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Soils for Salmon – Construction Best Practices

Builders, developers, and landscapers are adopting practices that preserve and improve the soil on building sites to protect our waterways. Local governments including Seattle now require it.

Advantages to builders, consumers, and the environment include: more marketable buildings with healthier landscapes, better erosion control, easier planting, easier long-term maintenance with less water and chemical needs, and reduced stormwater runoff with better water quality for salmon, wildlife, and people too.

Soil best practices during construction:

  1. Retain and protect native topsoil & vegetation where practical.
  2. Restore disturbed soils to healthy soil function by: stockpiling & reusing good quality site soil; or tilling 2-3" of compost into site soils; or bringing in 8" of compost- amended topsoil. Loosen compacted subsoil, if needed, by ripping to 12" depth.
  3. Mulch landscape beds after planting. Protect restored soils from erosion or re-compaction by heavy equipment.

Related links

Green Stormwater Infrastructure – Seattle’s Low Impact Development stormwater requirements, that start with the soil.

Links to other sites

Learn more about soil, stormwater, and local soil restoration requirements:

Soils for Salmon – background science, design guidelines, compost calculator, images, videos, and soil and stormwater information.
Building Soil – guidelines for builders, landscapers, and developers, with links to State and local code requirements and construction erosion control with compost. Seattle’s
Post-Construction Soil Management Requirements (pdf) on Department of Planning and Development site.
Soils for Salmon Report (pdf) Integrating Stormwater, Water Supply, and Solid Waste Issues in New Development and Existing Landscapes – an illustrated report on the regional Soils for Salmon initiative.
BioCycle Journal articles: Soils for Salmon Update (2007) and Green Infrastructure (2011).