§ Mr. Michael Robertsasked the Secretary of State for Wales what study has been made of the pollution effects of motorway traffic on water supplies; and what consideration has been given in this regard to Llanishen reservoir and other storage and water pumping stations in the vicinity of the proposed line of the M4.
§ Mr. Peter ThomasThe Warren Spring Laboratory has carried out research into lead concentrations from motorway traffic and will undertake more general studies over the next five years to measure carbon monoxide, hydrocarbons, lead and particulate matter in relation to traffic density and weather conditions at five roadside sites, including one in Cardiff. In addition all interested authorities in Wales have recently been advised of the appropriate steps to be taken in the event of inland oil spills as they affect water supplies. The Llanishen reservoir is to be phased out from public water supply use before work on the M4 extension is due to be completed.