Quick-responding ambulances are crucial for health emergencies, but the region faced high demand on Monday.

As many as a dozen ambulances were reported waiting at the Cambridge Memorial Hospital at different points during the day.

“You can’t stop people from calling 911. That’s not going to happen,” said Luke McCann, president of the Canadian Union of Public Employees.

The region’s paramedic service was in and out of code red all day, meaning there were not enough ambulances for the calls coming in.

When that happens, the next closest ambulance in a county or municipality responds.

This can sometimes mean ambulances coming from Perth, Brant or Guelph-Wellington, and response times of 30 minutes or more.

Code red also impacts paramedics. They can face shift overruns, long hours and burnout.

According to the union, off-loads are one part of the puzzle. An increase in calls is another.

“That’s only going to get worse as our population ages, and we’re one of the fastest growing regions in the province, so we can’t keep up with this anymore. It’s just going to continually get worse every year,” McCann said.

The union representing the paramedics and fleet staff for the Region of Waterloo said that the region’s 2016 master plan for paramedic services needs to be revisited.