Soil Improvement & Land Reclamation

Benefits of biosolids

Biosolids are filled with nutrients and organic matter, the very thing that unhealthy soils need. The organic matter helps build the soil’s structure, which helps it hold water (or drain water), reduces erosion, and provides an ideal environment for plants. Soil microorganisms get really happy, and go to town breaking down the organic matter and releasing nutrients for the plants. All of this happens at warp speed, and soon degraded urban and suburban soils are healthy again. Healthy soils means healthy plants and a healthier, green environment for the people that live in these urban and suburban areas.

How it Works 

Soil improvement and land reclamation projects use onetime or infrequent applications of large quantities of biosolids to increase the amount of nutrients and organic matter in poor or damaged soils. The nutrients in the biosolids jump-start the growth of plants on the site and provide a reserve of nutrients that plants can access over time. Following biosolids application, soil is better aerated and lighter. Water enters into the soil rather than eroding off the soil surface. Unlike nutrients in commercial fertilizers, nutrients added in the biosolids will stay in the topsoil over time and the restored ecosystem will continue to prosper over time.

What’s happening

Here are some of the ways biosolids have reclaimed damaged soils:

Wildlife habitat enhancement – Invasive plants like Scotch broom and blackberry vines can take over natural wildlife habitats. To re-establish native grasses and plants, biosolids have been tilled into the soil and reseeded with grasses and other native plant species following the removal of invasive plants.  These improvement projects remain welcoming wildlife habitats for years to come.

Copper mine reclamation – Biosolids help reclaim soils impacted by mining activities.  As a part of restoring former mines, biosolids helps to revegetate extensive areas of piled rock and mine tailings and stabilize slopes. Researchers have also studied which tree species are the best fit for screening trials and plant establishment in reclaimed mine tailings. 

Wetlands restoration – Biosolids, biosolids compost and yard debris compost have been used to restore land to previous wetland characteristics. The nutrient-rich organic material provided an excellent growth medium for native wetland plant species, while stabilizing slopes. This successful venture may lead the way for other wetland restoration projects in urban environments.

Shoreline reclamation – Biosolids is being used in shoreline stabilization and the establishment of wildlife habitat protecting sensitive west coast fish populations.

Road reclamation: The Mountains to Sound Greenway Trust, centered in King County, Washington, has applied Class A biosolids compost to revegetate logging road scars and landings in the foothills of the Cascade Mountains along the Interstate 90 corridor. The Mountains to Sound Greenway Trust is a public-private partnership dedicated to maintaining a green belt for approximately 100 miles along Interstate 90 from Ellensburg to Seattle.

Rangeland restoration – Biosolids applied to rangeland has significantly improved rangeland vegetation and soil fertility.  In turn, farmers have seen enhanced forage quality and higher beef yields.  Windblown dust is also reduced on the biosolids amended soils and water-holding capacity is increased.

Gravel pit reclamation – Former sand and gravel mines have utilized biosolids to establish vegetation.  One former gravel pit was transformed into a U.S. Open Championship Golf Course.