A second school with capacity for around 700 pupils will be needed to cater for Dargavel Village, Renfrewshire Council has confirmed.
Talks have been held with landowner BAE Systems about securing land for the facility, while councillors will be asked to give officers the green light to move forward with the plans at next month’s education board.
A statement has been released after further analysis suggested space could potentially be required for as many as 1,500 in the area by 2033.
It was estimated the current roll of 463 at Dargavel Primary School could rise to around 600 to 620 by August and further to between 685 and 705 the year after that.
The building in Arrochar Drive, Bishopton, had a preferred maximum of 548, although previous sums predicted the register would not exceed 430.
Council chiefs apologised for the blunder, pledging to fix it, and as a result six modular classrooms – with room for up to 198 pupils – will be introduced at the site over the summer break.
Steven Quinn, director of children’s services, updated parents and carers about the proposed “long-term solution” on Friday.
He said: “We can now confirm we intend to recommend building another primary school within Dargavel.
“Members of the council’s education and children’s services policy board will be asked to give approval for us to progress work on a new school at their next meeting on March 9.
“The new school will require capacity for around 700 pupils.
“As part of our long-term planning, we will develop further options to give us the flexibility to increase primary school capacity in the wider area, should it look likely to be needed.
“We are already in discussions with the landowner BAE Systems over securing land within the Dargavel development for a new school and will continue that as a priority.
“We estimate the project to design and build a new school will take around 36 to 42 months, from start to finish.
“We will provide a firmer timeline for this once the site of the new school is agreed.”
The botched calculations sparked severe criticism from the parent council and opposition councillors.
A review has also been ordered in the search for answers over the error.
Councillor Iain Nicolson, leader of Renfrewshire Council, said: “We understand the concern expressed by parents in the Dargavel area over school capacity.
“I can assure them our full focus is on getting the right solution for local pupils, which is why officers are now able to progress plans for a new school in the area.
“A significant error was made when planning the current school and the circumstances behind this are now subject to an external review.
“Throughout the process, engagement with the school parent council and wider parent community will be crucial – and we will ensure their views are sought as we develop future options.”
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