Lone Tree Creek Stream Restoration

Project Abstract

Lone Tree Creek, a stormwater drainageway located in the southeast Denver metro area, runs through Centennial Center Park on its way to Cherry Creek. Centennial Center Park, an award-winning facility, is a flagship destination for the families and residents of the City of Centennial. The stream is in a generally disconnected and underutilized area of the park along the western boundary. Additionally, the stream and the two culverts that bound our study area are undersized and incapable of safely conveying the runoff from a 100-year storm event without flooding adjacent roadways. The stream has been subject to past improvements which have since fallen out of favor with modern best practice, including a concrete drop structure and concrete-lined low flow channel.

We propose to restore this reach of Lone Tree Creek to a more natural channel design by constructing a composite channel with a meandering gravel and cobble lined streambed, along with native grass floodplains that give the stream the space to safely flood during a large storm event. The concrete drop structure is to be eliminated and the grade of the stream controlled by three reinforced riffle sections. Both culverts are to be upsized to be capable of conveying the flows from a 100-year storm event, and the upstream culvert should include a pedestrian underpass to connect to a regional trail system south of the study area. Existing outfalls are to be modified to meet the new channel alignment, and Flexamat rundowns are proposed to increase stability and water quality. A new crosswalk across neighboring Peakview Avenue, guardrails over the Peakview culvert, and a new pedestrian bridge across the stream will connect the stream area to the surrounding recreational facilities and increase public usage and safety. Gravel footpaths will lead parkgoers to boulder and sandstone sitting areas along slower moving parts of the stream to allow for safe interaction with the water. An interpretive playground should be constructed with Nature Play equipment and an educational theme around native flora and riparian ecosystems, along with a permanent monument of land acknowledgement for the Indigenous communities who were the original inhabitants of this land. These communities should also be engaged as partners in developing the aesthetic and educational features of the new park amenities.

Project presentation

Project poster