As a part of a larger utility and roadway improvement project, Valerian assisted the City of Greeley and ICON Engineering with the design of seven water quality infiltration basins located at the intersection of 7th Ave and 14th and 15th Streets. During the design process Valerian worked to vet numerous water quality alternatives including bump out infiltration basins, linear ‘green gutters’, vegetated bio-swales, and permeable pavers. Following discussions with the design team and Greeley personnel it was determined that a series of bump out infiltration basins located at two intersections would provide the greatest volume of water quality capture as well as the lowest chance of conflicts with existing and proposed utilities.
Each bump out consists of a curb cut leading to a forebay with a slotted forebay wall, to promote the deposition of sediment, followed by a series of sunken basins with growing media designed for infiltration as well as vegetation establishment. The basins are planted with a combination of seed and plugs using hardy grasses and perennials that were selected for resiliency in roadside conditions.
Each corner posed unique challenges that needed to be addressed, as a result no two corners are exactly the same. The water quality bumpouts were individually designed to provide as large of a forebay as possible to allow for ease of maintenance.