Lead in Drinking Water
The Regulatory Position in England and Wales
The standards specifying maximum concentrations of lead in public drinking water supplies are set out in the Water Supply (Water Quality) Regulations 2000 for England, and in Wales by the Water Supply (Water Quality) Regulations 2001. These Regulations, which came into force on 25 December 2003, specify an interim standard for lead of 25 µg/l to be achieved by 25 December 2003 and a final standard of 10 µg/l to be achieved by 25 December 2013. These more stringent standards for lead transpose the requirements of the EC Drinking Water Directive (98/83/EC). Previous to December 2003, the Water Supply (Water Quality) Regulations 1989 set a standard for lead of a maximum of 50 µg/l in any sample from a consumers' drinking water tap.
To achieve the interim standard, the Drinking Water Inspectorate put in place Regulatory Programmes of Work under Regulation 41 of the 2000/2002 Regulations. These programmes required water companies to:
- install additional treatment at water treatment works to reduce the plumbosolvency of water supplied at the tap;
- optimize the treatment measures installed;
- carry out opportunistic lead pipe replacement in the distribution system;
- carry out strategic lead pipe replacement in the distribution system to meet 25µg/l; and
- carry out strategic lead pipe replacement in the distribution system to meet 10µg/l.
Funding for the Regulatory Programmes of Work for additional treatment facilities at treatment works was provided for in the 1999 Periodic Review of Prices for the years 2000 - 2005 (Asset Management Period 3 - AMP3). Water companies were also allowed some financial provision within this AMP3 period to make a start on Regulatory Programmes of Work to meet the new 10µg/l standard. Where it can be established that optimised treatment cannot achieve compliance with the final standard of 10 µg/l, there will be a need to continue with further programmes of work for strategic lead pipe replacement so that compliance can be achieved by December 2013. These programmes of work provide for the replacement of the water company's length of service pipe.
The installation and commissioning of new plumbosolvency treatment has been substantially completed for most companies and initial work on the optimisation of the treatment has demonstrated that it can be very effective in reducing lead concentrations in drinking water. However, for some, and possibly many, water companies, the programmes of strategic replacement of water companies' lead pipe will be required. Where water companies are planning strategic replacement of lead pipes, they will be required to give priority to areas where lead concentrations are highest, or where such measures would have a considerable impact on reducing exposure to groups potentially most affected by elevated concentrations of lead in the drinking water.
Under the 2000/2001 Regulations, water companies are required to replace their part of a lead service pipe if a consumer replaces his lead pipe. Additionally, water companies are required to replace their part of a lead service pipe if the standard of 25µg/l standard is contravened or if the water company has reason to believe that the 10 µg/l standard is likely to be contravened.
Further guidance on lead pipe replacement is currently being prepared as part of the Principal Ministerial Guidance for the 2004 Periodic Review of Prices for the years 2005 - 2010 (AMP4). This will be published shortly.
