Lake Ontario outflow sets records in 2019 Further increases expected in New Year
Outflows will be increased substantially in the coming days as efforts to remove water from Lake Ontario continue. Starting in January, following the end of navigation season, outflows will be increased as much as possible until ice formation resumes on the St. Lawrence River. A flow increase from 8,850 m3/s (312,500 cfs) to over 10,000 m3/s (353,000 cfs) may be possible in the coming days, with the exact amount depending on ice and water level conditions in the St. Lawrence River. Water levels downstream of the Moses-Saunders Dam, including around the Montreal area, are expected to rise, but will be monitored closely to ensure they are maintained below flood levels. Lake Ontario outflows were first set to record-rates in June as water levels of Lake Ontario reached a new daily record-high of 75.92 m (249.08 ft). This followed an unprecedented spring that saw record water levels and flows occurring across the Great Lakes and Ottawa River basins. High outflows from Lake Ontario continued through the summer, fall and early winter, resulting in more water released from Lake Ontario during the last seven months of 2019 than in any year since the start of records in 1900. The average outflow from June through December was 9,560 m3/s (337,600 cfs), the highest flow ever released over this period, and equivalent to removing nearly 9.1 m (30 ft) of water from Lake Ontario during this time. Full text of the announcement is attached and available online at: https://ijc.org/en/loslrb/lake-ontario-outflow-sets-records-2019-further-increases-expected-new-year. The International Lake Ontario-St. Lawrence River Board, in conjunction with its staff, continues to monitor conditions on an ongoing basis. Information on hydrologic conditions, water levels and outflows, including graphics and photos, are available on the Board’s website and posted to the Board’s Facebook page at https://www.facebook.com/InternationalLakeOntarioStLawrenceRiverBoard (English), and more detailed information is available on its website at https://www.ijc.org/en/loslrb.