Keeping above the water line
Determining water levels a matter of educated guessing
by Anne-Marie Jennings
NNSL (Apr 29/98) - Water may be of growing interest for Yellowknifers these days, but determining just how high our lakes and rivers will be this year is still a few days away.
Randy Wedel, client data services technologist with the hydrometric monitoring division of environment Canada's atmospheric environment branch, said there are no certainties when it comes to determining water levels.
"We've had a fairly warm winter," Wedel said. "But right now, it looks like it could be a typical year."
Wedel explained that water levels depend on a number of different factors, including temperature, amount of precipitation and how the ice is wearing.
"If the rain keeps up as it has for the past few days, the levels could be above normal," he said. "But things could cool off."
The hydrometric monitoring division compiles information on water levels. The data is released a few weeks before boating and fishing season gets under way, to help boaters and fishing enthusiasts better prepare for the season.
Wedel said the information is distributed widely throughout the city, to sporting goods stores, media, boat launch areas, and to many other locations to ensure the information needed is available to the public.
Information is collected by drilling a series of holes in the ice with an auger. Scientists can then measure water velocity, find an average, and determine the amount of water being discharged by the second.
"If you're standing on the edge of a river and looking over at the other side, the discharge would be the amount of water passing by you," Wedel explained."
In other parts of the NWT, the water level is both up and down. On the Mackenzie River at Fort Providence, there are about 10 metres of open water between the shore and the edge of the ice itself.
A measurement taken last Thursday showed the discharge was 6,800 cubic metres per second, with an average ice thickness of 1.3 metres.
The normal peak level for breakup at Fort Providence is around 12.2 metres, and the level recorded last Friday was 8.16 metres.