AFC SEMPER RPM: Topsfield Water Department’s Answer for Identifying Water Hammer and Other System Pressure Issues

The Topsfield Water Department purchased three of the AFC SEMPER RPMs and deployed them in November 2020. The units have helped the water department identify water hammer and other system pressure issues before they become a problem.
The Topsfield Water Department purchased three of the AFC SEMPER RPMs and deployed them in November 2020. The units have helped the water department identify water hammer and other system pressure issues before they become a problem.

For any water system, water hammer, also known as pressure transients, pose significant threats, from leaking joints to service connection failures and even pipes that burst. The damages resulting from these events can be costly to repair and leave customers without water. The Topsfield Water Department in Topsfield, Massachusetts, has found an answer for identifying water hammer and other system pressure issues before they become a problem. The solution is the AMERICAN Flow Control SEMPER™ Remote Pressure Monitor (RPM). Introduced in February 2020 in partnership with Trimble Water, the AFC SEMPER RPM provides utilities with the data needed to monitor water pressure throughout their systems and help identify leaks and reduce non-revenue water.

Among the many benefits of the AFC SEMPER RPM is its ability to be used year-round. In warmer months, it can be installed on fire hydrants, and in colder months, it can be attached to a tap or other asset inside any building, vault or enclosure. The AFC SEMPER RPM is a wireless, battery-powered, pressure recorder that can be installed on any system asset or fire hydrant.
Among the many benefits of the AFC SEMPER RPM is its ability to be used year-round. In warmer months, it can be installed on fire hydrants, and in colder months, it can be attached to a tap or other asset inside any building, vault or enclosure. The AFC SEMPER RPM is a wireless, battery-powered, pressure recorder that can be installed on any system asset or fire hydrant.

One recent example from Topsfield, Massachusetts, involved a transmission line carrying raw water into the utility’s water treatment plant. “We saw a 60-pound total pressure surge on this transmission main,” said Topsfield Water Department Superintendent Greg Krom. “Regular pressure is about 75 pounds [75 psi], but we were seeing a swing of 30 pounds [30 psi] in both directions. Once we identified the water hammer on that line, we determined it was caused by turning the source water on and off too quickly. We were able to adjust the timing of the surge control valves to reduce the water hammer occurrence.”

Krom said the AFC SEMPER RPM was attached to a tap on the transmission line for this particular use, showing its versatility to be used on system assets as well as hydrants. In colder climates, such as those in Topsfield, the ability to move the AFC SEMPER RPM to interior assets is especially beneficial. E.J. Prescott Geographic Information System (GIS) Specialist Nick Bates said, “The AFC SEMPER RPM is a device that can be used year-round. In warmer months, it can be installed on fire hydrants, and in colder months, it can be attached to a tap or other asset inside any building, vault or enclosure.”

The Topsfield Water Department also placed the AFC SEMPER RPM in a pressure zone that was served by a booster station, because it was seeing large swings in system pressure. “If someone used water, we would see some fluctuations,” Krom said. “As a result of the reporting data we received, a hydropneumatic tank was installed that allowed us to better manage system pressure.”

A customer also reported a problem with a fire sprinkler line and needed to determine if the issue was on the customer or the water department side. “I was able to look at the reporting and the time stamp within the graph, and see the issue only happened when the customer turned the water on,” Krom said. “We knew it was something with the customer’s system and not ours, and repairs were made. It was very useful.”

The Topsfield Water Department purchased three of the AFC SEMPER RPMs and deployed them in November 2020. The water department currently has more than 1,800 accounts and serves about 6,000 people. Its distribution system contains about 50 miles of pipeline – 30 miles is ductile iron and 20 miles is asbestos cement pipe, which Krom said is extremely brittle and must be closely monitored.

“The Topsfield Water Department understands the value of technology and is using the AFC SEMPER RPM in strategic locations across its system,” Bates said. “It has allowed the water department to figure out water hammer and efficiency issues. Topsfield can take the data and adjust run times to make operations more efficient.”

Through configurations of the Trimble Unity software's impulses, the AFC Semper RPM can detect water hammer by sampling up to 256 times per second. Tracking these events are critical when trying to troubleshoot pressure issues. This information provides the severity and the time of the event, so that data can be used to verify why the event happened. In the graph shown, a water hammer event was occurring in one of Topsfield’s transmission water lines. By deploying the AFC Semper RPM, the water department was able to track the trends in the data and resolve the issue.
Through configurations of the Trimble Unity software’s impulses, the AFC Semper RPM can detect water hammer by sampling up to 256 times per second. Tracking these events are critical when trying to troubleshoot pressure issues. This information provides the severity and the time of the event, so that data can be used to verify why the event happened. In the graph shown, a water hammer event was occurring in one of Topsfield’s transmission water lines. By deploying the AFC Semper RPM, the water department was able to track the trends in the data and resolve the issue.

Prior to purchasing SEMPER RPM, Topsfield had used a data logger, but it wasn’t providing all the information needed and wasn’t user friendly. “Because this is a cloud-based system that can be put on a main or a fire hydrant, it was easy to set up,” Krom said. “One of the benefits of the software is you can go back in time and look at historical data, and that only adds to its value. We had used Trimble GPS units and software previously. It was an easy decision to go with SEMPER RPM. It’s great and does everything I’m looking for at this time.”

As it relates to the Trimble Unity® software used with the SEMPER RPM, Krom said he likes that it’s very accessible, and he can view data on his phone, iPad or computer. “The SEMPER RPM is well made and has all the features anyone would want,” he said. “The software makes it very easy to view and analyze data. Everyone at AFC and E.J. Prescott has been very helpful as well and answered any questions we’ve had along the way.”

E.J. Prescott Territory Sales Manager Chris Granese said, “The numbers never lie. The information the AFC SEMPER RPM provides not only helps the people on the ground doing the field work, but it also shows management the problem so steps can be taken to fix it.”

The AFC SEMPER RPM is a wireless, battery-powered, pressure recorder that can be installed on any system asset or fire hydrant. It is both wireless and Bluetooth capable, and data is transmitted and seamlessly integrated with the cloud-based Trimble Unity® Remote Monitoring (RM) software for quick and easy data analysis. To learn more, visit https://american-usa.com/products/valves-and-hydrants/semper/.