inadvertent discharge under pressure from a chamber
had a rather violent reversal of water flow
in toilets on adjacent sanitary lines. This
must be prevented.
b. Storm Drain. Discharge into a storm drain may overload the lines.
The authority responsible for operating the storm sewer system should be
WATER TREATMENT. The large volume of fresh water must be treated
initially and repeatedly during the mission to reduce turbidity and control
TURBIDITY. When water is collected in large volumes as required in wet
pots, the actual turbidity usually exceeds the level that can be tolerated
the mission. Experience has shown that the only practical method of reducing
turbidity is filtration which will also remove contaminants that get into the
water when the system is in use. Filtration must be a continuing process on
the large volume of water so the filters must have very generous capacities
and be easily serviced.
It is possible to arrange the chamber system so that a low-cost low-pressure
filter will be used only when the chamber is not pressurized. However, the
limitations that this arrangement places on the chamber will usually outweigh
the one-time benefit of low initial cost. To reduce the initial cost,
filters have been installed inside the wet pot, below the floor, but they
were discarded because they were difficult and inconvenient to service. A
satisfactory filtration system, shown in Figure 7-1, has a pump, filter,
NAVFAC DM-5, Civil Engineering (Reference (1)), provides information for the
selection of filtration equipment.
CHEMICAL CONTENT. Virtually all local water supplies contain chlorine
and salts of fluorine. There is no need for the designer to consider special
equipment or procedures to protect the wet pot occupants and equipment from
the effects of these chemicals. Experience has shown that by the time the
water has reached an acceptable level of clarity, the undesirable chemical
content has been reduced to an acceptable level.