Environmental benefits of wastewater treatment upgrades
The City of Winnipeg has put in place a plan to upgrade wastewater treatment to improve effluent disinfection and reduce nutrients to meet the levels specified in the Environment Act licences. The licences set our treatment levels to protect public health and the freshwater environments of the local rivers and Lake Winnipeg.
- To protect public health, limits in wastewater effluent for pathogens such as fecal coliform and E. coli. have been set. Reducing pathogens lowers the risk of contracting gastrointestinal illness by people that use the local rivers for recreational purposes.
- To protect aquatic life from the potentially harmful effects of un-ionized ammonia, effluent ammonia limits have been set for ammonia concentration, water temperature, and pH based on the Manitoba Surface Water Quality Standards Objectives and Guidelines.
- To protect water habitats from the effects of nutrient enrichment, nitrogen and phosphorus limits for effluent have been set. Excessive nutrient enrichment causes water quality deterioration and potentially large algae blooms.
Benefits of water pollution control centre upgrades:
The City of Winnipeg currently contributes 4.2% of the total nitrogen load and 6.6% of the total phosphorus load to Lake Winnipeg. As the tables below show, after the overall City nutrient-reduction program reduction is complete:
- nitrogen loads will be lowered by 1,708 tonnes per year or about 2.2% and
- phosphorus loads will be lowered by 292 tonnes per year or about 2.4%
Detailed information on the benefits of upgrades for each of our three treatment plants is also available:
- West End Water Pollution Control Centre (WEWPCC)
- South End Water Pollution Control Centre (SEWPCC)
- North End Water Pollution Control Centre (NEWPCC)
Summary of projected City of Winnipeg annual load reductions to Lake Winnipeg resulting from nutrient removal
| Nitrogen | Phosphorus | ||||||
| City reductions | Target date | Tonnes | % of City load | % of total load | Tonnes | % of City load | % of total load |
| Provincial interim objectives | 2007 | 460 | 13 | 0.5 | 46 | 10 | 0.7 |
| CSIF project reduction | 2012 | 673 | 19 | 0.8 | 105.5 | 23 | 1.5 |
| Overall City program reduction | 2014 | 1708 | 47 | 2.0 | 292.5 | 65 | 4.3 |
Current and projected annual Lake Winnipeg load contributions
| Source1 | Nitrogen | Phosphorus | ||
| Tonnes | % of total | Tonnes | % of total | |
| Upstream of Manitoba | ||||
| - United States (Red and Souris rivers) | 20,100 | 21.0 | 2,700 | 34.0 |
| - Saskatchewan and Alberta (Saskatchewan and Assiniboine rivers) | 8,300 | 8.7 | 400 | 5.0 |
| - Ontario (East side and Winnipeg River) | 20,500 | 21.4 | 1,100 | 13.8 |
| Manitoba sources | ||||
| - Point sources outside of Winnipeg | 1,400 | 1.5 | 300 | 3.8 |
| - Estimated natural background | 18,100 | 18.9 | 1,300 | 16.4 |
| - Agriculture | 5,100 | 5.3 | 1,200 | 15.1 |
| - Atmospheric load | 27,400 | 28.6 | 500 | 6.3 |
| Subtotal without City of Winnipeg | 92,300 | 96.2 | 7,500 | 94.3 |
| City of Winnipeg2 | 3,618 | 3.8 | 450 | 5.7 |
| Current totals | 95,918 | 100.0 | 7,950 | 100.0 |
| Projected after overall City program reduction | ||||
| Subtotal without City of Winnipeg | 83,054 | 97.8 | 6,402 | 97.6 |
| City of Winnipeg after reductions3 | 1,910 | 2.2 | 158 | 2.4 |
| Projected totals | 84,964 | 100.0 | 6,560 | 100.0 |
1 Lake Winnipeg loads from Manitoba Water Stewardship Lake Winnipeg Stewardship Report - Decemeber 2006
2 Updated data based on detailled monitoring done by the City of Winnipeg
3 Includes urban wet weather sources.
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This page was last updated on October 2, 2008 |
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