Dublin City Council has said bin-raiding by people looking for bottles and cans cost it half a million euro last year, leaving already-collected rubbish strewn around the streets.
A briefing document said the Deposit Return Scheme, operated by Re-turn, had forced staff to clean up waste from city streets twice over.
Its waste management section estimated that three hours in every 24-hour cleaning cycle were being diverted to deal with "bin interference".
The document said the council had placed bin surrounds on receptacles to try and encourage people to deposit cans and bottles there.
However, these have had little impact and were instead being used for general litter disposal including coffee cups, drink cartons and cigarettes.
A breakdown of costs said Dublin City Council had spent more than €115,000 replacing locks on 'Big Belly' bins at a cost of €995 per receptacle.
The council had placed surrounds on a total of 110 bins at a cost of around €40,000, though this ultimately proved of limited use.
It said there were ongoing daily costs from the Re-turn scheme, with staff forced to remove torn bags, collect scattered waste, and return to areas already cleaned.
The briefing document said: "The estimated cost of this diverted staff and fleet time is approximately €351,000 per annum."
The briefing - prepared earlier this year - said costs for Dublin City Council were already in the order of €857,000.
And it predicted a further €351,000 bill for 2026 as staff would continue to be diverted to clean up already-collected waste.
The document said: "These figures are indicative but represent a reasonable estimate of the direct costs currently being incurred … and are likely to continue unless a solution is reached to this problem."
Dublin City Council said there were wider impacts including a "negative visual impact" on the streets of the capital and damage to the city's reputation and image.
It said litter created a reduced perception of safety and had a "potential impact on tourism and visitor experience".
The local authority acknowledged that the scheme had been successful on a wider scale, increasing recycling rates for plastic bottles and cans.
However, it said the impact in Dublin's city centre had been limited with "no significant differences" in street sweepings collected.
The city council said the objectives of Re-turn were good but that it was creating "significant operational challenges".
"The primary issue arises from the fact that returnable bottles and cans have become a monetary commodity, creating an incentive for individuals to recover containers from public litter bins," it explained.
The council said one suggestion would be to restrict access to deposit rebates to households with registered waste collection contracts.
However, it admitted this was not a perfect solution: "While this may reduce opportunistic scavenging, it would also limit access to the scheme for some members of the public."
The briefing was prepared ahead of a meeting between officials from the local authority and representatives of the Re-turn scheme earlier this year.
Dublin City Council included photos of bin surrounds stuffed with rubbish that was not recyclable under the scheme.
Asked about the records, the city council said they would continue to work with Re-turn to come up with solutions to curb interference with litter bins.
A spokesperson said: "In parallel, the City Council is progressing plans to remove the current derogation that permits the presentation of residential and commercial waste in plastic bags.
"Evidence has shown that this method contributes to ongoing litter and hygiene issues, as bags are frequently opened by individuals seeking deposit return items, in addition to problems caused by vermin and environmental exposure."
A spokesperson for Re-turn said: "Re-turn is having ongoing discussions with Dublin City Council and is collaborating with the Council. Our shared objective is cleaner streets, higher recycling rates and practical solutions that work for Dublin city.
"Re-turn has supported the installation of bin surrounds in Dublin city centre and in other areas across the country to provide a dedicated place for people to leave eligible containers when they are away from home, rather than placing them in general waste bins.
"Consumers are encouraged to return bottles and cans through the scheme to ensure they are recycled and deposits are refunded."
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