Creek IL

Courtois Creek

Illinois • 37.8828, -91.1081

Reviewed mapped path Updated Dec 30, 2025

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USGS and NOAA data is for informational purposes. Source notes

Length

39 mi

62 km

Elevation

1,231′ → 639′

591 ft drop

Stream Order

Medium River

Slope

0.29%

15.3 ft/mi

Drainage

220 mi²

570 km²

Avg Flow

-- cfs

1.1 mph velocity

Path to Mouth

341 mi

549 km to ocean

Classification

Tributary

Mid-reach

Elevation Profile

Water Quality

Data from EPA Water Quality Portal (USGS, EPA, state agencies).

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Data from USGS & NOAA for informational purposes only. Read source and safety notes

Rain Radar