The Spit at Aramoana, Whareakeake (Murdering beach), Karitane and Papatowai in the Catlins are now protected as nationally significant surf breaks in the New Zealand Coastal Policy Statement.
The policy states that coastal activities must not adversely affect protected surf spots.
Conservation Minister Kate Wilkinson said the national policy statement, which replaced an earlier policy, gave councils clearer direction on protecting and managing New Zealand's coastal environment, including surf breaks, for the first time.
"The emphasis is on local councils to produce plans that more clearly identify where development will need to be constrained to protect special areas of the coast."
Ms Wilkinson said the policy's scope included the protection of outstanding natural features and landscapes, planning for subdivision development, protection of biodiversity and water quality, and management of coastal hazard risks.
South Coast Boardriders Association committee member Brett Hastie was pleased the surf spots would have increased protection.
The club made a submission on the policy, which was an exciting development as, for the first time, surf breaks had been afforded such protection, Mr Hastie said.
He believed the policy increased the hurdle for Port Otago's Project Next Generation, which proposes to widen and deepen the shipping channel to attract bigger ships.
The project is opposed by surfers because of a proposed 7.2 million cu m dumping of sand and silt about 6km off Taiaroa Head.
"Hopefully, [the coastal policy] means [Port Otago's proposal] won't go ahead," Mr Hastie said.
He did not accept Port Otago's reassurance the proposed dumping was too far out to sea to affect surfing.
Mr Hastie said the Spit was affected by Port Otago's normal dredging activities, and the massive dredging proposal would make things worse.
Veteran surfers insisted surfing at Aramoana had deteriorated in the past 30 years or so because of dredging dumps, he said.
Port Otago chief executive Geoff Plunket dismissed Mr Hastie's concerns as "rubbish", and drawing a "long bow".
The proposed mass dumping of sand and silt was too far out to sea to affect surfing, he said, and existing dredge dumps had helped, not hindered, surf quality at Aramoana.
Port Otago tried to please local surfers with the timing and location of dredge dumps.
Mr Plunket felt the relationship between the port and surfers had become "a wee bit unbalanced" with surfers not willing to compromise.
Mr Plunket did not expect the new coastal policy to affect the channel-deepening proposal.
A resource consent hearing is set down for March.
