Official critique of Transport Assessment published
Powys CC and WAG asked Halcrow Group to audit the Transport Assessment written by Colin Buchanan, that was submitted with the planning application for a Tesco store in Machynlleth. Here are some of the findings:
“Significant concern” about the proposed site access
The proposal is to control this by 3 way traffic lights, with the south side primary signal head mounted on a mast arm over the carriageway.
Halcrow says this would “impact adversely on adjacent properties” and that “the carriageway visibility of the signal head will be sub-standard”.
Other concerns near the site
Traffic queuing from the Town Clock direction to these traffic lights would “cause particular difficulty for residents of Tanrallt Street”.
Heol y Doll footways “have significant lengths close to 1m in width, which will be a considerable impediment to choosing to access the store by foot.” “It will be necessary for pedestrians to step in to the carriageway if required to pass others.” “It is likely that transporting several shopping bags will be at best awkward and in some places unsafe.”
Traffic data should be re-calculated
Halcrow rejects Buchanan’s argument that holiday traffic is only of significance on four days a year (August market days). “To account for holiday traffic, 17% of the base traffic should be added to the predicted 2010 and 2025 flows.”
“Trip patterns must be re-examined” as well, due to errors and poor assumptions about where shoppers would travel from. Buchanan worked on the assumption that many people currently travel north from Machynlleth to shop and that traffic over the Dyfi Bridge would be reduced if they shopped at Tesco instead. “This is at odds with the Household Survey”. It is likely that there would be more traffic over the bridge, not less; mainly because Tesco will draw people from Meirionnydd who currently shop at Tywyn and Dolgellau, but also because “some visitors [from the east] will use the B4404 [through Llanwrin] to access the store”, to avoid the congested Town Clock junction. “This may give rise to further concerns both in respect of the A487/A493 junction and the integrity of the adjacent Dyfi Bridge.”
Mini roundabout unacceptable
Buchanan proposed a mini roundabout at the Town Clock junction because it “will be significantly over capacity with the development”. Halcrow says the design “operates less efficiently than claimed”. “There are visibility and geometric concerns” and the proposal “is unacceptable”.
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