The average time people wait in A&E at Watford has crept up by 15 minutes over the past two years.
The increase means during weekends the average wait now stands at more than two hours, while in the week it is only slightly less.
Though still within a four-hour target, the extra waiting time comes against a backdrop of A&E closures.
Betty Harris, chairman of Dacorum Hospital Action Group, said: “I’m concerned. It’s very worrying, the fact they are so short of beds.
“Although they are keeping within their limits it’s still not a good sign that the time is going up.”
In 2009 full A&E closed in Hemel Hempstead, to be replaced with an urgent care centre, and in January A&E at the QEII hospital in Welywn Garden City was similarly downgraded.
Betty said: “When you keep closing A&Es what’s going to happen? You’re going to flood other places.”
The figures, released under the Freedom of Information Act, show in 2009/10 the average wait at Watford was 1hr 35mins during the week and 1hr 48mins at weekends.
In 2011/12 the times increased to 1hr 51mins and 2hrs 1min respectively.
West Herts Hospitals NHS Trust has said the number visiting A&E has gone up 15 per cent in a year while the spend on temporary staff has doubled to more than £970,000.
Director of communications Liz Rippon said: “The trust continues to see an increase in the numbers of emergency patients. The trust is coping with this increase in demand due to our incredibly dedicated workforce, additional capacity and new ways of working, including a Clinical Decision Unit in the A&E department. The trust has increased its staffing levels in order to manage the additional capacity and ensure it continues to provide a safe, efficient service.”