KINGSTON — A project that began 13 years ago is expected to be completed in 2017.
The culvert under West Kingston Road will be removed. It will improve the flow of water within the Carpenter Creek estuary. It is the second of two culverts identified in 2001 that members of Stillwaters Environmental Center wanted to see replaced.
“It will be a huge enhancement … allowing the free exchange of salt and fresh water,” Kitsap County Public Works Director Jon Brand said.
The work is being done by the county and funded completely by the U.S. Navy. The Kitsap County Commissioners approved the contract with the Navy on Sept. 8; the Navy earmarked $2,972,130 for the project. County officials met on Oct. 6 with the consultant who will design the bridge, Brand said.
A call for construction bids won’t go out until early 2017, Brand said.
The culvert and section of roadway that will be replaced are located near the bottom of the hill of West Kingston Road, not far from Siyaya Avenue. The bridge will have a 150-foot span and will replace the 5-foot-wide culvert. The bridge will have two spans.
Construction is expected to start in summer 2017. A portion of West Kingston Road will be closed during construction, Brand said. The reason for a complete closure is because of the expense of allowing through traffic during construction, Brand said.
The culvert on West Kingston Road follows the replacement of a culvert on South Kingston Road in 2012. The 90-foot single-span bridge helped restore more natural tidal flow between the 30-acre estuary and Apple Tree Cove.
During the construction of the bridge on South Kingston Road, traffic remained open. It cost $700,000 to keep the road open during construction, Brand said. A temporary bypass was constructed so traffic could make it over the waterway.
“The cost of keeping the road open [during construction] is really expensive,” Brand said.
The culvert project was not the first on the list for mitigation work in the county. A lagoon in Keyport was originally the next mitigation site, but high levels of contaminants in the lagoon stopped the project, according to Suquamish Tribe ecologist Steve Todd.
The culvert replacement is part of a $9 million agreement between the Navy and Tribes in the Hood Canal region for mitigation projects that affect fish and shellfish, following the announcement in 2012 that a second explosives-handling wharf would be built at Bangor.
“There’s been interest in opening that up for many years,” Todd said of the West Kingston Road culvert. “It provided a good fit [with the agreement between the Tribes and Navy.]”
The removal of the culvert could result in some significant changes in the estuary. The culvert was “almost a partial dam” between the Carpenter Creek and the estuary, Todd said. The small culvert resulted in trapped sediment. With the culvert removed, there will be added tidal movement.
The estuary is frequented by fish transferring from streams to the ocean and used by migrating fish coming from the southern Puget Sound region. Juvenile salmon, steelhead and chinook feed in the estuary.
Changes in vegetation could be seen as well. Currently, there is more freshwater marsh vegetation in the upper portion of the estuary, Todd said. There may be a change to more saltwater vegetation in the future, with the estuary returning to salt marsh, he said.
Because of a lack of tidal exchange and increase in water runoff, the estuary has become more freshwater, said Naomi Maasberg, administrative director of Stillwaters Environmental Center. That has resulted in more freshwater vegetation. Under more natural conditions, the estuary would be more of a mix of salt and fresh water — brackish.
Todd said the habitat will be monitored over a period of years to see what specific changes happen. Stillwaters Environmental Center has monitored changes since the first culvert was removed.
Though the South Kingston Road culvert was first to be replaced, Maasberg said it was the West Kingston Road culvert that started it all. That is because West Kingston Road was considered for widening at the time, without much change to the culvert, she said. Back in the early 2000s, however, there wasn’t enough money to remove the culvert.
It is a long time in the making, Maasberg said.
“It will be so awesome,” she said of the culvert removal. “So excited just to watch.”
