Four people were arrested on the Saturday of Schoolies Festival in Victor Harbor, but police say it was an overall successful celebration.
Three out of four arrests made on day two of the festival were for drug-related offences.
Among them was an 18-year-old Henley Beach man, whose car was searched after a report of it being "suspicious", according to the festival police commander Superintendent Mark Fairney.
Patrols found the car on Bay Road just before 6.30pm and upon seeing empty plastic bags in the car, they enlisted the help of drug detection dog Taco.
A small amount of cannabis, 34 ecstasy pills and a set of scales were found in the car, and as a result the man was charged with drug trafficking, and was bailed to face Victor Harbor Magistrates Court in January.
A second arrest occurred when an 18-year-old Wayville man was found with 13 capsules, believed to be MDMA, and he was charged with trafficking a controlled drug.
He will also face Victor Harbor Magistrates Court in January.
Supt Fairney said police had been proactive in policing caravan parks when it came to locating sources of illicit drugs.
"There had been reports of people mixing illicit drugs with alcohol then presenting (to paramedics)," he said.
"All of our reports and arrests have been due to proactive policing."
A non-school leaver from Goolwa was reported for carrying a folding knife in his backpack while riding a bike without a helmet.
There were 38 expiations handed out, which included 32 for breaking dry zone rules.
"Given the sheer number of Schoolies in Victor Harbor, I'm not alarmed by that number," Supt Fairney said.
He said there was an increase in presentations to first aid, but compared to Friday night, where most of those presentations were drug-related, Saturday night's were primarily due to alcohol-related issues.
"It's really pleasing that there's been no incidents inside Schoolies Festival, people are generally having a good time," he said.
Supt Fairney said driver testing stations would be set up on routes out of Victor Harbor on Monday and reminded school leavers that illicit drugs can remain in their systems for 24 hours.
"If they plan to be driving home, they should be thinking about that now and this evening," he said.
For the first time since Encounter Youth took over operation of the festival 21 years ago, the state's premier came to check out the festival site on Saturday.
Encounter Youth chief executive Nigel Knowles said premier Steven Marshal spent over an hour with Green Team members and going through the whole operation.
"He was very impressed and very please to see the operation," he said.
Mr Knowles said 5000 school leavers enjoyed the 80s costume theme on Saturday night and looked forward to seeing them spend one more night celebrating on Sunday night.
"We remind young people that you may be a little tired after two nights, so take care of yourself and your mates," he said.