River WA

Copalis River

Washington • 47.2187, -124.0552

Hydrography profile Updated Dec 30, 2025

Checking mapped path coverage…

USGS and NOAA data is for informational purposes. Source notes

Length

25 mi

41 km

Elevation

336′ → 7′

329 ft drop

Stream Order

Medium River

Slope

0.25%

13.0 ft/mi

Drainage

39 mi²

101 km²

Avg Flow

-- cfs

1.1 mph velocity

Path to Mouth

25 mi

40 km to ocean

Classification

Tributary

Mid-reach

Elevation Profile

Water Quality

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

Data from USGS & NOAA for informational purposes only. More