The North Fork travels northwest until it reaches the small town of Dinsmore, where it starts flowing west.

Road construction and poor logging practices, particularly historical, have increased erosion, leading to excessive sediment buildup in the river and its tributaries.

In addition, gravel mining, particularly at the confluence of the Van Duzen and Eel River, has increased erosion, affected channel alignment and may block fish migration.

It is named for James Van Duzen a member of the Josiah Gregg exploring party that first traveled to Humboldt Bay overland in 1849.

[5] The deaths of 14 dogs after going swimming have occurred in the last twenty years due to cyanobacteria in blue-green algae on the Big Lagoon, South Fork Eel River or the Van Duzen River during times of warm weather and low water flow.