§ Mr. MeacherTo ask the Secretary of State for the Environment if he will list how many miles of rivers have been downgraded from each grade to the one below, and to a lower grade in each region for each year since 1980.
§ Mr. HowardChanges in the lengths of rivers and canals in each quality class recorded between the 1980 and 1985 river quality surveys are shown, by water authority, in appendix V to the report of the 1985 river quality survey of England and Wales. A copy of the report has been placed in the Library of the House.
The 1985 river quality survey showed that rivers in England and Wales continued to be of a high quality with 90 per cent. assessed as of good or fair quality. For those lengths of rivers surveyed in both 1980 and 1985, a total of 4,490 km (12 per cent.) improved in quality, while 5,440 km (14 per cent.) were downgraded. However, because of differences in the methods used between authorities and changes between surveys, it is uncertain whether this small apparent net deterioration represents a real change. But it did appear that the hitherto upward trend of improvements in river quality had, at least for the time being, been checked. Details of changes between quality classes recorded in individual years between 1980 and 1985 are not held by the Department.
The lengths of rivers and canals recorded in each class in the years 1985–87 have been published in the "Digest of Environmental Protection and Water Statistics" (No. 11, 1988) a copy of which has been placed in the Library. This information indicates that since 1985 there has been some increase in the length of good and fair quality rivers and a reduction in the length of poor and bad quality rivers. The improving trend thus appears to have been resumed. However these results are not directly comparable with the results from the river quality survey because they are based on more limited surveys carried out by the water authorities.
The next comprehensive river quality survey is planned to take place in 1990.