The Murrumbidgee River rises on the Monaro Plateau. The river initially flows southeast then turns north near Cooma and swings north-northwest through the ACT before entering Burrinjuck Dam near Yass. Burrinjuck Dam has a total catchment area of 13,100 square kilometres. Within the ACT are a number of other dams and gauging stations that are under the control of ACTEW. From Burrinjuck Dam, the Murrumbidgee River is joined by Jugiong and Muttama Creeks from the north and the Tumut River from the south, before emerging onto the western plains near Gundagai. On its route flowing west to Wagga Wagga, it is joined by other streams including Adelong, Billabong, Hillas, Tarcutta and Kyeamba Creeks.

The Tumut River is the largest tributary of the Murrumbidgee, rising in the Snowy Mountains. Within its headwaters are works that form part of the Snowy Mountains Hydro-electric Scheme including Tumut Ponds, Talbingo Dam and Jounama Pondage. Blowering Dam is located on the Tumut River just upstream of Tumut. It is outside of the Snowy Scheme and is operated by State Water Corporation. The major tributaries of the Tumut River below Blowering Dam are Gilmore, Brungle and Adjungbilly Creeks and the Goobarragandra River. The Tumut River joins the Murrumbidgee River just upstream of Gundagai.

The key findings of this review are set out in the Executive summary. Overall the various agencies worked effectively together to manage inflows and releases from dams that assisted in mitigating the height and extent of flooding downstream. There is a degree of tension between the operation of dams for water supply, electricity generation and flood mitigation:

• If the primary purpose is water supply then the goal is to keep the dams as full as possible.
• Electricity generation requires releases to be made from the dams.
• Flood mitigation can be maximised if there is airspace in the dams.

This review does not consider whether the current balance between these functions is the optimal balance. However in explaining the legislative framework it will hopefully enable an informed discussion of what the balance should be.