When I first met Kieran Collins in Vancouver three years ago, he had a $100-a-day street heroin habit that he fed any way he could.

"You're doing things that you don't really want to do — things that you weren't raised to do," said Collins, who was 36 at the time. "You know they are wrong, but you get accustomed to having to feed it."

He's still hooked, but a lot has changed.

Back then, Collins was haggard and desperate. He referred to his 20-year addiction to opioids as "a monster" as we sat in a park in Vancouver's Downtown Eastside, and he talked about what he thought would happen to him if things didn't change.

"I will be dead in not long," Collins said. "I have overdosed a couple of dozen times ... one of these times I won't come out of it.

"It's not the way I would like to go," he added. "Especially how that would make my family feel."

Fearing street drugs would one day kill him, Kieran Collins was desperate to get into a controversial program in 2016 at the Crosstown Clinic in Vancouver. It helps drug users manage their dependency on heroin by giving them controlled doses. 0:43

Since I spoke with Collins in 2016, the opioid crisis gripping Canada has killed more than 10,000 people.

In British Columbia alone there have been so many overdose deaths that average life expectancy is actually going down in the province.

Collins has managed to stay alive through this crisis. He credits a unique, controversial clinic's approach to dealing with people who use drugs.

WATCH: The National's story about Vancouver's free heroin clinic, in the coming days on CBC Television and streamed online

Free heroin

Twice a day, Collins visits the Crosstown Clinic in Vancouver's Downtown Eastside. A nurse hands him a syringe of prescription-grade heroin.

It's just enough of a dose so that he doesn't go into withdrawal.

"It's not like this makes the problem just go away," Collins says, but it allows him to function.

In total, 140 people are prescribed heroin at the clinic. For each of them, other treatments such as methadone haven't worked.

After they take their shots, clients of the Crosstown Clinic in Vancouver gather in the meeting room while the drugs take effect to make sure there are no complications. (Nick Purdon/CBC)

The idea behind the program, which is publicly funded by the province, is that if users like Collins have a clean supply of heroin, they won't take street drugs like fentanyl — which was responsible for about 87 per cent of illicit-drug overdose deaths in B.C. last year.

After his shot, Collins takes a seat in the waiting room with some of the other users. It's a precaution in case there are complications.

Another patient sitting nearby, 58-year-old Kevin McGarragan, says the program has saved his life.

"If I wasn't here I'd probably be in an urn or underground."

Kevin McGarragan says the Crosstown Clinic has saved his life by allowing him to avoid street drugs. (Nick Purdon/CBC)

Dr. Scott MacDonald, the lead physician at the clinic — the only one in the country that prescribes diacetylmorphine, the medical term for heroin — says the way to curb the crisis is to stop viewing opioid addiction as a criminal problem.

"This is a treatment for a chronic relapsing illness, just like diabetes and high blood pressure," he says.

"We need to get away from thinking this is a criminal problem — it is a medical problem and it is a chronic, manageable illness."

'A chance at being human again'

When Collins is cleared to leave the clinic, he thanks the staff and heads off to meet his father who works across the city in a design studio.

On the way I ask Collins how his life has changed since he began getting his heroin from the clinic.

At first he's a bit defensive.

"They're not medicating us to the point where we are like 'arghhhh,'" he says throwing his head back and rolling his eyes. "They just give us enough so that we are not a mess. So we can feel what it is to have a chance at being human again.

"Before, it felt like I was almost just existing," Collins explains. "But now, some days I wake up and it's like whoa, I am lucky to be alive."

Kieran Collins says low-dose injections at the clinic keep his addiction under control and allow him to live a more normal life. (NIck Purdon/CBC)

Collins stayed in touch with his father throughout his 20-year addiction — but only since he started on the program has he reconnected with the rest of his family.

"I'm an uncle now, my little sister has a kid," he says proudly. "I see him all the time."

Kieran's father, Wayne Collins, likes to joke that his hair is white from worrying about his son.

"I've nursed him through comas," he says. "I've nursed him through him having fallen out of a three-story window, wondering if he's going to come back to me."

Father and son hug for a moment before Wayne gives Kieran directions about the work he wants him to do cleaning up the studio. He says the biggest change in his son since starting on the heroin program is that now when Kieran says he'll do something, he follows through.

Kieren's father Wayne says his son has changed for the better since he started visiting the clinic for regular injections. (Nick Purdon/CBC)

When Kieran was feeding his habit on the street, he'd disappear for months — sometimes longer. And there were many times when Wayne feared he'd lost his son forever.

