The new roundabout at Middle Renwick Rd and Boyce St in Blenheim is sporting a new-look "wavy" design.
Marlborough Roads manager Frank Porter said the intersection had been "technically challenging to design".
The roundabout was designed to provide "adequate drainage", he said.
"We also have to ensure there is sufficient slope at the roundabout so that water drains easily off the road surface.
"As well as getting the slopes correct for drainage, the surfaces have to enable smooth turning manoeuvres and it is a complex matter to achieve the correct design."
When completed, surface levels would align with existing kerbing, channelling and the rest of the road surfaces leading up to this intersection, Porter said.
"Drivers will be able to smoothly enter and exit from the roundabout."
Currently the roads leading up to the intersection were different heights - there is a 330-millimetre difference between the highest and lowest points.Once work was complete, the difference would be "almost indiscernible", he said.
Porter said work was going really well and the contractor was "on or even slightly ahead of our programme".
The new roundabout at the intersection of Murphys, Battys and Middle Renwick roads was also on track; a temporary roundabout would be operating by the end of the week, Porter said.
- The Marlborough Express
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