Acting Senior Sergeant Graeme Evans said police set up a checkpoint in Wharf St on Thursday night.
During the two-hour stint, 403 vehicles were stopped.
Sixteen drivers tested positive for alcohol and were required to undergo breath screening tests.
Only one of the 16 was over the legal limit and was charged with driving with excess breath alcohol.
Despite the low number, Snr Sgt Evans said a good result would have been if no-one was over the limit.
"It could have been better," he said.
"It could have been no-one which is what we’d prefer."
It meant there was still one person within the group who did not get the message not to drink and drive.
One person was also required to undergo an impairment test.
Snr Sgt Evans said the person had not been charged but once results of blood tests were received a decision would be made on what the charges will be.
The person’s alleged impairment was "not related to alcohol".
Snr Sgt Evans said it appeared people were surprised to run into the checkpoint.
People could expect the amount of checkpoints and the "booze bus" out targeting drink drivers to increase as the summer continued.
Snr St Evans said if people knew they would be drinking then they should not be driving.
