Jan. 12, 2004 -- If Buddy Holly helped put Lubbock on the map, heavy rains and flooding have done their best to take it off. So, when a warning like the one quoted below is published, this major city located in the Texas panhandle takes it very seriously.
NATIONAL WEATHER SERVICE LUBBOCK TX
603 AM CDT THU JUN 26 2003
THE NATIONAL WEATHER SERVICE HAS ISSUED AN URBAN AND SMALL STREAM
FLOOD ADVISORY FOR...LUBBOCK COUNTY IN NORTHWEST TEXAS UNTIL 800 AM CDT
EXCESSIVE RUNOFF FROM THIS STORM WILL CAUSE FLASH FLOODING OF SMALL
CREEKS AND STREAMS...HIGHWAYS AND UNDERPASSES. STREET FLOODING WILL
BE WIDESPREAD.
In an extremely flat area that was a lakebed some 150 million years ago, heavy rains have long plagued the City of Lubbock. In order to relieve some of the flooding, the community developed the South Central Drainage System Project. The engineering firm of Parkhill Smith & Cooper, Inc. (PSC), Lubbock, Texas, designed the system that is expected to decrease the volume and duration of city street flooding. The storm sewer directs overflow from the playa lake system on the south side of Lubbock to a discharge point near the city's water reclamation plant.
HOBAS Chosen
General contractor, Barnard Construction Company, Inc. of Bozeman, Mont., had used HOBAS centrifugally-cast, fiberglass reinforced, polymer mortar (CCFRPM) pipe previously on a sliplining rehabilitation project along Sloan Lane in Las Vegas, Nev. The installation subcontractor, Southland Contracting, Inc., of Fort Worth, Texas, has more than 10 years of history using HOBAS pipes in many types of installations including microtunneling. Consequently, the firms were confident that the pipe would perform excellently.
The original specifications included HOBAS and standard reinforced concrete pipe (RCP) for both the direct bury and tunnel portions of the project plus solid wall and profile wall polyethylene as well as corrugated metal pipe alternates for the direct bury portions. When the bids were tallied, the alternative materials did not represent substantial cost savings on the project, so HOBAS was selected.
Performance Confidence
"The HOBAS installation was just beautiful," stated Dave Taylor of Southland Contracting. "We could do things with HOBAS that we couldn't have done with other products."
As an installer, Dave said that he prefers the CCFRPM pipe due to its versatility and ease of installation. "We installed the pipe sections around three big tunneled curves and directly under the railroad. We also quickly repaired a piece of pipe that was damaged on site. When HOBAS was finished, you couldn't even tell it was repaired," he added.
When asked about the HOBAS product, Dave concluded, "I just think it is the greatest. Everyone from sales to customer service and field service was top notch. And they were there when we needed them."
Ahead of Schedule
The construction began in July 2001 and finished nine months ahead of schedule. Projections called for the $36 million system to be finished in April of 2004. In late June 2003 the first inlets opened and the new storm sewer became functional. Additional inlets opened later and now the entire system is operational.
The project included more than 10,000 feet of HOBAS CCFRPM pipes ranging from 24-inch to 72-inch diameter at depths of over 50 feet. The majority of the HOBAS pipe was installed by tunneling methods, either by itself or within a primary liner.
"Above Specification"
The specifications required HOBAS pipes to meet ASTM D3262 with minimum stiffness classes of 36, 46 and 72 psi depending on the depth of cover and the installation means. PSC inspected the pipe production and testing at the manufacturing plant in Houston, Texas. Robert Torres, EIT, inspector for PSC, said the "pipe performed at or above specification levels in all cases."
Nearing the end of the project, Torres summed it up, saying, "With the system now operational, all we need now is some rain to see how well it will work."
HOBAS pipe is manufactured in sizes from 18 inches to 110 inches in pressure and non-pressure classes. For more information, please contact HOBAS at 800-856-7473, 281-821-2200 or e-mail at [email protected]. Facts are also available at www.hobaspipe.com.
