River CA

Kopta Slough

California • 39.9395, -122.0967

Reviewed mapped path Updated Dec 30, 2025

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USGS and NOAA data is for informational purposes. Source notes

Length

6 mi

9 km

Elevation

0′ → 0′

0 ft drop

Stream Order

Stream

Slope

0.00%

0.0 ft/mi

Drainage

9,339 mi²

24,189 km²

Avg Flow

-- cfs

0.7 mph velocity

Path to Mouth

220 mi

355 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