Stormwater bio-infiltration swale projects by Spokane County and WSU Spokane Extension
Lines were sprayed for Roundup application on the side slopes of the alternative swales.
Spokane Pro Care killed the grass with Roundup, and A.M. Landshaper stripped the sod.
On ditch-type swales, just a two-foot-wide trench was excavated.
Spokane County Stormwater Utility performed infiltration tests on the subbase soils.
Engineered soil mix was placed a foot deep and graded to specs…
and then either sodded…
or planted with alternative plants.
After the larger plants were in, the rock mulch and cobbles were placed.
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Then small plants and ground covers were planted through the rock mulch (and Karen Swanson helped).
Signs were put in the alternative swales to direct questions to Spokane County’s website.
The alternative swales: 906/912 E. Chatham Court, before and after reconstruction.
The plant palette for Chatham Court: potentilla, sedges, switchgrass, asters, columbines, and coneflowers.
1116/1124 E. Chantel, before and after.
Plants for Chantel: river birch, arborvitae, sweetspire. grasses, and white-flowering perennials and groundcovers.
12321 N. Denver Road, before and after.
Plants for Denver: aspens, false asters, coneflowers, tufted hairgrass, bee balm, cranesbill, and ground covers.
17602/17606 E. Ridge Court, the largest swale in the project, before and after.
Plants for Ridge Court: coneflowers, red and yellowtwig dogwood, switchgrass, Joe-Pye weed, ninebark, Arctic willow.
