Satellite Monitoring of Red River Flooding in Near Real-time

By Marisa Brennan
April 2010

The Floodway control structure.

The Red River is a unique waterway — but it can also be a dangerous one. Flowing northward from Minnesota and North Dakota in the United States to Lake Winnipeg in Canada, the flat, shallow river floods each spring, costing millions in damages.

But every stage in the flood’s development is closely watched, thanks to satellite imaging. “The flood can move quickly, so we monitor changes in the flood extent every two to three days,” says Lori White, a physical scientist in geoinformatics at Natural Resources Canada’s Canada Centre for Remote Sensing (CCRS).

Lori is a member of the Emergency Management Team, which works with various partners to provide up-to-date monitoring of the flood, based on satellite images. “Our products are very unique. We deliver our flood-extent boundaries in near real-time, just four to six hours after we receive the satellite images,” says Lori.

Canada’s RADARSAT-1 and RADARSAT-2 satellites are specially programmed to collect the imagery. The satellites’ radar sensors see through obstructions, like rain or clouds, and they capture highly detailed views of current conditions. “Because we need to provide our products on a frequent and near real-time basis, it’s very important that we use RADARSAT satellite technology,” adds Lori.

The satellite data is transmitted to the CCRS receiving stations, where the imagery is processed and used to create various open-water flood products. As the flood progresses or abates, CCRS delivers updates to emergency personnel from a secure Internet map server.

For the Red River floods, the key user is the Manitoba Water Stewardship, which monitors water levels and provides flood forecasts. “The planning for satellite data acquisitions is closely aligned with their flood forecasts,” says Lori. She adds that several other partners are involved. “Coordination is required with Public Safety Canada, Manitoba Water Stewardship, Manitoba Emergency Measures Organization and other key organizations.” Details of the acquisition plan and the flood maps themselves are made available on the map server.

Emergency Response

The Red River flood extent.

CCRS has taken part in many other emergency response efforts, both within Canada and internationally. During the Red River flood of 2009 — the second largest since 1900 — various government departments and agencies accessed CCRS maps daily and used them as decision making tools.

In 2008, the Department of National Defence requested CCRS to monitor and map several sites: flood-prone areas in Afghanistan; the extensive flooding that resulted from a massive cyclone in Yangon, Myanmar; and the flood levels in Haiti following a succession of four major storms.

With its partners, CCRS will continue to closely monitor the Red River as the 2010 flood progresses northward. For more information about CCRS, visit the centre’s Web site.

To read about related articles, see Natural Hazards