Everyone knows the saying “work smarter, not harder”. But in municipal collection systems, preventative maintenance strategies have followed a “work harder” approach. This is because, in the typical system, over 70% of gravity sewer lines are unobstructed, and using traditional time-based or rotational cleaning strategies, utilities waste resources by cleaning all pipes that do not need cleaning. This inefficiency is compounded by other common challenges such as employee shortages, aging infrastructure, budgetary constraints, and the need to conserve water.
To address this problem, leading “Smart Cities” are turning to a more efficient condition-based maintenance strategy to save time, money, and flushing water. Condition-based maintenance uses better information to smartly deploy sewer cleaning resources to the right pipe at the right time. One of these technologies is the Sewer Line Rapid Assessment Tool or SL-RAT®. Manufactured by InfoSense, the SL-RAT uses transmissive acoustics to rapidly assess for blockage conditions. Consisting of two parts, the SL-RAT transmitter sends a specialized tone through a pipe’s open airspace and the receiver listens for the known signal. Based on how much of the sound can pass through the pipe, the SL-RAT assigns a blockage assessment score very quickly and at low cost. Armed with this information, municipalities can reduce unnecessary cleaning while still proactively eliminating sewer system overflows and maintenance risks.
As an example, Campbell River, British Columbia highlights how acoustic inspection can optimize a collection system maintenance program. After incorporating the SL-RAT into their maintenance program, city leaders found that 86% of the lines assessed had excess flow capacity. Knowing that a majority of their system is free from blockage issues, Campbell River could better deploy their CCTV and cleaning resources and take focused action on the lines that scored poorly. While it would cost upwards of CAD $190,000 to clean their system, it only costs approximately CAD $11,000 after inspecting with the SL-RAT. With an average cleaning cost of approximately CAD $3 per meter, it is estimated Campbell River saved over CAD $150,000 while reducing the risk of pipe blockages and overflows.
From Charlotte, North Carolina to Singapore PUB, over 1300 utilities around the world have tried the SL-RAT. Still unsure? Try this cost calculator to see how condition-based maintenance, with the SL-RAT, can enhance your existing program.
