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Dear Sir,

I believe that the criticisms of the local water authority (EMAYA) made in “Viewpoint” in the 6th of April, 2002 issue of the Majorca Daily Bulletin are unfair. These made the water authority look incompetent while these ignore the technical problems and economic considerations of the problems specified.

1. Leaks in the water distribution system is a problem found in all areas with old pipes in all older cities. Large leaks are easy to detect and repair while small leaks, particularly in water pipes laid underground, beneath concrete and asphalt pavements are very difficult to pinpoint. And, it is the total of many small leaks that cause the bulk of the losses. It is uneconomic to dig up large portions of a street to repair one or two small leaks. What should be done and is being done is to inspect the water pipes, sector by sector, particularly when streets have to be dug up for expansions or other installations and this is so also done. This, of course, takes time, but it is the most economical way of solving the problem.

2. The maximum utilisation of the island's rainfall could be an ideal situation but it is an impossible dream because of the technical and economic considerations. In rural areas with porous soils, rain water seeps through the ground to form part of the island's underground water reserves in its water bearing strata. From there it is pumped up for the use on the surface, previously by windmills which dot the farm areas of the island and now, mostly by motor driven pumps. It is only in the few times a year when the rate of rainfall exceeds the ability of the soil to absorb it that the rainwater over flows into the “torrentes,” which are in effect natural drainage canals. In rocky areas and where the soil is not porous, this rainwater flows into the torrentes which then lead it to the sea. The flow of water in the torrentes depends on the rainfall. On the average in Majorca, you may have some seven to fourteen days (not necessarily consecutive) of heavy rain a year, some thirty to forty-five days of moderate rains a year, and light to no rain for the balance of the 365 days a year. Thus, you can expect a heavy flow in the torrentes during seven to fourteen days a year, moderate flow for at most forty five days a year, and very little or no flow for the rest of the year. To recover this water effectively, you would have to design systems for each torrente for a maximum daily flow. This would involve dams, pumping stations, pipelines and satellite reservoirs which would operate at a capacity for only seven to fourteen days a year, and would probably not operate for ten months or more a year. Any engineer can tell that the cost of the water recovered would be very high, perhaps prohibitive. Thus, the cost of the water recoverable from the torrentes, including the Riera, is not attractive, particularly when less expensive alternative systems are now available.

3. The phenomenal increase in tourism and the rapid growth in population during the last two decades in Majorca increased the demand for water beyond anything that could have been imagined. Not only do people on holiday use more water per person per day than residents, but such amenities such as swimming pools, golf courses and air conditioning (large air conditioning installations use water cooling towers to cool the air) all contribute to this increase in demand and it soon became evident that the island's dependence on rain for its water supply could not meet the demand for water. Alternative sources had to be found and the local water authorities embarked on solving this problem. Bringing water from the mainland was tried and found to be very expensive. Fortunately, the development of the Reserve Osmosis process by which salt water is pumped through special membranes which let the water through while retaining the salt produced the solution. This process is energy intensive, but for an island like Majorca, it could provide water to increment the traditional supply at an affordable cost. Yes, there were delays in building the desalination plants and there were start-up problems normal of such plants, but these desalination plants are now providing the additional water to ensure an adequate supply and by averaging the cost of the water supplied by rain and that supplied by the desalination plants, the cost of water in Majorca, while higher than that in the Peninsula, is still affordable. However, as any incremental production of water for export would have to come from desalination plants, the idea of exporting water from Majorca is economically impossible.

4. I am in no way connected with the local water authority, but I am an engineer with forty-five years of experience in the design, construction and operation of large chemical plants, which included their water supply installations. In my retirement, I have made it a point to study such problems as the water supply and waste disposal in Majorca. My conclusion is that despite delays and having to face abnormally dry weather during the last few years, the local water authority EMAYA has done a very good job in solving Majorca's water supply problems. Of course, there will always be some leaks in the delivery system. As there is no such thing as a 100% leak-proof system, and some localised problems have to be expected as again, there is no such thing as 100% fool-proof installation, but let us give them credit where credit is due.

Yours sincerely,

Pedro Picornell, Palma.