It’s been three years since Shin Noh left his Coquitlam, B.C. home for his daily walk. The 64-year-old former pastor in the mid-stages of Alzheimer's disease strayed from his usual route that day. He was never seen or heard from again.

A member of his church reportedly spotted him that afternoon, but didn’t realize he was missing. Noh’s grief-stricken family believes an alert system - similar to Amber Alerts issued for missing children – could have rapidly spread word of his disappearance, and saved his life.

“Many more will go missing. My dad’s story isn’t going to be the only story,” Sam Noh told CTV Vancouver. “There are going to be other families going through what we had to go through.”

Canada’s aging population and the growing prevalence of neurodegenerative diseases that cause dementia could see more seniors wander away from their homes and families. Experts say half of those missing for more than 24 hours will suffer serious injury or death.

Over half a million Canadians are currently living with dementia, according to the Canadian Alzheimer Society. That figure is expected to reach close to a million in the next 15 years. More than 60 per cent of adults with Alzheimer’s disease or dementia will wander, according to researchers at the University of Alberta.

B.C. has the highest population of people older than 65 outside of the Maritimes and Quebec, according to Statistics Canada. That fact, combined with the province’s rugged terrain, is raising concern among search and rescue officials.

“Not finding him (Noh) represented a breaking point to me that there needed to be a way to handle these searches better,” said Michael Coyle, a search manager with Coquitlam Search and Rescue.

Appeals to provincial governments have so far gone unaddressed. NDP MLA for Coquitlam-Maillardville, Selina Robinson, introduced a private member’s bill urging the B.C. government to introduce a so-called Silver Alert system in 2014. In 2011, the Ontario government announced it was developing a program to help locate seniors with dementia who had gone missing. Neither has moved forward.

Roughly 35 U.S. states have Silver Alert systems run by state or local governments that go into effect whenever a senior, someone with Alzheimer’s disease, or dementia goes missing.

These programs circulate a description of the person through a combination of radio, television, and road signs on major thoroughfares. Some can send information to smartphone users in the area.

“We want to see a very narrow geographically targeted system because we know from statistics that people don’t wander more than about five or 10 kilometers away from the last place they were seen,” said Coyle.

In B.C., Sam Noh, Coyle, and Shawn Bouchard, whose aunt was found dead after wandering away from her care home in 2013, are moving ahead with a citizen-led stop-gap solution. The B.C. Silver Alert project shares news about missing persons via email, Facebook, and Twitter.

Sam Noh’s father was the subject of an unsuccessful large-scale search conducted by the RCMP, search and rescue officials, and hundreds of volunteers. Noh’s mission now is to help others make a difference in the crucial first moments when the next person goes missing by arming them with life-saving information.

“Our family has come to the conclusion that we may never find him again, but it’s obviously difficult to get closure,” he said.