P1 Takes on Challenging Valve Replacement: Project Profile on Atherton Waste Water Treatment Plant

The words “raw wastewater” might make you cringe, but the P1 crew working on the project at the Atherton WWTP were ready to take the plunge.

When challenges arose, quick thinking on the team's part not only kept their feet (mostly) dry, but also resulted in a successful pump discharge valve replacement.

The plant, located in Independence, MO, services multiple Missouri cities, including Independence, Blue Springs, and Lee’s Summit, with a total land area of approximately 278 square miles. The plant maintains eight pumps that keep the entire area running.

Recently, P1 took on the job of replacing two of these 36” valves.

The critical valves and their associated pumps are the primary valves used at the entrance to the plant. 

All raw wastewater collected in the Little Blue River drainage basin flows by gravity through the sewers to the trash rakes, and into the wastewater pump station. These valves are two of the eight pump valves that keep the entire area running. 

With just a short five-day timeline, the project consisted of isolating the plant to a single side (A side and B side, in the raw wastewater pump station), removing the old valve, and installing the new valve. Once the first valve was complete, the plant isolated the opposite side and the process was repeated.

The supply chain delays affecting so many businesses right now presented a problem early in the process.

Senior Project Manager Zach Kittle explained that the valve bodies, manufactured in Germany and delivered to the U.S. factory, were missing part of the actuator, keeping the valve assembly from completion.

“The part for the actuator was in a container somewhere in the rail yard in Chicago," Zach said. “It was stranded there from June until September, and the completed valve didn’t get to us until October."

When the valve replacement finally got underway, there were a few more challenges.

At the entrance to the facility, 96" diameter pipes run to each side of the raw wastewater building.  In order to shut this water off, 9’ x 12” stop logs are installed, which slide down into a channel. 

The stop logs - 15 of them - are stacked onto one another.

The hope is that the bottom of the channel is clean so the stop logs can sit flat on the bottom, and securely on top of one another. Any gaps would allow water to flow by.

When Plumbing Foreman Danny Bartow and his team began to replace the first valve, it was discovered that the bottom of the stop log channel was completely full of “solids” from the incoming raw wastewater.

The facility had to shut down the plant and drain the water out of the inlet so high power hoses could be used in an effort to clean out the stop log channels.

While the plant was down, the inlet for Raw Wastewater Valve #1 had two to three feet of solids in the bottom of it, requiring a hydro-vac truck to clean out the bottom of the channel.

After the channels were cleaned out, Danny and his team installed two sets of stop logs in two channels for a more positive shut-off.

After removing the first existing valve, and installing the new valve, the team attempted to install the coupling that connects the facility’s existing piping with the new nipple that had been installed on the end of the valve. 

The drawings called out the existing piping as 36” pipe, but Danny and his team couldn’t get the new coupling on the existing pipe. 

The existing piping was, in fact, a “non-standard” pipe size, with an outside diameter of 36-5/8” as opposed to the noted 36”. 

“Danny reacted immediately and ordered two new couplings, to be delivered ASAP,” Zach said.

”Luckily, the manufacturer was able to build one of them over the weekend and overnight it to us.”

When the water flow on the 2nd valve wouldn’t stop, Danny and his crew had the solution.

Danny explained how the crew installed rented grinder pumps into the incoming water pit and were pumping the water from the side of the plant they would be working on to the other side of the plant which was in now in operation from the recent replacement of valve #2.

“With this solution, we were able to get enough water moved over to the operational side of the plant so the stop logs finally sealed up enough to begin the removal of the valve,” Danny said

After the valve installation was complete, a factory representative performed the valve startup.

Zach noted that Atherton WWTP was great to work with.

“They were very understanding of the supply issues and willing to work through all the schedule changes,” Zach said.

He also noted the work would not have gone as smoothly without the quick-thinking of Danny and his crew. “Danny’s ability to troubleshoot quickly along with his crew working through all the obstacles really made this project a success,” Zach said.