B Double trucks would not be allowed to travel on a considerable number of Yorke Peninsula roads at night or during wet conditions, under a new roads strategy from the Yorke Peninsula Council.
The strategy has raised the ire of the South Australian Road Transport Association and Grain Producers SA, who say it would severely impact agricultural productivity, increase transport costs for primary producers and increase road safety risk.
Other proposals in the strategy include limiting speeds on roads with 'priority one' issues to 30 kilometres an hour, and changing speed limits on all HML permit approved networks to 50km/h.
Primary producers would also need to contribute an extra $600,000 for road repairs if the council's strategy is adopted.
The Heavy Vehicle Access Strategy was compiled with the view of managing the wear and tear on the region's road network which includes 3143 kilometres of unsealed roads.
A consultant determined 12.7 per cent of those unsealed roads were affected by P1 issues at 152 locations and 23.1pc were affected by P2 issues at 280 locations.
With inadequate funding to fix all issues, the Council believes managing the risk through heavy vehicle restrictions and an extra $600,000 a year contribution from farmers is the best approach.
Proposed restrictions on heavy vehicles on roads with P1 issues include "speed reductions to 30km/hr coupled with the use of amber rotating hazard beacons" and "no gazette or permit HV operation in wet conditions and no operation for the same outside of day light hours (between 5pm and 7am to cover winter)".
SARTA executive officer Steve Shearer said many transport operators in the region were unaware of the proposals until a recent article by the Yorke Peninsula Country Times.
"If the industry can't use B-Doubles, there will be 50pc more trucks on the road to get the job done, which would be utterly counter-productive," he said.
"It would increase road congestion, increase road safety risk, increase emissions and dramatically increase the cost of transport for primary producers, probably harming their capacity to compete in the market."
Mr Shearer said the mere suggestion of no night time travel was "absurd".
"It would dramatically increase the number of trucks on the road during the day, because the freight still has to be moved," he said.
"Suggesting 30km/hr speed limits shows a lack of appreciation of the fact that fuel is typically a third of a truck operator's cost structure and at 30km/hr the fuel consumption sky rockets, again hiking the transport costs for farmers."
If the strategy were to be adopted, Grain Producers SA chief executive officer Brad Perry fears harvest would be prematurely paused in areas where unsealed roads were the only option to get grain off-farm.
"Suggestions such as reducing speed limits, night curfews and restrictions in wet weather for heavy vehicles raise more questions than answers," he said.
"What constitutes daylight hours? How wet will be too wet for a heavy vehicle to operate? Who would police the new speed limits for heavy vehicles?"
Mr Perry said lack of road maintenance was the main cause of safety risks and deteriorating unsealed roads across the state and the issue needed immediate attention.
"The South Australian grain industry is a $4 billion sector, and the Yorke Peninsula plays a critical role in this," he said.
"We understand safety is paramount and that some of these unsealed roads are in very poor condition.
"It's important to understand how much grain is carted on these roads and if there are alternative options, what the cost will be for grain producers to go around these roads if restrictions are put in place."
The Yorke Peninsula Council has been contacted for comment.
