At least two of Manitoba's police forces want to use a new roadside test to check for drugs — but they don't know when they'll have it, or how they will pay for it.

Police services in Rivers and Morden have confirmed they will use the Drager DrugTest 5000.

Until they receive it, they will forge ahead with officers who are trained to detect drug impairment by observation, as will police forces that are wary of the device.

Recreational cannabis will be legalized in Canada on Oct. 17.

"We're as ready as everybody else is," said Bob Futrell, chief of the police service in the town of Rivers, about 220 kilometres west of Winnipeg.

He said his detachment isn't worried about having the only federally approved saliva screening equipment in time for legalization.

"Once we get that [device], obviously, we'll be more prepared, but some things do take a while."

Devices not purchased

The province said Thursday it hasn't bought any of the devices. A spokesperson said the Manitoba government is still waiting to see a funding agreement from its federal counterparts.

"In the meantime, we are working with police agencies to determine their needs, in an effort to help streamline the process once these issues have been addressed," the province's statement said.

The province did not respond to the CBC's question on how many Drager devices it wants.

Ottawa has earmarked $161 million over five years to cover police training and drug-testing equipment.

Morden Police Service Chief Brad Neduzak says he's ordered one of the devices for use in his southern Manitoba city, despite criticism the tool is unreliable in cold weather.

The manufacturer says the Drager test works best at temperatures between 4 C and 40 C.

"We are a little bit concerned about them, but at the same time, we have alcohol-screening devices as well that are sensitive to the climate," he said, explaining the device will be kept in heated environments to avert the issue.

A study published in the Journal of Analytical Toxicology also raised concerns about a number of false positive and false negative results, based on the device's screenings in Norway.

The Drager DrugTest 5000 works best at temperatures between 4 C and 40 C, the manufacturer says. (Drager)

Neduzak described the instrument as another tool police can use.

He's relying on promised federal funding to cover at least part of the cost, but he has not received confirmation. The device is valued around $5,000.

Police in Winnipeg, Winkler and Altona are still evaluating whether they want the devices, they told CBC News.

The RCMP did not answer a question about whether Mounties in the province will use the Drager device, but the force previously wrote in a statement it will have a "strategic, limited rollout" nationwide, in collaboration with provincial and municipal partners.

Drager not the be-all, end-all

The Drager tests for THC, the main psychoactive agent in cannabis, but does not provide the evidence necessary for a conviction. A further screening, such as a blood test, would be required.

Without a pot-screening device like the Drager, police forces will depend on standardized field sobriety tests and drug recognition experts.

People suspected of drug impairment will go through a series of sobriety tests.

If they fail the initial observation from a trained officer, a drug recognition expert will be called in. The accused will likely be taken to a hospital to obtain a blood sample, said police chiefs CBC News spoke to.

The Morden Police Service is among the most prepared forces. Among its 12 constables and two sergeants, 70 per cent of them have taken field sobriety training. They also have a trained drug recognition expert in-house.

"I like to think we're a little ahead of the game," Neduzak said.

So far, Altona and Winkler do not employ a drug expert. They plan to enlist the member in Morden on the handful of occurrences, annually, when drug impairment is suspected.

In Rivers, Futrell said one of his four full-time members can administer field sobriety tests.

Unknowns abound

Altona police Chief Perry Batchelor hasn't ruled out a roadside drug detection tool, but he wants to know about government funding first.

He said a standardized field test is not enough.

"I think it's a piece, but I think the instrumentation is important because an instrument will be calibrated, it will be tested, it will be approved and it kind of takes out that human factor," he said.

No matter how ready his force will be for legalization, Batchelor will continue to treat impaired driving as a danger to public safety.

"We've charged people with impaired driving, impaired by drugs or alcohol, for many, many years, so it's still based on an officer's observations and whether you have grounds to arrest."