RESPEC PROJECT

The Second Creek area faced recurring flood hazards that required a comprehensive approach to mitigate risks and streamline flood management. The Denver International Airport, Mile High Flood District, Adams County, Brighton City, and Commerce City needed a plan to manage the drainage and flood hazards, reduce downstream peak flows, conduct complex floodplain modeling, and ensure compliance with Federal Emergency Management Agency (FEMA) regulations for floodplain revision.

RESPEC collaborated with these stakeholders to develop a Major Drainageway Plan (MDP) and Flood Hazard Area Delineation (FHAD) for Second Creek. Our team executed a robust approach involving a detailed hydraulic and hydrologic (H&H) modeling plan, floodplain delineation, and master planning for the Second Creek watershed. Leveraging advanced one-dimensional (1D) HEC-RAS modeling, informed by a 2D HEC-RAS model, we could accurately predict flow patterns, even in complex scenarios.

Integral to the project’s success was close coordination with large developers and landowners, leading to the formulation of a phased detention scheme. This scheme reduced flooding downstream and offered a practical framework for the development community to implement in stages.

The project’s impact was two-fold. First, it created a safer environment for stakeholders, enhancing their resilience against floods. Second, the plan’s successful execution contributed to advancing floodplain management practices in the Second Creek area. By employing advanced modeling techniques and collaborating closely with developers and landowners, RESPEC mitigated flood risks and implemented effective solutions. Our comprehensive H&H modeling plan and floodplain analysis provided invaluable information to FEMA, significantly enhancing the Physical Map Revision process for Second Creek.