Coalmine would take 3.3bn litres of water a year from Sydney catchment, agency warns

WaterNSW says South32's proposal to extend Dendrobium mine could cause cracking in the walls of two dams

WaterNSW has objected to the expansion of a coalmine under Sydney's drinking water catchment because the project would cause unacceptable impacts, including the loss of 3.3bn litres of water a year.

The government-owned water corporation has also warned that mining company South32's proposal to extend the mining operations at its Dendrobium coking coalmine could cause cracking in the walls of two dams that supply water to the Illawarra and Macarthur regions, and may harm 26 endangered coastal swamps.