MIL-HDBK-1164
Inspect and lubricate gates and any similar apparatus as required.
4.6.2
Reservoirs. Maintenance of reservoirs usually involves one or more of
the following tasks: watershed sanitation, surveillance, and control; silt removal; and
control of nuisance organisms.
4.6.2.1
Water Quality Control. The quality of water in the reservoir depends on
the quality of water in the feeding stream. Various sources of pollution are possible.
Operating functions consist of surveying the watershed to locate possible
contamination sources and controlling those sources as much as practical. Total
ownership of the watershed is seldom possible, so agreements with others may be
necessary to ensure a high-quality water source.
4.6.2.2
Silt Removal. Silt will eventually fill all reservoirs. Reservoirs are
designed with a siltation basin that may account for half or more of the total reservoir
volume. The extent of silting can be determined by comparing the reservoir volume
with the initial reservoir contour or prior sounding surveys. This information can be
used to calculate the storage capacities available for various water levels in the
reservoir. When necessary to extend the life of the reservoir, silt can be removed by
dredging.
4.6.2.3
Control of Nuisance Organisms. Control strategies for a number of
nuisance organisms commonly found in water supplies can be found in par. 2.2.6. This
publication covers the most common organisms, including algae, bloodworms, zebra
mussels, actinomycetes, nematodes, rotifers, Giardia, and Cryptosporidium.
4.6.3
Intakes. The intake is an important part of the water supply system.
Unless it is properly designed, maintained, and operated, it can readily be the cause of
a partial or complete shutdown of the entire system, often causing difficult and
expensive repair.
4.6.3.1
Operation. Many intakes are fitted with gates at various depths. Others
have an adjustable suction pipe attached to a floating raft to draw water from the
reservoir or lake at different levels. Water may be drawn at or near the surface when
the deeper water has a bad taste or odor from decomposing organic matter. Water at
an intermediate depth is used when microorganisms are prevalent near the surface.
The lower depth can provide cooler water in the summer. Experience will tell the
operator which water intake depth yields the best water.
Intake stoppage may, in most cases, be cleared by backflushing the
intake conduit or pipeline. When danger of intake stoppage exists, keep backflushing
equipment readily available. Damage by surface ice can be prevented by locating an
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