Morwell River Diversion 

Precast arches being installed for the conveyor tunnels

Description of Works

Following extensive studies of the mine, Yallourn Energy realised that they would need to relocate the Morwell River by 2005 if they were to extend the life of the mine to 2032, and guarantee the life of the Yallourn W Power Station. An invitation to tender was extended to a number of companies in June 2000 for the diversion of the Morwell River around the Yallourn Open Cut.

RTL submitted a conforming design and construct tender which incorporated a range of innovative alternatives. The engineering alternatives offered by RTL provided the client with significant savings over a ten-year period and extended the life of East Field by approximately five years. These savings were achieved by redesigning the mine to exploit low strip ratio areas and by using overburden stripping as a source of fill material for an alternative Morwell River diversion alignment.

RTL's solution also ensured the preservation of significant wetlands, native vegetation and a number of cultural heritage sites that may have been affected by the initial proposal. This alternative also allowed the mining of coal reserves to the east of the East Field Mine, beneath the existing river diversion, extending the life of the mine and assuring a sustainable coal supply for the long-term operation of the Yallourn W Power Station. The innovation in RTL's tender resulted in the award of a four-year Alliance contract for the Morwell River Diversion.

Project Review

The Diversion of the Morwell River through TRU Energy's coal mine in the Latrobe Valley, Victoria, was completed as scheduled in May 2005.

The project, undertaken by the Roche Thiess Linfox Joint Venture under an Alliance contract with TRU Energy, was designed to extend the life of Yallourn’s Mine to 2032 and ensure a sustainable coal supply for the long-term operation of the Yallourn W Power Station, which provides 20% of Victoria’s power needs.

Project Scope of Work

The scope of work for the Morwell River Diversion included:

• Placing approximately 13 million m³ of engineered fill to form a 3.5 km river diversion embankment across the existing mine pit
• Constructing four tunnels under the river diversion, with a combined length of approximately 1.3 km for the conveyors to transport coal from the existing and new coalfields
• Completing associated works such as road construction, installation of drainage systems, instrumentation and other miscellaneous civil work
• Relocation of Services