Control Board continues following regulation plan
The International St. Lawrence River Board of Control (Board) recently reviewed conditions in the Lake Ontario-St.Lawrence River system. The Board has decided to continue to release outflows in accordance with the regulation plan as much as possible. Outflows may be adjusted to avoid flooding or other extreme water level conditions downstream, or to meet critical hydro power and navigation needs.
The supply of water received by Lake Ontario was slightly above average in March, due to the earlier than usual melt of the snow that had accumulated in the watershed. Outflows were about 2% above average. Lake Ontario’s level rose in March by 12 cm (4.7 in), compared to an average 15 cm (5.9 in) rise. Water supply conditions in April, to date, have been very dry. Water levels have only risen slightly this month. The level is presently at 74.67 m (244.98 ft) which is about 22 cm (8.7 in) below average and 48 cm (18.1 in) below last year at this time. There is almost no risk of Lake Ontario reaching its upper level limit in 2010; there is a small but growing risk of low Lake Ontario levels in the fall. Water levels on Lake St.Lawrence have generally been near average the past several months.
Levels near Montreal have been below average for the past several months, but well above chart datum. The freshet of the Ottawa River was smaller and earlier than average so the Board did not need to reduce Lake Ontario out flows to prevent flooding downstream. The level at the port of Montreal is presently at 6.25 m (20.51 ft) which is about 133 cm (52 in) below average and 94 cm (37 in) below last year at this time. If conditions remain dry, water levels in the port of Montreal may fall below chart datum this summer.
The Board, in conjunction with its staff, is monitoring the situation carefully and is prepared to take action if required. The Board will assess the situation again in about 4 weeks, or earlier if there is a significant change in conditions.
Contacts:
Gail R. Faveri: (905) 336-6007; gail.faveri@ec.gc.ca
John Kangas: (312) 353-4333; John.W.Kangas@usace.army.mil
The International St. Lawrence River Board of Control was established by the International Joint Commission in its 1952 order of approval. The Board’s main duty is to ensure that outflows from Lake Ontario meet the requirements of the IJC order; it also develops regulation plans and conducts special studies requested by the IJC. For more information, visit www.ijc.org/loslrb or www.ijc.org (> Boards > International St. Lawrence River Board of Control). To receive a weekly e-mail about water levels and flows in the Lake Ontario–St. Lawrence River system, please send a blank e-mail message to stlaw-L-subscribe@cciw.ca, with the word ’subscribe’ in the title and body of your message.