A well-used roundabout is set to shut overnight for more than two weeks. The A20 Coldharbour Roundabout in Maidstone will be closed as part of a £5m project. It is now three months into the A20 improvement scheme, which is set to be completed by mid-December. The project will see the junction enlarged from two lanes to three around the roundabout, with additional lanes provided on the approaches. Kent County Council (KCC) says it will help reduce congestion in the area and boost air quality. So far, contractors Breheny has been working on digging out the foundations for a new footpath and verg…