Ontario’s new zero blood-alcohol level policy for young drivers takes effect at midnight Saturday.

Starting Aug. 1, novice drivers aged 21 and under will be subject to strict penalties if found with any alcohol in their systems, including an immediate 24-hour suspension of their licence, an extended 30-day suspension and up to $500 in fines.

The province announced the change this month in a bid to curb alcohol-related incidents.

"Young drivers between the ages of 19 and 21 are most at risk," Transportation Minister Kathleen Wynne said in a statement. "We are doing what we can to keep them safe."

'There’s been too much bloodshed, too many injuries, too much death.'—Sgt. Tim Burrows, Toronto police

Drivers holding G1 and G2 permits in the graduated licensing system are already subject to a zero-alcohol restriction, but the introduction of a new class of novice driver is a change.

Police are advising young drivers to plan ahead if they plan to go out this long weekend.

"If they leave home tonight to go to a bar, they're perfectly legal," Sgt. Tim Burrows of Toronto police told CBC News. "But if they drink while they're at that bar, and at 12:01 [a.m.] they have any alcohol in their system, they'll be breaking the law."

The Ontario Ministry of Transportation says drivers between 19 and 21 are nearly 1½ times more likely to be involved in fatal drinking-and-driving accidents as any other age group. In the last decade, 235 drivers under 21 have been killed in alcohol-related collisions in the province.

"There’s been too much bloodshed, too many injuries, too much death," Burrows said. "Any amount of alcohol is too much when you’re driving a car."