NWT RESEARCH DATABASE

Regions: Inuvialuit Settlement Region

Tags: physical sciences, geology, coastal erosion, coastline

Objective(s): This projectÆs objective is to improve the knowledge of physical conditions in the coastal zone in order to help government agencies, corporations, and local residents understand, mitigate and reduce the impacts of natural changes and industrial or community development.

Project Description: This licence is being issued for the scientific research application no. 970. The western Arctic coast is among the most rapidly changing coastlines in the world and one of the most sensitive to climate change. This project’s objective is to improve the knowledge of physical conditions in the coastal zone in order to help government agencies, corporations, and local residents understand, mitigate and reduce the impacts of natural changes and industrial or community development. Research activities will be divided into 3 seasons and the methodologies are as follows. Winter (March-April) Activities will involve up to 8 people and last for up to 2 weeks. These will make use of industry camps with scientific research that coincides with oil industry activities in order make use of their roads and other infrastructure and minimize footprints and potential disturbance. Drilling and augering will take place in the winter and will employ hand tools. Collection of temperature data loggers from various previously drilled 10 m boreholes at the mouth and nearshore zone of Middle Channel. Ground penetrating radar (GPR) surveys will be undertaken in the winter from the ice surface using sleds pulled by human, snowcats or snowmobile. GPR surveys will be concentrated in the nearshore zone of the Mackenzie Delta, however some work will be conducted over some inland lakes in the region including Big Lake. Ground penetrating radar is a geophysical method that uses radar pulses to image the subsurface. This non-destructive method uses electromagnetic radiation in the microwave band (UHF/VHF frequencies) of the radio spectrum, and detects the reflected signals from subsurface structures. Spring Breakup (May/June) Mainly consists of helicopter reconnaissance work over the outer Mackenzie Delta. Current, water and sediment samples will be taken at various channel mouths during this time period. Time lapse cameras will be installed on industry wellheads and current and water level gauges will be deployed at various locations in the nearhore zone. If logistics permit, the researchers will undertake a 2-3 day small-boat survey of the seabed immediately after the ice breaks up to measure the depth of seabed disturbance due to current and strudel scours. Summer (June-August) Acoustic surveys will be undertaken in the open-water season during the months of June and August (before and after whaling season). Most will use very low energy echosounders as previously screened. Small boats up to 8 m in length will be the primary means of data collection during the open water season. Acoustic surveys will be concentrated in the nearshore zone, however if possible a number of lakes in the outer delta will also be surveyed. Spring break-up and summer camps will be small (2-4 people) and of short duration (less than 20 days) and will be supported by small boats (mentioned above) and helicopter. High resolution GPS surveys will take place at a number of coastal locations throughout the Mackenzie Delta, Richard Island, Tuktoyakuk Peninsula and Banks Island. Helicopter will be used as the primary means of transportation to and from each site. No more then a few hours will be spent at each site. The surveyor at each location will walk along the coastline recording positional data from a RTK-GPS system corrected to a local base station. Coastal survey work in Aulavik National Park is planned for summer 2009, with access in late July or early August via Twin Otter to Polar Bear Cabin and helicopter transportation to survey sites in the park. Throughout the year instrumentation deployed on the seabed will remain stationary and record changes using non-invasive and passive measurements for periods lastly several days or several months. Each logger is battery operated and no greater then 12 cm in diameter and housed within stainless steel 1-2 m mounting frames. Loggers will be deployed in locations and at depths to pose no hazard to shipping or boat traffic. A buoy will be placed at each location while it is on the seabed. Monuments for GPS surveys will involve jet drilling (summer only) to depths of 10-30 m in order to install steel pipe or wooden monuments, generally at sites where previous research, monitoring, or exploration activity has taken place. The monuments will be visible above the ground surface (approximately 1 m) and will have a mounting bracket attached to them. Radar reflectors may be deployed at these locations for periods of months to years in order to help validate remotely sensed data and investigate land subsidence. The radar reflectors are 1 m triangles made of a metal mesh. Temperature measurements in boreholes will be made by installing 2 inch plastic casing into a jet-drilled hole and threading a series of up to 10 thermistors on an electrical cable into the borehole. A data logger will be installed to capture temperature readings several times per day at each depth in the borehole. The project will use previously proven and approved methods only. Field surveys will be undertaken in consultation with HTCs in order to ensure the timing of surveys is compatible with local use of the land and water. The researchers will employ local personnel as wildlife monitors, field assistants and guides as required by logistics and field safety concerns as they have done in the past. The fieldwork for this study will be conducted in 40 research sites in the Mackenzie Delta (solely in the Inuvialuit Settlement Region) from March 22 to August 31, 2009.