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* *: 6 6.3 DRYSTONE MASONRY STRUCTURES
190
WATER USE
MANAGEMENT
The lack of rainfall and high temperatures
in summer, characteristic of
the island's Mediterranean climate,
made it necessary to build ingenious
drystone masonry structures to store
rainwater or surface runoff, and also
to collect underground water produced
by the infiltration of the limestone
and quaternary deposits which make
up a large part of Majorca.
In terms of water extraction, wells
and waterwheels are frequently found
on the coastal plains or in the bottoms
of valleys where the water table layer
is not so deep down. In the mountainous
areas, especially in the Serra de
Tramuntana, natural springs and other
sources where permeable and impermeable
rock meet were taken advantage
of and adapted, the water being
collected and drawn to the surface by
gravity along drystone galleries
(mines or underground passages).
From a strictly building point of
view, the simplest and most common
types of wells are circular walled
holes with their entrances at ground
level.
To stop people falling in they were
covered with branches or surrounded
by a pareto or low wall (call or neck).
Less frequently they are elliptical or
square-shaped. The most elaborate
ones have a capelleta (small dome) to
protect the water and to prevent evaporation
or are built into a terrace wall.
Water is extracted manually using a
bucket tied to a rope or with the help
of a wooden or iron pulley.
Waterwheels are wells that are normally
rectangular with rounded corners
and a system of gears to withdraw
the water which was traditionally
worked by animal power. These constructions,
found in places where the
water table is not very deep, often
have drystone masonry holes, necks
and bases or mounds and may also
have an underground passage for
access into the well.
Natural springs found at the foot of a
terrace wall were often adapted using
drystone masonry capelletes and
more complex systems were used for
underground passage springs, which
consisted of digging out underground
galleries down to the water table to
withdraw water.
Underground passage springs
usually have drystone masonry faced
entrances, passages and openings.
The features of the place where
water is extracted together and the
use that is made of it determined the
setting up of a water supply system
involving irrigation channels, cisterns
and small reservoirs.
Likewise the range of uses (crops,
livestock, manufacturing, human consumption)
and the fact that water is a
scarce resource have, throughout the
island's history, led to the creation of
public exploitation systems for
springs and wells by groups of users.
In the municipalities in which the presence
of water resources has made it
possible to establish complex
systems for using springs (Banyalbufar,
Soller, Alaro, etc.) , irrigation farmer
associations or unions were founded
to control the irrigation rights of each
farmer, to lay down regulations for the
cleaning of irrigation channels, to
impose sanctions on offenders, etc.
Reservoirs that were partly or completely
built of drystone masonry were
used to collect rainwater or surface
runoff. Cisterns were often built in
houses that collected water from the
roof; to prevent leakage the hole itself
was not a dry stone structure but its
call and capelleta quite often were.
Some cisterns were built into terrace
walls to collect the water that flowed
into them.