§ Mr. Martyn Jones
To ask the Secretary of State for the Environment what assessment he has made of changes in the(a) source and (b) quantities of nitrates in the River Thames over the last six years; and if he will make a statement.
§ Mr. Clappison
Nitrate concentrations in surface waters, including the River Thames, and in groundwaters are monitored by the Environment Agency as required by various European directives. The resulting data enable us to identify, and review as necessary, when action is needed to comply with the requirements of these734W directives in relation to nitrate pollution. For example, in the context of the nitrate directive, assessment of 1992 data on nitrate concentrations in surface waters led to the designation of nitrate vulnerable zones covering nine river catchments. The River Thames did not meet the criteria for designation in the first round. We shall be reviewing the vulnerable zone designations in 1997, as required by the directive, based on monitoring data currently being collected by the agency and available on their public registers in the usual way. The latest data on trends in river nitrate concentrations in the Thames region and in other parts of Great Britain are presented in the Department's 1996 Digest of Environmental Statistics, No. 18.