Most of Belfast's water is supplied via the Aquarius pipeline from the Silent Valley Reservoir in County Down, created to collect water from the Mourne Mountains. The rest of the city's water is sourced from Lough Neagh, via Dunore Water Treatment Works in County Antrim. The citizens of Belfast pay for their water in their rates bill. Plans to bring in additional water tariffs have been deferred by devolution in May 2007. Belfast has approximately of sewers, which are currently being replaced in a project costing over £100 million and due for completion in 2009.