The drinking water standard for lead reduces from 25 μg/l to 10 μg/l in December 2013 and companies will face some difficult decisions. Phosphate dosing allows the majority of supplies to meet the new standard but this adds to the long-term cost of supplying water and increases the phosphate load on wastewater treatment. The recently completed collaborative Portfolio project CP428, examined potential solutions for neutralising the impact of lead pipes, including their removal and the possibility of internal.
Since the project finished, some lining systems have now also achieved DWI Regulation 31 and WRAS approval. These offer the potential for trenchless technologies to coat the inside of the pipe, in-situ, using epoxy and polyurethane resins. The alternative is to remove the pipe and the CP428 project identified a cost-effect system that has been used in continental Europe for some years.
If pipes are not removed, an issue concerning DWI is the impact of network activity on transient lead concentrations at the tap, such as installing domestic meters. WRc has recently been commissioned to provide some answers. The objective of the research is to quantify the impact of the installation of a water meter (or a similar fitting) on the lead concentration in drinking water where properties are supplied through lead pipes. Trials are being carried out at WRc’s research facilities in Swindon using a purpose-built rig. This will be supported by sampling at selected consumers’ premises before and after the installation of such devices.
For further information contact Ian Walker on 01793 865155 or firstname.lastname@example.org