Lake Ontario Outflow Changes

Outflows from Lake Ontario are established by the International Lake Ontario - St. Lawrence River Board in accordance with the current regulation plan and the International Joint Commission's Orders of Approval. The table below displays the outflow changes that have occurred this year. All flows are reported in cubic metres and cubic feet per second.

The average Lake Ontario outflow is expected to be 8090 m³/s (285,700 cfs) for the coming week, which is the amount specified by the regulation plan. The actual flow during the week may vary depending on conditions in the St. Lawrence River.

DATE	HOUR/HEURE	OUTFLOW/DÉBIT	OUTFLOW/DÉBIT
(YYYY-MM-DD)	(HHMM)	(m³/s)	(cfs)
2021-05-15	0001	8,090	285,700
2021-05-08	0001	8,070	285,000
2021-05-01	0001	7,920	279,700
2021-04-24	0001	7,410	261,700
2021-04-16	2101	7,350	259,600
2021-04-15	2101	7,820	276,200
2021-04-10	0001	7,420	262,000
2021-04-03	0001	7,980	281,800
2021-03-20	0001	7,380	260,600
2021-03-13	0001	8,000	282,500
2021-03-06	0001	8,080	285,300
2021-03-01	0001	8,140	287,500
2021-02-21	1501	8,600	303,700
2021-02-20	1201	8,400	296,600
2021-02-19	1201	8,000	282,500
2021-02-18	1801	7,600	268,400
2021-02-18	0701	7,400	261,300
2021-02-17	1101	7,000	247,200
2021-02-16	1401	6,600	233,100
2021-02-12	1401	7,000	247,200
2021-02-11	1601	7,400	261,300
2021-02-10	1901	8,300	293,100
2021-02-09	2001	8,500	300,200
2021-02-05	1801	8,800	310,800
2021-02-04	1201	8,200	289,600
2021-02-03	1401	7,700	271,900
2021-02-01	1501	7,100	250,700
2021-01-31	1801	6,900	243,700
2021-01-28	1601	7,200	254,300
2021-01-26	1001	7,700	271,900
2021-01-24	1701	7,200	254,300
2021-01-23	1701	8,400	296,600
2021-01-19	1501	9,200	324,900
2021-01-16	1701	9,400	332,000
2021-01-14	1201	9,200	324,900
2021-01-12	1201	9,500	335,500
2021-01-09	1501	9,400	332,000
2021-01-07	1301	9,300	328,400
2021-01-05	1001	9,200	324,900
2021-01-04	1701	9,400	332,000
2021-01-03	1301	9,500	335,500
2021-01-01	0801	9,400	332,000
2020-12-26	0001	8,090	285,700