The Government has stated that inundation by sediment-laden flood waters would occur in the World Heritage Area for five weeks at a time [i]. Based on WaterNSW published flood levels, up to 4,700 hectares of the World Heritage listed Blue Mountains National Parks and 65 kilometres of wilderness streams would be inundated by the 14-metre dam wall raising [ii].

The wild rivers of the southern Blue Mountains form a landscape that has been largely untouched by modern society. The area is home to 48 threatened plant and animal species, ancient river valleys, rare dry rainforests and hundreds of Indigenous cultural sites [iii]. The significance of the southern Blue Mountains landscape led it to being inscribed on the World Heritage List in 2000.

The Regent Honeyeater is currently listed as Critically Endangered. The Burragorang Valley floor, to be inundated by the proposed raising of Warragamba Dam wall, is the most fertile regional habitat and key breeding site for this species [iv]. Impacts on one habitat (e.g. the Burragorang Valley) cannot be offset by improvements in another due to the rotational use of habitats by the species.

The lower Nattai Valley is home to one of Sydney’s refuge koala populations. The valley will be inundated by the raising of the Warragamba Dam wall raising.

[i] WaterNSW (2016), Warragamba Dam Raising Preliminary Environmental Assessment, page 24. Prepared by BMT WBM Pty Ltd, Sydney. Available online: https://bit.ly/2rzXjtz

[ii] WaterNSW (2016), Warragamba Dam Raising Preliminary Environmental Assessment, page 26. Prepared by BMT WBM Pty Ltd, Sydney. Available online: https://bit.ly/2rzXjtz

[iii] ibid

[iv] Ross Crates et al. (2018) Submission to the New South Wales Legislative Council’s inquiry into the Water NSW Amendment (Warragamba) Bill 2018, Inquiry into Water NSW Amendment (Warragamba Dam) Bill 2018. Available Online: https://bit.ly/2UsVs6F