§ 6. Sir John Biggs-DavisonTo ask the Secretary of State for Transport what measurements have been taken to assess the overall noise rise (L10 and L90) that has occurred on the M25; when and where they were taken; and what further measurements are proposed in the vicinity of the Theydon Garnon interchange.
§ Mr. Peter BottomleyNoise levels near the M25 were calculated by the prediction method set out in the Department of the Environment's publication, "Calculation of Road Traffic Noise". Additional noise surveys were carried out in 1985 on the A10-M11 section, in my hon. Friend's constituency, and in 1986 on the Wisley to Reigate section. No further measurements are planned at the M11-M25 Theydon Garnon interchange.
§ Sir John Biggs-DavisonHave not the predicted noise levels been exceeded, to the distress of my constituents? May fresh consideration be given in the Department to an acoustic barrier, a noise resistant road surface and the planting of more trees?
§ Mr. BottomleyI should like to continue to consider some of those matters, but I do not think that the expensive work can be agreed to. Perhaps I can write to my hon. Friend.
§ Mr. McCrindleTo endorse the point made by my hon. Friend the Member for Epping Forest (Sir J. Biggs-Davison), will my hon. Friend the Minister pay particular attention to the noise emitting from motorway surfaces? I do not know whether that is peculiar to this stretch of motorway, but there is no doubt that that seems to contribute, perhaps disappropriately, to the trouble suffered by his constituents and mine.
§ Mr. BottomleyI understand these genuine anxieties. I am advised that any given level of skid resistance, which is important on motorways — concrete and bitumen surfaces have the same noise characteristics — is undergoing further research.