Sahara Leak Location



1. What is Sahara?
Sahara is a uniquely sensitive inline acoustic leak location system that can pinpoint leaks with great accuracy in any water main or aqueduct of 12” (300 mm) diameter or greater, regardless of pipe type and material.

2. What are the benefits of Sahara?
Sahara can be used to accurately locate all leaks in a pipeline. This can be used to reduce water loss, or to confirm the structural and hydraulic integrity of a pipeline. It is well documented that most types of pipe leak before they break, making Sahara a valuable condition assessment tool.

3. How was Sahara developed?
Sahara was developed by WRc (Water Research Center) in London, UK, as an alterative to leak noise correlators for use in large diameter and non-metallic pipes.

4. How accurate is Sahara?
Over 1,500 surveys have been conducted using the system, which has demonstrated an accuracy of over 99%, with fewer than 1% false positives. Sahara has successfully pinpointed pinhole leaks and “weeping joints” with confirmed leakage rates as small as 0.25 gallons (one liter) per hour. It is the only proven system that can be used to assess the condition of transmission mains of any construction type greater than 12” in diameter.

5. How does Sahara work?
The Sahara system detects leaks in a pipeline by sensing the noise generated by a leak. As the sensor head travels along the pipeline, sounds within the pipe are picked up by the hydrophone in the sensor head. The system feeds the signal from the sensor head through the cable into the processing equipment for interpretation by the software and the operator. The operator is able to listen to the signal from the sensor, and visually monitor the signal using spectrogram software on a computer. The initial indication of a leak is when the operator hears the distinctive sound generated by the leak, which is then verified by the spectrogram. The system has been shown on many occasions to be extremely sensitive, finding leaks on the order of 0.25 gallons/hour in a pipeline at a pressure of 87 psi.

6. How is Sahara different from other leak location methods?
The system is distinct from correlators that are used to detect water loss throughout distribution networks. In operation, a sensor head attached to an umbilical cable is inserted into a live pipeline through any 2” (or greater) tap. Carried by the flow of water, the sensor travels through the pipeline for up to 6,000’ per insertion and pinpoints the exact location of a leak through identification of its distinctive acoustic signal. Once a leak has been detected the Sahara head can be stopped at the leak point. The head can then be detected within the main from the surface using the TUE Systems’ PipeSpy 2000™ locator unit, which has been incorporated into the Sahara system. The ground surface can then be marked accurately for subsequent excavation and repair.

7. Can Sahara detect air pockets?
Yes! Air pockets have a distinctive acoustic signature that can be recognized by the Sahara system. The size and extent of the air pockets can also be estimated.

8. Can Sahara be used in wastewater systems?
Yes! In 2005, WRc conducted ten trials of a Sahara system adapted for use in wastewater lines in the UK. A series of pilot studies conducted across North America in 2006 have demonstrated that the Sahara® leak detection system can be used in pressurized wastewater forcemains and siphons under typical North American operating conditions.

8. What are the benefits of Sahara Wastewater?
Sahara® wastewater is the first service to allow utilities to assess the condition of critical wastewater forcemains and siphons, such as major non-redundant lines, waterway crossings, and lines through environmentally sensitive areas, while keeping the line in service.