More than $1 billion will be spent on child protection, homelessness and disability services in NSW in 2014/15 as the state government seeks to deliver on its “obligation to help those in need” in its last budget before next year’s election.

Western Sydney has also emerged as a potential big winner with infrastructure promises including $400 million for the first stage of a new Parramatta light rail network.

In his first budget as Treasurer, Andrew Constance has announced an additional $500 million will be spent over the next four years on child protection.

The money will assist the transition of children from out-of-home care to the non-government sector, support caseworkers and deliver an IT system upgrade.