Crews replacing power grid beneath Saginaw River

$5 million electrical overhaul is in preparation for large industrial park development

By Justin Engel
MLive.com

BAY CITY, Mich. (AP) — Subterranean surgery is under way deep beneath the Saginaw River floor.

As motorists move between Bay City’s east and west sides, driving across the community bridges as they have for decades, a Consumers Energy-contracted crew is drilling 50 feet beneath the riverbed in an effort to replace a 59-year-old power grid.

The $5 million electrical overhaul is in preparation for the 43-acre Uptown Bay City project, which is expected to land about 500 jobs in downtown Bay City by 2014.

To make way for construction at the site, Consumers Energy is replacing two 188-foot-tall power lines on both sides of the river with a pipeline designed to carry that energy instead beneath the river.

That wing of the project began days before Thanksgiving, Consumers Energy Senior Engineer Louis Hincka said, when crews turned a Veterans Memorial Park baseball diamond parking lot into the insertion point for a state-of-the-art drill designed to clear a path for a 1,100-foot-long tunnel.

“It’s a once-in-a-career project,” said Hincka, a 13-year Consumers Energy employee.

Hincka is in charge of the project’s engineering while Consumers Energy-hired Gabe’s Construction, out of Sheboygan, Wis., is tasked with the dirty work.

And it does get dirty.

While crews finished creating a reverse rainbow-shaped path beneath the river two days after the drilling began, Hincka said several steps remain before workers can insert the tunnel, which is set up and waiting on the river’s west side.

“It’s a dance,” he said of the process behind the drilling.

The waltz begins on the river’s east side, where Gabe’s workers set up the drill base and project headquarters — which resembles a hot dog stand from the outside and something closer to a Michael Crichton novel on the inside — in the middle of the park’s baseball field property.

Inside the hot dog stand is a computer setup that provides workers a three-dimensional “world” mapping Bay City’s subterranean layers, and shows crews where they’ve pinned a hole through it, Hincka said. Project leaders use the technology to ensure the drill doesn’t veer off course or poke a hole into the river itself.

The drill base is set up on a diagonally-turned semi-truck trailer bed, which sends the metallic drill at an angle into the earth.

A cavity the size of a vehicle marks the entry point, and a substance resembling a frozen mix of water and mud fills much of the gap.

Despite the cold temperatures, that’s not icy river residue, though, Hincka said.

The substance is actually industrial-grade clay. The gunk is sprayed — along with water — from the serrated drill head as it chomps through the soil.

The effect coats the outer walls of the hole, ensuring its integrity against the unpredictable nature of the underworld.

On the west side of the river, things aren’t quite as high-tech. There, the drill head pokes through a breach within the Uptown Bay City property, and workers replace it with a new head before sending the drill back in for another pass through the opening.

Crews will continue to develop the hole for at least another week, Hincka said.

That’s ahead of schedule for planners who didn’t anticipate the soft nature of Bay City’s sub-riverbed soil.

“The conditions were better than expected,” Hincka said. “There was a lot more silty clay than gravely rock.”

The result allowed Gabe’s Construction to run some of its equipment at half-power, meaning a less noisy Bay City riverside near the site.

While it took only two days to create the first 8-inch-wide “pilot” hole, workers continue to expand it in preparation for the tunnel, he said. After a second, 30-inch-wide hole was drilled, crews on Thursday began the next expansion to 42 inches.

The final, 48-inch-wide drilling likely will conclude next week, Hincka said.

The 32-inch-wide tunnel — made up of a plastic known as high-density polyethylene, or HDPE to industry types — will be snaked through the hole and in place by about Christmas, he said.

Lighting up the power lines that the tunnel will host could take months more, officials say. No timetable is set publicly.

Once the grid is tested and established, work will begin on deconstructing the 188-foot-tall towers that have carried power from one side of the river to the other since 1953.
The Uptown Bay City site — owned by Samuel Shaheen and his company, SSP Associates — in two years will host Great Lakes Bay companies including Dow Corning, McLaren Bay Region and Chemical Bank.