The Blossom Festival on September 26-28 and the Merino Shears event the following week would both have bans.
The ban covers a wider area than previous years and is now extended to the Teviot Valley, following a Central Otago District Council decision in December.
Alcohol could still be consumed on licensed premises and private property. The ban applies only to public land.
"We’re asking people to familiarise themselves with the areas covered, so everyone can enjoy the festivities and stay safe," a police spokesperson said.
The extension to the ban covered from Alexandra to Raes Junction, including 2km either side of State Highway8.
In the report presented to the meeting Sergeant Adam Elder said there was a "contingent of vehicle enthusiasts" who would meet at Raes Junction and travel to the Blossom Festival.
All were usually drinking alcohol and causing disorder in the towns they stopped in, he said.
"There would be significant benefit to extending the liquor ban through the Teviot Valley including Millers Flat, Ettrick and Roxburgh for future Blossom Festivals."
Sgt Elder also requested the Alexandra liquor ban be extended to include the Merino Shears, due to previous incidents in the carpark of the Stadium Tavern.
At the meeting Central Otago Mayor Tamah Alley said the carpark was council property which meant ratepayers were responsible for paying to remove rubbish and glass left behind.
