Zebra mussels keep flatwater course
YOU ASK. WE ANSWER. Q: What keeps the Flatwater course, or the old canal so clear? Apparently there are no tubes at the “plug ” near Dain City to keep the water flowing like it used to from Port Colborne. A: The clear water at Welland’s International Flatwater Centre is
an all-natural phenomenon.
Steve Miller, manager of water resources and restoration for the Niagara Peninsula Conservation Authority, explained there are two main reasons the water is so clear there.
The old Welland Recreational Canal is separated into two parts by a “plug” of land which was created to allow rail traffic to move east and west. Both the canal’s south
portion and north portion, where the Flatwater centre is located, are
connected to the current Welland Canal. That means they’re filled with
Lake Erie water.
Although the plug exists, Miller said the north and south portions are big enough that the water circulates like in mini lakes and doesn’t
stagnate.
The clarity of the water is also caused by zebra mussels which established themselves in the canal about 15 or 20 years ago.
Miller said zebra mussels can be a nuisance clogging intakes and infrastructure. But in the case of the Welland Recreational Canal they serve to filter out the water, making it clearer and allowing aquatic plants to grow, providing forage and food for fish. “They’ve cleaned up the water
in the recreational canal,” he said. “More light can penetrate through and you see plants have the ability to grow far better than they used to in the past.”
Q: Would you let me know why the Welland River flows down towards Niagara and sometimes reverses and why this is done?
A: The water in the Welland River has been flowing in two different directions since 1921. We once again turned to Niagara Peninsula Conservation Authority’s
Steve Miller to explain the bizarre occurrence.
Miller, the manager of water resources and restoration, said the Welland River winds its way east 132 kilometres from an area near the Hamilton airport to Niagara Falls.
Around West Lincoln the river flattens out. For about 60 kilometres it only falls 12 feet. The Welland River used to flow into the Niagara River but in 1921 Ontario Hydro dredged a portion and constructed
the Queenston-Chippawa power canal which runs north. The Welland River now flows east into that canal.
Water from the Niagara River flows west into the canal.
The canal sends water north into the Sir Adam Back hydro generating station.
During tourism season, an international treaty between Canada and the U.S. requires 100,000 cubic feet per second of water to go over falls, in the Niagara River, during the day.
But at night and in non-tourist season, between October and April, the flow over the falls is reduced by
half with gates. That raises the water level in the Niagara River upstream by three feet, so more water can be sent towards the Queens ton Chip paw a power canal. As the water rushes towards the power canal, the tidal wave overwhelms the average flow in the Welland River and things there start flowing backwards. “It’s this attempt at night to send
more water into the power canal that causes the reversal of the flows in the Welland River because the Welland River is so flat,” Miller said.
Miller said it takes the front wave 12 hours to reach Port Davidson in West Lincoln, so even though the gates are closed at night, people generally see the flow reversal during the day. The reversal travels about 60 kilometres.
Send your queries to Karena Walter by email at kwalter@postmedia.com; by Twitter @karena_ standard or through Facebook at www.facebook.com/ karenawalter