Northern Utility Services

Northern Utility Services

Alaska's Community Water System Specialist

Leak Detection

Little Leaks = Big $$$

Leak Detection makes business sense, and Northern Utility services provides state of the art leak detection services throughout the state of Alaska. Whether you simply need to find a service line leak, survey an entire distribution system, or obtain an emergency leak detection, our trained technicians are equipped to meet your needs.

Water Service Leak
Acoustic Leak Detection

Our leak detection efforts have saved our customers millions of dollars by eliminating systemic losses, expensive exploratory excavations, and by providing detailed reports to justify grants and low interest loans. Our successes have ranged from  locating a tiny leak on a mile of 48 inch Steel main to locating a leak on HDPE Arctic Pipe. We have located hundreds of leaks in Anchorage, Wasilla, Kenai, and all over the state of Alaska.

Leak Detection Process

As part of our service, we provide an Initial consultation to learn system layout, leak symptoms and other information that may provide clues to narrow the search. Next, we utilize acoustic listening equipment to listen on valves and service lines to narrow down the search area. Finally, a leak noise correlator or tracer gas detector is used to pinpoint leak locations.

In the case of a system-wide leak survey, leak noise loggers are deployed throughout the system to record leak noise and develop a leak noise profile for the entire system. Leaks are then pinpointed and a comprehensive report is prepared to communicate the findings

Methods of Leak Detection

Acoustics
Before using correlation (as described below), we use a high quality digital listening device to quickly survey the target area to identify the general location of the leak. In larger distribution networks, a series of correlating loggers will be deployed throughout the system to narrow the search area.

Correlation
Leak Noise Correlation is a method for finding and pinpointing leaks in pressurized water pipes. A leak in a pipe under pressure creates noise that travels along the pipe, its contents, and through the surrounding ground.

Correlation
How Leak Correlation Works

When two highly sensitive microphones are attached to a pipe with a leak, the sound from the leak takes longer to travel to the microphone furthest from the leak. By utilizing sophisticated software analysis tools and known sound travel speeds in different pipe sizes and materials, leaks can often be located within feet or even inches.

Hydrogen Tracer Gas Detection
Due to its small and highly energetic molecules, hydrogen can be a useful tool for underground leak detection. A Hydrogen/Nitrogen gas mixture is introduced to the leaking section of pipe and allowed to migrate up through the soil where it can be detected with a sensitive hydrogen gas detector. Tracer gas leak detection can be an effective tool when searching for leaks on challenging pipe materials such as HDPE, PVC and Arctic Pipe and can even be effective in locating leaks under uncoated concrete slabs.

Possible Complications

Although underground leak detection employs finite scientific principals, many variables can cause inconsistent or inaccurate results. By eliminating these variables, leak detection efforts are more likely to provide accurate results. These variables are:

  1. Pipe types, locations and depths. If location, or pipe routing is unknown, Northern Utility Services is equipped to locate underground piping. However some pipe materials can be difficult or impossible to locate using standard methods, and as a result, only a general leak location may be possible.
  2. Ambient Noise. Although our equipment employs sophisticated noise filters, ambient noise can affect the results of leak noise correlations. To eliminate excessive noise, our leak noise loggers are capable of delaying the noise recording until the most quiet time of day or night.
  3. System Usage. Water flow in the system causes noise of differing degrees, and can produce erroneous or confusing results. To minimize the effect of system usage, our leak noise loggers are capable of delaying the noise recording until a time of day when normal usage is minimal.
  4. Radio Interference. Our primary leak correlation system uses radio signals to transmit the leak noise data from the two microphones to a centrally located receiver and processing software. If there is radio interference from something like a large radar tower, we may have to use other means which may be less accurate.
  5. Tracer gas methods can be affected by impermeable soils such as clay and frozen ground, and accurate location of the targeted water line is critical to success.

Free Consulation

Each leak detection performed by Northern Utility Services begins with a free consultation where a leak specialist will learn about your particular circumstances and recommend the best technology. To request a free consultation, please use the “Request a Quote” button above, and a leak detection specialist will contact you right away.