A3 Guildford A3 Capacity Improvements

The model was built to test on-line capacity improvement options for the A3 through the Guildford area. The model included around 128 zones covering the urban area of Guildford and the surrounding hinterland. The model comprised approximately 2600 nodes and 5600 links. Around 35 signalised junctions were modelled which included bus priority lanes and signal stages. Following calibration and validation (which comfortably exceeded WebTag criteria) the model was used to test four A3 improvement schemes - each one comprising a different package of measures that included widening and/or junction improvements. The impact of each package of measures on elements such as journey times and traffic flow was recorded on both the strategic and local road networks. A comparative assessment of the overall performance of each package was then possible. Following a positive review of the option testing results by Highways England the model was then used to carry out further tests on two A3 tunnel options.