Conserving Water through Efficiency, Technology
Water is an important raw material for Alcoa, with our refining and ingot-casting processes requiring significant water resources. We work to ensure water efficiency across all of our operations, and we place an even greater focus on conservation in regions where water availability is most sensitive.
We adapt our approach to water accordingly in regions where drought is a problem. For example, we have evaluated a number of applications that might greatly reduce the evaporation of stored water in our Western Australia refining operations so that more is available for reuse. We also have evaluated secondary sources of water that can be used in our processes and still allow us to meet product quality requirements.
One challenge we face is that water-sensitive regions vary each year. In 2013, California, USA, experienced a grave drought, while Brazil had a worse-than-normal drought. Conversely, it was a good year for rainfall in Western Australia, which is normally a water-scarce region.
Our total overall use of freshwater was essentially flat in 2013 versus 2012. However, our freshwater-use intensity (consumption per unit of production) increased by 3% in 2013 compared to 2012 because some production capacity was taken offline. We have reduced this intensity by 22% versus 2005 levels, approaching our 2020 goal of 25%. This significant improvement is largely due to conservation efforts over the years at our Western Australian refineries and Intalco Works in the United States.
Cubic meters of water per metric ton of production
|Goal: 25% reduction||Progress: As of Dec. 2013 |
Total Freshwater Use
Millions of cubic meters
Total Freshwater Use by Region
Millions of cubic meters
Strategic Water Management
We believe freshwater is a valuable resource and must be used efficiently and effectively. It is our goal to employ qualified people, training, and state-of-the-art wastewater treatment equipment to achieve compliance with current and projected wastewater and stormwater discharge standards and to aggressively pursue the adoption of water standards and permit limitations based on sound scientific principles.
We continue to evaluate our water use within existing processes to determine where cost-effective reduction opportunities are available, and we assess water reduction, reuse/recycle, or elimination alternatives during the replacement or upgrading of existing facilities. For new plants, we determine the long-term availability of water resources and what restrictions exist or will be imposed on wastewater discharges.
Through our technology resources, we identify, develop, and deploy innovative solutions to address our opportunities and challenges. For example, we are using zero discharge systems whenever feasible. (See the Technology section below.)
In both 2007 and 2012, we completed a global water-risk survey that included an assessment of local and regional water stress. We cross-referenced location assessments with global assessments from the World Business Council for Sustainable Development (WBCSD) and the World Resources Institute to verify potential areas of stress.
Business and Stakeholder Collaboration
We are an active participant in WBCSD’s efforts on best practice sharing, technology sharing, and getting member companies focused on charting a worldwide sustainable water course. Specific focus areas include:
- Identifying strategic water risks/opportunities;
- Establishing a common understanding of the challenges facing businesses; and
- Enabling constructive engagement with wider stakeholders through business participation, a shared understanding, and a common language.
This business collaboration is aimed at addressing some of today’s water challenges:
- Rapidly rising demand due to many uses, more users, and expanding urban footprints;
- Tightening of more complex supply-demand balances;
- Increasing water stress and declining water quality; and
- Declining water security for more people, markets, and countries that is exacerbated by concerns regarding food, energy, and climate change.
In 2012, Alcoa Foundation initiated a partnership with the Carbon Disclosure Project (CDP) to develop a Water Management Leadership Index to rank publicly traded companies on their water stewardship and management of water-related risks. The water index encourages corporations to understand the supply chain’s exposure to water and other water issues that could substantially affect business operations, revenue, or expenditure. We continue to report into the CDP’s water disclosure system annually to track our progress and assist CDP in growing its information base.
We also work closely with our stakeholders to ensure that we fully understand all water-related risks and potential conflicts with respect to water and water use. We utilize the Alcoa Community Framework and the extensive stakeholder dialogue and consultation processes within it to ensure that we are appropriately addressing all potential water-conflict situations. Critical issues like water use and regional availability are prioritized according to the sensitivity of water among all potential stakeholders.
We continue to focus on the development, evaluation, and deployment of innovative and low-cost sustainable water management technologies and approaches. Such approaches focus on moving completely away from the conventional and more costly end-of-pipe water treatment technologies.
In addition to looking at production process changes to reduce the need for water, we are also focused on the use of significantly lower-cost natural-system applications for both water reduction and treatment. Such applications, which could cost up to 75% less than conventional technologies, include green roofs, water irrigation onto fields of grass and trees, engineered wetlands, and the use of various media for filtration of water contaminants, known as natural media filtration.
For the Ma’aden-Alcoa joint venture in Saudi Arabia, the partners developed a sustainable water vision for achieving the dual goals of zero process water discharge and 100% water reuse. In May 2013, the complex completed the installation of the Alcoa-developed Natural Engineered Wastewater Treatment (NEWT™) system to collect all sanitary and process wastewaters for treatment. Collected stormwater will be treated via an innovative activated alumina adsorption process. (Read the case study.)
The NEWT system uses a passive wetland environment to acclimate natural bacteria to remove and biodegrade organics from manufacturing wastewater, as well as bauxite residue to disinfect the treated effluent prior to its reuse in the manufacturing process. This waste treatment option is extremely cost-effective compared to traditional systems, which have high energy usage and operating costs, are maintenance-intensive, and often produce sludges or filter cake that must be landfilled.
We have partnered with Germany-based Bauer Resources GmbH, an engineering and construction company, to commercialize the NEWT technology and bring it to customers worldwide.
In 2013, we completed an engineered natural system (ENS) at our Alcoa Fjardaál smelter in Iceland that meets all government requirements and Alcoa criteria for stormwater treatment. The ENS comprises vegetation and engineered soil profiles over the entire site, as well as two constructed treatment wetlands that occupy approximately two hectares (five acres). This is the first full-scale natural treatment system for smelter stormwater in Alcoa and follows two successful pilots at our smelters in Massena, New York, and Mount Holly, North Carolina, in the United States. We also have a full-scale process wastewater treatment system at our Point Comfort Operations in the United States that is similar to the system at the Ma’aden complex.
Alcoa Plants Tap Non-Traditional Sources to Reduce Freshwater Use
Alcoa’s Natural Engineered Wastewater Treatment System Eliminates Wastewater Discharge, Reduces Freshwater Needs by 25% in Saudi Arabia
Innovative Wastewater Treatment System Reduces Costs, Reuses Bauxite Residue