Oct. 23, 2014
THE DALLES, Ore. — Sustainability and frugality have been key themes throughout construction of the Port of The Dalles’ newest industrial subdivision, which is nearing completion.
Project Engineer Ken Valentine of the Harper Houf Peterson Righellis Inc. engineering firm of Vancouver, Wash., provided an update on the project Oct. 22 for the port commission.
When completed, the 60-acre industrial park will feature 26 riverside, shovel-ready building lots of 1 to 4 acres at the eastern end of the Columbia River Gorge with paved roads and utilities — including high-speed internet — stubbed to each site.
A bioswale storm water filtration system on each side of the roadway is one of the sustainable features. Bioswales are landscape elements designed to filter and remove silt and pollution from runoff water. They involve a shallow, winding trough with gently sloped sides designed to maximize the time water spends in the swale, which aids in trapping pollutants.
“It’s a more green method of disposing of storm water,” Valentine said.
The water will be treated as it comes off the site by being diverted through the bioswales.
“The bioswale acts as filtration,” Valentine said. “The parking lots are graded so that almost all of them slope toward the swales as well.”
Bioswales are used more commonly in the Willamette Valley, but are relatively rare in the Columbia Gorge.
“They will be really pretty once everything is landscaped,” he added.
The design will also include curb cuts that allow water to more easily flow from roadways into the swale areas.
Another sustainable and economical part of the construction process is the reuse of much of the rock and wood chips removed during site preparation.
The volume of rock and wood chips that would have to be removed from the site was largely unknown going into the project in the early spring, Valentine said. Both came in at more that original estimates.
The pockets of wood chips, remnants from the site’s days as a chip mill, have been allowed to biodegrade in a large heap over the summer and are being sifted for use as high-quality topsoil on the site.
Much of the 12,000 to 13,000 cubic yards of rock blasted to level the site and prepare utilities trenches is also being reused on site.
“We haven’t wasted anything out there,” Valentine said.
Testing on the project’s sanitary sewer lines has already begun, he said. The 18-inc