An extension to road closures around the new Katherine Warington School in Harpenden will not affect the opening date for pupils.
Roadworks around the edge of the school site, off Lower Luton Road, were due to be completed by September 22 but have since been delayed by a further five weeks.
The roadworks include temporary traffic lights at the Common Lane and Crabtree Lane junction, and improving access to the school site by lowering the bank, building entrances, installing drainage and streetlights, constructing a lay-by and bus stop and modifying the kerb line.
A statement from campaign group Right School, Right Place, which has long maintained the site is inappropriate for development, said: "A further five-week delay appears to have been quietly introduced via road signage and online road work notices, with no discernible communication to local residents.
"This begs the question of whether and when the school will actually be open, and how the area will be safe for pupils, staff, through-commuters and local residents, with roadworks that are now extending weeks beyond the start of the academic year and into half-term."
Building work at the school itself will see the sports centre converted into temporary classrooms, with construction due to be completed on Thursday, September 19.
READ MORE: Pupils must travel to Hatfield after further delays to Harpenden secondary school
At the start of term pupils will travel to the Law Court Building at the University of Hertfordshire campus in Hatfield for lessons, with transport provided at no cost to parents, until the school site is ready.
Headteacher Tony Smith said: "A recently approved amendment to planning changed the phasing of some work to the roads around the school site which will now be undertaken after the school is open to its initial cohort in September.
"Some of that work will require an extension to the road closure programme which is why the roadwork notification signs have been altered to reflect this. "This will not cause a delay to Katherine Warington School opening. We remain on track to welcome our pupils on September 5 at the University of Hertfordshire, take possession of the Phase 1 build on September 19 and teach our students on the Lower Luton Road site from Monday, September 30.
READ MORE: Harpenden drivers warned of 'significant delays' for Katherine Warington School roadworks
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