Environmental Engineering Reference
In-Depth Information
doubtful quality. Although excellent water service, especially in municipalities,
is generally available in the United States and in many developed areas of the
world, consumers and public officials must not have tended to become compla-
cent. Many of the older water treatment facilities have distribution systems in dire
need of replacement. The American Society of Civil Engineers in 2001 acknowl-
edged the need for replacement of aged facilities in 54,000 water treatment plants
in the United States at a cost of $11 billion, not including the additional cost to
meet new drinking water standards.
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Compounding the problem is the shrink-
ing availability of revenues within the tax structure of communities such that, in
some instances, funds may have to be diverted from maintenance, operation, and
upgrading of the water supply system in order to cover other expenses. It is also
sometimes forgotten that in developing areas of the world, a convenient, safe,
and adequate water supply, in addition to affording protection against waterborne
diseases, makes possible good personal hygiene, including hand washing, sani-
tation, household cleanliness, and clean food preparation. In addition, it obviates
the need to wade in schistosome-snail-infested streams to undertake the laborious
and time-consuming task of transporting water (see the section “Schistosomiasis,”
later in this chapter). An interesting sidelight is the controversy that emerged over
the construction of the Aswan High Dam in the early 1960s. A large impound-
ment was formed on the Nile River to serve both as a water supply and flood
control. It had been argued that the dam lowered the downstream level of the Nile
River and, combined with large-scale irrigation, brought increased incidence of
schistosomiasis. This may not be the case. With the improved level of sanitation,
clean water, and medical facilities, schistosomiasis has actually been reduced
from over 40 percent in predam years to 10.7 percent in 1991.
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Adequate drinking water statutes and regulations and surveillance of public
water supply systems are necessary for their regulatory control. This is usually
a state responsibility, which may be shared with local health or environmental
regulatory agencies. The EPA recommendations for a minimum state program
include
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:
1. A drinking-water statute should define the scope of state authority
and responsibility with specific statutory regulations and compliance
requirements. Regulations should be adopted for drinking-water quality
standards; water-supply facility design and construction criteria; submis-
sion, review, and approval of preliminary engineering studies and detailed
plans and specifications; approval of a water-supply source and treatment
requirements; establishment of a well construction and pump installation
code; operator certification; provision for state laboratory services; and
cross-connection and plumbing control regulations.
2. The surveillance of public water-supply systems should involve water qual-
ity sampling — bacteriological, chemical, and radiological, also turbidity
and residual chlorine; supervision of operation, maintenance, and use of
approved state, utility, and private laboratory services; cross-connection
control; and bottled and bulk water safety.
