Brantner Gulch and Tributaries Major Drainageway Plan and Flood Hazard Area Delineation

Project Background

This project includes a Major Drainageway Plan (MDP) and Flood Hazard Area Delineation (FHAD) for three main watersheds. Click on this link to view the project limits. The three watersheds are:

  • The 10.1-square mile Brantner Gulch Watershed, which includes the Lakeview, Plains, Quails Way, Horizon, Pheasants Run, and Fairgrounds Tributaries
  • The 0.97-square mile South Platte River (SPR) Southern Tributary 6 Watershed
  • The 1.1-square mile SPR Northern Tributary 7 Watershed

The project sponsors are the Urban Drainage and Flood Control District (UDFCD), City of Thornton, City of Northglenn, and Adams County. The sponsors hired Olsson to conduct the study.

The main objectives of this study are to update the hydrology, develop alternatives and a conceptual design to alleviate potential flooding and to address identified problems, and delineate flood hazard areas. The information from this study will provide a guide for project sponsors to use for floodplain management, future planning, and future construction projects within the three watersheds.

Key project tasks include the following:

  • Develop hydrology that reflects both the existing and the future land uses
  • Identify existing flooding, conveyance, and bridge and culvert overtopping issues
  • Develop drainage improvement alternatives
  • Hold a public open house to obtain input from the public on the project and findings
  • Develop a preliminary design of the alternative selected by the project sponsors
  • Delineate the floodplains along Brantner Gulch and its tributaries, SPR Southern Tributary 6, and SPR Northern Tributary 7

Project Sponsors

Urban Drainage and Flood Control District
City of Thornton
City of Northglenn
Adams County
Olsson | 1525 Raleigh Street, Suite 400, Denver, CO 80204 | (303) 237-2072