As the city of Houston tackles the challenge of aging infrastructure, the Department of Public Works and Engineering is looking at how to best outreach to contractors who can handle the task.
Many of the advertised projects that are bid and managed by the city have an estimated value between $2 and $4 million. The duration is about 360 days per project and usually covers an entire neighborhood or about 15 to 20 streets. Public Works Managing Engineer Joe L. Smith, P.E. says the replacement projects are prompted by the need to replace lines that are either old or are causing water quality issues.
“These water lines fall in the age group between 30 to 50 years old, are cast iron or older type material,” Smith pointed out. These types of projects can also be quite costly and disruptive to a neighborhood and many municipalities like Houston require contractors to use the auger method form of trenchless installation. This type of process is less-invasion to residents and restoration is less costly.
Controlling cost is an important part of all water main replacement projects so Houston uses unit-price contracts. “This allows us to look at each portion of the project and examine the bottom line for each portion — which keeps cost down. We can manage the project better to keep it on track which, in most cases, speeds up the project,” Smith said.
This strategy comes in handy when replacing existing lines that usually are four to 12 inches in diameter. The common practice of cut, plug and abandonment of older lines keeps the projects moving and are less disruptive, making restoration a little easier.
The city of Houston has a “Hire Houston First” policy in order to encourage local contractors to bid on available opportunities. However, the door is still open for other industry leading contractors who have the skill set to handle these projects to be the low bidder and then, in many cases, use local firms as sub-contractors.
Houston does about 10 to 15 water main replacement projects per year with plans to increase this over the next five years. “Our goal is to get between 10 to 15 contractor companies to bid on projects. Interested contractors should visit the city of Houston Public Works website at http://bidsets.publicworks.houstontx.gov/ for more information,” Smith stressed.