Scope of Services:
Water quality and fish populations in John Hart Reservoir were examined within the impact assessment and mitigation analysis for the John Hart Replacement Project (replacement of penstocks, power generation works, and other infrastructure). Limnotek worked within a large team managed by Hemmera who was the lead consultant. Baseline data collection included hydroacoustics for measuring fish population size, gill netting for apportionment of fish population by species, fish biomass measurement, assessment of links between food ingestion by fish and food availability, development of rating curve for reservoir volume based on water surface elevation, measurement of river and reservoir hydrology, measurement of habitat areas, characterization of sediment content and change to water quality from sediment resuspension, analysis of density stratification that affects temperature for fish and water supplies, and analysis of trophic state for assessing water quality. Effects assessment and mitigation planning conducted by Limnotek included sediment resuspenion and settlement, nitrogen enrichment from blasting, acid rock drainage, change in pH in water from concrete placements, gas pressure in water, change in water temperature, and detailed study of risk of fish entrainment using state of science DNA tracking. Spin off tasks involved interpretation of water quality resulting from infrastructure changes for the City of Campbell River water supply that comes from John Hart Reservoir.
Relevance of the Project:
The John Hart power facilities are being replaced. Limnotek provided the water quality and fish population assessment for John Hart Reservoir as required for the environmental impact assessment and design of mitigation works.