POULSBO — That the culvert needs to allow fish passage was apparent once Public Works employees unclogged the crossing under 8th Avenue at Lincoln Road during a rainstorm Nov. 19.

As Public Works employees watched, a female salmon swam by and laid her eggs in a redd. A male salmon followed and deposited milt over the eggs.

The south fork of Dogfish Creek flows here from its headwaters in Wilderness Park a mile away. From 8th and Lincoln, it meanders through some private yards to Centennial Park, through Poulsbo Village to Bond Road, where it connects with the mainstem of the creek and flows to Liberty Bay. Biologists have documented the spawning of coho and cutthroat trout on the south fork.

The state Department of Fish and Wildlife developed culvert design guidelines to ensure culverts don’t restrict fish passage — that is, keep salmon and other fish from going to and from spawning and rearing habitat. Other agencies involved in developing the guidelines: state Department of Transportation, the state Department of Ecology, the U.S. Army Corps of Engineers and the U.S. Fish and Wildlife Service.

The culvert that crosses under 8th Avenue at Lincoln does not meet those standards, according to a state habitat biologist and a 2010 study commissioned by the city. And because it is constricting stream flow, sediment is filling up an upstream culvert that passes under Lincoln Road.

“This culvert does not meet Fish and Wildlife standards,” emailed Gina Piazza, area habitat biologist for the state Department of Fish and Wildlife. “I attribute most of the problem with the upstream culvert to be due to the constriction downstream” at 8th and Lincoln.

“The downstream culvert is impounding water and sediment which results in sediment dropping out upstream and filling up the upstream culvert. The undersized pipe downstream is not allowing all the sediment, water, and woody material to convey naturally downstream as it should. The upstream pipe will need to monitored and potentially maintained until the downstream pipe is replaced.”

According to the 2010 study, the culvert is the only culvert on the south fork identified as a potential barrier to fish passage.

“The culvert is a round precast concrete culvert measuring 30 inches in diameter. Every other culvert inventoried within the fish-bearing reaches of the stream was eight feet in diameter or larger and countersunk a minimum of 20 percent, and had gravel substrate through the culvert creating a natural bed that assists fish migration.” 

Besides restricting fish passage, blocked culverts can cause streams to overflow their banks and to wash out roads. A culvert on the 21000 block of Bond Road, outside the city limits, washed out in a storm in December, taking a section of access road with it and leaving a 20-foot-deep chasm between a small rural neighborhood and Bond Road. The previous month, a blocked culvert washed out on Storhoff Road, washing out a driveway.

Public Works crews have to clear the culvert at 8th and Lincoln “once a year maybe,” Poulsbo Public Works Director Barry Loveless said. “It has flow, but it’s severely restricted. If it doesn’t [have flow], it overflows the road.”

Loveless said the 8th Avenue culvert is too small and the city would like to replace it with a small bridge or a box culvert. He said it’s one of two undersized culverts owned by the city. The other is near Noll and Storhoff roads; that culvert will be replaced when the city builds a connector road, he said.

Replacing the culvert at 8th and Lincoln would be more challenging: In replacing the culvert, Public Works would need to do some creek bed restoration downstream, but that portion of creek is on private property, Loveless said.

“Ideally, we’d like to get that property and fix the creek bed, but it’s not for sale,” he said.

While Loveless admits the culvert is too small, he said rocks placed by Fish and Wildlife upstream are mostly responsible for filling the culvert under Lincoln Road.

Loveless said the culvert that passes under State Route 305 was once half full with rock. “If you have a 10-foot culvert and you fill it 5 feet with rock, the rock’s going to go somewhere,” Loveless said. “That’s mostly what’s plugging the culvert” under Lincoln Road.

The city is not affected by a U.S. District Court judge’s ruling requiring the replacement of culverts under state-owned roads, but the ruling shows how seriously the feds take the plight of endangered and threatened salmon. A 2012 study by the Northwest Indian Fisheries Commission determined that the Salish Sea is losing salmon habitat faster than it can be restored, and counted fish-blocking culverts as one of the problems.

On March 29, U.S. District Court Judge Ricardo Martinez ruled the state must fix culverts under state-owned roads if those culverts block fish passage, because they violate Tribal treaty rights. Martinez gave the state 17 years to “[correct] the barrier culverts.”

Indigenous leaders signed treaties with the U.S. government more than 150 years ago that reserved for their people and their descendants the right to harvest salmon. That right was upheld in U.S. v. Washington, the 1974 ruling that recognized Tribes’ right to half of the harvestable salmon returning to state waters. The ruling established Tribes as co-managers of the resource with the state.

The March 29 order was necessary, Martinez ruled, because the state had reduced repair efforts in the past three years, resulting in a net increase of culverts that block fish from habitat. At the current rate, repairs would never be completed, he ruled, because more culverts were becoming barriers to salmon than were being fixed.

Lars Erickson, spokesman for the state Department of Transportation, said in an earlier interview, the ruling could affect 817 culverts statewide, 73 of them in Kitsap County.

He said he didn’t know if all state culverts in Kitsap County would need to be replaced.

He said culvert replacement would cost about $1.9 billion, “but those are 2012 numbers that don’t account for inflation, don’t account for additional failing culverts that haven’t been identified yet, don’t include the cost to correct barriers outside the case area, or the capacity for resource agencies to support our work.”

Dr. Chris May, director of Kitsap County’s surface and stormwater management program, said in an earlier interview that the county has been working on replacing fish-blocking culverts since the mid-1990s, averaging two or three culverts a year. The county has identified approximately 40 culverts that must be replaced. Culverts are scheduled to be replaced this year and next year on Chico Creek, Clear Creek, Dickerson Creek and Seabeck Creek.

He said replacing a culvert — design, permitting, construction — can cost more than $500,000.

“The list never goes away,” he said. “As we replace culverts, we sometimes find others.”

Photos, from top: 1. The south fork of Dogfish Creek crosses Highway 305 through a box culvert. 2. It crosses Lincoln Road through an arch culvert. 3. Rock and sediment are  narrowing the passage on the other end of the arch culvert. 4. The south fork of Dogfish Creek passes through this small culvert under 8th Avenue en route to Centennial Park, Poulsbo Village and then Bond Road, where it connects with the mainstem of the creek and flows to Liberty Bay. Richard Walker / Herald