AFC SEMPER RPM: The Ultimate Leak Detector

Almost two years ago, a local lumber company contacted the village of Montgomery, Illinois’ Water & Sewer Department because its water meter was moving and causing a loud thumping throughout the building. "When I first heard it, I knew it was water hammer,” said Water & Sewer Superintendent Jeremy Moss. “I then began researching to see what products were available to help us find and resolve the issue.” [In a water system, water hammer is an event where water that is in motion suddenly stops or changes direction.]

What Moss found was the AMERICAN Flow Control SEMPER® Remote Pressure Monitor (RPM), a wireless, battery-powered pressure recorder that can be installed on any hydrant or system asset. The AFC SEMPER RPM’s “Lift and Shift” mobility allows utilities to move the units throughout their systems to monitor water pressure, help identify transients and reduce non-revenue water.

An AFC SEMPER RPM was secured by Moss and placed in the mechanical room next to the water meter at another business on the same eight-inch line as the lumber company. “We began to see a pattern of water spikes during the day and less fluctuation at night” Moss explained. “One afternoon in early December, we saw a pressure swing of more than 77 psi on the eight-inch water line.”

We can put the units throughout our system and have started looking at locations where we’ve had main breaks and where we have our highest water users. The technology paints a picture you wouldn’t normally be able to see.

As the water hammer investigation at the lumber company continued, the village of Montgomery also had a main break occur on a 12-inch water line running to its treatment facility. The main break occurred near where the eight-inch line and the 12-inch line meet. “We placed an AFC SEMPER RPM on a hydrant connected to the 12-inch line and discovered a transient event was occurring when one of the wells started up and shut down,” Moss said.

“We weren’t certain if the main break was caused by the water hammer at the lumber company,” Moss explained. “But from the sampling information we received from the AFC SEMPER RPM, we had a better indication of space and distance and where the water hammer might be occurring.”

Moss and his team then moved the AFC SEMPER RPM back up the eight-inch water line to a hydrant near a concrete company. “What we discovered was ungodly,” Moss said. “When we captured one of the events, it stayed off scale for nine minutes with readings over 300 psi. A check valve at the facility locked the pressure in until the joints started leaking. The information was there; we just couldn’t see it.”

The water hammer was caused by a pneumatic actuator valve that was fully opening and then instantly shutting. The pressure swings were occurring on a water line that feeds a boiler and fills up day tanks on concrete trucks. A speed control was installed on the pneumatic actuator valve, and the problem was solved. “By controlling the speed, we were able to get a slow open and close, and fix the issue,” Moss said. “The transient event was so severe it was causing pressure surges at the local business about 1,000 feet away. This shows how far a transient event or water hammer can travel on the same line.”

Moss noted the pneumatic actuator valve was incorrectly identified as a muffler by the company and taken out of service. “This was what led to the improper operation and function of the valve,” he said. “It all makes sense once you figure out the operation of what was causing it.”

According to Moss, the Water & Sewer Department chose to purchase the AFC SEMPER RPM because of its portability and sampling rate of up to 256 samples per second. “We can put the units throughout our system and have started looking at locations where we’ve had main breaks and where we have our highest water users.

“I would recommend the SEMPER to other water utilities because of its ease of use and the detailed information it gathers,” Moss said. “The technology paints a picture you wouldn’t normally be able to see. The AFC team, first Mike Lane and now Steven Juzwiak, were very consistent and able to navigate any problems we had.”

The village of Montgomery’s Water & Sewer Department maintains about 140 miles of water mains and serves about 30,000 people. It is currently completing an eight-year capital improvement program to install about 26 miles of water mains and replace any water mains installed prior to 1970.

To learn more about the AFC SEMPER RPM, visit AFC SEMPER® Remote Pressure Monitor (RPM) with Impulse Technology | AMERICAN (american-usa.com).