The Way I See It!

Deep Tunnel History Part 1

Posted by Randy Hollenbeck on Aug. 9, 2010

MMSD

No end to the tunnel

Milwaukee Journal, The, Feb 14, 1995 by KARL EBERT

When the Milwaukee Metropolitan Sewerage District began planning construction of the deep tunnel in the late 1970s, Joseph P. Sehulster decided that his future lay in the vast, multimillion-dollar public works projects that loomed on the horizon.

But the owners of the concrete pipe company he managed at the time had no interest in positioning themselves to bid on the deep tunnel projects.  In 1980, Sehulster decided it was time to form his own company.

That year, Sehulster Tunnels Inc. won the first of a series of contracts to manufacture tunnel linings for MMSD projects.  Tunnel linings are the concrete pipes that actually form the shape of the tunnel.

Sehulster subsequently worked on four other sections of the tunnel system, building a base of experience that has earned the company big contracts across North America and an international reputation.

"Milwaukee was the first project of its kind, and they had the foresight to consider and specify the latest technology," Sehulster said.

"People from all over the world came here to see those tunnels, and that was the launching pad for us in North America.  Now our technology goes all over the world from right here in Milwaukee."

Most recently, Sehulster was awarded a $6 million contract to manufacture liners for a 10,000- foot tunnel for the Seattle sewer system.

With a core staff of just five people, including Sehulster's wife and company president, Carmen Sehulster, and his son Tom, the company has to start up an entirely new production operation every time a contract is awarded.

Sehulster relies on a network of Wisconsin engineers, contractors and manufacturers, all of whom worked on the deep tunnel, to give him the flexibility to survive the lean times.  The businesses give the company access to engineers and other specialists without having to carry them on the payroll year round.

"There are tremendous manufacturing resources in Milwaukee, but you need someone like Joe who can get the jobs and put it all together," said George Forish, vice president of longtime Sehul-ster collaborator Precision Pattern Company Inc.

Precision Pattern is helping the company prepare the molds that will be used to create tunnel segments for the Seattle project.  Unlike previous projects, which required construction of new molds, Sehulster will be able to re-use molds left over from construction of Milwaukee's deep tunnel.

The fabrication of molds always begins at a leased factory in Milwaukee.  Because Sehulster does not need a factory year round, the fabrication site changes for almost every project.  The current operation is on Ward St. on the near South Side.

Once the molds for the current project have been refurbished, they will be shipped to Seattle, where a second plant will be leased for the actual manufacture of the tunnel segments.  Sehulster said that part of the operation would require as many as 30 full-time employees when manufacturing begins in August.

Tunnel construction is a cyclical business in which a company can be idle for as long as eight months between projects, Sehulster said.  He declined to disclose the company's annual revenues.

In recent years, Sehulster Tunnels has produced tunnel linings for a number of large sewer and transportation projects, including a $30 million contract for a 9.5-mile-long, 24-foot-wide sewer outfall for Boston, and a $15 million contract to co-manage lining of a 27-foot-wide railroad tunnel under the St. Clair River, 50 miles north of Detroit.

Sehulster says his company did well from the start, but he points to 1987 as a watershed year.  That year, MMSD specified the "single pass" tunneling technique for a difficult 10,000- foot stretch through gravel and silt under the Menominee River.

Single pass tunneling simultaneously bores the tunnel and lines it with precast concrete liner segments.  It had been developed in Europe and Japan as a safe and fast alternative to traditional tunneling methods in wet and unstable soil.  Traditional methods use compressed air to hold loose earth in place until a superstructure can be erected.

The technique was not widely used in the United States before 1987, but it quickly became Sehulster's bread and butter.

Sehulster engineers developed special liner sections with watertight rubber gaskets for that project, and introduced a "fast lock" system of connecting dowels and mechanical joints for easy assembly in tight underground work areas.

Sehulster subsequently patented the company's fast lock technology and licenses it to foreign tunneling firms, including British giant Charcon Tunnels Ltd., one of the contractors on the English Channel tunnel.

Sehulster says his company is the only full-time supplier of segmented one-pass tunnel linings in the US.

Ross Webb, an estimator for McNally Tunnels Corp., the general contractor for the Seattle project, agrees that Sehulster is unique in the industry.

"Most segmented jobs go to Sehulster because his is more of a full-service company and he's got more experience than the others," Webb said.

With a core staff of just five people, including Sehulster's wife and company president, Carmen Sehulster, and his son Tom, the company has to start up an entirely new production operation every time a contract is awarded.

Sehulster relies on a network of Wisconsin engineers, contractors and manufacturers, all of whom worked on the deep tunnel, to give him the flexibility to survive the lean times.  The businesses give the company access to engineers and other specialists without having to carry them on the payroll year round.

"There are tremendous manufacturing resources in Milwaukee, but you need someone like Joe who can get the jobs and put it all together," said George Forish, vice president of longtime Sehul-ster collaborator Precision Pattern Company Inc.

Precision Pattern is helping the company prepare the molds that will be used to create tunnel segments for the Seattle project.  Unlike previous projects, which required construction of new molds, Sehulster will be able to re-use molds left over from construction of Milwaukee's deep tunnel.

The fabrication of molds always begins at a leased factory in Milwaukee.  Because Sehulster does not need a factory year round, the fabrication site changes for almost every project.  The current operation is on Ward St. on the near South Side.

Once the molds for the current project have been refurbished, they will be shipped to Seattle, where a second plant will be leased for the actual manufacture of the tunnel segments.  Sehulster said that part of the operation would require as many as 30 full-time employees when manufacturing begins in August.

Tunnel construction is a cyclical business in which a company can be idle for as long as eight months between projects, Sehulster said.  He declined to disclose the company's annual revenues.

In recent years, Sehulster Tunnels has produced tunnel linings for a number of large sewer and transportation projects, including a $30 million contract for a 9.5-mile-long, 24-foot-wide sewer outfall for Boston, and a $15 million contract to co-manage lining of a 27-foot-wide railroad tunnel under the St. Clair River, 50 miles north of Detroit.

Sehulster says his company did well from the start, but he points to 1987 as a watershed year. That year, MMSD specified the "single pass" tunneling technique for a difficult 10,000- foot stretch through gravel and silt under the Menominee River.

Single pass tunneling simultaneously bores the tunnel and lines it with precast concrete liner segments. It had been developed in Europe and Japan as a safe and fast alternative to traditional tunneling methods in wet and unstable soil. Traditional methods use compressed air to hold loose earth in place until a superstructure can be erected.

The technique was not widely used in the United States before 1987, but it quickly became Sehulster's bread and butter.

Sehulster engineers developed special liner sections with watertight rubber gaskets for that project, and introduced a "fast lock" system of connecting dowels and mechanical joints for easy assembly in tight underground work areas.

Sehulster subsequently patented the company's fast lock technology and licenses it to foreign tunneling firms, including British giant Charcon Tunnels Ltd., one of the contractors on the English Channel tunnel.

Sehulster says his company is the only full-time supplier of segmented one-pass tunnel linings in the US.

Ross Webb, an estimator for McNally Tunnels Corp., the general contractor for the Seattle project, agrees that Sehulster is unique in the industry.

"Most segmented jobs go to Sehulster because his is more of a full-service company and he's got more experience than the others," Webb said.

Source: MJS