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Natural Resources

Practically all our natural water is derived from precipitation, which we shall call rain water even though it is partially in the form of snow in the mountains and, to a much lesser extent, cloud, mist and dew. A popular belief holds that the wells in the Mesaoria are fed from water which comes from the Turkish Taurus mountains, but there is no scientific confirmation of this idea, which is geologically highly improbable.

Rain Water

The average annual rainfall in Cyprus is about 48 cm, with a geographical distribution of most in the Troodos massif, in the Kyrenia mountains and least in the Western Mesaoria (see map). It should be noted that the map and the table of the rainfall in the major towns diverge slightly, as they do not cover the same period. This represents a total annual precipitation of about 4,500,000,000 tonnes (cubic metres) or almost 6,500 tonnes per inhabitant. In reality, the water consumption per inhabitant, including all usage, is less than 300 tonnes per year or about 4½ per cent of the total precipitation. If we are short of water, it means that over 95% or our natural resource goes to waste. By careful conservation measures, we should be able to improve this ratio considerably.

The above graph shows the rainfall between October and April of each year in this century (red line) and the 5 year moving average (dark blue line). It can be seen that the rainfall is quite variable, ranging from just over 200 mm to just under 800 mm in extreme years. Over the winters of 1995/6, 1996/7 and 1997/8, the rainfall has been consistently about 400 mm or about 15% less than average. This does not explain why the dams have dropped to 90% less than maximum: the "drought" has been an excuse for an increased and profligate use and wastage of water. The rainfall situation was far worse in the early 1970s, but there was no real water shortage, then. At the time of writing, the winter of 1998/9 is still in course, but it would appear likely that the rainfall will be somewhat over-average, probably between 500 and 600 mm. This will surely be insufficient to fill the dams to more than a few percent more than they were a year earlier.

It is interesting to note that the 5-year average rainfall is consistently falling over time and has dropped by about 100 mm since the start of the century. It is impossible to draw conclusions as to the cause or causes, but it seems likely that climate change is a major contributory factor. The cause of theis change is controversial but there would seem to be increasing evidence, although no scentific proof, as yet, that it is due, at least partially, by man-made activities, notably fossil fuel combustion, methane production and the use of fluorocarbons. These emit gases which capture the infra-red radiation from the earth's surface and cause "global warming". The following graph shows the average temperature in Cyprus from the beginning of the century (red line) and the 5-year moving average (dark blue line). It can be clearly seen that there has been a temperature rise averaging  about 1°C over the century, although there is no correlation between the temperature and rainfall on a yearly basis. This is the difference between weather and climate.

Conservation

Without doubt, there is little likelihood of being able to increase significantly the capture of rain by more large dams. The major valleys suitable for this are already exploited and further development would be environmentally and economically undesirable. Large numbers of small dams (surface areas of water from 1,000 m² to 10,000 m²) could be constructed on seasonal water courses, often in small gullies up to 20 m deep which are unsuitable for agriculture or other development. An average one could be constructed to hold 75,000 tonnes. This seems small but, if it is exploited in late spring to near-dryness, it would save so much water from being drawn off the major dams or from ground water aquifers. This volume is typically that consumed by a village of about 1,000 inhabitants for household use in a year. The dams could be of earth construction, reinforced by boulders and a concrete armature to prevent seismic collapse due to liquescence of the soil under stress, with a typical constructional volume of 5,000 m³ of earth, mostly removed from the flooded part. The most important point to consider is that no single dam should retain more than about 25 or 30 per cent of the inflow at any time and no watercourse should be restricted by more than 50 per cent of the natural water flow at any given place. This would ensure that the impact on the downstream natural ecosystem would be small. Automatic flow-control would be desirable. The water quality may be potable in favourable areas, but may be suitable only for agricultural irrigation in regions where there are free toxic metallic ions or microorganism contamination from upstream.

There are several other ways that rain water may be conserved for some uses. Over 25,000,000 tonnes of rain fall on metalled roads each year. If just half of this could be collected into reservoirs, the volume would be equivalent to almost the total potable water requirements of Lefkosia in a whole year. It is emphasised that such water, untreated, would not be potable, being polluted with asphalt, oil drips, rubber decomposition products, organic particles from diesel exhausts and, above all, a small quantity of lead from petrol engine exhausts, but it could be easily and cheaply rendered suitable for irrigation. As root absorption of water is by osmosis, the weak lead salts would not be absorbed significantly into edible crops. Such water would not be suitable for pisciculture as the lead may enter into phytoplankton which would be at the low end of a food chain, entering via fish into humans. No significant harm would result from the lead entering the sea, as the dilution would be sufficient that marine life would be unaffected.

Another way that rain could be conserved would be from the roofs of houses. A typical modern villa may have a roof area of 100 m². With the average rainfall figure of 48 cm, the water falling onto it each year would therefore be 48 tonnes. It would be possible to collect at least 35 tonnes of this, which would suffice for at least half the annual requirements for watering a large (say, 1000 m²) garden. The cost of this would be the guttering and downpiping, in PVC or metal, plus an underground reservoir and a pump. The reservoir could be in an excavated hole of, say, 4 m by 5 m by 2 m deep, lined with 2 mm thick welded polyethylene sheeting with a 10 cm reinforced concrete cap, over which 30 cm of soil could be placed. If such a construction were to become standard in new property, the extra cost would be typically about £500. If it saved 35 tonnes per water per year, it would take about 15 years to amortise, not counting interest on the investment, with water at an indicative price of £1/tonne. This would therefore not be viable, if looked at from a strictly economic point of view, but water, if it is lacking, has no price. The government may care to consider the feasibility of offering small subsidies for such constructions to reduce the amortisation period from 15 to 10 years, say £150 per house with 100 m² of roof and 35 tonnes of approved reservoir capacity (pro rata for other sizes), or even to render such conservation as required on new constructions, in an analogue manner to anti-seismic measures. The cost of adding this to existing property would be higher and more difficult, but not impossible to implement. This may also be combined with a grey water system (see later), reducing the overall cost of both.

With new multi-dwelling property developments, the situation would be much more favourable, in that all roof and service road water runoff could be piped to a central reservoir close to the lowest point. It could then be pumped back to the individual houses via a second plastic water pipe system. Amortisation and equitable distribution could be assured by metering the individual consumptions. As a rough estimation, this would cost about 20 per cent less than individual construction for a 20-house development and would conserve almost twice as much water, probably sufficient for the garden requirements of the whole estate, because of the captured road runoff. This would be economically viable for the investment, with a write-off period of 7-8 years, again not counting interest.

Surface Water

Surface water is defined as that flowing in perennial and seasonal water courses and natural springs and fresh water marshes, lakes and ponds, but excluding existing dams. If any further action is taken to conserve surface water for human activities, care must be taken not to upset local ecosystems which may already be stretched to their limit.

Conservation

Little further can be done to conserve surface water, other than a multitude of small dams mentioned above.

Ground Water

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. 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.

Conservation

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:

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