South Australia will bring wastewater drug testing to country areas under a strategy to tackle tobacco, alcohol and illegal drugs.

The State Government's five-year strategy aims to reduce the number of South Australians who drink at "risky levels" by 30 per cent by 2020 and includes $1.3 million over four years to increase the availability of drug and alcohol clinicians to respond to referrals from the Department of Child Protection.

Substance Abuse Minister Leesa Vlahos said previous strategies had coincided with a drop in tobacco use.

She described the strategy's aims as "ambitious" but necessary.

Ms Vlahos said while the strategy aimed to address methamphetamine use, alcohol remained the most commonly consumed and misused drug.

"In fact 2.1 per cent of the total deaths in Australia are associated with drinking at risky levels," she said.

She said regular wastewater treatment testing showed "we are making inroads in tobacco, alcohol and drug misuse in our state".

The testing, which involves scientists analysing sewage from treatment plants, will be expanded to country areas.

Emergency Services Minister Peter Malinauskas said there was a strong relationship between family violence and alcohol and other drug misuse.

He also said in 2015 22.4 per cent of drivers or riders killed on the road and almost 15 per cent of those seriously injured had blood alcohol concentrations above the legal limit.