Ross River Dam

Ross River Dam
Ross River Dam at night, with open floodgates, pictured in 2008.
Ross River Dam is located in Queensland
Ross River Dam
Location of the dam wall in Queensland
CountryAustralia
LocationBetween Kelso, Queensland and Mount Stuart, southwest of Townsville, North Queensland
Coordinates19°24′35″S 146°44′15″E / 19.40972°S 146.73750°E / -19.40972; 146.73750
PurposeFlood control, water supply
StatusOperational
Opening date1971
Dam and spillways
Type of damEmbankment dam
ImpoundsRoss River
Height34.4 metres (113 ft)
Length8,670 m (28,440 ft)
Dam volume5,085×10^3 m3 (179.6×10^6 cu ft)
Spillway typeControlled
Spillway capacity674 m3/s (23,800 cu ft/s)
Reservoir
Total capacity803,565 ML (1.76760×1011 imp gal; 2.12279×1011 US gal)
Active capacity233,187 ML (5.1294×1010 imp gal; 6.1601×1010 US gal)
Catchment area750 km2 (290 sq mi)
Surface area82,000×10^3 m2 (880×10^6 sq ft)

The Ross River Dam is a rock and earthfill-filled embankment dam across the Ross River, located between Kelso and Mount Stuart in the City of Townsville in northern Queensland, Australia. Built initially for flood control, Lake Ross, the impoundment created by the dam, serves as one of the major potable water supplies for the region.[1]

The dam reached 250% capacity in February 2019 as a result of mass rainfall and flooding in the area.[2]

Location and features

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The dam was constructed by Leighton Contractors[3] 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.[4]

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.[5][6][7][8]

Following a 2007 upgrade of facilities, the dam has a capacity of 250,000 megalitres (8,800×10^6 cu ft) and an earth rock embankment 8.67 kilometres (5.39 mi) in length and 34.4 metres (113 ft) high. The reservoir has a catchment area of 750 square kilometres (290 sq mi) with a controlled gated spillway. The reservoir has a current capacity of 233,187 megalitres (5.1294×1010 imp gal; 6.1601×1010 US gal) of water;[9] and can hold up to 803,565 megalitres (1.76760×1011 imp gal; 2.12279×1011 US gal) of water in flood mitigation.[10][11]

When the dam gates open, water spills over into the Ross River. Visitors may view the dam from a viewing platform at Ross Park. The Ross Dam Pump Station supplies up to 232 megalitres (8.2×10^6 cu ft) of water to the Douglas Water Treatment Plant, where the water undergoes aeration, sedimentation, rapid sand filtration and chlorination treatment before being pumped to the reservoir where the water is distributed to Townsville.[citation needed]

At the base of the dam and on the banks of the Ross River is Ross Park, part of Riverway, with facilities for picnics or barbecues, as well as public toilets at this location.[citation needed]

Upgrade of the dam wall

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  • 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.[1]
  • 2003 - The report confirmed that upgrades were required and by late 2003 because the dam moved 10 centimetres (3.9 in) 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 metres (11 ft) 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.[citation needed]
  • 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.[citation needed]
  • 2005 - John Holland Group and Macmahon are awarded the construction contract.[citation needed]
  • 2006 - Construction commenced with Constructing sand filters and supporting earthfill, extra rockwork to the dam embankment and the contraction of the gates.[citation needed]
  • 2007 - Project completed late 2007.[citation needed]

The spillway gates have increased the dam's capacity by around nine percent, which is about 21,000 megalitres (740×10^6 cu ft) or four months extra supply of water. Three spillway gates span the 40-metre (130 ft) 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 A$115 million.[citation needed]

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.[citation needed]

Water is supplied to surrounding areas by releasing water from the Burdekin Dam spillway into the Burdekin and Haughton Rivers. Weirs control the volume of water entering each river. The Haughton pumping station supplies water via a low pressure pipeline to Ross River Dam. The pipeline was built in 1988 by the Townsville Council. During the first decade the PVC sections of the pipeline repeatedly ruptured.[citation needed]

See also

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References

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  1. ^ a b "NQ Water (Upgrade project)". Archived from the original on 17 January 2008. Retrieved 6 February 2008.
  2. ^ Courier Mail: Rooftop rescues as gates of hell open. https://www.couriermail.com.au/news/queensland/weather/townsville-floods-rooftop-rescues-as-ross-river-dam-floodgates-open/news-story/db0fc048e13b16a6fcbc511dd3dc98a2 Archived 5 February 2019 at the Wayback Machine
  3. ^ Leighton Holdings history Archived 11 December 2007 at the Wayback Machine
  4. ^ "The Competing Influences of Deluge and Drought in Queensland's Dry Tropics". Environment & Society Portal. 5 February 2020. Archived from the original on 5 December 2021. Retrieved 14 July 2022.
  5. ^ "Ross River Dam". Townsville City Council. Retrieved 8 February 2024.
  6. ^ "Railway stations and sidings - Queensland". Queensland Open Data. Queensland Government. 2 October 2020. Archived from the original on 5 October 2020. Retrieved 5 October 2020.
  7. ^ "Mount Elliott (Special)" (Map). Queensland Government. 1942. Retrieved 8 February 2024.
  8. ^ "Queensland Globe". State of Queensland. Retrieved 8 February 2024.
  9. ^ "Paluma and Ross River Dam Levels". Dam and Water Storage Levels. Townsville City Council. Archived from the original on 16 February 2016. Retrieved 15 October 2015.
  10. ^ "Townsville Library on Twitter". Archived from the original on 8 April 2016. Retrieved 30 October 2017.
  11. ^ "Register of Large Dams in Australia" (Excel (requires download)). Dams information. Australian National Committee on Large Dams. 2010. Archived from the original on 12 December 2013. Retrieved 15 October 2015.
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