More than 8000 motorists were breath tested by police who shut down key intersections into Hamilton city in a targeted operation at the weekend.

About 25 staff were involved in 'Operation Stocktake' which set-up checkpoints breathtesting motorists on Friday and Saturday night.

As a result, 3775 compulsory breath tests were conducted on Friday night and 5015 on Saturday.

District road policing manager, Inspector Freda Grace, said police ran the operation after a successful pilot last year.

"Instead of relying on a couple of booze buses at fixed points we identified key intersections that would mean if you came into town between 10pm and 4am you would have to go through us.

"Unfortunately it showed a lot of drivers are continuing to drive after they had been drinking."

A total of 123 people failed breath screening tests on Friday and another 196 failed on Saturday.

Grace said of those 319 drivers, 41 now faced excess breath alcohol enforcement action.

"In addition to those drivers, another two were suspended from driving on Friday and seven on Saturday.

"Six cars were impounded during the operation while eight people were arrested and 108 infringement notices were issued over the two nights for a variety of offences."

"In addition to the Road Policing related matters we had some really good feedback from our section staff walking the beat in the CBD on what are usually our two busiest nights.

"There were very few alcohol related incidents outside the bars, alcohol related infringements in town were virtually non-existent and overall arrest numbers were right down."