Tres Rios Environmental Restoration

Logan Simpson was part of a multidisciplinary design build team responsible for the environmental restoration and rehabilitation for an approximately 1.5-mile reach of the Salt/Gila River between 107th and 119th Avenues  for the US Army Corps of Engineers, as sponsored by the City of Phoenix. The long-term goal was to restore native Sonoran Desert aquatic and riparian habitats along this Salt/Gila River reach. Multiple iterations of hydraulically-modeled, site-sensitive riverbed recontouring (grading) plans were prepared and evaluated for hydraulic efficiency and cost effectiveness.  The plans were developed with the intent to preserve important existing Cottonwood/Gooddings willow groupings that had been inventoried by Logan Simpson and known threatened and endangered species (Yellow-billed Cuckoo and Southwestern willow flycatcher) habitats, to replicate as closely as possible historic braided stream patterns and cross sections, to seamlessly accommodate storm drainage inflow sources into the overall restoration plan, and to create  sustainable, stratified native aquatic and riparian habitats. The project included the restoration of riparian and wetland marsh habitats, open water, and other upper terrace floodplain habitats along the River reach and the removal of exotic, invasive and/or noxious plants (predominantly Salt Cedar). Logan Simpson led the watercourse layout and alignment study, was the lead restoration designer, developed the restoration chapter of the Design Analysis Report, and prepared native plant inventories, landscape and wetland restoration plans, a SWPPP, a spill prevention control plan, and O&M guidance to assure long term success of the project.

In addition, Logan Simpson was the primary designer for five trailheads that provide gateways to multiuse trails. We coordinated environmental artwork (betterments) that were integrated at various vantage points. Logan Simpson worked closely with the design builder and general contractor, engineers, specialty contractors, USACE, and the City of Phoenix to develop a project that met flood control, habitat and ecosystem restoration, effluent conveyance, and water reuse goals. The project has won numerous awards, including an Award of Excellence from the American Society of Landscape Architects (Arizona Chapter); APWA Public Works Project of the Year; an Honor Award from Missouri Chapter of the American Council of Engineering Companies; a Merit Award AND Design Excellence Award from the Design Build Institute of America; an Arzona Forward Crescordia Award; and a Build Arizona Award from the Association of General Contractors (Arizona Chapter).