Major Projects

What's in place?

Re-instating Cotter Reservoir as part of our water supply

The Cotter River catchment is part of Namadgi National Park and lies completely within the borders of the ACT. The river itself starts high up on the Brindabella Mountains and is fed by melting snow and rainfall. Corin, Bendora and Cotter dams are part of the Cotter River catchment, which is heavily protected from outside activities that may affect water quality.

The water from this catchment is of good quality, although the catchment suffered severe damage during the January 2003 bushfires. The loss of vegetation in the catchment means that the quality of water running off the catchment could be more variable. Immediately after the fires, there was an increase in the turbidity (cloudiness) and associated iron and manganese in the water flowing into the three Cotter River reservoirs.

Water stored in the highest dam, Corin, is released into the Cotter River to control the level of storage in Bendora dam. From Bendora, a large diameter pipeline brings the water by gravity flow to the treatment plant on Mount Stromlo at the western edge of Canberra. The Bendora gravity main is 20 kilometres long and has the capacity to carry 310 million litres of water per day.

In December 2004 the Cotter dam was brought online in response to the ongoing drought. The water from the Cotter dam had not been used in recent years and was held as a drought reserve. Water from the Cotter dam is pumped to the Mount Stromlo water treatment plant, blended with water from Bendora supply, and treated for supply to Canberra.