A NEW Welsh-medium unit in Caerphilly is expected to start taking year seven and eight pupils by September this year.

The £20 million former St Ilan site is an extension of Ysgol Gyfun Cwm Rhymni near Blackwood, which would have been forced to turn away year seven pupils in September if Caerphilly council had not decided to expand elsewhere.

Projections show Ysgol Gyfun Cwm Rhymni, which has capacity for 1,448 pupils, will reach 2,423 pupils in eight years' time.

Last October Caerphilly council put in a bid to create the new 900-pupil unit, catering for ages three to 19, which is now being built on Pontygwindy Road, Caerphilly.

The site will accommodate "increasing demand for Welsh-medium secondary education", said the council's consultation document for the proposal.

Phase one of the development has involved upgrading the Phoenix building at the St Ilan site and creating a four-court sports hall.

The site is expected to be developed in four phases for secondary provision, with years 7 and 8 catered for by September this year; up to year nine by 2015; up to year 11 by 2017; and completion of the 900-place unit by 2018.

Staff will be employed at Ysgol Gyfun Cwm Rhymni and a limited number will be expected to travel between the two sites.

Despite this, projections show that by 2019, the Fleur-de-Lys site will once again be full, while in the rest of Gwent, the only Welsh-medium high school accepting pupils from neighbouring authorities in Pontypool will be oversubscribed by 2017.

A Welsh Government spokesman said they expect all local authorities to identify how they will provide sufficient and appropriate places, and the School Standards and Organisation (Wales) Act 2013 will place a duty upon local authorities to prepare, consult on and publish a Welsh education plan for approval by Welsh ministers.

As part of the bill, under certain circumstances, local authorities will have to "measure parental demand" for Welsh-medium education in their areas.