The assignment was critical: Des Moines Water Works’ leaking backflush valve – there since 1987 – needed to be replaced within a narrow 36-hour window. The Water Works had a 36-hour stored supply of water. After that, the water supply would run out.

The tight timeframe required Baker Group to overcome a number of significant challenges, which required an important amount of planning. “We had our Mechanical Engineers, Structural Engineers and Prefabrication teams all on the task,” says Jim Fetters, Baker Group Project Manager. “The possibility of leaving residents without water was incredibly stressful. We wanted to ensure there was no disruption of service.”

But, Fetters’ and Baker Group’s prep work paid off, says Tony Knox, Water Production Maintenance Manager for Des Moines Water Works. “The planning, preparation and execution demonstrated by the Baker Group team showed a high skill level and professionalism to complete such a critical task in a confident and timely manner,” Knox says.

Preparation included:

• Fabricating a tool to remove the 2,600-pound valve. The ceiling height prohibited removing the backflush valve using conventional methods, such as a gantry, chain fall or crane. “We designed and prefabricated a special tool that would fit onto a forklift and underneath the valve, which would then slide in and out of the space,” says Fetters.
• Retrofitting the valve. The new, manufactured backflush valve was ¼-inch shorter than the old one. A washer-like spacer with 36 precisely placed holes for bolts was designed, fabricated and tested in advance.
• Removing rusted-on bolts. Loosening and removing the 72 rusted-on bolts would be a time-intensive task. The Baker Group team removed and replaced a few bolts at a time in advance.

When the time came to replace the valve, Baker Group’s Mechanical team – three plumbers and one equipment operator – was led by Foreman Nick Lause. “Nick was absolutely key to this project’s success; he did a fantastic job,” Fetters adds. 

The team worked around the clock to execute the critical task. Because the bolts removed easily, the specially made tool worked as planned, and the spacer fit perfectly, Des Moines Water Works’ filtration system was operating leak-free long before the 36 hours were up. The water supply never faltered.