§ Mr. David Howell
To ask the Secretary of State for Transport what studies his Department has made of the comparative costs of road resurfacing as between conventional asphalt surfaces and porous asphalt; what plans he has for a further use of porous asphalt in order to reduce road noise; and if he will make a statement.
§ Mr. Key
[holding answer 20 June 1994]: This question concerning road surfacings is an operational matter for the Highways Agency. I have asked the chief executive, Mr. Lawrie Haynes, to write to my right hon. Friend.
Letter from Lawrie Haynes to Mr. David Howell, dated 7 July 1994The Minister for Roads and Traffic, Mr. Robert Key, has asked me to write to you in response to your question relating to comparative cost of porous asphalt and its use.The Highways Agency monitors the cost of porous asphalt on contracts. These studies indicate that, for heavily trafficked trunk roads, the comparative cost of porous asphalt can be between 50 per cent. to 100 per cent. more expensive than conventional asphalt surfaces. This relates to the cost of the material itself. There are additional costs for increased road thickness to compensate for the lower strength of porous asphalt surfacing and for provision of appropriate drainage. While there are also indications that additional winter maintenance will be needed figures are not yet available for this.The criteria for using porous asphalt were presented by the Minister to the House in the adjournment debate on 15 May 1992 and permit use where conditions are suitable and it is cost effective. They are set down more fully in Press Notice No. 204 issued on the 28 July 1992 a copy of which I attach. Porous asphalt surfacing is being considered for use on schemes within the criteria laid down.