Crown witness Adrian Barclay, a club committee member and junior surf co-ordinator, said Dunnett had taken up a coaching role at Ocean Beach 2010.
He said the police officer ran the surf squads "really well" and was a "valuable contributor" to the club.
During cross examination, Dunnett's lawyer, Jonathan Krebs, asked Mr Barclay about the "social elements" of the club.
"I would say it is one of the more social clubs in the Hawkes Bay Area," said Mr Barclay.
He said since the alleged incidents occurred, a more "stringent" alcohol policy had been implemented to prevent underage drinking.
Crown prosecutor Gavin Thornton said Dunnett had asked a complainant if "she was going to tell anyone".
Following a separate incident Mr Thornton said Dunnett told two girls he was a police officer, they were drunk and "no one would believe them".
He said in total there were five different "events or episodes".
Dunnett is still employed with police but is currently suspended on full pay.
The trial, before Judge Les Atkins QC, continues this afternoon.