An independent report by Cardno, a professional infrastructure and environmental services company, shows that a bypass
to the east of Blenheim would not alleviate traffic congestion along State Highway 1/Grove Road. The report was
commissioned by Marlborough District Council and will be presented to the Assets and Services Committee this Thursday.
Councillor Francis Maher, Regional Transport Committee Chair, says the report shows that the volume of traffic
travelling through Blenheim using State Highway 1 from the Wairau River to Riverlands without stopping is less than
1,000 vehicles a day, while traffic volumes circulating in Central Blenheim are 24,500 vehicles a day.
“The through traffic equates to just 8% of overall traffic flows.”
“The number of vehicles travelling through Blenheim from Koromiko to Smith’s Overbridge at Redwood Pass is only 285 on
an average week day, or 4.6% of the overall total.”
“It’s clear that the volume of vehicles passing through Blenheim is a very small proportion of the traffic. Building a
bypass would therefore not reduce traffic congestion because most of our traffic is local trips.”
“We recognise there is traffic congestion at peak times on Grove Road and I’m pleased to see the report suggests a
number of short term improvements to some intersections that would help,” he said.
The data was collected in October 2019, well before the COVID-19 pandemic. A review of turning counts at the three
roundabouts on SH1 (Nelson Street, Alfred Street, Redwood Street) shows a higher proportion of right turning movements
than at typical intersections. There is a high level of traffic demand between Nelson Street and Sinclair Street in the
north, and Redwood Street and Main Street in the south.
The Regional Transport Committee recommended the report is forwarded to Waka Kotahi NZ Transport Agency to consider,
including the suggested improvements:
· Adding an extra northbound lane at the Alfred Street intersection
· Installing a roundabout at the Budge Street intersection
· Removing some short-term parking along Grove Road
· Reviewing the operation of the railway pedestrian crossing
· Reducing the length of the traffic island at the northern exit to the Redwood Street roundabout.
Councillors will hear a presentation by report author Laura Skilton at the Assets and Services Committee meeting this
Thursday. The full report is here