The opening dates for four secondary schools being rebuilt have been cast into doubt after the harsh winter caused damage at the sites.

Integrated Bradford, the Local Education Partnership set up to deliver Bradford’s £400m Building Schools for the Future programme, said “every effort” was being made to find a way of achieving the original opening dates.

But Integrated Bradford appears to have stopped short of offering a guarantee that the schools would open as planned in Easter 2011.

As exclusively revealed in yesterday’s Telegraph & Argus, water inside pipes at each school froze, cracking the pipes and slabs laid over them as temperatures plunged. It happened as contractors filled the heating systems with water to test for leaks before they were covered in concrete.

The Telegraph & Argus asked Integrated Bradford what stage the assessment of the damage had reached; what delays the problems had caused and if the repairs would delay the opening of the schools, and what costs had been incurred putting the problems right? In a statement, its spokesman would only say: “Work is well-advanced in developing remediation and recovery plans, and every effort is being made to find a way of achieving the original opening dates. The costs associated with the current problem have not yet been fully assessed.”

A company called Educo, a consortium of Costain and Ferrovial Agroman, is responsible for the work. A spokesman for Educo said: “The construction activities being carried out at the time required the under-floor heating pipes to be full. The sudden drop in temperature rendered the task of emptying the pipes impossible. The affected areas are being rectified during the progress of the construction works and will not impact the quality of the completed schools.”

The sites are Grange Technology College and Hanson School, in Bradford, Beckfoot School, Bingley, and Greenhead High, Keighley.