Since the launch of the campaign, which started early this year to coincide with the World Cup, 3,518 vehicles have been stopped, and 2,878 breath tests carried out.
A third of all drug swipes were positive, with 63 people returning a positive test for drugs of 182 swipes carried out.
Superintendent Marc Lamerton said: “We launched our operation just over a month ago and to see figures this high is very concerning.
“Driving under the influence of alcohol and drugs is unacceptable, it can create a false confidence which can lead to an increase in risk-taking behaviour. We are committed to catching motorists who decide to get behind the wheel after consuming drugs or alcohol and put lives at risk.
“Over the last month we have seen drivers fined up to £415 and disqualified from driving for 46 months. The consequences of driving under the influence of alcohol and drugs are severe, and the minimum you will receive is a 12-month driving ban, a criminal record, and an unlimited fine or up to six months in prison.
“As we move nearer to the new year, we are urging those celebrating to do so sensibly, to plan their journeys home ahead of time and look out for their loved ones to ensure everyone gets home safely.”
South Wales Police and Crime Commissioner Alun Michael, said:
“These figures are a cause for concern - every single person who gets behind the wheel under influence of alcohol or drugs is putting innocent road users at serious risk, as well as themselves and their passengers.
“The figures also show that our roads policing officers are committed and out in force across South Wales trying to keeping our roads safe.
“Anybody caught drink driving will be arrested, charged and put before the courts within seven days where they face being fined, banned from driving and even jailed.
“Many people have already made the mistake – what they now face amounts to a devastating start to their New Year.
“My message to everyone is don’t let yourself be next. Always put safety, common sense, and the law first.”
Always check with your doctor or pharmacist if you are unsure about whether your prescription or over-the-counter medication will affect your ability to drive.
Anybody who has concerns about anybody they believe to be driving under the influence are asked to contact police on 101 (or 999 if they are posing an imminent danger) or alternatively, contact Crimestoppers anonymously on 0800 555 111.