Another person has died on South Australia's roads, adding to the horror start to the year, while SA Police have new powers to take licences away from drivers detected using drugs.
SA Police say a 49-year-old Mount Gambier man died after his truck left the Riddoch Highway at Penola and crashed into a tree about 10pm on Friday.
The driver and sole occupant died at the scene in the state's south-east.
The Riddoch Highway remains closed between Robe Road and Mount Burr Road, with drivers diverted from the Penola highway bypass to the main street of the town.
The death brings the lives lost on the state's roads to 18 this year, compared with four at the same time last year.
On Saturday morning, a cyclist suffered life-threatening injuries after a collision with a BMW convertible on Norton Summit Road at Woodforde, in Adelaide's east.
Police said the 34-year-old male cyclist from Teringie was taken to hospital in a critical condition.
The car driver, a 20-year-old Kensington Gardens man, was charged with causing serious harm by dangerous driving and aggravated driving without due care.
Also overnight, a man was charged with drink-driving after crashing his car into a house in Adelaide's northern suburbs.
Police spotted the sedan speeding at Davoren Park at around midnight and tried to stop the vehicle, but it allegedly sped off on Whitington Road.
A short time later, they found the car crashed into a parked car and a house on Pix Road.
A 21-year-old was charged with drink-driving and other driving offences.
New drug-driving laws imminent
Separately, drivers caught with drugs in their system will have their drivers licences immediately stripped under new police powers.
The move takes effect on Monday, allowing police to immediately suspend a licence if a driver tests positive for cannabis, methamphetamine or MDMA.
Currently, an offending driver can retain his or her licence until it is suspended by a magistrate.
Assistant Police Commissioner Ian Parrott said it was a significant tightening of the law.
"We think this is a really important step in preventing those people who choose to use drugs and drive on our roads," he said.
"Twenty per cent of lives lost of the last five years have been as a result of people using drugs and driving."
More than 5,500 people were caught drug-driving in South Australia last year.
"There are really simple things that people can do to eliminate and mitigate against dying on our roads," Emergency Services Minister Joe Szakacs said.
"The fact that one in five people who have died on our roads in the last number of years had drugs in their system should be shocking."
It is not known if any of the crashes this year were because of drug drivers.
