CountiesMacon County
IllinoisReservoirMacon County
Lake Decatur
Lake Decatur is a 2,718-acre reservoir on the Sangamon River in Illinois. The lake is in Macon County. Management is in the hands of City of Decatur (Water Resources / Lake Services).
Coordinates39.8167, -88.9333
Surface area2,718 acres
RiverSangamon River
Managed byCity of Decatur (Water Resources / Lake Services)
Swimming beaches on Lake Decatur
No named swimming beach is mapped yet for this lake. Access is through agency day-use areas and boat ramps listed below. We add beach pages only when we can confirm a name, coordinates and an operating agency.
Lake Decatur on the map
Lake center, swimming spots and access points.
Weather and water temperature
Air temperature and wind from Open-Meteo. Water temperature only when the lake has a public sensor.
Weather data by Open-Meteo
Lake Decatur: beaches, ramps and water level
The center of the lake is at 39.8167, -88.9333. Outflow feeds the Sangamon River. It lies at roughly 613 feet of elevation.
Lake Decatur has no catalogued swimming beach in the sources we read, so plan around the managing agency's own facilities. Shoreline access on lakes like this one is often informal and unsigned.
Water level is missing from this page on purpose: no public feed covers Lake Decatur. For a lake this size, the park office is the fastest way to learn how the water sits today.
Algae blooms are seasonal and local: look for posted signs at the ramp or park entrance. Season dates vary by park; the operating agency publishes them each spring. Water temperature is not measured at this lake by any public agency we read.
The closest lakes in this guide are Lake Shelbyville (Illinois, 26 mi), Lake Springfield (Illinois, 36 mi) and Lake Mattoon (Illinois, 40 mi). Illinois has 9 lakes on this site in total.
Questions about Lake Decatur
Is there a beach at Lake Decatur?
No named swimming beach appears in the federal and state datasets this guide reads. Check the operating agency for day-use areas on the ground.
How big is Lake Decatur?
About 2,718 acres.
What other lakes are near Lake Decatur?
The closest in this guide is Lake Shelbyville, about 26 miles away in Illinois.
Lakes near Lake Decatur
Other lakes in this guide, ordered by distance.
Clinton Lake
Clinton Lake is a 7,000-acre reservoir on the Wakarusa River in Kansas. The lake is in Douglas County. It is managed by USACE…
Reservoir
Lake Shelbyville
Lake Shelbyville is a 11,100-acre reservoir on the Kaskaskia River in Illinois. You will find it in Moultrie County. Management…
Reservoir
Lake Springfield
Lake Springfield covers about 3,965 acres of the Sugar Creek in Illinois. Its shoreline falls inside Sangamon County. Management…
Reservoir
Carlyle Lake
Fed by the Kaskaskia River, Carlyle Lake holds roughly 26,000 acres of water in Illinois. Its shoreline falls inside Clinton…
Reservoir1 beach
Rend Lake
Rend Lake covers about 18,900 acres of the Big Muddy River in Illinois. You will find it in Franklin County. Management is in the…
Reservoir
Lake Freeman
Lake Freeman is a 1,547-acre reservoir on the Tippecanoe River in Indiana. The lake is in White County. Indiana DNR manages it.
Reservoir
Explore around Illinois
Sources
Every figure on this page comes from one of these public sources.