Thirteen patients had to wait more than three hours on ambulance stretchers at Wagga Base Hospital because of a lack of beds and staff from June to August.
The new report from the Bureau of Health Information- which did not include Fridays or Saturdays - has provided new insight on internal health figures which said 27 per cent of ambulances presented to the department had to wait more than an hour to admit their patients in August.
NSW shadow minister for health Andrew McDonald said although Wagga was not as bad as other areas, it caused serious problems because ambulance staff are unable to leave until they offload their patients from the stretchers.
"Wagga is less of a problem than Wollongong which had 146 and Liverpool which had 140; however, those 13 patients all waited longer than acceptable," he said.
NSW Minister for Health and Minister for Medical Research, Jillian Skinner, said the problem was due to a lack of beds and they would be working to fix the problem.
"It is unacceptable for patients to be waiting for extended periods of time for beds to become available in the state's hospitals, including Wagga," she said.
"Part of the problem is that NSW Labor closed over 1500 beds across NSW ... that's why we're committing $215 million towards the $270 million redevelopment of Wagga Base Hospital, which will increase bed capacity from 237 to approximately 294."
Murrumbidgee Local Health District director of operations Jill Ludford said the hospital would increase non-emergency patient transport services and expand care for people with chronic illness to help ease demand on ambulances.
"Winter was a particularly busy time for the emergency department which experienced a 28 per cent increase in the number of patients in the highest urgency treatment categories compared to the same time last year," she said.
Health Service Union East regional organiser Mike O'Donnell said he was working closely with Wagga ambulance officers and the situation needed improvement.
"If proper resources and staffing were available we have no doubt that patient outcomes would be better and waiting periods would be better," he said.