Lake Nillahcootie is situated on the Broken River in north-eastern Victoria, 36km south of Benalla. The name Nillahcootie is of Indian origin and reputedly means ‘Blue House'.
The storage was built in 1967 by the Rural Water Commission as part of a program to assure water supply in northern Victoria.
Lake Nillahcootie was constructed to harness the flows of the Broken River to meet irrigation, domestic and stock, and urban water supply requirements.
In previous years when Lake Nillahcootie was assured of filling to capacity, water could be released in accordance with a target volume determined for filling Lake Mokoan. This operation optimised water harvesting between the two storages and would normally occur during winter and spring months. With the decommissioning of Lake Mokoan, this is no longer required.
The main spillway at Lake Nillahcootie features a unique Gothic arch-shaped crest that allows the discharge of 117,000 ML/d - equivalent to the volume of an Olympic-size swimming pool passing the spillway every two seconds.
The storage also features a secondary spillway that is operated only during severe floods. It uses the ‘fuse plug' principle, in which a section of earthen embankment within the secondary spillway (the fuse plug) has been designed so that at a predetermined flood level it will be eroded away and increase the discharge through the spillway.
Land and On-Water Management Plan
The Lake Nillahcootie Land and On-Water Management Plan provides a strategic approach to management of land and on-water issues at Lake Nillahcootie and was completed in March 2011. The Plan was developed in consultation with community, lake users, local government and other agencies. The intent of the Plan is to set out a program of simple strategies and actions to better manage the increasing pressures on the important values of the lake and its foreshore; including community awareness and involvement, recreation, public access and safe use, environmental and cultural heritage and public land management. G-MW will coordinate the implementation of the Plan over a 5 year period.