Citation | Epps, D and Phippen, B. 2011. Water quality assessment and objectives for Comox Lake, Technical Report. BC Ministry of Environment. |
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Organization | BC MoE |
URL | http://www.env.gov.bc.ca/wat/wq/comox/comox-technical-may2011.pdf |
Abstract/Description or Keywords | This document presents a summary of the ambient water quality of Comox Lake, British Columbia, and proposes water quality objectives designed to protect existing and future water uses. The water quality assessment for the lake and an evaluation of the watershed form the basis for the objectives. Comox Lake is a large lake, with a surface area of 2,100 ha, located near the village of Cumberland, BC. Drinking water supply is an important water use of this watershed. The Comox Valley Regional District withdraws drinking water from the Puntledge River downstream from Comox Lake, and the water quality of Comox Lake has a large influence on the quality of Comox Valley drinking water. BC Hydro has a dam at the outlet of Comox Lake. The lake water levels are controlled to ensure sufficient flows for the hydroelectric project, drinking water use and fisheries use downstream in the Puntledge River. Comox Lake also provides significant recreational opportunities (fishing, swimming, camping and boating) and fish and wildlife habitat. These activities, as well as forestry, residential and historical mining activities, all potentially affect water quality in Comox Lake. Water quality monitoring was conducted between 2005 and 2008. The results of this monitoring indicate the lake is oligotrophic and the overall state of the water quality is very good. All chemical, physical and biological parameters meet provincial water quality guidelines with the exception of microbiological indicators which exceeded drinking water guidelines on occasion in the outlet basin. A microbial source tracking study prepared for the Comox Strathcona Regional District in 2005 found that the predominant sources of fecal coliforms near the lake outlet were attributable to deer, dogs and seagulls (Clayton, 2005). In order to maintain and protect the water quality in Comox Lake, ambient water quality objectives were set for temperature, dissolved oxygen, water clarity (Secchi depth), total phosphorus, chlorophyll a, turbidity and E. coli. Future monitoring recommendations include attainment monitoring at all three deep basin sites, every 3-5 years, depending on available resources and whether activities, such as forestry or development, are underway within the watershed. This monitoring should be conducted for one year on a quarterly basis and also include microbiological indicators at the seven perimeter sites during the summer low flow and fall flush period (five weekly samples in 30 days). In addition, future monitoring should be conducted downstream of Comox Lake in the Puntledge River at the CVRD water intake location. |
Information Type | report |
Regional Watershed | Vancouver Island South |
Sub-watershed if known | Comox Lake |
Aquifer # | |
Comments | |
Project status | |
Contact Name | Deborah Epps |
Contact Email | [email protected] |