Carlyle Lake Water Level
Carlyle Lake is at 444.52 ft today (Oct 31), 0.48 ft below its 445 ft full pool, down 0.10 ft this week.
Illinois · Kaskaskia River
Full pool is the summer level. Carlyle Lake is drawn down about 2 ft to roughly 443 ft over winter for flood storage, so a lower reading outside the summer season is usually scheduled rather than drought.
Get a text when Carlyle Lake crosses a level you pick →
Sponsor Carlyle Lake
Put your marina, real-estate, or local business in front of everyone checking this lake's level. One exclusive sponsor per lake.
Renews automatically each month or year until you cancel. Cancel anytime online. Terms · Manage or cancel · Questions?
Water level history
About Carlyle Lake
Carlyle Lake is a reservoir on the Kaskaskia River in Illinois, operated by U.S. Army Corps of Engineers. It's the largest man-made lake in Illinois. Its full summer pool sits at 445 ft above sea level. Live water levels come from the U.S. Army Corps of Engineers (CWMS) and update hourly.
Understanding Carlyle Lake's water level
Carlyle Lake is a flood control reservoir first. The Corps of Engineers dam stands 107 miles above the mouth of the Kaskaskia River, just upstream of the town of Carlyle, and it holds back about 2,717 square miles of drainage. Summer pool is 445 feet, and everything from there up to 462.5 feet is flood storage, roughly 675,000 acre-feet on top of the 242,600 the lake holds at normal level. Above 450 feet the water spreads onto flowage easement land that is private and closed to the public, which is why the Corps treats 450 as the level where recreation starts to suffer. Releases are limited by what the Kaskaskia below can carry: about 4,000 cubic feet per second stays inside the banks, and 10,000 is the maximum release. That ceiling is why high water lingers here. In May 2017 the pool crested at 456.58 feet on the 13th and was still above 454 ten days later with the gates passing 10,000 cfs. At 456 feet the lake covers about 46,500 acres, nearly double its summer footprint.
The level also follows a seasonal guide curve. The Corps holds 445 feet from May through November, then draws the lake down to a winter pool of 443 feet to make room for winter and spring runoff. The drawdown start can vary by two weeks either way, and release rates are set around downstream crop harvest, so the drop is spread across late fall. The curve steps up to 444 feet in April and back to 445 by May 1. Corps rangers say the lake is managed with IDNR so it does not fall more than a tenth of a foot per week during the spring spawn. The winter pool used to be deeper: a 1975 Illinois State Water Survey study describes an interim plan that dropped the lake to 440 feet each December, with a long range plan to use 443 instead to save water for navigation. That stored water matters. In December 2012, during the drought that left the Mississippi dangerously shallow, the Corps raised releases to 4,000 cfs to add about six inches of depth over the rock ledges at Thebes, one of the few Corps lakes able to help.
Clinton County residents organized in 1933 to push for a Kaskaskia valley project. Congress authorized a reservoir at Carlyle in the Flood Control Act of 1938, World War II stalled it, and construction finally began on 18 October 1958. The project was finished in April 1967 and the dam dedicated on 3 June 1967. Building it meant moving more than 600 graves from seven cemeteries, plugging 69 oil wells and relocating a railroad line; a rail embankment about three and a half miles long still crosses the lake between Keyesport and Boulder. North of those tracks the lake is flooded timber and brush averaging about three feet deep, while the lower two thirds is open water. That open water and the flat country around it make Carlyle a sailing lake. The Carlyle Sailing Association leases a 40 acre land based harbor inside Eldon Hazlet State Park, named for the Carlyle attorney who led the Kaskaskia Valley Association, and the two hosted sailing for the 1994 U.S. Olympic Festival. South Shore State Park, a satellite of Hazlet, covers about three miles of the southeast shore.
Carlyle Lake — frequently asked
What is Carlyle Lake's full pool level?
Normal summer pool is 445 feet, which the Corps holds from May through November. At that level the lake covers about 24,580 acres, runs roughly 15 miles long, averages 11 feet deep and reaches 35 feet at its deepest. Winter pool is 443 feet. Anything above 445 is flood storage, which extends to 462.5 feet before the reservoir would be using its surcharge pool.
What is Carlyle Lake's record high level?
459.8 feet on 18 May 2002, according to the Corps of Engineers' project data. That is nearly 15 feet above summer pool and less than three feet below the top of the flood control pool at 462.5. Later floods came close but stayed lower: the pool crested at 456.58 feet on 13 May 2017, and in April 2025 it reached about 451.9 feet with a forecast crest just under 452. The recent high in the gauge panel above covers only the last few years of Corps readings, so it falls short of the 2002 mark.
Why is Carlyle Lake lower in the winter?
The water control plan draws the lake from 445 down to a winter pool of 443 feet, starting in late fall with a variance of about two weeks either way. Those two feet open more flood storage for winter and spring storms. Releases during the drawdown are kept moderate and the Corps weighs downstream crop harvest when setting them, so the drop is gradual. In 2019 the drawdown ran at about 2,500 cubic feet per second.
When does Carlyle Lake go back to summer pool?
The guide curve steps from 443 feet to 444 in April and reaches 445 by May 1. Rangers say the Corps works with IDNR fisheries biologists so the lake does not drop more than a tenth of a foot per week during the spawn, and ideally rises slightly through April and May. A wet spring often fills it past 445 anyway, and the Corps then releases the excess.
Why does Carlyle Lake stay high so long after heavy rain?
The Kaskaskia below the dam can only carry about 4,000 cubic feet per second without leaving its banks, and the maximum release is 10,000. When inflows run near 30,000, as they did in May 2017, the lake stores the difference and drains slowly. Above 450 feet beaches, piers and regular ramps start closing; in April 2025 boaters used high water ramps at Dam West, Dam East, Coles Creek, Tamalco, Apache and Boulder.
Is Carlyle Lake the largest man-made lake in Illinois?
Yes. Both the Corps of Engineers and the Illinois Department of Natural Resources call it the largest man-made lake in the state. The acreage depends on the source: the Corps history page and IDNR park pages use 26,000 acres, while Corps flood notices give 24,583 acres at the 445 foot summer pool and the IDNR fishing profile lists 24,580.
How is the fishing at Carlyle Lake?
In IDNR's 2025 survey, channel catfish and white bass rated excellent, with white bass sampled at 160 per hour, up 65 percent from 2024. Crappie rated very good, and about half topped 10 inches. Biologists call it one of the best channel catfish lakes in Illinois. Bass must be 14 inches and crappie 10 inches to keep. Blue catfish and hybrid striped bass have been stocked since 2021 and are still developing.
Other lakes near Carlyle Lake
- Rend LakeIL
- Lake ShelbyvilleIL
- Lake BarkleyKY/TN
- Barren River LakeKY
- Blue Springs LakeMO
- Bull Shoals LakeAR/MO
See current levels for all 3 Illinois lakes and reservoirs →
Add this gauge to your website
Run a marina, boat rental, guide service, or real-estate site on Carlyle Lake? Put this free live-level widget on your page — just copy and paste the code: