Fine-Tuning New Power Generating Protocols Impact

February 22, 2000 Tumut & Adelong Times

The Snowy Mountains Hydroelectric Authority and the Department of Land and Water Conservation released 17,500 ML of water into Blowering Daft from Talbingo Dam via Jounama Dam and the Tumut 3 power station last Thursday as part of a trial to establish the effect of high release volumes on the water quality of Blowering.

The trials were carried out because in emergency situations such as those experienced recently by Victoria and South Australia, high volume releases of this nature may be required to generate electricity for NSW.

Higher than normal electricity consumption means the turbines must work at higher levels or for longer than usual. If one or more turbines around the state were to break down during this time, potentially some areas could suffer power shortages. Although the need for electricity would still exist, the ability to produce power would be reduced.

The Tumut 3 power station is able to generate emergency power. However, this means the releases of high volumes of water over short time frames may be necessary. In the past these releases have been made as required with little consideration of the impact on downstream water quality and ecosystems.

A commitment to sound environmental ethics in recent times means that these releases will no longer be made on an "as needed" basis. Instead a protocol restricting the volume of releases from Talbingo Dam has been developed through co-operation between DLWA and SMHEA to ensure the environment is protected at all times.

Last week's trial was necessary to establish whether the expected maximum volume releases would have an impact on the environment of Blowering Dam and the Tumut River downstream of Blowering. The release was within the normal operating range for Talbingo Dam and mimicked previous' releases as well as anticipating future needs.

With new hi-tech equipment, DLWC conducted intensive monitoring during and after the releases to determine impacts within the downstream of Blowering Dam.

Dr Helen Keenan of DLWC Leeton said after the release was made people might have noticed cool, turbid water passing through Blowering into the Tumut River. She said this may have affected the look of the river for a short time, with normally clear water "suddenly" dirty.

She said the dirty water would have little affect on the long-term habitat of the Tumut River and the environmental impact of the trial was expected to be minimal.

The trial is expected to produce results that will enable the SMHEA and DLWC to fine tune the operating protocols for power generation downstream of Talbingo Dam to maximise the capacity for power production and minimise the environmental impacts.