History of the Lethbridge Wastewater Treatment Plant
In 1904, the sewer system consisted of 13 km of pipe that discharged directly into the river, then called the Belly River. By 1906, most of the homes behind the business districts were connected to the sewer system and by 1908 the City was willing to provide water and sewer service anywhere “if the people were willing to put up the cost, to be reimbursed when the number of connections gives the revenue” (Lethbridge daily Herald, September 29, 1908). In 1909, a further 3 km of sewer extensions was proposed, the majority of which had been requested through a petition.
By 1910, the City’s sewage was causing serious contamination of the river, resulting in a number of typhoid epidemics downstream. The City’s first wastewater treatment plant was designed and constructed, beginning operation at the end of 1912. Upgrades to increase the plant’s treatment capacity occurred in 1944 and 1959. In 1961, a second treatment plant was constructed to accommodate wastewater from the growing industrial base in North Lethbridge. The North plant was upgraded in 1966, 1972 and 1981. In 1987, in response to higher effluent quality standards imposed by Alberta Environment, the City began a $32,000,000 expansion of the North plant. The expansion was completed in 1989, at which time the South plant was decommissioned.
Between 1994 and 1998, a new treatment process was piloted and implemented. The process enhanced the plant’s ability to remove nitrogen and phosphorus (biological nutrient removal or BNR). The upgrade also added ultraviolet disinfection of the treated effluent.
In 2002, the plant was fitted with two cogeneration units. These units use digester gas to generate heat and electricity that are both used in the plant. In 2007, the blowers and aeration system were upgraded to increase the efficiency of the BNR process and reduce energy consumption.
Regional Wastewater received from the Town of Coalhurst in 2012. This marked the first new regional wastewater customer since the Agriculture Research Centre and Provincial Jail (1973), Fairview subdivision (1980), and the Rave Industrial Park (2000). Further, a wastewater forcemain from the Agropur cheese plant in Diamond City and the West Coast Reduction rendering facility north of the City is scheduled to be completed by the end of 2014.