Residents have demanded a fresh review of plans for a new village school after experts backed their concerns over flood risks.
Both the Environment Agency and Norfolk County Council’s own flood risk assessors have objected to the proposed development in Gayton.
County education officials say they are reviewing their timetable for the project, which had been expected to be completed next year.
But opponents say the whole scheme for land at the corner of Back Street and Winch Road should now be re-assessed.
Resident Geoff Gibling said: “It all proves how rushed this application has been and incorrect procedures and information has been used and submitted.
“It’s a completely flawed application on so many fronts.”
Officials from the Environment Agency and the county council’s own flood risk assessment unit have written to the authority objecting to the proposed development.
They said that flood risk assessments had not been done properly and “insufficient evidence” had been provided to justify the scheme.
The county council says it is discussing the concerns raised with the bodies.
But it has repeatedly insisted the proposed site is the most suitable available for a new school in the village.
The authority said it aimed to start building work by the end of this year when a formal planning application was submitted last month.
But the agency warned that it would be a “lengthy process” to address all of the issues raised.
A council spokesman said this week: “We keep all timescales under review as we move through the preparatory stages of a project.”
But objectors say lands near the current school site in Lynn Road represent a better alternative.
Mr Gibling said: “The county council must consider the other sites behind the current school, as these are more feasible.”