She said it was important to highlight the hazards of consuming cannabis before driving - and the "exacerbation of those hazards" when alcohol is also consumed.
"I repeat my encouragement to the driving public to follow the cannabis and alcohol awareness and driving safety advice … and abstain from driving while under the influence of drugs and or alcohol," she said.
Her plea comes just two months after another Coroner warned of the dangers of driving while impaired by drugs.
Coroner David Robinson said he had reviewed nine separate motor vehicle fatality cases and found cannabis was implicated in six of those.
"If that sample is truly representative of the proportion of fatal driving cases where cannabis is implicated, the picture painted must be of real concern," he said.
Wallace, from Seddon, lived at the Awatere Motor Camp and was working at Medway at the time of his death.
The day of the crash he started work at 7am and was dropped off at home by a colleague at lunchtime.
In the afternoon he went to a pub in Renwick and while he was seen drinking beer he did not appear to be intoxicated.
Coroner Borrowdale said Wallace had a "documented history" of alcohol and cannabis use and convictions relating to both.
He also had 20 speeding infringements to his name - eight of which were in the three years leading up to his death.
His most recent drink driving conviction was in 2019.
Coroner Borrowdale revealed that in text messages sent shortly before he died, Wallace "expressed unwillingness to drive while under the influence of alcohol".
The night before he died a friend had invited him out but he declined.
"I best stay at home as I think I have had a few already and don't want to risk getting pulled over, so maybe another time," he replied.
"I'll save myself for tomorrow in Renwick."
Coroner Borrowdale said it was now impossible to know why Wallace declined to drive that night but got behind the wheel 24 hours later after drinking,
When he died his blood alcohol level was 186 micrograms per 100ml of blood.
The legal limit for an adult driver is 50 micrograms.
"Additionally, the presence of cannabis was confirmed in Mr Wallace's blood," the Coroner said.
"(The pathologist) noted the combined use of cannabis and alcohol tends to accentuate the effects of alcohol.
"Debris resulting from the collision was spread across a wide area, including a large number of beer bottles both full and empty and a quantity of cannabis leaf."
Wallace's cause of death was a serious open head injury that would have killed him instantly.
Police established he was driving 113km/h when he crashed - 13km over the posted speed limit.
They said evidence from the scene suggested "Wallace "intended to maintain a high speed" through the bend in the road where he crashed.
He approached the bend from the left of his lane, suggesting "bad steering by an inattentive or incapacitated driver".
He lost control and then attempted "a series of over-corrective steering manoeuvres to correct his initial misjudgment".
No vehicle or road faults were identified by police in their scene examination.
"Mr Wallace's decision to approach the curve ... And his inability to regain control of the vehicle were likely to have been influenced by his alcohol consumption along with the use of cannabis," police stated in their crash report.
"The dangers of driving after using cannabis are due to taking longer to respond to events, reduced ability to think clearly, and reduced ability to pay attention.
"The effects of cannabis may include distorted perception, difficulty in thinking, problem solving and loss of co-ordination."
Finally, police stated that had Wallace been wearing a seatbelt, his injuries would have been less severe.
"And may have been survivable," they said.
Coroner Borrowdale concluded the same.
"I find that the collision that claimed Mr Wallace's life arose through this combination of circumstances - each one of them avoidable," she said.
She made no formal recommendations but did urge drivers to avoid getting behind the wheel after drinking and or using drugs.
