Drought Brings Challenges To City Water Departments

By Jeff Griffin, Senior Editor | May 2012, Vol. 67 No. 5

“A study by the University of Houston determined that pipes buried within five feet of natural ground were more likely to rupture due to changes in the moisture content of the high plasticity clay soil that is present in most of the Houston area,” Wright said. “While A/C pipes appeared to be the most vulnerable and impacted the most, fortunately most of the breaks seen on this type of pipe could be repaired using wraps and clamps. Cast iron pipes often displayed splits which were several feet in length. These types of repairs required more extensive excavation and pipe replacement.”

Houston addressed the 2011 line breaks with city crews supported by temporary employees and hired contractors. Extra equipment was rented as needed. On average, 29 city water repair crews and 25 contractor repair teams were deployed daily.

“A crew consists of a team leader and two assistants,” Wright explained. “This number may vary depending on the complexity of the job. The department has a range of non-specialty (pickups, dump trucks, etc.) and specialty equipment (cement mixers, backhoes, etc.). Typically, a repair team deploys with a heavy repair truck towing a backhoe on a 15 ton trailer. Support is provided by a roving area supervisor and other valve turning personnel riding in pickups. Dump trucks transport spoil and fill material from and to repair sites on an as needed basis.”

Cavalry
Wright said when officials recognized the circumstances required additional resources to make repairs, they reached out to the contracting community through the Houston Contractors Association.

“Emergency provisions of state procurement laws allowed the department to procure their services on an expedited basis,” Wright continued. “Informal bids allowed work to start in days instead of the usual months. Repair contracts ranged up to $1.5 million. To promote small businesses, a number of contracts in the $100,000 range were also awarded. Ten contracting companies were retained to make repairs, restore property, and provide support assistance. Typically, each repair cost between $ 3,000 and $ 4,000.”

When breaks occurred, facilities providing essential services received priority.

“Repairs at Houston’s famed medical center area are one example,” said Wright. “So were the city’s airports, sports arenas, convention centers, major shopping malls and educational institutions. One break necessitated interruption of service to a federal detention facility. The repair was scheduled during the evening hours and caused no disruption of operations at the institution.”