Ross River Dam

Location and features

The dam was constructed by Leighton Contractors in 1971 for the purposes of flood mitigation and water storage. The dam was an attempt to address Townsville's dual water concerns--abundance and scarcity--and added to the city's long history of attempting to tame the natural environment.

In the 1980s, the second stage of the dam necessitated a deviation of the Flinders Highway and Mount Isa railway line (which previously ran straight north-south) to be further east. This was completed by 1986 and resulted in the closure of Toonpan and Barringha railway stations on the removed route; they were not re-established on new route.

Following a 2007 upgrade of facilities, the dam has a capacity of 250000 ML and an earth rock embankment 8.67 km in length and 34.4 m high. The reservoir has a catchment area of 750 km2 with a controlled gated spillway. The reservoir has a current capacity of 233187 ML of water; and can hold up to 803565 ML of water in flood mitigation.

Upgrade of the dam wall

Timeline of the upgrade:

• 2001 - a panel of experts in dam safety and construction undertook an investigation of the dam. Over two years, the panel conducted studies of the dam's compliance with world standards.
• 2003 - The report confirmed that upgrades were required and by late 2003 because the dam moved 10 cm a year. At that rate, the dam would have burst in a 10-year period, causing the whole suburb of Kelso to be inundated. The first stage of lowering the spillway by 3.5 m was underway, the lowering of the existing spillway has been done so the installing of dam gates to control the flow downstream and water storage levels can begin.
• 2004 - A combined GHD-MWH team was appointed to design the remaining work and manage the project. The contracting strategy was the first application of the 'Early Tenderer Involvement' (ETI) procurement model, developed by consultants ITN.
• 2005 - John Holland Group and Macmahon are awarded the construction contract.
• 2006 - Construction commenced with Constructing sand filters and supporting earthfill, extra rockwork to the dam embankment and the contraction of the gates.
• 2007 - Project completed late 2007.

The spillway gates have increased the dam's capacity by around nine percent, which is about 21000 ML or four months extra supply of water. Three spillway gates span the 40 m wide spillway. The upgrade was going to take until mid-2008 to complete unless rainfall delays construction, however it was completed ahead of time in late 2007. The cost was around 115 million.

The dam's storage was temporarily reduced with the lowering of the spillway to make way for the new floodgates that have now been fitted.

In 2019 there was major floods and the dam reached the highest capacity it ever has at 232.79% which caused the 2019 Townsville flood.

References

References

1. "NQ Water (Upgrade project)".
2. [http://www.leighton.com.au/about_us/history/history.html Leighton Holdings history] {{webarchive. link. (11 December 2007)
3. (2020-02-05). "The Competing Influences of Deluge and Drought in Queensland's Dry Tropics".
4. "Ross River Dam". Townsville City Council.
5. (2 October 2020). "Railway stations and sidings - Queensland". [[Queensland Government]].
6. (1942). "Mount Elliott (Special)". [[Queensland Government]].
7. {{Queensland Globe
8. "Paluma and Ross River Dam Levels". [[City of Townsville.
9. "Townsville Library on Twitter".
10. (2010). "Register of Large Dams in Australia". [[Australian National Committee on Large Dams]].
11. "Ross River Dam". Townsville City Council.
12. "Mayor welcomes IGEM report findings". Townsville City Council.