One year on, Morwell river diversion rebuild well progressed

Work to rebuild the Morwell River Diversion is nearing completion, with the river expected to be flowing at the Yallourn site later this year.

The significant recovery and re-establishment process has so far involved thousands of work hours and the expertise of hundreds of workers.

The work follows the failure of the Morwell River Diversion on 6 June, 2012. The failure involved water breaching a tunnel under the diversion, damaging infrastructure and causing river water to flow into the open cut mine.

Group Executive Manager, Operations and Construction, Michael Hutchinson said the work had been complex but was well progressed.

“This has been a massive task that has involved the skills and expertise of hundreds of people,” Mr Hutchinson said.

“The resourcefulness and dedication shown by everyone involved has been extraordinary and has allowed us to progress this work quickly and safely.

“Designs for a permanent repair are completed and include added design features such as a complex liner system and extra drainage to provide added protection to the new Morwell River Diversion.”

The Diversion reinstatement work is being overseen by two full-time inspectors.

“The specialists engaged to develop plans for the Diversion have incorporated all possible scenarios into the new peer-reviewed design,” Mr Hutchinson said.

The 800 metre liner system, involving nine different layers, has been double seamed welded, with each joint sent away for quality testing.

The work has also involved:

• More than 150,000 hours of work since January; and
• More than 1.3 million cubic metres of material such as clay being excavated or used as backfill;

The diversion is expected to be completed by September, but work continues to be weather dependent.

“While we are nearing completion, there is still some significant work to be done. Wet weather makes vehicle movements and work conditions difficult and this will impact the exact timing of opening up the diversion.” Mr Hutchinson said.

“The most important task for everyone involved is to complete the work safely.”