Home Municipal Services Water & Sewer Utilities Okotoks Sanitary Sewage System
Okotoks Sanitary Sewage System
The sanitary sewage system is opperated as a self sufficient rate based utility system. It consists of 64.7 kms of sewer mains, 781 utility holes, 4628 service lines, and a state-of-the-art Wastewater Treatment Plant. In March 2005, Okotoks' growing population posed a concern as the Town's existing wastewater plant was fully loaded and had discharge limits nearing regulatory upper limits. To address the situation, the Town in partnership with EPCOR Water Services invested in a new 24.5 million litre per day tertiary wastewater treatment plant that utilizes innovative technologies including; a new bioreactor that doubles flow capacity, an ultraviolet light disinfection system, a biological nutrient removal process and a method to compost of the systems biosolids sludge.
In order to complete the $11.2 million expansion at less than half of the initial estimated costs, EPCOR took advantage of existing facilities and buildings to save on cost and land requirements.
In-Vessel Bio-solids Composting an Innovation in Wastewater Treatment
A centerpiece of Okotoks' sustainable development initiative has been the conversion/expansion of its wastewater system into an Integrated Waste Water Treatment Plant (WWTP) that processes sewage into compost. Think of it as a huge composting toilet.
As the first municipality in Canada to generate compost from sewage, the $3.7 municipally-funded construction project (completed 2004) represents a revolution in thinking about wastewater treatment - a move from the existing paradigm of "waste disposal" landfilling and land spreading sludge to "resources recovery" and zero impact - with a composted product that is in demand and for sale. Removal of solids from the front end of the treatment process allow for greater efficiency in treatment of liquids, discharging effluent that meets or exceeds upstream water quality standards and contributing to maintaining and enhancing the aquatic health of the Sheep River.
The system takes a variety of proven bio-solids removal and treatment technologies and bundles them into an engineered system to achieve better results than today's common conventional wastewater treatment systems can provide.
The Positive Results:
500% decrease in BOD
(Biochemical Oxygen Demand - a common environmental procedure for determining the extent to which oxygen within a sample can support microbial life).
300% decrease in TSS (Total Suspended Solids)
30% reduction in energy use
Greenhouse gas emissions reduced by 28% (620 tonnes annually)
4200 tonnes compost per year created.
BOD and TSS reduced by a further 25%
Ammonia reduction - 66% summer / 80% winter
Phosphorous removal to below 1.0 mg/l
Removal of chlorine from system (UV disinfection replacement)
Additional heat energy recovery (eg. greenhouse)
The compost is currently initially processed and stored on site for a short period of time and then trucked out to a waste management facility where they have constructed a licensed composting facility. Material will be further processed for approximately 6 months from this location. The Town is currently in the process of forming a relationship with the Regional Services Commission to market and sell the product produced (Grade A Commercial Compost).
Removal of solids from the front end of the treatment process allows for greater efficiency in treatment of liquids, discharging effluent that meets or exceeds upstream water quality standards and contributes to maintenance and enhancement of the aquatic health of the Sheep River.