Biosolids Disposal measures the tonnes of biosolids generated and beneficially disposed through soil improvement and composting. Biosolids are the nutrient-rich organic by-product of domestic wastewater treatment that contains essential plant nutrients and organic matter. When biosolids disposed is greater than the amount of biosolids generated each month, stored biosolids can be removed from the Clover Bar lagoons, which helps to minimize odours and potential impacts on the environment.
This measure reflects the City's commitment to reducing its impact on water, land, and air through continuous improvement toward zero pollutants and contaminants. This demonstrates the efforts of the City to protect the health of our people and our ecosystem and ensure the landscape in which we live can be safely enjoyed by all members of our community. It is also reflective of the efforts to improve odour control by increasing the tonnes of biosolids that are beneficially disposed each year and begin reducing biosolids stored in lagoons.
Explanation of Performance
In accordance with the Biosolids Long Term Strategy, the City is commited to reducing the biosolids inventory present in the Clover Bar lagoons. Reducing the biosolids inventory is critical to manage the risks the lagoons pose to the City, the environment and the public. By tagetting a beneficial reuse of 36,000 dry tonnes of biosolids generation the City and its partners have a plan in place to reduce 100,000 dry tonnes of the inventory in the lagoons over the next 15 years. The largest risk to the biosolids beneficial reuse program is the weather. A rainy summer would limit the land application program and cause the City to fall short of this target. The City has moved to diversify the available beneficial reuse options to mitigate a portion of the weather related risk. The beneficial reuse target of 36,000 dry tonnes is based on an expected biosolids production of 30,000 dry tonnes and a 6,000 dry tonne inventory reduction. If generation is lower than expected, than the City will be able to meet it's inventory reduction targets sooner.
Did You Know?
The City of Edmonton is partnered with both EPCOR and the Alberta Capital Region Wastewater Commission to manage the region's biosolids. Approximately half of the beneficially reused biosolids are used to generate compost at the Edmonton Waste Management Centre of Excellence. Most of the remainder is agriculturally land applied in the region. Biosolids contains nitrogen, phosphorous and important organic material which provides benefit to agricultural producers. Recently the City has begun non-agricultural land application, primarily for mine reclamation and marginal land improvement.
Biosolids Management: http://www.edmonton.ca/city_government/utilities/biosolids-management.aspx
Residential Sewer System: http://www.edmonton.ca/residential_neighbourhoods/drains_plumbing_sewers/drainage-sewer-system.aspx
Sewer Facts: http://www.edmonton.ca/city_government/utilities/sewer-facts-and-statistics.aspx