HC Deb 12 December 2002 vol 396 cc447-9W
Norman Baker

To ask the Secretary of State for Environment, Food and Rural Affairs what average level of nitrates there has been(a) within river courses and (b) in drinking water in the United Kingdom in each year since 1990, broken down by river course, type and region. [86407]

Mr. Morley

Responsibility for Scotland and Wales falls to the relevant devolved administrations.

(a) Nitrate levels in river courses in England and Northern Ireland

England: The Environment Agency monitors nitrate levels in rivers in England as part of the General Quality Assessment (GQA) network. Average annual nitrate provided by the Soil Association. There are no retail prices available.

levels are published each year and regional breakdowns are available from the Environment Agency. Detailed data can be obtained via www.environmentagency.gov.uk. The recent Environment Agency publication "Rivers and Estuaries: a decade of improvement" contains details of the latest GQA nutrient monitoring data. This is available from the Environment Agency on 08459 333111 and from www.environment-agency.gov.uk/yourenv/eff/water/213902/river_qual/24904/?lang=_e®ion.

Northern Ireland: Since the early 1990s the Department for Environment's Agency the Environment and Heritage Service has monitored nitrate levels on a monthly basis at approximately 260 river sites throughout Northern Ireland. In the period 1990 to 2001, a total of 45,109 samples have been analysed for nitrate and 13 samples (0.03 per cent.) have failed the 50mg NO3/L standard laid down in the EC Nitrates Directive (91/676/EEC).

(b) Nitrate levels in drinking water in England and Northern Ireland

The Water Supply (Water Quality) Regulations 1989 set a maximum standard for nitrate in drinking water at 50 milligrams per litre. This standard remains the same within the Water Supply (Water Quality) Regulations 2000, which come into force on 25 December 2003.

England: It is not possible to give a breakdown of nitrate in drinking water by river course and region. The percentage of tests which failed to meet the nitrate standard within England and Wales has fallen from 2.8 in 1990 to 0.08 in 2000. In 2001 there was a small rise in the percentage of tests failing to 0.38. This is linked to the occurrence of nitrate being found in groundwater supplies, as a result of pollution from long term agricultural runoff.

The table shows the data in each of the years.

Year Percentage contravening the standard
1990 2.8
1991 2.8
1992 1.9
1993 0.9
1994 0.8
1995 0.4
1996 0.1
1997 0.04
1998 0.05
1999 0.06
2000 0.08
2001 0.38

Where there has been a contravention of a standard which is not trivial and is likely to recur, the Drinking Water inspectorate requires the water company concerned to give a legally binding undertaking to take remedial action to achieve compliance. In the case of nitrate the simplest option is to blend the high nitrate containing water with low nitrate containing water, if available. Otherwise more complex treatment is needed.

Northern Ireland: Between 1 October 1994 (when Northern Ireland's Water Quality Regulations came into force) and the end of 2001 the nitrate standard in drinking water supplies was contravened on 16 occasions out of a total of 5,873 tests. The number and percentage of tests failing in each year is given in the following table.

The contraventions in 1998 occurred in one water supply zone. Blending action was taken to achieve compliance thereafter.

Year Number of tests Percentage contravening the standard
1995 1,216 0.00
1996 851 0.12
1997 809 0.12
1998 746 1.88
1999 777 0.00
2000 732 0.00
2001 742 0.00