The former Seanad leader believes the Government has chosen the date because people will be angry with the political system around budget time.
Under new EU rules the budget will be announced on October 15 this year – around the same time as the vote on the future of the Seanad.
"Everyone will be complaining about the bad budget and Enda Kenny will effectively be putting politicians in the village stocks for the public to throw rotten tomatoes at them," O'Rourke told the Herald.
O'Rourke is part of the Democracy Now group opposed to the abolition of the Seanad, but is campaigning for the upper house to be reformed.
She chaired the sub-committee on Seanad reform in 2004.
"The Seanad does not need to be abolished, it needs to be reformed," she said.
"To get rid of it altogether would be a diminution of the political system in Ireland, especially seeing as Phil Hogan has already got rid of town councils," she added.
The debate over whether to axe the Seanad could also be divisive for the government partners, with Labour's chief whip Emmet Stagg, as well as the party's Dublin Mid-West TD Joanna Tuffy, both saying they oppose the plan.
THE ABOLITION OF THE SEANAD HAS BEEN PROPOSED ON THE BASIS THAT THE UPPER HOUSE IS LARGELY INEFFECTIVE IN ITS CURRENT FORM AND COSTS &EURO;20M A YEAR.
However, opposition groups have argued that scrapping it would transfer all power to the Dail.