| Abstract/Description or Keywords |
The Lakes District does not have water bodies with site-specific water quality objectives, and there is little or no monitoring data for most drinking water sources. In 2002-03 a comprehensive sampling program was implemented for a number of drinking water sources including Burns Lake, Francois Lake, Babine Lake and Burns Lake Rural Area groundwater. In August and October 2002, and April and August 2003, drinking water samples were collected to investigate the quality of Lakes District drinking water. Five samples were collected from each site within a 30-day period in each sampling season (note: not all sites were monitored in each season). The samples were analyzed for three microbiological indicators (fecal coliforms, E. coli and enterococci), colour and turbidity. In each season, one sample from each site was analyzed for a comprehensive range of physical and chemical parameters to determine overall water quality and identify potential contamination. Lab results were compared to MoE approved and working guidelines for drinking water quality. In each season, 90th percentiles were calculated for the microbiological indicators and the results were compared to the Disinfection Only guideline level (which is the minimum treatment requirement for surface water sources under the Drinking Water Protection Regulation). For groundwater sites around Burns Lake, the No Treatment guideline was applied. • Burns Lake has shown eutrophic characteristics and variable water quality in recent years, but it continues to be a drinking water source for some lakeshore residents. Source water was monitored at two intakes in 2002-03 to investigate seasonal patterns in water quality, and determine risks associated with eutrophication (high nutrient levels), failing lakeside sewage disposal systems and agricultural activities. o All three microbiological indicators were detected. Fecal coliform and E. coli 90th percentiles met MoE guidelines, but the enterococci guideline was not met in August. o Most samples had turbidity values that met the MoE guideline of ≤ 5 NTU, but no samples met the 15 TCU guideline for colour. o Phosphorus values were consistently above guideline levels, and excessive plant growth and periodic algae blooms are possible. Other physical and chemical parameters were below MoE drinking water guidelines. • Francois Lake drinking water intakes have not been monitored by MoE in the past; a Lake Management Plan for Francois Lake identified possible contamination sources including residential development (fertilizers and septic systems), agriculture, forestry, mining, infrastructure, and boat sewage discharges. Four intakes were monitored in 2002-03. o Microbiological indicators were occasionally detected in low concentrations. Most sample sets met MoE drinking water guidelines. o Turbidity and colour were well below MoE guideline levels. o Manganese exceeded the aesthetic drinking water guideline in one sample; other physical and chemical parameters were below guideline levels. • Babine Lake has not been monitored by MoE in the past, but a complaint about possible sewage contamination in the Topley Landing area prompted limited sampling in October 2002. Samples were collected at two intakes to investigate this potential source water contamination issue o Enterococci were not detected, but fecal coliforms and E. coli were present in some samples from both sites. All microbiological indicator guidelines were met. o Turbidity values easily met the MoE drinking water guideline. Colour values did not meet the guideline in two of ten samples, and other physical and chemical parameters met guideline levels. o Phosphorus exceeded the guideline level at the site near the alleged contamination. Slightly elevated levels of bacteria and phosphorus at this site suggest that source water contamination is possible, but further investigation is required. • Groundwater is a common drinking water source for residents living in or near the Village of Burns Lake. Groundwater sampling was conducted from wells in Gerow Island and Byetown subdivisions to investigate groundwater quality and determine its suitability as a desirable alternative to surface water intakes: o Low concentrations of enterococci were found in one of 15 samples from Gerow Island and five of nine samples from Byetown, exceeding the MoE (No Treatment) guidelines for enterococci. o Turbidity values at both sites were variable, and the drinking water guideline was often exceeded. Most samples met the guideline for colour. o Iron and manganese commonly exceeded aesthetic guideline levels, but the observed concentrations do not pose a risk to human health. o Further sampling is recommended to investigate water quality issues at the Byetown well. Based on monitoring conducted in 2002-2003, we recommend that: • The Ministry should continue to collaborate with the Northern Health Authority (NHA), local water suppliers, and other agencies interested in water quality in the Skeena Region. • Monitoring of enterococci and E. coli levels (in addition to fecal coliform concentrations) should continue and these results should be included in water quality objectives development and updates. • Future monitoring programs should include sampling in a range of (weather and flow) conditions to investigate variations in water quality. • Through collaboration with NHA staff, residents and other users of land in (drinking water) watersheds should be made aware of the risks that land use activities pose on nearby surface water sources and groundwater wells. Residents should be reminded of the need to disinfect surface water supplies, and lake water users should be encouraged to extend intake pipes further into the lake to minimize potential sources of contamination. Groundwater users should be reminded about the importance of adequate well head protection. • Drinking water source quality data should be made readily available to any interested parties • Provisional water quality objectives for Burns Lake should be re-visited with a more comprehensive sampling program, and potentially adopted. • Babine Lake sampling should be expanded to include other sites to determine whether or not the sampling results from 2002 are indicative of sewage contamination. • Byetown groundwater sampling should continue at the established site and be expanded to other sites in the subdivision to investigate water quality issues described in this report. |
