The Borehole latrine is the forerunner of the
non-service type of latrines in this country. It was first introduced by the
Rockefeller foundation during 1930's in campaigns of hookworm control. The
latrine consists of the circular hole 30 to 40 cm (12-16 in.) in diameter, dug
vertically into the ground to a depth of 4 to 8 m (13-26 ft.), most commonly 6
m (20 ft.). A special equipment known as the auger is required to dig a bore
hole. In loose and sandy soils, the hole is lined with bamboo matting or
earthen-ware rings to prevent caving in of the soil. A concrete squatting plate
with a central opening and foot rests is placed over the hole. A suitable
enclosure is put up to provide privacy. For a family of 5 or 6 people, a bore
hole of the above description serves well for over a year. The borehole is
essentially a family type of installation and is not recommended as a
public convenience because of its small capacity. When the contest of the bore
hole reach within 50 cm (20 in) of the ground level, the squatting plate is
removed and the hole is closed with earth. A new hole is dug and similarly
used. The night soil undergoes purification by anaerobic digestion
and is eventually converted into a harmless mass.
The amount of sludge that accumulates has been estimated to amount to 2.1 to 7.3 cubic feet per. 1000 users’ days.
The merits of a bore hole latrine are:
- There is no need for the services of a sweeper
for daily removal of night soil.
- The pit is dark and unsuitable for fly breeding,
- If located 15m (50ft) away from a source of
water pollution. In spite of these merits, borehole latrines are not
considered a very suitable type of latrine today.
The reason is :
1.
The bore hole
fills up rapidly because of its small capacity,
2.
A special
equipment, the auger is required for its construction which may not be readily
available
3.
In many places the
subsoil water is high and the soil loose with the result it may be difficult it
dig a hole deeper than 3m (10ft) . The borehole latrine is therefore not very
much in use today. It has been superseded by better innovations.
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