River OH

Grassy Fork

Ohio • 39.1358, -84.0142

Reviewed mapped path Updated Dec 30, 2025

Checking mapped path coverage…

USGS and NOAA data is for informational purposes. Source notes

Length

37 mi

59 km

Elevation

864′ → 452′

412 ft drop

Stream Order

Large River

Slope

0.21%

11.2 ft/mi

Drainage

35 mi²

90 km²

Avg Flow

-- cfs

1.4 mph velocity

Path to Mouth

780 mi

1,255 km to ocean

Classification

Tributary

Mid-reach

Elevation Profile

Water Quality

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

Detailed hydrology

Explore the interactive map

Load the reviewed river path, linked gauges, access points, and zoom-aware map detail.

Loaded on demand to keep this free public service fast.

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