Pipe a Winner Right Out of the Gate
The thoroughbreds race at Suffolk Downs in East Boston, Mass., just a mile from Logan Airport. The live horse- racing and simulcasting make it a popular area destination. When management discovered that site drainage work was required, they were certain the construction would have to be completed quickly.
Improvements to the track, which has been in operation since 1935, had to be completed for opening day of the live racing season and simulcast of the Kentucky Derby on May 5, 2007.
The Department of Conservation and Recreation’s Planning and Engineering Division funded and oversaw the contract for the $7 million project, which included Sales Creek culvert replacement, drainage restoration and dredging.
The general contractor, Revoli Construction Co., Inc., North Reading, Mass., and its subcontractors completed the work; Hatch Mott MacDonald was the engineering consultant.
Pipe at center of work
The scope of the work included installation of approximately 2,000 ft of 96-in. diameter centrifugally cast, fiberglass reinforced, polymer mortar (CCFRPM) pipe supplied by HOBAS Pipe USA. The pipe was placed as twin culverts at three different locations around the Suffolk Downs facility in Revere and East Boston. Two of the lines traveled directly under the racetrack surface with the third running under the main entrance road.
Steve Pini, a 36-year employee of Suffolk Downs and superintendent for the racetrack, was pleased with the project outcome.
“The pipe went together well, and was embedded with flowable fill and backfilled with select compacted materials to grade. The surface work and track restoration began after Revoli reached grade,” Pini said.
Phase I included restoring the hydraulic capacity of the drainage system at the two upper-most locations to restore hydraulic capacity and remove blockages.
Phase II included replacing the downstream twin 60-in. diameter HDPE pipe with 96-in. CCFRPM pipe, as well as channel and lagoon dredging.
Pini said, “The 60-in. HDPE pipes were a temporary emergency repair done a few years ago after the collapse of the existing 108-in. corrugated line. The corrosion from the soils and tidal location cut through the corrugated pipe like a razor blade. We knew we would come back with a permanent fix.”
CCFRPM was the only material specified for the storm drainage improvement piping because of its resistance to corrosion, hydraulic capacity and the abrasion resistance. Detailed material specification also included specifics on the interior surface of the CCFRPM pipe, requiring a 50% elongation on the resin used to achieve the necessary abrasion resistance. Proof of prior performance of the pipe product was required. A five-year history and a list of 500,000 ft of installed pipe were required with the submittal package. Because timing was critical, the project specifications included a guaranteed pipe delivery timeframe.
“Work could be performed only in the off-season for the track between Dec. 1 and March 1,” said Shawqi Alsarabi, president of Revoli Construction Co. “March 1, 2006 was the completion date for Phase I, and March 1, 2007 was the completion date for Phase II.”
The tight schedule was caused by the fact that the work involved removing and replacing a building and two sections of Suffolk Downs track.
HOBAS worked with the contractor and designer to provide installation recommendations for the tricky twin-barrel installation submerged in flowable fill by direct bury. The 21-ft trench width allowed for only a 2-ft clear space between pipes and a 1-ft clear space to the trench wall. The native soil material at the 12-ft cover depth had a constrained modulus of only 700 psi.
To combat the properties of the poor native materials and to minimize settlement, a flowable fill was specified for the embedment material.
“We worked in a tight trench to minimize the amount of soil removed and to save on flowable fill,” Alsarabi said. “The 72-psi pipe stiffness provided by HOBAS performed well even in difficult conditions.”
Much of the work on the project was performed in a storm water drainage channel that was subject to storm conditions and fluctuations in water levels. The contractor was required to provide a means to work in the presence of water in the channel, storm events and tidal impacts. Given the geography of the area, installers constantly battled the storm surge.
“We had [an obstacle with] the tide gates during heavy rain and the high tide, which made our bypass ineffective during those events, especially during the second phase,” Alsarabi said. Even given the difficult conditions and quick timing, he added, “The pipe performed well.”
This was his testament to the ease of installation, engineering and customer support provided by HOBAS. “This was the first time Revoli installed HOBAS pipe and the first time we installed this size pipe,” Alsarabi said.
Speaking for Suffolk Downs, Pini said at press time, “With the project completed, we are looking forward to opening day for the 2007 live racing season on May 5.”