Crossing a river to place service lines is always challenging.

Contractors seem to have few options, and none of them are easy.

Sheet piles can be driven for excavation to place lines. A cofferdam can be erected to do the work, and in some instances directional drilling can be used to place lines. Sand-bagging, and the use of a K-rail system are also options.

A.A. Roedl Excavating, Inc., Beaver Dam, Wis., has learned those aren't the only options available to contractors to cross a river to place service lines.

The excavating firm was hired to place the water main on a job that placed 3,000 feet of 18-inch sanitary line and another 3,000 feet of 10-inch water lines to provide service to a subdivision being constructed in Beaver Dam.

Roedl Excavating was awarded the underground utility contract for Apple Valley Offsite and Phase I Subdivision. Offsite required 3,000 feet of water and 3,000 feet of sewer to reach phase one development.

Heartland Utilities, Baraboo, Wis., was hired as a subcontractor on the job, and did the sanitary sewer work on the project. Tracy & Sons, Inc., Watertown, Wis., did the televising of the sewer main.

Roedl Excavating did all testing of sewer and water lines.

For the service lines to reach the subdivision, the Beaver Dam River had to be crossed.

Crossing the river, the water main was placed approximately 8 feet beneath the river bed. Although the sanitary sewer was placed an average of about 25 feet deep over most of the project, when crossing the river the sewer main was set 4 feet under the river bed.

Roedl Excavating used the Portadam system to stop the flow of the river so the contractor could excavate beneath the river bed to place the lines.

The Portadam system consists of two main components: a welded tubular steel framework support and a flexible waterproof membrane.

The steel supporting structure with a continuous reinforced vinyl liner membrane provides a means of water diversion, retention or impoundment in a variety of settings.

The support structure is designed to transfer hydraulic loading to a near vertical load, creating a free-standing structure with no back bracing to infringe on the work area.

The liner system is flexible, and seals most irregular contours of the river, lakefront or other water body where the system is used.

The Portadam system can be installed in a variety of configurations and lengths. The equipment is offered as a rental item in heights of 3 feet, 5 feet, 7 feet, 10 feet, and 12 feet.

A 5-foot system was used on the Beaver Dam job.

Supporting structures of different heights can be used on the same job, if necessary, because of stream banks or other irregularities.

Roedl Excavating used the Portadam system to open a work area approximately 50 feet wide and 100 feet in length for the Beaver Dam project.

Pumps cleared water from the work area, and a corrugated metal flume allowed water to pass from one side of the work area to the other.

"We have a 30-inch flume running through, and if the flume can't keep up we can by-pass pump around it," said Fred Bird of Roedl Excavating.

The service lines were placed across the Beaver Dam River in early February.

The city of Beaver Dam assisted in the crossing by reducing the flow of the river during the time the Portadam system was in place. A city-operated dam is located approximately one mile upstream from the site where the river was crossed.

"Normally, the river is running at 48 cfs to 52 cfs (cubic feet per second). The city throttled it back down to about 8 cfs or 9 cfs," Bird said.

Portadam employees spent two days at the job site installing the system.

"Our crew does the in-water portion of the installation, and the contractor provides the support," said Gerry Mann, sales manager for Williamstown, N.J.-based Portadam.

Bird said, "They set up everything in the water. We helped by swinging the A-frames out to them with a crane."

A pair of Portadam divers set up metal A-frames in the river. A fabric membrane installed by the divers covered the A-frames, stopping the flow of the river except for the flume.

"You lay that tarp down in the water, and it goes up and over the stands and you tie it off. Then, you sand bag along the edge of the tarp to seal it off," said Bird.

The Portadam crew also visited the job site before work began to determine the size system that would work best on the project.

"Every job gets a survey before we install it," Mann said.

The Portadam system is easy to install, clean and it contains turbidity at work site.

"It's free-standing; it sits right on the bottom of the river. It's non-intrusive and environmentally friendly," Mann said. "We helped Roedl do the job in a tidy manner and less expensive than probably any other way."

The use of the Portadam system was a first for Roedl Excavating.

"We probably would have had to drive sheeting, if we hadn't used this system. The Portadam system has the least amount of disturbance to the soil. A clay cofferdam would have had too much silt running down river," said Bird.

Sheet piling is commonly used in the placement of service lines beneath a river, but can be costly with the equipment and materials necessary for the work. A crane, vibratory hammer and sheeting are needed.

"If they don't own sheeting, they have to purchase it," said Mann.

In the Beaver Dam job, excavated materials were removed from the river, with clean stone placed as backfill.

After the river had been crossed, the Portadam crew returned to the job site to remove the system, which took one day to complete.

The system was removed prior to a Feb. 15 deadline, which was when Beaver Dam Lake had to be drawn down for the spring thaw.

"The frost helps us out, as far as getting machines through the wetlands," Bird said of winter work in the river's watershed.

The placement of 3,000 feet of sewer lines in what was mainly hard pan began on Jan. 3, and was completed in early March.

Cold winter weather stopped work for several weeks. Placement of water lines didn't start until after the sewer work was well under way.

"We didn't want to be right behind them all the time," said Bird.

Placement of lines was done mainly by digging trenches, shoring and then installing the pipe.

Portadam has been in business for 25 years, and is currently going through a period of rapid expansion. Offices have opened recently in Atlanta and Dallas, Mann said.

A.A. Roedl Excavating, Inc. specializes in residential excavating work, including new home excavation, commercial excavating and underground utility work.

Frank Roedl established the company in rural Beaver Dam in 1906 as F. J. Roedl & Sons. His sons, Edward and Arlea, eventually joined Frank, and operated the family-owned business.

Arlea ran the business for many years with his sons Brian (Pete) and Ronald (Buzz). The two sons took over as partners until Brian retired. Buzz's son Anthony (Tony) Roedl, who had worked alongside his father for several years, took over ownership in 1997, and became the fourth-generation owner.

Under Tony's direction and leadership the company has grown and developed from mainly residential work to larger commercial projects and underground utility work.

"For the longest time our main business was basements and grading. Since Tony took over, he's been getting into sewer and water," said Buzz Roedl.

And as Roedl Excavating approaches its 100th anniversary, the type of work the company does continues to increase.