MAUL’s Latest Tool for Locating Plastic and Concrete Water Lines

The majority of sub-surface utilities are locatable using standard locating methods such as electromagnetic (EM) based locators and the Ground Penetrating Radar (GPR). Although these instruments remain the most prominent on the mar­ket, they both have limitations when it comes to locating plastic and concrete water lines. A vast number of utilities can be identified through the presence of metal in the utility itself or the density of an object. Many utility companies are beginning to use metallic tracing wire or tape with their plastic and concrete pipes to eliminate the element of costly locat­ing measures in the future; however, a significant portion of older utilities have not benefited from these new practices. Mid-Atlantic’s newest instrument, the RD500, bridges the gap between older projects and new project developments providing an effective alternative to EM locators and the GPR when absence of metal or environmental obstacles interfere.

Standard Locating Instruments

EM based technology works by emitting radio waves and turning the metal in the utility being located into an antenna for the radio signals. Tools such as the Metrotech 9800, i5000 MetroMark, Metrotech 810, etc. can be used to find a significant portion of utilities if metal is present. Additionally, the size and design of this tool makes it easy to use and take most anywhere on construction sites, making it a desirable choice for utility locating.

Other locating instruments, such as the GPR, are usually able to detect the utilities that the EM tools are unable to detect as it relies on the reflectivity of objects beneath the surface rather than metallic objects. It is fairly easy to see con­crete and plastic utilities with the GPR as well as underground vaults and voids. The primary weakness of the GPR lays in issues that arise from soil quality; a common issue in the DC area. Virginia has an abundance of clay soil, a problematic natural contaminate that creates added challenges for the professionals working throughout the region.

RD500 Plastic and Water Line Locater

The RD500 is the best tool for locating plastic and concrete water lines in clay rich areas as it is a tool that doesn’t rely on the metal in pipes nor is it limited by the consistency of the soil in the area. In contrast to the techniques described, the RD500 uses sound waves rather than radio waves to generate feedback from non-metallic utilities. Technicians attach instruments to fire hydrants, water meters, and water spigots to generate sound through a vibrating coil located in the sending device rather than use of radio signals. The receiver is then used to listen for the sounds transmitted through the water within the pipes to locate the underground pipes. As long as pipes are pressurized and active, it is possible to ‘hear’ their location rather than to ‘detect’ it.

Only three companies within the DC metro area have the technology and expertise to overcome the challenges of locating non-locatable water lines in clay soil, one of them being Mid-Atlantic. Mid-Atlantic’s experience, expertise and documented success rate with this instrument provide a unique solution for clients throughout the area.