"I've had the phone call from the landlord that says, 'he's DOA, you gotta go down to the hospital and ID the body' — and he's back. He's just got a spirit that keeps coming through.

He's just got a spirit that keeps coming through. - Wayne Collins

"I believe in my heart that he is going to walk out of this," Wayne adds. "Some people go, 'Oh you are crazy — 20 years.' But that's part of knowing the whole person."

Over the years Wayne says many people have told him the best way to deal with his son's addiction is through "tough love." But he insists Kieran has taught him about a different kind of love.

"I think people who talk about tough love for addicts — it's the easy way out," Wayne says. "It's way harder to stay engaged and practice unconditional love, and show love for somebody who is lost."

A drop in the bucket

In the afternoon Kieran returns to the clinic to get his second shot of heroin.

"People get addicted to drugs," he explains. "They don't do them because they want to do them, they have to do them — like a frigging slave."

That's the reality for many people in Vancouver's Downtown Eastside.

According to statistics obtained by the Georgia Straight newspaper , a two-block area along Vancouver's East Hastings Street had more than 3,000 overdose calls in just two years. That's seven per cent of the entire province's 911 calls for suspected drug overdoses.

If anyone understands these statistics, it's the Crosstown Clinic's research coordinator, Kurt Lock. He has worked in the Downtown Eastside for 20 years.

When I walk with him through the neighbourhood, it's clear that most people know who he is. Lock explains that when you're the guy who can get people free heroin, it increases your popularity.

The Crosstown Clinic’s research coordinator, Kurt Lock, says the focus is on improving the quality of life of people dependent on heroin, and this has positive benefits for society as a whole. (Nick Purdon/CBC)

He says the 140 spots for patients at the Crosstown Clinic are "a drop in the bucket." To meet demand, he estimates they'd have to open five more clinics.

But is it really a solution to expand a program that gives out free heroin and doesn't push people to quit — after all, isn't heroin a poison?

Lock shakes his head. "If you have a clean, regulated supply, the drug itself it's not harmful for you," he says.

"I won't say it is good for you, but someone could live to be 100 years old and use heroin every day if it's not tainted with any contaminants."

I won't say it is good for you, but someone could live to be 100 years old and use heroin every day if it's not tainted with any contaminants. - Kurt Lock

Lock explains that many long-time opioid users look older than they really are because of what it takes to feed a street habit. Bad nutrition, homelessness and the contaminants found in street drugs are some of the things that hurt most long-time, chronic users.

Lock also counters critics who say health programs should be focused on getting people to quit rather than giving them the drug.

"The reason we provide heroin to people and we don't just expect them to quit is just that simply doesn't work," Lock says.

"We tried that for the last many decades … Why don't we put people in treatment? Well, we have done that. Why don't we put people in jail? Well, we have done that too. But the problem still exists."

Instead, Lock says the clinic focuses on quality of life.

The idea is to attract users to the clinic by providing them with the drug, and then once they are in a health care setting, try to address the issues that led to their dependence on narcotics in the first place.

Typically, the retention rate in opioid replacement programs that use methadone is around 30 per cent. In comparison, the Crosstown clinic's retention rate is more than 80 per cent.

Life without drugs

To supply a single user like Kieran Collins with heroin for a year costs around $27,000.

Proponents of the Crosstown program argue that this is cheap, because if Collins was getting his drugs on the street then society would pay twice as much through things like social, policing and hospital costs.

Toronto Public Health, for example, says "the social cost of one untreated person dependent on opioid drugs, which is attributed to crime victimization, law enforcement, productivity loss, and health care costs, is estimated at $45,000 a year."

Wayne has taken what he calls the more difficult approach of showing unconditional love for his son. 'I think people who talk about tough love for addicts - it’s the easy way out.' (Nick Purdon/CBC)

Beyond the financial costs, there's no escaping the fact that 11 Canadians die of opioid-related overdoses every day.

Collins says he sometimes runs into the mother of a friend who died, and it's a reminder of the human toll of street drugs. "I was there when he overdosed and died. She always kind of stops me and she's obviously mad because she's lost her son — but I think she kind of blames me."

Perhaps the most surprising thing Collins said during the two days I spent with him is that now his drugs are supplied to him, for the first time he's started to think of a life without them.

"I would like to know what it's like to live without having a vice of putting narcotics in my body every day," he says.

"I would like to know what it feels like, when I leave this world, to be in a clear mindset."