A Daventry District Council member has called for people to join a demonstration outside the town's civic offices to protest the Canal Arm proposal.
Having been granted planning permission in January this year, discussions on the Canal Arm project have moved on to funding which the council's Strategy Group will make a recommendation to the full council tonight.
The proposal will then need to be approved at a full council meeting of Daventry District Council members on July 27.
Labour's Ken Ritchie is opposed to the Canal Arm, and wrote a message on his Facebook page inviting like-minded people to join in the demonstration at 5.45pm before the meeting gets underway.
"The chances of it not being voted through at this stage are very slim, but there must be other Conservative councillors that would be very, very alarmed or at least concerned about this proposal." said Cllr Ritchie.
"£8million suddenly out of the reserves is a huge amount. I would argue that if we had decided as a council that we had nearly £9million to spend there should have been a proper discussion about what are our priorities.
Mr Ritchie suggested the money could be used instead to transform Bowen Square or to build affordable homes.
Chris Millar, Daventry District Council leader, said he had no problem with anyone demonstrating as they have a right to do so.
"I understand there are two viewpoints and people may have other ideas and that's fully understandable and acceptable, that's normal," he said.
When asked about alternative uses for any funding allocated to the Canal Arm, he said: "Whenever there is money involved people always have ideas what might be possible, what they might like to see.
"These things are never easy to actually deliver I can assure you of that, whatever they come up with.
"What I will say is that this is a long-term project, that this is the start of it. We have ways of getting this money in the longer term, we know that, and this is meant to drive economic activity in the Daventry area.