Underground Leakage and its Relation to Mains and Services

One of the most convenient ways of reporting underground leakage in flow lines and distribution systems is in gallons per day per mile of pipe or gallons per day per foot of joint. Either of these figures is a fair indication of the efficiency of the transmission system only when there are no service connections to it. As soon as otjier means for water to espape are introduced, it is absolutely unfair to report or consider leakage as a function of the length of the main. Unfortunately, a better system does not readily offer itself because of the way leakage figures are determined. It is also unfortunate that the method of arriving at the amount of water lost in transmission involves so much guess worlc, because lack of accuracy is responsible to a great extent for the fact that large water losses are so easily condoned. In determining the amount of water escaping underground, the usual way is to account for all that is fairly measurable and then to ascribe the remainder to leaks» This involves considerable estimating and the net result, as far as unaccounted for water is concerned, is nothing more than an estimate. On account of its unreliability, it is not taken as seriously as it should be. In fact, many water works men have come to look upon a large underground loss as a legitimate expense and, consequently, disregard it. In reality, there is small excuse for this condition because pipe may be laid so that it will be almost absolutely tight and, if proper material and workmanship are used, there is no reason why the pipe should not remain tight indefinitely. In examining water works statistics, it is not at all unusual to find many systems reporting losses of from 20 to 50 per cent of the water pumped. If this were true of those cities and towns where water is still sold on a flat rate basis, it might be ascribed to waste within the premises. As a matter of fact, this is not the case and many towns