| Development of Springs and
Seepages
In hilly areas with good rainfall, like in the northern
talukas of Thana District, it is possible
to find a number of small springs and seepages which can
be developed for the water
supply of people and animals living close by. Often these
precious water sources
disappear in loose material at only a few meters from the
point where they surface.
There are two main type of springs in the hilly area of
northern Thana District: the contact
spring and the gravity spring.
The contact spring emerges at the contact of a
water-bearing permeable layer or fractured
zone with an impervious rock. In most cases this type of
spring is located on a steep slope,
often non easily accessible. Spring water often
disappears in gravel and loose material
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Fig.
7 - Spring emerging on slope
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| Fig. 8 - Spring
emerging from seepage |
after a short distance from the emerging point.
The appropriate spring box designs for
capturing these two types of springs are shown in Fig. 7
and fig. 8, ref. 11. Water from
contact springs can be piped and delivered in low-lying
areas for the use of people and
animals.
The gravity spring is generally located at the bottom of
a slope and is characterised by the
presence of green vegetation, or marked by a wet area; it
is defined also as underground
spring, and represents the slow discharge of rainwater
infiltrated mainly in talus deposits.
This spring is easily accessible to people and animals
who often dig down into the seepage
area in an attempt to increase their discharge.
In recent years, small seepages have been rudimentarily
tapped in Thana District by
shallow, small diameter hand-dug wells, called
“spring wells”. In most cases they supply
seasonal water; their depth generally does not exceed 2.5
m; trenches or collector channels
are not constructed to increase their yield. To improve
drainage and seepage discharge,
the appropriate structure is shown in fig. 9 & 10.
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Fig.
9 and 10 - Seepage and spring box development
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Properly designed spring boxes could, in some
cases, improve the severe water shortages
which characterise the majority of the villages located
in hilly areas.
The identification of springs and seepages can be done
with the help of local people and
from aerial photo interpretation. A complete inventory of
springs and seepages in the hilly
areas should be carried out for future use.
The development of seepage water from the base of walls
and bunds delimiting rice plots
in low lying land could also improve the water scarcity
problem of many villages.
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