Working in Tight Spaces

By Joanne Ray | September 28, 2010

“The tightening economy forced us to look further away for work,” said Northeast employee Sue Tiede. “Our dedicated crew members made the long drive to and from Conway each day and put in a great effort to complete a couple of difficult jobs before winter closed in.”

And difficult the job was.

The $725,000 project broke ground in July 2008 with a completion date of spring 2009.

With five to 14 laborers on the job each day, along with three backhoes, one loader, one roller and one dozer, the crew began installing a neighborhood sewer pump station. Right away crew members had their work cut out for them because they had a very small area in which to work.

“This was a very difficult job because of the amount of water we had to fight to get the stuff into the ground,” said Rodney Stockman, project manager for Northeast Earth Mechanics. “It took a lot more time than expected. We expected a little bit of water but there was much more than we anticipated.”

Stockman said the project included installing new town sewer and water and sewer upgrades – involving a new pump station at the end of Depot Road in North Conway. Part of the project also involved Neighbors' Row, which was all gravity sewer and therefore did not need a pump station.

“Each house on Depot Road will drain into the pump station and then pump out to the treatment plant,” Stockman said.

Stockman said Northeast's job was to furnish all labor, materials, equipment, and incidentals required to construct the infrastructure improvements and all other related work in its entirety as specified.

The scope of work included: one wastewater package pump station; approximately 1,325 linear feet of 8-inch PVC gravity sewer pipe, including manholes, services and other appurtenances; approximately 1,025 linear feet of 8-inch DI water main, including valves, hydrants and service connections; approximately 800 linear feet of 4-inch PVC forcemain – including bends and fittings; full width initial paving on Neighbor's Row and temporary trench width paving on Depot Road; loaming and seeding where required; clearing and restoration of the sewer easement area; and obtaining and complying with the conditions of all necessary permits required for the project, including a NPDES Construction Dewatering Permit and a town of Conway construction permit.

One of the first tasks was to get the shoring in place with the help of Al Randall from Northeast, who operated a CAT 345 during the entire process.

“There wasn't much room to open the hole, so we went with the slide rail system – a 16-foot by 16-foot square box – and put it around the perimeter of the hole,” Stockman said.

The slide rail shoring included eight 8-foot by 16-foot panels; four 4-foot by 16-foot panels, and four 20-foot corner posts.

“We basically had no place to put the excavator,” said Kenny Scribner from N.E. Positioning systems, who supplied the slide rail materials. “The excavator could only sit on one side and had to do the whole job by reaching across the trench to install the panels. They built a ramp so the excavator could move up and down. It was tough because there was water everywhere. It was like an orchestra trying to get everything to go together.”

Scribner pointed out that the pump station had to be 28 feet deep.

“So in order to do that, what we did was cut 8 feet off the top before we even started,” Scribner said. “Then we put in 20 feet of slide rail panel. We used two 8-foot panels and then stuck a 4-foot panel on top. So we had 20-feet of total height for the slide panel.”

Stockman said the pump station was very wet, so in order to deal with the water problem the crew put together a well-point system around the hole.

“It operated 24 hours a day, and that is how we drained the water down,” Stockman said.

Stockman said the drainage pump system had approximately 500 feet of 8-inch header pipe and 30 to 40 well points varying in length from 5 feet to 24 feet.

“It works off of a vacuum and hooks up to a pipe hose and ties into 8 inches of pipe,” Stockman said.

When the hole was ready, a 6-foot-diameter concrete sewerage pump station from Phoenix Precast in Concord, NH, was installed.

In November, the crew was doing finish work and trying to meet the month's paving goals. Northeast contracted R&D Paving from Pike Industries to pave 750 feet of road that will be 22 feet wide.

“We are going to put on a 2-inch wearing course, and the town will put 1 inch more on later,” Stockman said.