I have received a response from the Chief Executive of the Highways Agency about the M4 improvements and motorway noise:
“Thank you for your letter about the proposed M4 Junctions 3 to 12 Smart Motorway scheme and the possible increase in noise levels for local residents.
We are currently undertaking an environmental assessment to determine the impact the scheme may have on the environment. The assessment considers air quality, landscape and nature conservation as well as noise and vibration and will identify any mitigation measures required. These may include the use of noise barriers made of materials which absorb noise, like those close to Junction 10, and low noise road surfacing.
The results of the environmental assessment will be available at exhibitions planned for the autumn. We will notify you of the dates and locations of the exhibitions nearer the time.”