NWT RESEARCH DATABASE

Regions: Dehcho Region

Tags: water quality, environmental impact, petroleum industry, biology, fish habitat, hydrology, traditional knowledge, industrial development, pipeline corridor, fish population, water level, watercourse crossing, stream flow, environment, Mackenzie Gas Project, hydrogeology, environmental protection plan

Objective(s): Imperial Oil Resources, CONOCO Canada Resources Limited, Shell Canada Limited, and ExxonMobil Canada initiated a number of Baseline Biophysical Studies in the NWT during 2001 as part of a feasibility study for the Mackenzie Delta Gas Opportunity. These studies are being continued in 2002. Local knowledge and technical/scientific research, in combination with a synthesis of existing technical information, is being used to develop a suitable knowledge base for planning, assessment of impacts and development of environmental protection plans. TERA Environmental Consultants (TERA), in association with Kavik-AXYS Environmental Consulting Ltd., AMEC Earth & Environmental Ltd., and Golder Associates Ltd., has been retained to conduct the baseline studies. This portion of the project is the aquatic studies in the Deh Cho Region, and includes fish and fish habitat, hydrology, water quality and hydro-geology studies. Traditional knowledge as it relates to aquatic systems will also be collected. This will help complete the overall record of fish species and habitat within the study area, as well as identifying long term trends in fish population, water levels and changing stream channels.

Project Description: The research team proposes to collect information about fish habitat features and use on watercourse crossings located within the tentative pipeline corridor in the Deh Cho Region. All aquatic studies will be conducted by three or four-person crews. Each crew will include a local researcher or community representative. Depending upon accessibility, sites will be accessed by helicopter and an inflatable boat. Where conditions permit, sites will be accessed by 4 x 4 truck, snowmobile or quad. Surveys of fish and fish habitat will be made at 35 permanently flowing watercourses. In addition, studies will be conducted at 15 intermittent or seasonal streams to determine the presence of spring spawning fish. Detailed habitat surveys in permanently flowing watercourses will include: (1) bathymetric features (depth, width, water surface elevation,etc.); (2) hydrologic features (presence of inflow or out flow, flow velocity and characteristics, stage, discharge, freezing characteristics, etc.); (3) water quality (temperature, pH, dissolved oxygen, turbidity/TSS, etc.); (4) composition of channel-bed material (% silt, sand, gravel, cobble, boulder, etc.); and (5) shoreline features (height, slope, vegetative cover, % under cut etc.). Although the baseline studies will focus on the collection of fish habitat data, some sampling of fish will be required. Fish sampling will be done primarily to confirm historic information, confirm fish presence/absence and to confirm habitat use. Non-lethal fishing methods such as electrofishing, seining, or setting baited minnow traps will be used. All fish captured will be identified to species and life stage, measured to fork length and released at the location where they were captured. Traditional knowledge as it relates to aquatic systems will also be collected. This will help complete the overall record of fish species and habitat within the study area, as well as identifying long term trends in fish population, water levels and changing stream channels.