dig well and pumps

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Until recent centuries, all artificial wells were pumpless dug wells of
varying degrees of formality. Their indispensability has produced numerous
literary references, literal and figurative, to them, including the Christian
Bible story of Jesus meeting a woman at Jacob's well (John 4:6) and the "Ding
Dong Bell" nursery rhyme about a cat in a well.

Such primitive dug wells were excavations with diameters large enough to
accommodate men with shovels digging down to below the water table. swimming pool pump They
can be lined with laid stones or brick; extending this lining into a wall around
the well presumably served to reduce both contamination and injuries by falling
into the well. A more modern method called caissoning uses reinforced concrete
or plain concrete pre-cast well rings that are lowered into the hole. A well
digging team digs under a cutting ring and the well column slowly sinks into the
aquifer,whilst protecting the well digging team.

Hand dug wells provide a cheap and low-tech solution to accessing groundwater
in rural locations, with a high degree of community participation. Hand dug
wells have been successfully excavated to 60m. Hand dug wells are cheap and low
tech (compared to drilling) as they use mostly hand labour for construction.
Hand dug wells have low operational and maintenance costs. Even if the hand pump
is broken, water can still be extracted. In many cases, hand dug wells are
similar to traditional abstraction methods and are readily accepted by the host
community. jet pump The
construction of hand dug wells can incorporate a high degree of community
participation (e.g. pre-fabrication of concrete rings). Hand dug wells can be
easily deepened, if the ground water level drops, by telescoping the lining
further down into the aquifer. The yield of existing hand dug wells may be
improved by deepening or introducing vertical tunnels or perforated pipes.

Hand dug wells are not suited to hard ground formations and take time to dig
and line. deep well pump Construction of hand dug wells can be dangerous due to collapsing
soils, falling objects and asphyxiation. Hand dug well construction generally
requires the use of a trained well construction team. Construction of hand dug
wells can require large capital costs for equipment such as concrete ring
moulds, heavy lifting equipment, well shaft formwork, motorized de-watering
pumps, and fuel. sewage pump Since
most hand dug wells exploit shallow aquifers, the well may be susceptible to
yield fluctuations and possible surface contamination.

Safety during hand dug well construction is paramount due to the risk of
collapse, submersible pump falling objects and suffocation from exhaust fumes from dewatering pumps.