V - ResearchSpace

413
thirteen boreholes were fitted with automatic water
stage recorders.
At about the same time regular sam-
pIing of water from unused and pumped boreholes was
commenced for tritium and chemical analysis.
GROUND-WATER LEVELS, STORAGE AND REPLENISHMENT
No aquifer evaluation tests have been carried out
in Serowe because of the continuous pumping taking place
at present to keep the village supplied with water. If,
however, the values for the coefficient of storage ob-
tained for the same aquifer at Orapa are applied to Serowe,
then for every square kilometer of aquifer, a total of
6 3 63.
between 5 x 10 m and 26 x 10 m of water wlll be present
in storage.
A study of the hydrographs of all boreholes in
Serowe shows that marked seasonal fluctuations take
place which directly reflect the amount of recharge that
has taken place. In the vicinity of boreholes 670 and
1510 (Figs. 93, 95) little recharge took place in the
1967/6 8 season and again jn the 1969/70 season. In the
1966/67, 1968/69 and 1971/72 seasons major recharge took
place, while less recharge occurred in the 1970/71 season.
These fluctuations are generally of the order of three to
five metres but, in the case of borehole 670 (Fig. 93),
may be up to 60 metres.
Borehole 489 (Fig 96) is a low yielding borehole
sited in the lower Cave Sandstone stage and consequently
penetrated less than 30m of sandstone before going into