River IL

Harrison Branch

Illinois • 40.2304, -90.8320

Reviewed mapped path Updated Dec 30, 2025

Checking mapped path coverage…

USGS and NOAA data is for informational purposes. Source notes

Length

12 mi

19 km

Elevation

837′ → 668′

170 ft drop

Stream Order

Medium River

Slope

0.27%

14.2 ft/mi

Drainage

21 mi²

53 km²

Avg Flow

-- cfs

0.9 mph velocity

Path to Mouth

1,336 mi

2,150 km to ocean

Classification

Tributary

Mid-reach

Elevation Profile

Water Quality

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

Detailed hydrology

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