TORONTO - The head of Toronto's public workers' union says the city's plan to begin privatizing garbage collection will cost taxpayers more, not less.

Mark Ferguson, president of CUPE local 416, says the move is an ideological attack and cited studies that suggest contracting out waste collection will end up costing more.

City officials today informed the union they are recommending bids be sought for trash collection west of Yonge Street to Etobicoke, where garbage is already handled by private contractors.

Mayor Rob Ford promised to privatize garbage collection during last October's civic elections, saying it would save millions.

His cost-cutting agenda helped him win the mayor's chair in Canada's most populous city, where a six-week civic workers' strike in 2009 resulted in mountains of rotting trash.

Ferguson says the data used by Ford to support contracting out the service is based on "fuzzy math."

He says public delivery of services is a better deal for Toronto residents.

The city, in its notice to the union, also recommends bids for "contingency collection services" anywhere in the city, as well as two litter and recycling programs.

Officials say the written notice meets the city's obligation under the collective agreement to provide three months' notice of its intentions.

The recommendation will go to the public works and infrastructure committee April 26 and before council May 17-18. If approved, there would be no change until mid-2012.