I would like to congratulate you on your Inside Science 'Water from the ground' (16 February). As a farmer, this has at last enabled me to understand why a spring line should be near the top of the hill and how the water table, and hence the flow of ditches, varies depending onthe season.
More importantly, the report demonstrates how it usually takes many years for water to find its way down through the soil and the unsaturated zone to the saturated zone of an aquifer. Farmers have been applying increasing quantities of fertiliser which is only now beginning to result in nitrate pollution of the water from aquifers. Evidently, we are sitting on a time bomb. One would have anticipated that the Ministry of Agriculture, Fisheries and Food had sufficient technical knowledge to foresee the resulting pollution problems, and advise against using high input, high profit systems.
A. J. ...
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