Creek Restoration Walks: Flood Projects Will Lead to Bike/Ped Connections on Westerly Creek

By Brian Hyde

As recently as 1979, there was not a continuous channel for Westerly Creek from Richthofen Place to 17th Avenue. Floodwaters had to find their way along streets and alleys and around buildings, as well as through them. Yosemite Street served as the channel at the intersection of East Colfax Avenue and Yosemite.

After WWII, the Denver area, including the Westerly Creek watershed, grew rapidly. Along all of the streets between Lowry Air Force Base and Stapleton Airport residential buildings (single-family and multi-family) and non-residential buildings were constructed with no provisions for Westerly Creek. Mother Nature offered plenty of warnings: a 40-year flood and a 60-year flood in 1945, a 20-year flood in 1950, a 50-year flood in 1951 and a 65-year flood in 1973. The combination of incomplete or non-existent floodplain mapping, minimal or non-existent floodplain regulations, and the exacerbation of flood risk though upstream urbanization had led to numerous decisions in the 40s, 50s and 60s that made flood damage more likely.

In 1953, the Air Force constructed Kelly Road Dam to reduce flood flows downstream of Lowry. Nothing further was done for about 25 years. In 1977 the Urban Drainage and Flood Control District (UDFCD) delineated the 100-year floodplain for Westerly Creek from the north end of Lowry (11th Avenue) to the confluence with Sand Creek at Stapleton Airport. Flood depths ranged from approximately one foot to nine feet. By 1980, UDFCD had constructed a flood control project consisting of open channel sections alternating with underground storm sewer sections from Lowry to Stapleton. The floodplain was reduced, but from approximately 12th Avenue to Montview Boulevard, the flood hazard was still substantial.

In 1989 the Air Force constructed Westerly Creek Dam in the southeast quadrant of Lowry, further reducing the outflow from Kelly Road Dam. Even so, there are still flood problems north of 13th Avenue, particularly from Colfax to Montview. Meanwhile, the closing of the air base and the airport and their subsequent redevelopment led to the creation of a vision of a continuous Westerly Creek greenway, including not just Lowry and Stapleton, but also the community between them. Eliminating flood hazards at Lowry and Stapleton has been accomplished by explicitly making floodplain and the greenway corridor one and the same. Between Lowry and Stapleton, things are far more complicated.

A brief bullet summary of flood protection gaps from Lowry to Stapleton that are also bike-ped gaps shows how the two objectives are linked, particularly in those locations where creek daylighting is possible:

Flood Protection/Bike-Ped Gaps in Denver:
1) New Freedom Park (13th & Xenia) to southwest corner of 14th and Yosemite (creek currently in undersized pipe – consider daylighting of creek);
2) 14th and Yosemite to southwest corner of Colfax and Yosemite (creek currently in undersized pipe – consider partial daylighting of creek);

Flood Protection/Bike-Ped Gaps in Aurora:
1) open space at 16th Avenue and Akron Street to Montview Park at 17th Avenue and Beeler Street (creek currently in undersized pipe – consider daylighting of creek);
2) Montview Park to Stapleton (Aurora is currently waiting for completion of environmental review of their grant application to FEMA for replacement of existing culvert crossing of Montview with a bridge.)

An expert in floodplain management, Brian Hyde leads a regular Creek Restoration Walk. For more information, email him at westerly_connect_brian@comcast.net or call 720-939-6039.