On a recent day in the County of Essex in southwestern Ontario, there were no ambulances available to respond to emergencies for almost three hours as 26 paramedic teams were delayed at hospitals, highlighting an "unsustainable" issue seen provincewide, officials said Monday.

The county declared a local emergency Monday due to long — and increasing — waits for ambulances to offload patients at hospitals, which means they are unavailable to go on other calls.

Last Wednesday, Essex-Windsor EMS was in code red status, in which only two ambulances are available, and then went "quickly" into code black, when no ambulances are available, for about three hours as all 26 "rostered" ambulances were delayed at hospitals, officials wrote in a statement.

Neighbouring ambulance services have historically relied on each other for support when one community has higher-than-normal call volumes, but that same day last week there were between zero and seven ambulances available to cover the region "from London to the Detroit River between lakes Erie and Huron," officials wrote.

"Our paramedics and our hospital partners are doing everything they can to respond to this crisis but the causes are complex and related to longstanding systemic issues including hospital capacity, patient flow and a lack of available local primary care providers," Essex-Windsor EMS Chief Bruce Krauter said in the statement.

"This is unsustainable."

Windsor Regional Hospital issued its own statement Monday, saying higher-than-normal patient volumes there were contributing to offload delays.

As of Monday morning, the occupancy for medical/surgical patients at its two campuses was at 106 and 107 per cent, the hospital said. As of 9:45 a.m. there were 44 patients combined in both emergency departments who had been admitted but were waiting for an in-patient bed to become available.

"WRH is anticipating additional patient volumes as flu season and any resurgence in COVID-19 cases arise this fall," the hospital said in the statement.

The Essex-Windsor EMS chief and county officials are calling on the province to create incentives for hospitals to meet 30-minute offload targets, require hospitals to triage patients brought in by paramedics as a first priority, and allow low-acuity patients to wait by themselves in the emergency room.

Earlier this year, the Ontario government issued a memo to emergency services, telling them to consider having paramedic crews tend to more than one patient at a time in ERs — known as "batching" patients — so that paramedics could return to service more quickly.

Offload delays have been worsening in many communities across the province, and the president of the Ontario Paramedic Association said this summer that they have gotten 12 times longer in the last year alone.

The County of Essex says the frequency and duration of offload delays has risen sharply since 2020, with ambulances idling outside emergency rooms waiting for the patient to be admitted for sometimes longer than 12 hours.