Illinois River Lockport LD water level history

Daily records since 2011 · Level today: 576.30 ft

Highest on record

1,889.87 ft

Mar 31, 2011

Lowest on record

0.00 ft

Feb 6, 2012

Today

576.30 ft

Oct 21, 2026

Years of data

since 2011

In short

Across 14 complete years, 2012 had the lowest average level (545.99 ft) and 2023 the highest (575.81 ft).

On average the lake is lowest in February (553.98 ft) and highest in April (581.97 ft).

Loading chart…

Measured Normal range for the date (middle 50% of past years)

Years ranked by their lowest daily level.

Year	Average	Low	Low date	High	High date
2026 (294 days)	575.76	570.80	Sep 20	580.11	Jul 15
2025	575.78	572.17	Aug 19	577.30	Apr 3
2024	575.77	573.38	Jul 15	579.99	Sep 15
2023	575.81	572.62	Jul 2	576.38	Jun 4
2022	575.71	573.11	Mar 31	576.27	Aug 24
2021	575.55	571.38	Jun 28	576.25	Dec 25
2020	575.48	569.30	Apr 30	579.61	Jun 8
2019	575.33	570.57	May 2	576.30	Jan 19
2018	575.76	571.33	Feb 20	576.40	Sep 28
2017	575.41	569.47	Apr 30	576.53	Dec 21
2016	575.47	570.23	Jul 24	576.12	Feb 14
2015	575.51	570.47	Sep 18	576.18	Apr 18
2014	575.36	569.18	Jul 1	576.33	Feb 13
2013	575.42	571.53	Apr 19	577.65	Jul 1
2012	545.99	0.00	Feb 6	576.75	Mar 5
2011 (277 days)	596.17	571.59	Jul 23	1,889.87	Mar 31

Levels in feet. Partial years show the number of days with data.

Month	Average	Lowest	Highest
January	575.63	573.66	576.35
February	553.98	0.00	576.36
March	579.62	175.72	1,889.87
April	581.97	569.30	1,888.68
May	575.37	570.57	576.43
June	575.46	571.19	579.61
July	575.53	569.18	580.11
August	575.55	569.87	576.27
September	575.63	570.47	579.99
October	575.55	571.11	577.97
November	575.76	573.91	576.38
December	575.70	571.17	576.53

Daily levels as CSV (5,648 rows; credit the original agencies listed below)