This paper reviews the processes by which groundwater and surface water flows are polluted by nitrates on the Island of Jersey in the English Channel. It is shown that the primary cause of such pollution is the use of nitrate fertilizers by the Island's farmers. The activities of the major government institutions involved in reducing nitrate pollution are described and the costs of such management are assessed. The instruments deployed are regulatory, infrastructural, and educational; in contrast, economic instruments have not been deployed. The article then moves on to consider the benefits of pollution reduction in respect of enhanced environmental quality and improved human health. In conclusion, it is suggested that the standard for the nitrate content of drinking water, based on European Community legislation of 1980, was set at a level for which no human health benefits have been demonstrated but at substantial costs to the citizens of Jersey. This “cost without benefit” hypothesis is applicable to many other countries with respect to nitrate pollution management.