Leak management methods can prevent or reduce leakage volume and leak detection technology can improve the ability of water utilities to respond quickly and repair leaks.
Sometimes small leaks are detectable at the surface and easily identified. Such as exposed water pipes, ponding on road surface on dry days, overflowing warning pipes.
Underground, minor leaks would likely be undetected for years, resulting in loss of water and untold damages underground. For example, a minor leak of 4 liters per minute (small leak relative to large volume) will result in loss of over 2 million liters per year. The loss of money is small compared to the consequences of ignoring this leak.
Water from the leakage can erode the ground underneath the pipes, creating an underground void. Eventually the ground above cannot support the weight above and collapse. This can be especially dangerous on slopes as even a small void can start a landslide, whereas on flat grounds small potholes are more likely.