A culvert project on Manzanita Creek will better protect spawning.

A family of otters on Bergman Road used to feast on spawning salmon as each fish popped out of a narrow 24-inch culvert.

“It was a deathtrap,” said Robert Tange, across whose property the north fork of Manzanita Creek runs.

One of the finest salmon-bearing streams on Bainbridge Island, the creek was enhanced for fish passage with installation by the city of two new culverts.

“This stream has always had more migrating and resident fish than other creeks on the island,” said Melva Hill, senior engineering technician on the project.

Over the past few weeks, crews have replaced old culverts that allow fish to pass under Bergman and Petersen Hill roads just east of Manzanita Bay at the north end of the island. The old ones, 2 and 3 feet in diameter, were crumbling and the waters were eroding the ground underneath them, both adding silt to the water – bad for fish – and also threatening to collapse the roads above.

The culverts were replaced with large corrugated steel ones 12½ feet in diameter and 8 feet high. The extra width will allow fish to evade would-be predators.

The project cost was $128,154. Hill said proper crossings for streams are required by the state Department of Fisheries when a road is built or renovated.

The Petersen Hill passageway was being laid in last week. It will be lined with creek gravel to allow the water flow to find its own slope.

While the old culvert was angled against the flow of water, the new pipe is corrected to match the natural flow.

In the past, the culvert opening was also situated too high above the creek’s water level, so fish could only gain entrance when waters were running very high.

Still, Tange recalls seeing many fish in the early 1990s when the fish population peaked, with up to 45 pairs in a run.

“Sometimes they sound like trains coming,” he said. “There’d be one swimming up every 30 seconds.”

Members of the Suquamish tribe visit him each year to count salmon.

“The creek is full of baby fry and juveniles,” Tange’s partner Susan Troxell said. “Ninety percent of fish who turn into our stream are coho.”