c. Deep Pit Latrines. The deep pit latrine is used with a latrine box placed over
it. The standard type box provides four seats and is 8 feet long and 2 1/2 feet wide at
the base. A unit of 100 men requires 8 feet of latrine space, or one 4-seat latrine box
(see Figure 3-3). The holes should be covered with flyproof, self-closing lids. All cracks
should be flyproofed with strips of wood or tin nailed over them. A metal deflector
should be placed inside the front of the box to prevent urine from soaking into the wood.
The deflector may be made with flattened cans.
Figure 3-3. Deep pit latrine.
(1) Construction. The pit is dug 2 feet wide and 7 1/2 feet long. This will
give the latrine box 3 inches of support on all sides. The depth of the pit will depend on
the estimated length of time the latrine is to be used. As a rough guide, a depth of one
foot is allowed for each week of estimated use, plus one foot of depth for the dirt cover,
when closed. Generally, it is not desirable to dig the pit more than 6 feet deep because
the walls might cave in. Rock or high ground water levels often limit the depth of the pit.
In some types of soil, a support of planking or other material for the sides may be
necessary to prevent wall cave-ins. Earth should be packed tightly around the bottom
edges of the box so as to seal any openings through which flies might gain entrance.
(2) Sanitation. In order to prevent flybreeding (deposit and hatching of
eggs) in the pit and to reduce odors, keep the latrine box clean, the seat lids closed, and
the cracks sealed. Also, a good fly control program must be maintained in the area.
The use of Iime in the pit or the burning out of the pit contents is not effective for fly or
odor control and should not be used. The box and the seats of the latrine should be
scrubbed daily with soap and water. When a unit leaves the area or when deep pit