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In the opinion of Protonique experts, the use of ground water in Cyprus
has become dangerously anarchic and requires the severe application of
existing and new regulations. Even under the best conditions, the
aquifers will require a decade or more of rainy winters to re-establish
themselves with fresh water to a normal water level. In reality, it is
possible that this wonderful resource will be lost for ever in some places
through over-exploitation.
There are several kinds of water table and aquifer. The two mountain
systems on the island feed them in different manners. The accompanying
geological map is an approximation with minimal detail. The Pentadaktylos
(Kyrenia) mountains are essentially permeable
sedimentary rocks, largely
limestones and sandstones of many types and ages, raised by seismic
activity. Much of the rainfall is absorbed into the rock and can flow
downhill for as far as the rock remains porous or meets a fault line which
allows the water to move to another porous layer. On the southern slopes,
these porous layers extend to many kilometres south of the foothills into
the Mesaoria and provide water to, for example, the Lefkosia region. There
are several
phreatic aquifers, allowing water to be
pumped up from different levels. There is practically no
vadose water in this region. The water quality is generally fairly
hard, as it contains dissolved
calcium salts from the limestone.
In many places, sedimentary rocks are overlaid by geologically-recent
alluvial deposits brought down by
ancient river systems flowing from the Troodos massif. The most important
one covers much of the Eastern half of the Mesaoria, north-west of
Famagusta, as far as south-west of Lefkosia, but there are other ones round
Morphou and Larnaka, the latter stretching along the littoral to Zygi. The
Akrotiri peninsula is almost entirely alluvial. Other patches exist in many
other regions. This alluvium consists essentially of clays and marl which
can form an imperveous cap over the underlying rock formations.
The Troodos mountain massif is essentially older, non-porous,
metamorphosed
igneous
(volcanic) rock. Rain water is absorbed into the structure by a honeycomb of
seismic faults and other structural cracks, some of them less than a
millimetre wide. Gravitation forces the water downwards, but there is no
true water table or aquifer. This water is essentially vadose and is
relatively soft as there is little sedimentary calcic rock, but with a
variety of dissolved mineral salts depending on the rock structure through
which it passes. When such vadose water is led to the surface, this forms a
spring, such as is exploited for the bottling of mineral water. The pressure
of hundreds of metres of water at higher altitudes ensures an almost
constant perennial flow from such sources, in many cases. Most of the water
flows out of the volcanic region and, through fault lines, enters into more
porous rock in the Mesaoria and coastal plains, frequently below sea level
and eventually into the sea. Normally, the hydrostatic pressure of the fresh
water prevents it becoming contaminated by sea water, as the flow is towards
the sea. This passage through porous rock, sandstone or limestone, is
phreatic in nature.
In the plains, much water is pumped out of the phreatic aquifers from
boreholes and wells and this is done to such an extent that some aquifers
are being totally dried out and the water tables are dropping in practically
all regions. In the Troodos massif region and in the foothills, such as
towards Stavrovouni, the ground water supply is less reliable as a well or
borehole would need to penetrate a water-carrying crack or fault to fill.
This would depend to some extent on chance but a
hydrological
survey could plot the major water-carrying fissures. Some areas have
virtually no ground water down to the limit of normal borehole-drilling
capacity, whereas a seemingly unlimited supply may sometimes be found just a
few tens of metres away. Some villages (e.g. Pyrga) in this region have very
adequate water supplies from boreholes, where neighbouring ones (e.g.
Mosfiloti) have practically none. A borehole has recently been drilled just
above Mosfiloti, but it is not yet being exploited (July 2008). Worse, as
the water tables drop in coastal regions, the hydrostatic pressure falls and
sea water is infiltrating into aquifers which are exploited, especially for
agriculture. This is especially serious in the south-eastern part of the
island in the triangle circumscribed by Cape Greco, Dhekelia and Famagusta,
where well water is becoming brackish. An aquifer contaminated by sea water
could remain unusable for decades, even if it is restored to full freshwater
flow after adequate rainfall. This is partially because of the time lag
between rain falling in the mountains and reaching the lower levels and
partially because flushing the salt out from contaminated aquifers is a
process of continuously successive dilutions. Other regions, including the
market gardens around Maroni, with important tomato and cucumber production,
are beginning to experience similar problems.
With little doubt, it is the conservation of ground water that requires
to be addressed the most urgently. New regulations must be implemented based
on hydrological surveys, forbidding aggregate water to be pumped out of
aquifers at a faster rate than water is arriving. This will be an expensive
operation and may even close down some supplies of water. It is without any
doubt that this is essential if the future economy of the island is to
survive, particularly in the agricultural and related sectors.
The first thing that must be realised by everyone is that water pumped up
from under the ground is not an unlimited free gift from heaven. Every drop
wasted in one place may be depriving other users downstream of what they
need for economical survival. The implication here is that every well and
borehole in the country must be catalogued along with the water source that
is being exploited by it, derived from a precise hydrological survey.
However, it is not sufficient for the quantity of water extracted to be
reduced to what is arriving, the depleted aquifers must be allowed to
regenerate themselves. This can be done by pumping out only, say, half of
the water that arrives. Even so, it would probably take at least a decade of
normally wet winters before all the aquifers would be restored to a
more-or-less normal situation.
It is recommended that existing subsidies on borehole drilling be stopped
with immediate effect and possibly replaced by a taxation on new drillings.
A precise and complete hydrological survey will have the advantage that
currently unexploited sources may be discovered. These may be from aquifers
underlying existing ones but separated from them by a cap of impervious
rock. It is possible that large quantities of new water at depths of between
500 and 1,000 metres may be found.
The implication of the foregoing is that owners and users of wells and
boreholes would need to be severely rationed as to the quantity of water
they would be permitted to extract, derived from the data established by the
hydrological survey and their probable requirements. Metering of each source
would therefore need to become a legal obligation. We suggest that
extraction beyond the annual limit laid down would best be discouraged by
the payment of charges on a sliding scale, at an increasingly swingeing rate
according to the extra extracted volume. It is clear that this kind of
measure would not be popular, but Protonique experts are unanimous that it
is only by stringent measures that the situation can be resolved in the
medium term.
The extractable ration under such a regime could be adjusted annually,
according to the rainfall. On a more controversial note, there is the
question to be resolved as to whether certain classes of users require a
priority supply which would be detrimental to other classes. For example, it
may be felt that private individuals who use well water for their gardens
should obtain proportionally less than agricultural exploitations. This
would be logical, but there would be two disadvantages:
- the psychological impact of restricting water to the extent that
their gardens would suffer unduly would not be favourable to the
implementation of such plans;
- a minority of individuals would be inclined to use municipal
potable water for their gardens to
make up the shortfall.
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