KINGSTON — Local environmentalists say the Carpenter Creek bridge project is great for the local flora and fauna in the Kingston estuary, but it has had some unintended consequences for the Port of Kingston.
The bridge project, completed in February, opened up Kingfisher and Carpenter streams back to their natural flow into Appletree Cove. Years of sediment buildup, however, has poured out and caused problems for boats at low tide at the boat launch and the ends of B and C docks.
The port is applying for permits to perform a maintenance dredge to remove the extra silt. Port Manager Kori Henry said a dredge is a long time coming — the effect of the opened estuary into Appletree Cove pressured the need for a dredge but did not cause it.
In the last few months, six boats have grounded at low tide, including a few Suquamish fishing boats. Permission to dredge is a difficult process — the port has a meeting with the Army Corps of Engineers, state Department of Fish and Wildlife, Suquamish Tribe and Kitsap County in late July to discuss the port engineer’s hydrographic survey. Preliminary estimates put the cost around $450,000.
Dredging involves excavation of shallow water areas to gather and dispose of sediment accumulated on the bottom, to keep waterways navigable. It is a delicate process, as the excavation that stirs the water can increase turbidity, or cloudiness, which can affect aquatic species’ spawning.
The port first dredged the cove for the boat launch in 1993. Kitsap County took the lead on the bridge project, and the port asked the county to help finance the dredging. However, because the port applied to dredge 10 years ago, Henry said the county is not going to take responsibility for the sediment build up.
The port’s engineer surveyed the current depth and compared that number to the cove’s depth after the initial dredge. To obtain the permits, the report, which is not yet available, will show the various agencies the areas needing to be dredged and to what depth.
The estuary, on the other hand, is thriving. Stillwaters Environmental Center collected data on the water quality and sediment in the creek.
Stillwaters Administrative Director Naomi Maasberg said the mud flats on the north side of the bridge are rich in nutrients.
“There is more fertility per acre than richest farmland in Kansas” in the Carpenter Creek estuary, Maasberg said.
The stream is in a critical position for migrating salmon from river basins throughout Puget Sound, according to Stillwaters’ research, including endangered Puget Sound chinook, chum, coho and sea-run cutthroat trout.
The organization documented the return of a sand dollar colony, and the ghost shrimp that still feed in the 30 acres of salt marsh habitat.
Before, the 10-foot-wide culvert was so narrow it created a water vacuum with the tides.
“The velocity of the water was so strong it was impossible for small fish to get in and out,” Maasberg said. “Before it was like a fire hose shooting in there. Imagine trying to water your garden with a fire hose.”
“It was all a very unnatural situation.”
Now, the streams have “re-meandered” themselves and small critters, plants and insects are returning.
Maasberg said in order to analyze the data they’re collecting, they need more “citizen scientists,” willing to be trained to help process the data.
