Town council and civic federation united in condemnation of plans for £50m warehousing and distribution centre at St James' Park.
Sawbridgeworth town councillors passed four resolutions, including asking East Herts Council why they were not consulted on the centre plan.
Education authority Herts County Council has chosen ISG to construct the new campus off Whittington Way.
Proposed distribution park "could not be in a worse location" and its impact on town's congested road network would be "catastrophic".
Bellway will build 119 houses and 12 apartments for private sale, plus 88 affordable properties for rent or shared ownership at St James' Park.
The town council has published proposed revisions to its two neighbourhood plans after consulting the public.
Indie GreenWatch columnist Louise Tennekoon: "I am not arguing against development. I’m arguing for thoughtful custodianship of nature."
A grade II listed barn at Foxdells – formerly the home of ARC, Animal Rescue Charity – is at the heart of the the ambitious scheme.
The scheme is earmarked for the heart of developer Countryside's 750-home Bishop's Stortford South estate, St James' Park.
Thorley Parish Council is championing residents living next to the construction site by calling for work on part of the development to stop.
The 900-place campus, straddling the A120 bypass, will serve students living on the Stortford Fields and St Michael's Hurst estates.
The district council's development management committee approved the scheme for The Bishop's Stortford High School despite fierce objections.
The town council has organised a Covid-safe consultation event in Jackson Square on Thursday and Saturday (Nov 5 and 7).
Bishop's Stortford High School development will follow construction of new secondary off Whittington Way which is set for completion in 2022.
Developers consortium and county council seek permission to build on site formerly marked for one of three primary schools for Stortford North.