Vermeer Tackles Difficult Trenching Where Mountains Meet Desert in NV

Sat July 24, 2004 - West Edition
April Goodwin

It’s tough to imagine a time and a place for a 90-ton, 600-hp (80 t, 447 kW) trencher. But Dave Rice, owner of Las Vegas-based Rice Construction Co. Inc., isn’t gambling with anything less.

Rice replaced a trencher that weighed approximately 60 tons (54 t) and 400 hp (298 kW) and has increased production by approximately five times. It takes that much of a monster machine to get through the brutal rock of the Las Vegas valley, he said.

Las Vegas has a reputation for many things, but one thing it’s definitely notorious for (in the construction world) is hard rock. Trenching and excavating in the area have always ranged from difficult to impossible. Now, thanks to explosive growth in the area, it’s even harder.

Rice has been in business in Las Vegas since 1989 and has watched the city fill the valley and reach mountains on three of four sides as the city’s population has more than doubled. While the boom is great for business, the downside for contractors like him, who install utilities for new developments, is they must deal not only with normally brutal underground desert conditions, but with mountainous rock, too.

His crew is currently installing 10-in. (25.4 cm) water main about 13 ft. (4 m) deep as part of a 623-acre (252 ha) development called the Canyons at McDonald Ranch, being developed south of Las Vegas by the McDonald Companies.

The development will bring 990 single- and multi-family homes to south Henderson, near Green Valley Parkway and Horizon Ridge Parkway.

Rice recently purchased a Vermeer T1255 Commander, the largest production track trencher available from the manufacturer, to help tackle the project. He said they couldn’t have done the job without a machine that size.

“We’re seeing a lot of stone along with caliche,” he said. “Our last trencher got 30 to 40 feet per day.” Now, he’s getting 300 to 400 ft. (91 to 122 m) per day and, according to Rice, expects improved results when he moves the machine to an area filled with only caliche on the next job — a Summerlin project west of the city.

The company also uses a large excavator on the project, used primarily to dig boulders and loose rubble out of the bottom of the trench as well as to “bench” the top couple of feet to keep it from caving.

Benching is a common method of excavating the sides of a trench in a series of horizontal levels or steps used either to trench deeper than the machine’s boom reaches or prevent caving. Although it’s been necessary on past jobs to do full benching, it wasn’t needed on this shallow, 13-ft. (4 m) job. In fact, he didn’t even need the complete boom.

The “rubble” Rice describes others recognize as “boulders.” He said it’s not uncommon in the area to come across something a few feet in diameter that the excavator must pull out.

The T1255 is equipped with the Vermeer trencher electronic control (TEC) system, which automatically adjusts the trencher to varying conditions and adjusts track speed, in addition to monitoring trenching operations and displaying useful data.

The job on Horizon Ridge is a minor one compared to some others Rice has recently worked on. He just finished putting in 18-in. (45.7 cm) storm drain — a job where the Vermeer T955 trencher had to make two passes and they had to bench to get the boom 14 ft. (4.3 m) deep in the 3-ft. (.9 m) wide trench.

Now, he said he won’t need to make two passes on a job again with the T1255. “But if I didn’t have a machine this size on this job, that’s what I’d have to be doing,” he said.

Rice Construction has 45 employees who work across half-a-dozen crews. Their work is primarily water and sewer, but contract to do dry utilities as well. In addition to the T1255, the company owns a Vermeer T955 and T855. “The bigger trenchers do the wet stuff,” he said.

Rice prefers trenching to blasting or using a ball drop, which “doesn’t leave you a product you can reuse,” he said. Trenching, on the other hand, produces rock smaller than 1-in. in diameter that can be used to fill ditches.

Rice is quick to point out that he’s not the only one at Rice Construction who likes the big trencher. “So do my operators,” he said, “and if you’ve got operators like mine, you give them what they want.”

So what does Rice think the future holds for trenchers? “You need a big, strong trencher in ground conditions like this … In other parts of the country, they have granite and limestone — some of the toughest stuff around. But you get into solid rock and caliche down here, and you need the biggest, strongest machine money can buy.”

(April Goodwin is a technical writer from Des Moines, IA)