Residents in Denbighshire will soon be asked to provide proof of residency to use recycling parks due to increased use from outside of the county.
The centres at Rhyl, Denbigh and Ruthin have reported a dramatic increase in the amount of non-recyclable waste passing through the sites.
If the current trend continues, the disposal costs at the sites could increase by an additional £100,000 a year, says the council.
In a statement the authority says: "Staff have reported a marked increase in the number of people living outside of Denbighshire who are making use of the sites.
"To alleviate this issue, the council will be asking users of the sites to bring proof of residency with them, eg a driver’s licence or utility bill. Residents living in other counties will be asked not to use the facilities in Denbighshire, as the facilities are there for Denbighshire residents’ use only.
"Notices will be placed at the prks over the coming days, with the new way of working introduced from August 1."
Councillor David Smith, Cabinet Lead Member for Environment, said: “This decision has not been taken lightly and we do not wish to discourage any Denbighshire residents from using the centres.
“We have seen a marked increase in the number of people living in neighbouring counties making use of the facilities, to such an extent that it is adding additional costs to the taxpayers of Denbighshire. Based on the current trend, the disposal costs would increase by £100,000 a year. That is unsustainable and we need to protect the public purse.
“That is why we are introducing the new way of working, to discourage those living outside of the county from using facilities which are there for local people.
“We would like to thank people in advance for their co-operation."