Substituting microtunnel installation of HOBAS jacking pipes for open cut construction has benefited everyone on the Maxey Rd. Pump Station project in Houston. Of the two miles of new interceptor lines required, nearly 4000 ft. of 24", 30" and 36" pipes were switched with the City's approval. The completed project reverses the sewage flow to an improved treatment site.

Off - Setting Costs

Although the project was designed for open cut installation, the City indicated other methods would be considered acceptable. With this knowledge, successful bidder BRH Garver of Houston planned to microtunnel the deep cuts (25 to 35 ft.). The higher pipe cost and more expensive equipment cost was off-set by other construction savings including:

• Elimination of continuous sheeting.
• Reduction of spoil haul away and disposal.
• Less cement-stabilized sand backfill and street repaving.
• This cost balancing allowed Garver to offer this "community friendly" installation method to the City at no extra cost.

HOBAS Most Reliable

Garver selected HOBAS jacking pipes for several reasons including:

• Lower jacking loads required due to the dimensional consistency and smooth exterior.
• Highest reliability because of the square ends, resilient material and consistent high strength.

These benefits result in operational flexibility and lower risk. With most of the pipe installed, typical jacking loads on drives of + 300 ft. have been 25 to 50 tons. As in the past, the pipe installation was trouble-free. The completed lines were air tested to assure their integrity.

Benefits to All

The HOBAS pipe-microtunnel substitution provided many benefits to everyone including:

City of Houston:

• Superior sewer.
• Less cutting and patching of streets.
• Reduced wear on streets.

Community:

• Fewer detours during construction
• Less disruption and noise.

BRH Garver:

• Safer, easier job.