More than half of the drivers using a Preston hospital car park see it as a park-and-ride to get to the city centre – blocking spaces intended for patients and visitors.
More than half of the 541 spaces at the Royal Preston Hospital (RPH) are being used by people parking for longer than five hours.
Hospital bosses believe that many of them are commuters, paying the £1.50 daily rate and then catching a bus to avoid more expense parking charges in the city centre.
Evidence shows that 52% of drivers using the hospital car park stay for more than five hours. At Chorley and South Ribble, only around 30% of people are staying for more than five hours.
RPH parking chiefs are now looking into ways to target drivers using their car parks as an unofficial park-and-ride.
One idea is to introduce a two-tier pricing structure, with an increased cost for longer stays, but with exemptions for patients.
The measures are the latest attempts to resolve parking issues at RPH after Preston Council refused to grant planning permission for a new, larger car park.
At the beginning of July fines were introduced to deal with illegally-parked cars.
Ian Cox, director of facilities at Lancashire Teaching Hospitals NHS Foundation Trust, said: "People are parking on-site for between seven and eight hours.
"Figures show that most drivers park at Chorley and South Ribble Hospital for up to two hours, but then we have a spike with 30% staying over five hours.
"At Royal Preston Hospital this jumps to 52%, which suggests that drivers are taking advantage of our low, £1.50 daily charge. This means parking spaces for patients and visitors are being clogged up every day.
"Parking is already at a premium and if we are to improve the situation we need to root out these drivers and deter them from parking on-site."
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