SR 546 - Kamm Ditch - Fish Passage - Complete April 2025

Kamm Ditch, located on SR 546 near the intersection at Northwood Road (milepost 4) in Lynden, is a drainage channel that flows generally north to south. The previous culvert was a reinforced concrete 6-feet by 4-feet box culvert with two wingwalls and extends beneath the highway approximately 33 feet. This project improved fish passage by attaching four 9 feet by 11 feet winged walls to the precast culvert. The precast culvert requires modifications. The fish habitat gain from the removal of the old barrier is an estimated 3,094 feet. 

Why we are removing fish passage barriers

State highways cross streams and rivers in thousands of places in Washington State, which can impede fish migration. WSDOT has worked for nearly three decades to improve fish passage and reconnect streams to help keep our waterways healthy. WSDOT Fish Barrier Correction is a priority.