Police arrested 666 impaired drivers across Hampshire and the Thames Valley in December as part of their drink-drive campaign, Operation Holly.
Officers arrested 391 people for drink and drug driving offences in the Thames Valley region, and 275 were arrested in Hampshire.
Compared to last year’s campaign, the average number of drink drive arrests has fallen by 5%, while the figure for drug drivers has increased on average by 28%.
Road Safety Sergeant Rob Heard, from the Roads Policing Unit for Hampshire Constabulary and Thames Valley Police said:
“This year we have been very intelligence-led and worked closely with our partners from other organisations to help remind people of the dangers and consequences of impaired driving.
“We’ve seen a small drop in the number arrested for drink driving, which is good however there continues to be a steady rise in the number caught for drug driving over the last few years.
“We need to consider that the increase in drug driver arrests is not necessarily because we have more drug drivers on the road but that officers can conduct road side drug testing, using drug analysers to test for a level of certain illegal drugs in a person’s saliva, which wasn’t available pre-2015.
"The difference being that there only needs to be a trace of one of the eight illegal drugs and no proof of impairment is required for a conviction.
“Different drugs will vary in the time they take to process through your system, some can still be measurable and at an illegal limit to drive some days after use depending on amount and frequency of use."
Over 4,200 breath tests were carried out during the Operation Holly period by roads policing officers with 155 blowing over the drink drive limit.
Over half of the 284 drivers tested for drugs had a positive result for drugs; 150 people who had a drug wipe test had a trace of drugs in their system.
A further 26 were arrested for failing a Field Impairment Test (FIT).
The worst offending drink driving age group were 35-49 years and the highest number of drug drivers were aged 17-24.
Road Safety Sergeant Rob Heard added:
“Our message is simple – don’t mix drink or drugs with driving, they may stay longer in your system than you think – It’s not worth the risk.
"Such behaviour on our roads has far-reaching effects not just for the impaired driver, but for any innocent road users affected by their destructive decisions.
"It is disappointing that some people still take that risk.
"Too many people continue to be complacent about the realities of road deaths and serious injuries.
"That’s why we want everyone to be clear about their responsibilities, and have respect for each other on the road.”
If you know someone who drinks or takes drugs and drives you are advised to call police on 101 or, if it’s an emergency, dial 999.
If you don’t want to speak to police or give your name, call Crimestoppers anonymously on 0800 555 111.