Maghull Labour Action Team's Cllrs Patrick McKinley and Lynn Gatherer are urging people from throughout the town to attend a public meeting on Friday to discuss the impact of plans to site a 'care village' on land at Damfield Lane.
Plans to build the facility on Damfield Lane were originally rejected by Sefton's Planning Committee after Sudell Ward Labour Councillor Patrick McKinley successfully argued for residents opposing the development.
The committee rejected the plans on the grounds that they encroached on urban greenspace.
But days after, the Tory-Lib Dem government changed the planning rules to allow developers to build on green belt and green space.
The developer immediately resubmitted the plans.
Residents and Maghull Labour Action Team are working to ensure that concerns about drainage, sewage and traffic are considered before Sefton makes its decision.
Cllr McKinley said: "Despite assurances from the developer regarding reducing the risk of flooding on the actual site, residents are still concerned about the potential wider social cost/increased risk of public health hazards to the area as whole as a result of the development, particularly the knock on effects on the sewage system.
"The sewage system in the area is fragile and subject to regular failure resulting in raw sewage being deposited into residents gardens in Hall Lane and seepage occurring from manhole covers in the area, exposing the public to potential health hazards.
"United Utilities have indicated that the existing drainage system is incapable of handling the current level of sewage, they cite that there is a major problem with hydraulic failure, by implication the polluting effects of such hydraulic failure will inevitably be made much worse for long suffering residents by the Damfield Lane development."
Cllr Gatherer said she feared for the heath of the local community.
Cllr Gatherer said: "The developer may well have put 'keep tanks' on their site for collecting surface water, but to ignore the ‘knock on’ effects on the sewage system and the potential health risks to the wider community outside the development is tantamount to being culpable in putting the health of the wider community at risk.
"United Utilities say the issue with the drainage needs sorting out, however, as it is a large expenditure and they cannot say when it will be remediated, it could be years and years. If this is the case residents feel that it is not right or proper to subject residents to ongoing intolerable living conditions that will be worsened by the Damfield Lane development if this goes ahead before the drainage problem has been resolved.
"The magnitude of potential pollution or health hazard is unknown, for instance if we have the waste of over 200 additional people being deposited on a daily basis into a failing sewage system and if we have a coalescence of surface water and tidal flooding the results could be very serious. Therefore a promise from United Utilities that this will be fixed in the future is not acceptable, this needs to be done to everyone’s satisfaction before any planning permission should be given."
Cllr McKinley said despite the addition of an 'educational theatre' on the land, the plans are identical to those originally rejected.
Cllr McKinley said: "These plans were rejected on the grounds that they development encroached on urban greenspace. The plans still encroach on urban green space.
"The only thing that has changed is the Tory-Lib Dem government amendments to the planning rules which allows developers to swoop in and grab our green spaces.
"This site is an area of natural interests with lots of species of wildlife making their home there. It is also part of a conservation area, and despite the addition of an educational theatre in the ‘swamp’, the developer has done nothing to ameliorate the reasons why the application was refused in the first place, which is the incursion into the green space."
The public meeting will be held to discuss the Damfield Lane plans on Friday (June 22) starting at 7pm at Maghull Town Hall.