Halifax, Nova Scotia
The Halifax Regional City (HRM) has had very limited wastewater treatment until just recently. In an effort to improve water quality in Halifax harbour, a $330 million project was started several years ago to:
- Provide a collection sewer system,
- Build 3 new wastewater treatment plants to serve Halifax City, Dartmouth and Herring Cove, and,
- Build a biosolids processing facility (BPF).
An existing wastewater treatment plant at the Halifax Aerotech Industrial Park services the airport, septage haulers and biosolids from several small wastewater treatment plants. When the entire project is completed the Halifax Region will own all of the facilities including the biosolids processing facility. The N-Viro processing facility has been operational since May 2007.
The biosolids processing facility (BPF) is located in the industrial park near the airport (Aerotech Park). Biosolids from the three new wastewater treatment plants and the existing Aerotech plant will be trucked to the BPF. The BPF will serve a population of approximately 400,000.
Hatch Engineering, under a design-build contract, built the BPF for HRM. N-Viro has an operating contract for complete operations of the BPF plus approvals, marketing and distribution of the product. This is a 5 year contract with 5 year renewals.
The three new wastewater treatment plants will all be enhanced primary treatment. Due to the N-Viro process, biosolids digestion was not necessary for beneficial reuse of the biosolids-based product. This facilitated a much lower cost wastewater treatment plant process. The existing Aerotech Park wastewater treatment plant will provide a mixture of untreated septage, digested biosolids and undigested biosolids. Dewatering at all wastewater treatment plants will be by Fournier Presses which yield dewatered cake at 28-38% total solids.
Approximately 35,000 tonnes on N-Viro Soil Amendment is produced per year. It is anticipated that 60% will be distributed for agricultural purposes and 40% iwill be used for topsoil manufacture, sod growing, horticulture and land reclamation.