Unexpected Obstacles Resolved With Rental & Piling Equipment
Barnard Construction Co. Overcomes Water, Cap Rock, While Building Storm Drainage System for Lubbock, Texas
Water, water, everywhere. That was the biggest challenge in building a new storm drainage system for Lubbock, Texas, according to Mike Jones, general superintendent on the $30 million project.
Jones' company, Barnard Construction Co. of Bozeman, Montana, built about 20 intake and outflow structures in several "playas," or lakes, which serve as natural stormwater retention basins throughout southern Lubbock. The company installed piping to connect the playas, facilitating the flow of excess water during storms and reducing surface flooding.
Before each intake and outtake structure could be built, a temporary sheet pile cofferdam was erected to ensure worker safety and to increase efficiency. "We have to put in the shoring in case of rain," Jones explained. "We're working in zero to 19 feet of water for the shoring system," he said. "Some of the playas are dry, but then we'll get some rain and the water comes up." In mid-November 2001, Lubbock received about three inches of rain in 48 hours, and the lakes rose as much as 8 feet.
The crews had to build causeways and access pads so they could get the cranes close enough to put in the sheet piling. "Our big problem was access - getting close enough to reach out into the water," Jones commented.
The soil conditions were good - a sandy lean clay - however, work crews unexpectedly ran into cap rock at about 25 feet, causing a change of plans. "You can only pound down pile so far with that cap rock," Jones said. The flexibility of Hammer & Steel - which provided the sheet piling and equipment for this project - helped Jones make the adjustments required to keep the project running smoothly.
Originally Barnard Construction ordered a combination of 40' and 25' long Hoesch steel sheet piling from Hammer & Steel, which handled the rental of 400 tons of piling. But once the cap rock was discovered, Jones realized he would need significantly more 25-foot pieces. "Hammer & Steel has been super to work with," Jones commented. "They did a good job of getting us what we needed as soon as possible."
Barnard had also rented an HPSI 500 vibratory driver/extractor for the job. With the switch to shorter sheets, however, Jones decided to switch to a lighter model. Again, Hammer & Steel was very accommodating in getting the requested machinery to Lubbock.
Jones' crew used Dawson sheet pile threaders and ground release shackles to interlock the sheets, and the superintendent said he was very impressed by them. "This was the first time my crew used the Dawson threaders. They work much better than others we've tried." Barnard Construction uses the threaders because the safety of its employees is a key concern, but the threaders have also increased productivity in windy conditions. "The wind hasn't slowed us down," Jones said. "We've used the threaders in gusts up to 20 or 25 mph, and using the threaders has definitely helped us there."
Equally impressed by the performance of Hammer & Steel, Jones said, "It's been great working with Doug Picker," who handled the project out of Houston for Hammer & Steel. "He's done a good job getting us anything we requested: spare fittings and hoses for the hydraulic unit; finding us used Dawson threaders to buy. All the piling has been in good shape - it all looks new. And the deliveries have been here when we needed them."
For Picker, making sure the deliveries were on time has been a real point of pride. Lubbock is more than a 10-hour drive from Houston and 20 hours from St. Louis, two of Hammer & Steel's stocking locations. "We have good relationships with several trucking companies, which helped a lot, but since Lubbock is somewhat remote, they weren't always willing to make deliveries without charging an arm and a leg," Picker noted. Early in the project, Picker developed a relationship with a trucking company based in Lubbock, which has provided "good availability and decent rates in getting there," he said.