(Tacoma, WA) Starting in 2000, the Tacoma Housing Authority undertook the largest residential redevelopment in the history of the City of Tacoma--Salishan, a residential complex consisting of 855 old, worn out, and unsightly public housing units built during World War II to house war workers and their families. The Salishan Redevelopment project was funded by a Federal HOPE VI Grant. The redevelopment required refurbishment of housing units and replacement of site infrastructure, including the electrical grid, water distribution system, sewers, stormwater system, roads, curbs, and lights. Landau Associates provided geotechnical engineering services to support the redevelopment of about 161 acres of developable land within a 200 acre site. The geotechnical information was also used to assess soil and foundation impacts in the geological section of the NEPA document prepared by Tacoma Housing.
One of the project goals for the Salishan redevelopment was the use of low-impact storm drainage systems to reduce the amount of impervious area and infiltrate as much stormwater as possible onsite. Landau Associates completed geotechnical investigation to identify areas where stormwater infiltration was feasible and provided recommended design infiltration rates. In addition, Landau Associates evaluated potential impacts to critical areas and provided geotechnical recommendations for design and construction of the project. Geotechnical recommendations were developed for site grading, foundation support of structures, seismic design criteria, installation of new underground utilities, and pavement design. Landau Associates also provided construction support services.