West Vine Drainage Basin Stormwater Master Planning#
Basin Master Plan History#
The original stormwater master plan for the West Vine Basin was completed in 1980 and updated in 1998. Consistent with other major drainage basins within the City of Fort Collins, a comprehensive update to the 1998 study was completed in 2002.
This update was completed in the aftermath of the 1997 flood and associated update to the City’s rainfall criteria. The focus of the 2002 master plan study was to provide a basis for stormwater management while taking into consideration drainageway management, reduction of hazards due to flooding, reduction of property damage, effective use of public funds, property value enhancement, and a cost/benefit analysis of improvement alternatives including water quality, channel patterns and ecology.
In 2012, the City completed an update to a portion of the Basin Stormwater Master Plan to address water quality considerations and to identify and prioritize stream rehabilitation and stability projects that protect the City’s urban watersheds and preserve natural and beneficial functions of floodplains. This effort included completion of an Urban Stream Health Assessment, identification of basin-specific best management practices (BMP’s) to address water-quality, and completion of a stream rehabilitation project prioritization. Over $1.3 million of water quality improvements were recommended within the West Vine Basin.
Master Plan Updates#
The current effective floodplain mapping for the West Vine Basin was developed more than 18 years ago in conjunction with adoption of the West Vine Basin Stormwater Master Plan in 2002.
Since then, significant advances in technology have resulted in the availability of more accurate topographic data, as well as an increase in the capabilities of hydrologic and hydraulic modeling software. Using these new technologies and data, the City Stormwater staff can now more accurately identify potential areas subject to flooding.
Updated floodplain mapping is needed to better understand and identify the current flood risk based on present-day development within the basin. The following provides an overview of the current Basin Master Plan updates:
2015-2016 HYDROLOGY UPDATE
Fort Collins Utilities, in partnership with Larimer County, began a study to update the hydrologic model for the West Vine Basin as part of an update to the overall Stormwater Master Plan.
2017-2020 HYDRAULICS AND FLOODPLAIN MAPPING UPDATE
Based on results from the updated hydrologic analysis, an update to the hydraulic model for the basin was completed. As part of the hydraulics update, new floodplain and floodway boundaries were developed using detailed topographic data and the latest hydraulic modeling software. These boundaries are the most accurate and up-to-date representation of flood risk in the basin.
2020-2021 SELECTED PLAN UPDATE
With the update to the hydrologicand hydraulic modeling and associated floodplain mapping, Fort Collins Utilities and Larimer County are currently initiating an update to the Selected Plan of Improvements section of the Stormwater Master Plan.
The Selected Plan evaluates alternatives directed at addressing flooding issues identified in the floodplain update and then identifies a recommended plan of improvements. In addition to developing solutions to reduce flood risk, the Selected Plan evaluates opportunities for water quality improvements, stream rehabilitation, habitat enhancement, open space preservation and recreation (e.g., parks, trail systems).
At the conclusion of the Selected Plan update, a list of the improvements will be created and incorporated into Fort Collins’ citywide Capital Improvement Project (CIP) prioritization process. Projects identified in Larimer County will be entered into the County’s CIP prioritization process. Both the updated Master Plan and new floodplain mapping will be adopted in 2021 after an in-depth public outreach effort.