Barnsley Council insists there is no viable option other than to install a ring road around Penny Pie Park, almost five hectares of open ground off Dodworth Road where an existing crossroads has become a congestion blackspot.
But the project, which has already been approved and given planning permission, provoked fierce opposition with campaigner Peter Fielding elected as a Lib Dem councillor in May.
Cllr Fielding said the Save Penny Pie Park group would take legal advice on whether to challenge the council with a Judicial Review if the decision is taken push ahead with development.
“They are fully intending to push ahead with a Judicial Review and will start a crowd funding exercise,” he said.