Upper Nepean Transfers

• Client: Sydney Catchment Authority
• Role: Advisory Services
• Cost: N/A
• Date: 2008 / 2009

The Upper Canal was built in the 1880’s and consists of over 44 kms of open canal, 16 tunnels (19 kms) and 10 aqueducts linking the Cataract, Cordeaux, Avon and Nepean Dams with Sydney’s Water supply at Prospect.

The heritage listed canal provides 15% of Sydney’s water supply and much of it is reaching the end of its engineering life. It is susceptible to stormwater and shallow groundwater contamination from intensive agricultural activities and animals and vehicles are known to fall into the Canal. Although fully fenced, there is an increasing level of illegal entry into the canal for swimming, rafting and vandalism.

TSA Management was engaged with business partners to identify optimum solution(s) to satisfactorily reduce the current and future risks to the SCA water supply system. TSA helped prepare a series of detailed Business Cases for the rehabilitation and replacement options for the Upper Canal. The business case was prepared in accordance with NSW Treasury Guidelines and assessed a number of options for protecting the heritage infrastructure while addressing water supply, security and mine subsidence issues.