Water
Access to water is critical to Rio Tinto's operations. We use water at every stage of our business - for exploration, mining, processing, smelting, refining, rehabilitation and drinking. We also use significant quantities of water to generate hydroelectric power.
Each of our operations has its own set of water challenges. Some are located in water-scarce environments where they compete with other users, while other operations need to manage surplus water from storms or groundwater. The quality of water is also a consideration, as it can affect production or increase operating costs. As a result, each of our operations implements our water strategy in its own way.
- Approach
- Risks
- Impacts
- Engagement
- Results
Water sources
The water we use in our operations comes from a variety of sources, including groundwater, surface water, seawater, water from dams on site or sourced from water treatment plants. About half of our water is marine water primarily used as cooling water at our power stations. We also use significant quantities of water to generate hydroelectric power, mainly for our Canadian aluminium smelters. The source and quality of the water changes from operation to operation. At many sites, we replace high quality (potable) water with poorer quality water to help conserve local water supplies.
Water withdrawn
As there is generally a higher community and environmental demand for freshwater than poor quality water, we consider how much freshwater we withdraw to be one of our key indicators for our water performance. In 2010, freshwater withdrawn increased by six percent to 516 billion litres, due to increased production, and high rainfall in eastern Australia.
Please see the Performance data page for a detailed breakdown of the types of water we withdrew by product group and location in 2010.
Recycled water
Water use increased in 2010 due to increased production at several businesses and high rainfall in eastern Australia. However, the amount of water recycled has also increased significantly (15 per cent) due to start of recycling at QIT Madagascar Minerals and higher production.
Note: our definition of "water use" changed in 2009 to exclude marine water; historic data is presented for consistency with previous reports.
Our water target
We have set a Group water target to reduce our freshwater use per tonne of product by six per cent by 2013 from a 2008 baseline.
Freshwater use excludes water that is extracted for ground control and discharged without use in our processes. The target is based on the combined performance of individual businesses.
During 2010, our freshwater use per tonne of product increased due to significant rainfall events in eastern Australia, which led to increased freshwater storage, and lower production or higher process water requirements at several businesses. These increases were largely offset by improved efficiency at our western Australia iron ore operations as production shifted to newer operations.
While many businesses have found a water target challenging to reach, it has helped drive water efficiency actions at operations, raise the profile of water and develop better data collection systems, baselines and projections across the Group.
