A report into new sewage infrastructures on the Muston Road development fails to offer any assurances over safeguarding against flooding, according to Filey Flood Working Group.
The warning comes after the publication of a Yorkshire Water study on Monday which stated a pipe could be fitted in the 300 home proposals that would cope with 250 litres of water a second.
The report also said that the sewer, planned to sit around 1.2 metres below the ground and take water along Martin’s Gill and down Martins Ravine, would not cause instability on the land and produce no scouring of the beach.
It added: “It is unlikely that a sewer laid to this depth and size would cause slope instability and construction would be relatively quick.
“However, it would be prudent to carry out some slope stability works prior to construction to confirm buildability.”
A final and more detailed report in expected in March.
However, Cllr John Haxby was somewhat vociferous in his damnation of the study and was worried Martins Ravine would be significantly damaged with traders subsequently feeling the pain.
He said: “Anybody worth their salt can read a book and look at a flow to determine what size pipe will carry the flow.
“The poor traders at the bottom have already suffered two seasons of loss and they really do not need more.
“The developers have had plenty of time and I would have liked to see a lot more meat on this report.
“We know that the ravine is highly unstable and its condition is unknown.”
Cllr Sam Cross, who has previously criticised the plans for being too large for Filey’s infrastructure to cope with.
He said he was also extremely disappointed with the report’s findings and its late publication, which came so close to the borough council’s planning decision.
He said: “I am concerned that it has been done as a rush job.
“There are concerns about the effect on the beach and the scouring which I don’t think this covers sufficiently.
“There is nothing different in this report and it does not confirm anything conclusive or different to say that it will be okay going forward.
“We have just got the Blue Flag back in Filey and we don’t want to see sewage going into the area which will have a big effect of tourism.”