Lowell Blvd. over Nissen Tributary – City and County of Broomfield, Colorado

Muller prepared preliminary and final design plans and bid documents for widening the Lowell Boulevard corridor from West 120th Avenue to Midway Boulevard from a two-lane roadway to a four-lane roadway with left turn lanes, bike lanes, sidewalks, and striped and raised medians. For this project, Muller designed a major structure over the Nissen Reservoir channel, a multi-purpose trail, and a retaining wall for the trail tunnel under the bridge. This trail is part of the City and County of Broomfield’s extensive network of trails that provide opportunities for residents and visitors to enjoy connected open space, parks, and trails.

The original crossing consisted of several small culverts and was substantially undersized and subject to frequent flooding. The new structure is a twin-cell precast arch on deep foundations (steel piling). Associated structures include a trail underpass floodwall, low-flow pedestrian crossing, and extension of the Brandywine Tributary concrete box culvert. Custom wall formliners, concrete stains, and wildlife stencils emphasize the connection to the adjacent Metzger Farm open space.