The exclusion zone centred around the Rena wreck at Astrolabe Reef is set to be reduced to two nautical miles this week.

Bay of Plenty Regional Council water group manager Eddie Grogan says the three nautical mile or 5.5km exclusion zone is changing.

The exclusion zone of three nautical miles around Rena at Astrolabe Reef.

The current exclusion zone was set late last year after the larger exclusion zone declared following the loss of containers off Rena in an October storm, was reduced.

The size of the zone is a result of requirements of the salvage company Svitzer, cargo clean-up company Braemar Howells, harbourmaster and the council.

'We are in the process at the moment of designing the notices and signs and everything,” says Eddie.

The exclusion zones are being policed through the harbourmaster and by contractors.

Eddie says he's unaware of people voicing hostility towards the council and frustration at the manner in which the exclusion zone is being policed.

People who are unhappy at the way they are being treated by the contractors are asked to contact the harbourmaster.