By RNZ

Police say they have been catching "unfortunate" numbers of drink-drivers in blitzes around the country.

Last weekend in Hamilton, 71 people were over the limit, out of about 10,300 tested - one in every 145 drivers tested.

And one man was caught drunk driving twice in one night.

In two weekends in the Bay of Plenty last month, 180 people were caught driving while impaired. On the first weekend, officers found one in every 83 vehicles stopped was driven by a drunk driver, and the next weekend, the drivers of one in 75 vehicles stopped were over the limit.

In Northland, police said they are prosecuting about 30 drink-drivers each week.

"Many of these are from remote rural communities, and are travelling long distances on open roads with 100km/h speed limits," the statement said.

"That means that smallest of mistakes made by an impaired driver can have devastating results."

In Auckland, 2921 drivers were breath tested in May, and 102 were processed for drunk driving.

In Canterbury, 8003 tests were carried out in May, and 48 people tested over the limit.

Police said Wellington had comparatively fewer drivers nabbed over the limit: of about 4600 people tested in two weeks in May, 22 were caught with excess blood-alcohol.

National Road Policing Centre director Superintendent Stephen Greally said officers at the checkpoints also talked to drivers who had been drinking, but who tested under the legal limit.

"In an ideal world we would catch no one driving with alcohol or drugs in their system. Impaired drivers are more likely to cause crashes. That's just a fact.

"Our advice is always the same; if you're drinking, don't drive. Organise a way to get home before you go out drinking."

Greally said checkpoints would be set up to monitor traffic throughout the country this long weekend.