AWWA JAW62683

Pressure control can be an effective way to reduce leakagein water distribution systems. The authors present results froma laboratory study conducted to determine the relative importanceof soil versus orifice head loss in controlling leakage ratesand to determine an appropriate equation to define this flow.The study demonstrated that the nature of the leak reductioncould be described by a dimensionless orifice/soil (OS) headloss number.In most leaks, head loss through orifices is more importantthan head loss through soil. For high OS number values, orificehead loss dominates; for low values, soil head loss dominates. Inmost real-world cases, the OS number is large so that modelingleakage with flow emitters (orifice equation) is appropriate. Computermodels may also be useful in evaluating the effectiveness ofpressure-reduction schemes for reducing leakage.However, controlling pressure does not only reduce leakagevolumes, it also can have an effect on service pressure forcustomers. Thus it is important to determine the effect of anychange on customer pressure before pressure control is introduced.Using a hydraulic model of the system, a utility managercan determine the effect of pressure reduction on both leakageand customer pressures. Includes 16 references, figures.

Product Details

Edition:

Vol. 98 - No. 4

Published:

04/01/2006

Number of Pages:

9

File Size:

1 file , 310 KB