This summer, a horizontal drill will bore a hole 10 feet below the bed of the Wishkah River, making way for an eight-inch-wide pipeline to carry natural gas to customers.
Cascade Natural Gas Corporation’s Wishkah Road Pipeline Reinforcement project will increase the company’s capacity to meet demands in Aberdeen, primarily for industrial growth, according to spokesperson Mark Hanson.
The company will install 1.7 miles of new high-pressure natural gas pipeline underneath Wishkah Road and East Wishkah Road, while crossing underneath the river about three miles north of its mouth.
The Grays Harbor County Planning Commission granted permits for the project at a Tuesday meeting, with construction set to begin in late summer and last three months or less.
The county’s Shoreline Master Program, which regulates development on shorelines and riverbanks, requires the pipeline to be placed at least 10 feet below the bed of the Wishkah River.
Clint Mathews, district manager for CNGC, said that distance is enough to prevent the ground underneath the river from cracking during horizontal drilling, producing a leak. He said river crossings during pipeline expansions are common practice.
“There is no impact to the river by this drill,” he said.
Contractors will use a bore pit aside the river to access underneath the bed. From there, an operator at the surface will control drill movements using information relayed from a signal at the head of the drill.
On Tuesday, Planning Commissioner Bruce Daniels asked representatives of the company how they would be able to tell that the drill was maintaining a 10-foot buffer.
“Technology has improved in terms of bathymetric survey,” said Vince Barthels, an environmental consultant with engineering firm Ardurra. Bathymetry is the study of underwater topography. “Depending on the tide, they can get out there and measure the bottom. You’d be surprised, these boring devices, you can tell how deep it is.”
While the pipe won’t touch the Wishkah River, the project will disturb about 3,000 square feet of wetlands on the east side of the river, according to the permit application. To offset impacts to wetlands, the company plans to purchase $169,950 of wetland credits through the state Department of Ecology. That money will be contributed to the Chehalis Basin Mitigation Bank, a 177-acre restoration site along Hanaford Creek in Lewis County, which was degraded by heavy industry.
The bulk of the new pipeline will lie in the rights-of-way of Wishkah and East Wishkah roads. The company also has several easements on private property.
Boring will begin and end at 2852 Wishkah Road and 141 E Wishkah Road. When one homeowner expressed concern about access to homes in the area during construction, Barthels said parts of each of the roads would likely be blocked off in chunks at a time.
“Generally they try to narrow it down to at least one lane,” he said. “They’ll come up with a detour plan and accommodate all the residents.”
Mathews said the project will connect to another reinforcement the company finished a few years ago. According to permit applications, the estimated value of the project is $3.5 million to $4.5 million.
Contact reporter Clayton Franke at 406-552-3917 or clayton.franke@thedailyworld.com.