Field monitoring and performance evaluation of the Whitehorse sewage lagoon

• Published in: Canadian Journal of Civil Engineering
• Main Authors: Whitley, G., Thirumurthi, D.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1992
• Subjects: General Environmental Science; Civil and Structural Engineering; Yukon; Canada; Whitehorse
• Online Access: http://dx.doi.org/10.1139/l92-086; http://www.nrcresearchpress.com/doi/pdf/10.1139/l92-086

The treated effluent from a four-cell (predominantly anaerobic) sewage lagoon in Whitehorse, the Yukon Territory, Canada, does not meet the quality guidelines of the Yukon Territory Water Board. The inflow rates and the biochemical oxygen demand (BOD 5 ) and suspended solids (SS) on 24-h composite samples of municipal wastewater influent and effluent were monitored from August 1989 to September 1990 to assess the performance and to estimate the first-order BOD 5 removal coefficient, K. This study in northern Canada included a measurement of solar energy (photosynthetically active radiation, PAR) using a quantum radiometer which recorded the duration as well as the magnitude of PAR, for 1 year. Moreover, pH, conductivity, and temperature of influent and effluent, coliforms and chlorophyll of effluent, as well as dissolved oxygen (DO), temperature, and SS of the lagoon contents at various depths were recorded. The value of K ranged from a low of 0.036/d in December (at 2.4 °C) to a high of 0.097/d in October (at 5.2 °C). The monthly average effluent BOD 5 exceeded the Yukon Water Board's permissible limit of 45 mg/L during the months of January, February, March, June, and July. Key words: cold climate anaerobic lagoon, photosynthetically active radiation (PAR), lagoon short-circuiting, performance data, northern Canadian sewage lagoon, Yukon Territory, first-order BOD 5 removal coefficient, chlorophyll.