GRIDLOCK could cost York more than £80 million a year by 2031 if building thousands of homes is not matched by sweeping transport improvements, experts have warned.

The cost to the city will soar over the next 18 years and motorists have been told they must cut their car use, to prevent York’s roads coming to a standstill.

An assessment of the city’s congestion has revealed only expensive major schemes – such as dualling the Outer Ring Road’s busiest sections – will cater for the impact of the new developments proposed under City of York Council’s draft Local Plan.

Otherwise, drivers using main roads into and out of York are likely to see a 30 per cent increase in journey times, adding nine minutes to a half-hour journey.

The transport report forming part of the Local Plan said that without huge transport upgrades, delays could nearly treble and congestion costs would rise from £31 million to £83 million. It said improvements the council is confident can happen during the plan’s lifespan will not be enough on their own.

The gridlock bill was calculated by multiplying a generalised congestion-cost figure by the total hours motorists are delayed on York’s roads. This is currently 2,242 hours annually, but could reach 6,042 hours by 2031.

The report said £90 million of schemes envisaged by 2030 included the James Street link road’s final phase, outer ring road junction improvements, a Haxby rail station and a new Clifton Moor Park&Ride site. However, it said: “Large sections of the outer ring road are approaching or exceeding capacity, even with roundabout improvements.

“This appears to show the infrastructure improvements in the reference case alone are insufficient to cater for the additional demand on the network arising from future growth.”

It said queues on major roads could mean residents being “forced on to less suitable routes”, although flexible working, more public transport use, traffic management and changes in travel attitudes could help.

Coun Dave Merrett, cabinet member for transport, planning and sustainability, said: “Congestion has been increasing in York for years, and this is only set to get worse unless we take action. 

“We have been taking steps to get funding in place to upgrade the outer ring road, expand Park&Ride further, create a bus/rail interchange, improve bus priority measures and services to make them more attractive and increase cycling and walking. We will also look to new developments to contribute towards additional measures on top of this.

“But, ultimately, only by changing the way we travel will we be able to prevent congestion becoming a much more serious problem for the city.”

Coun Joe Watt, Local Plan spokesman for the Conservatives, said his party had lobbied for the Outer Ring Road to be dualled since 2007 “in the face of criticism from Labour that it is unsustainable”. He said the authority’s housebuilding targets were “cloud cuckoo land” without major roads investment.

Labour’s Local Plan includes 22,000 new homes by 2030.