Top Discharges

Streamgauges reporting the most discharge on the Cowlitz River

10 Day Trend

Discharge comparison for the highest gauges over the past 10 days

Expected Streamflow Ranges

Streamflow discharge range for this time of year

The Cowlitz River is a river in the state of Washington in the United States, a tributary of the Columbia River. Its tributaries drain a large region including the slopes of Mount Rainier, Mount Adams, and Mount St. Helens. The Cowlitz has a 2,586-square-mile (6,698 km2) drainage basin, located between the Cascade Range in eastern Lewis County, Washington and the cities of Kelso and Longview. The river is roughly 105 miles (169 km) long, not counting tributaries. Major tributaries of the Cowlitz River include the Cispus River and the Toutle River, which was overtaken by volcanic mudflows (lahars) during the ... Source: Wikipedia