A critical incident has been declared at Lister Hospital in Stevenage today (Tuesday) due to "huge demand" on the emergency department, and roof leaks forcing ward closures.

According to NHS England, a critical incident can be declared "during times of extreme pressure", when a hospital is unable to deliver critical services, is experiencing incidents where patients' safety and wellbeing are at risk, is at OPEL4 - Operational Pressures Escalation Level 4 - and is in need of support from other health and multi-agency partners to restore normal operating functions.

The East and North Hertfordshire NHS Trust, which runs Lister Hospital, declared a business continuity incident on Wednesday last week, after heavy rainfall caused leaks in Lister's roof and forced the closure of wards 11A north and 11A south.

The NHS Trust said it was at OPEL4 - the highest level, meaning it was "experiencing severe operational challenges despite implementation of agreed action".

Today, Doctor Michael Chilvers, medical director at the East and North Hertfordshire NHS Trust, said: “Following a period of huge demand on our emergency department after the bank holiday, and our closure of two wards due to roof leaks following heavy rain, we have declared a critical incident at Lister Hospital.

"This allows us to call on additional support from our local NHS and care partners, to ensure our patients continue to receive high-quality care in a safe environment whilst we prioritise life-saving treatment.

“It is regrettable that during this time you may wait a very long time at Lister Hospital's emergency department, unless you have a life or limb-threatening illness or injury.

"The Urgent Care Centre at the New QEII Hospital in Welwyn Garden City is open from 8am to 10pm to treat minor illnesses or injuries, with a far shorter wait than at Lister.

"Alternatively, we urge the public to contact NHS 111 by visiting 111.nhs.uk or calling 111, who can direct you to the most appropriate care.

“Please be kind to our staff, who are working hard to treat patients as quickly as possible.”