The Marlborough District Council has welcomed an interim Environment Court decision controlling the speed of vessels operating in the Marlborough Sounds.

As part of the Council's management plan, operators of newly introduced vessels of over 500 tonnes need to obtain resource consent if they wish the vessels to exceed 15 knots.

Any ships exceeding that speed would be required to comply with a wash rule, limiting ship wake energy.

Ferry operators Toll and Strait Shipping opposed the plan.

At the Environment Court hearing earlier this year, the council argued that the wake from faster ferries was causing the banks on Tory Channel and Queen Charlotte Sound to erode.

Toll's counsel Stephen Kos told the court the council had not proved the banks were eroding "above the already erosional nature" of the Sounds.

Marlborough Mayor Alistair Sowman said the decision endorsing the plan was a win both for the council and for shipping operators.

"It is a win for the council and the people of Marlborough because it supports our desire to limit the wake effects of large vessels in order to protect the environment for future generations."

The court has ordered the council and shipping operators to work together to finalise an arrangement by July 17.

The council will then submit it to the court for a final decision after which it will go to the Minister of Conservation for approval.