The number of children with a special needs support plan has more than doubled in the last eight, driving up local authority funding shortfalls to 'unmanageable levels', according to council leaders.
A record half a million pupils have an education, health and care plan setting out their special educational needs, analysis by the County Councils Network shows.
The network says government changes announced earlier this year to address the growing crisis in the special educational needs and disabilities system will do nothing to 'stem the tide of demand'.
The analysis shows there are currently 517,026 pupils with special needs plans in England, more than double the total in 2015.
Last year, a record 66,356 children and young people started new EHCP plans according to the CCN, equivalent to an average of 182 children a day.
Liz Brighouse, CCN spokesperson for special educational needs and disabilities (Send), said that despite the government’s reforms package outlining some important changes which are beginning to be implemented, demand has continued to rise sharply.
'We remain concerned that these reforms will not stem the tide of demand that local authorities are facing, and whilst the legislative changes in 2014 were right in that they expanded eligibility and raised parental expectations, councils have increasingly been left to pick up the bill, which has increased their deficits to unmanageable levels.
'Action is needed urgently to address this, and we are calling on government to fully fund these reforms and ensure that councils do not continue to accrue significant deficits that would be impossible to pay down without insolvency.'
