Alternative Methods of Sanitary Servicing for the City of Airdrie

The City of Airdrie studied the feasibility of alternate wastewater processing methods in order to identify the best wastewater servicing scheme for new residential, commercial, industrial and institutional development. The city’s preliminary preference was a solar aquatics system for wastewater treatment, in combination with a water reuse system (involving storage and pumping) for irrigation of public and private lands and for other non-potable uses such as toilet flushing in commercial, industrial or institutional buildings. The study evaluated this preferred alternative as well as other servicing options, taking into consideration capital costs, operating and maintenance costs, life-cycle costs and the method’s footprint. The study also identified anticipated reductions in water and energy consumption and associated cost savings. These figures were compared to the city’s process of treating its wastewater in Calgary. The key criteria for selecting and confirming the preferred wastewater servicing scheme were to include regulatory requirements and life-cycle costs and benefits (economic and environmental). If the city selected an alternate form of wastewater servicing that included water reuse, the new system would reduce water consumption, reduce the amount of water pumped to Calgary for treatment and save energy and costs. Unlike conventional wastewater treatment systems, a solar aquatics system was not expected to require the use of chemicals and would compost the sludge generated in water treatment.