As the Valve Turns...

As the new West Parish WTP construction advances, we are learning how fortunate we are to have a skilled and committed Water Operations staff, who combine their expertise with creativity to step up when challenges arise. 

Recently, that expertise was put to the test with Valve 215, a 100-year-old, 36-inch gate valve. This valve was central to recent efforts to re-route transmission mains around the old slow sand filters to allow for continuous treatment while the new plant is constructed. Closing the gate valve would require connecting a gate machine to a gear assembly located in an underground vault that ultimately moves the valve.     

Water operations staff estimated that this closure of the valve was only the second time the valve had been turned in 100 years. A few test turns suggested the gear assembly would move. But when Water Operations staff began working to close it, they discovered that the gear assembly was severely worn and no longer functional after only 26 turns (out of an estimated 250-350). Replacing it using standard methods would have taken weeks, which was time both the Water Operations staff and the construction crews simply did not have. 

 The old gear assembly that stripped when turned only 26 times.

That’s when our staff’s quick-thinking and creative problem-solving made all the difference. 

Recognizing the urgency of the situation, Provin Mountain Resident Manager Mike Townsley located a slightly smaller spare gear assembly from an old valve in storage and developed a creative plan to re-machine it and adapt it for Valve 215. Working alongside several other members of the West Parish crew, the team custom-fabricated brackets, added new components, and carefully tested the assembly, all while working safely in a confined underground vault. 

Mike Townsley in the vault working on the valve.

The crew carefully operated the valve in reverse, moving slowly to avoid damaging the gear assembly. Water Operations Manager John Decker spent eight hours meticulously coaxing the valve shut. Meanwhile, staff had a Plan B in place to throttle a different valve and adjust plant operations accordingly if needed.  

After 225 turns, the valve finally resisted further movement, indicating it was fully seated, while the gear assembly remained intact and in good condition. The valve was successfully closed just in time to complete a critical project tie-in. Creative teamwork and know-how among Water Operations staff saved valuable time, ensured system reliability, and kept construction moving forward. 

New gear assembly installed.

Celebrating the shut valve.