River IL

Dennis O'Nan Ditch

Illinois • 37.5997, -88.0873

Hydrography profile Updated Dec 30, 2025

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USGS and NOAA data is for informational purposes. Source notes

Length

5 mi

8 km

Elevation

362′ → 326′

35 ft drop

Stream Order

Medium River

Slope

0.13%

6.8 ft/mi

Drainage

72 mi²

187 km²

Avg Flow

-- cfs

1.1 mph velocity

Path to Mouth

115 mi

186 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