They're the last resort, but also the first people you call - police, fire and EMS - are increasingly relied upon even when they aren't exactly the right answer.

And when it comes to an influx of mental health calls all emergency responders are dealing with more than their share.

Until recently, every time a London police officer was called to a situation involving a non-violent struggle and mental health issues, EMS got involved, often transporting the resident to the hospital and waiting for the patient to be seen by a nurse.

Those wait times have been reduced considerably by a program at the London Health Sciences Centre (LHSC), but paramedics say they're still far too long, and they're going there far too often.

Over five per cent of ambulance runs are mental health calls that could tie up the vehicle and paramedics for hours.

Dustin Carter with Middlesex-London EMS says, "Emergency departments are often overwhelmed with mental health...When we transport these individuals to the emergency departments, sometimes our paramedics could be stuck on delay in the back hall, for hours, due to the capacity of hospitals in terms of mental health beds."

LHSC has 74 acute mental health beds and they are nearly always at or above capacity.

Mental health patients consistently make up about six per cent of all emergency room visits at LHSC, and many of those are repeat visitors.

Middlesex-London EMS has found that just 94 people in the region accounted for 1,082 EMS calls in a one-year period and more than half - 584 - were due to a mental illness.

Carter explains, "That reduces the amount of resources we have on the road to respond to other emergencies."

In 2014 there were several code zeroes - times when every single ambulance and paramedic was tied up on a call - meaning there were no staff able to take on other emergencies.

It's not all because of mental health calls, but it's part of the problem because patients suffering from mental illness don't have many options.

Don Seymour with the Canadian Mental Health Association - Middlesex (CMHA) says, "If you or I, for instance, were having an anxiety attack for stress, the only place you can go after the doctor's office is closed is the emergency room, its the default."

He wants to change that, and has proposed a 24-hour, seven-days-a-week mental health clinic.

"If you're having a minor mental health or addiction issue, you can just walk into this place. We've identified the location - it's on Huron Street, it's one of our administrative buildings - that we want to convert into the crisis centre."

He thinks it would cost just over a million dollars a year to operate and he's asked the Local Health Integration Network (LHIN) for funding.

It's something the LHIN says it's considering, although it hasn't been approved yet.

The CMHA has already been able to assist police and EMS in reducing time spent with residents suffering from a mental health crisis with its Crisis Mobile Team.

It's a team of mental health professionals who join police and EMS on mental health crisis calls.

"We show up and EMS doesn't have to put the person on an ambulance, doesn't have to take them to the ER and the person gets the right therapeutic intervention at the right time," Seymour says.

Last year alone, the 24-hour team attended 1,200 calls.

Kristi Bell of CMHA - Middlesex, adds, "We attend, police are still on the scene, we release them as long as there's no safety concerns and just take over for them."

It's too early to judge the impact the team will have on EMS, but London police say when the team is involved, officers are able to respond to other calls about two hours sooner.

Chief Brad Duncan says, "It's not just about time, it's not just about police dollars. It's about what is the best care continuum for these individuals."

And when it comes to mental health care, that means fewer paramedics and more therapists.

Coming up in part three: The impact residents suffering from mental illness have on the London Fire Department and why the city may be the first ever to have a fire inspector who focuses on hoarders.