Negative pressures have been documented in a variety
of distribution systems as a result of either
unintentional (e.g., power outages) or intentional
(e.g., pump stoppage or startup tests) circumstances.
The production of transient low and negative pressures
in otherwise pressurized potable water supply distribution
systems creates the opportunity for contaminated
water to enter the distribution system from external
environments. However, few systematic or long-term
studies have monitored real distribution systems for the
occurrences of transient low and negative pressures
under field conditions. A comprehensive and lengthy
study was conducted to monitor the occurrence of low- and
negative-pressure transients and to evaluate the
effect of a variety of operational situations on the development
of these events. The authors also compared the
efficacy of electronic and mechanical pressure-monitoring
devices for detecting transient pressure surges.
Because of the danger of contamination, the water
supply profession should be aware of the occurrence
and potential adverse effects of transient low and negative
pressures. Water providers can use the information
in the article to aid in the design of a pressure-monitoring
program to help determine their systems' susceptibility
to low and negative pressures. Such a program
could use hydraulic surge models to assess the potential
for pressure transients to occur throughout the system
under a variety of operating conditions. Study results
also point to the usefulness of high-speed electronic
pressure monitors for detecting surge events. Includes 12 references, tables, figures.
| Edition : | Vol. 96 - No. 11 |
| File Size : | 1
file
, 510 KB |
| Note : | This product is unavailable in Ukraine, Russia, Belarus |
| Number of Pages : | 15 |
| Published : | 11/01/2004 |
