||Watershed Services Manager|
|Brik Zivkovich||MHFD||Staff Engineer|
|Brad Robenstein||Douglas County||Sponsor|
|Craig Hoover||Bohannan Huston, Inc.||Principal-in-Charge|
|Jared Lee||Bohannan Huston, Inc.||Project Manager|
|Rifka Wine||Bohannan Huston, Inc.||Project Engineer|
|Madeline Olivas||Bohannan Huston, Inc.||Project Engineer|
- Determine updated fully-developed and pre-development hydrologic conditions
- Map major waterway flood hazards to MHFD’s current Flood Hazard Area Delineation (FHAD) standards.
- Identify areas of concern related to watershed ecology and either current or future erosion potential.
- Preserve natural channel character and habitat, while improving waterway function
- Identify master planned improvements, where merited, and incorporate into Major Drainageway Plan (MDP).
|Deliverable||Draft Submittal||Final Submittal||Public Meeting||Status|
|Baseline Hydrology||N/A||December 2019||N/A||Completed|
|FHAD||December 2020||January 2021||N/A||On-going|
|Alternatives Analysis Draft||March 2021||May 2021||April 2021|
|Conceptual Design Draft||July 2021||September 2021||N/A|