One in three people worldwide lack enough water to meet daily needs, according to the World Health Organization. The problem is getting worse as populations grow.
We are committed to minimizing our impacts on water quality and availability in the areas near our operations. Our water strategy takes into account:
The total quantity of water used
The water source, e.g., rainfall or aquifer
Local levels of water stress
Our manufacturing processes use a considerable amount of water. By 2015, our goal is to reduce our total water usage by 25 percent from 2007 levels. We are focused on consuming water more efficiently in our production processes and general use.
We systematically track the water source of every site – whether it comes from the municipal supply, ground water, surface water or captured rainwater. When calculating our performance against our short-term water use reduction goal, we focus on freshwater withdrawals from municipal supplies and ground water.
We are finalizing a tool developed with the University of Arkansas and The Sustainability Consortium to assess the severity of water impacts at each site. This tool takes into account the status of local water resources, our usage, the quality of our discharges and the share of water usage in the industrial sector and will be published in a peer-reviewed journal. As we continue to develop our long-term strategy, we will use this tool to set differential targets by watershed and facility.
Wrigley’s factory in Plymouth, U.K. captures about 2,000 m3 of rainwater each year, enough to supply a third of the water needed for its cooling towers. This saves money and reduces energy use associated with air-conditioning. In Asquith, Australia, Wrigley implemented a similar project – capturing rainwater for all onsite hard surface washing, use in restroom amenities and to supply the cooling towers. The result is a 35 percent reduction in water consumption from the grid, which saves 3,600 m3 annually.
Mars Drinks’ National Office in Basingstoke, U.K. has installed a rainwater harvesting system, reducing water consumption from the grid by over 40 percent. The project has been such a success we are evaluating the feasibility of installing similar rainwater harvesting systems at our West Chester, Pennsylvania, U.S. factory.
Mars Petcare, Birstall, U.K. installed a 240 m3 rainwater collection tank to supply water to its bio-filtration process. Bio-filtration is used to control odor from ovens. Air from the ovens passes through a thick layer of pine chips, and enzymes within the chips remove bacteria and other waste particles. Based on the site’s average rainfall, the project is estimated to reduce the water needed for bio-filtration by up to 60 percent, saving almost 5,000 m3 per year.
Mars Chocolate, Chicago, Illinois, U.S. installed a new cooling tower and belt-washing system, which, coupled with behavior changes, resulted in an 11 percent (37,000 m3) annual reduction in water use. In total, the site has reduced its water consumption by 31 percent (127,000 m3) since 2007, while production volumes have increased by 12 percent.
Our long-term objective is to cause zero degradation of water quality. We typically treat our wastewater so it is clean enough to discharge into municipal wastewater systems, where it receives further treatment.
Improving the quality of our wastewater is as important as reducing the volume discharged, because reducing volumes can actually increase the concentration of waste within it. We test wastewater quality periodically but need better systems to monitor the volume we release. Many water utilities only measure the amount of water used, not wastewater discharged, so our data on wastewater released is incomplete. We are installing meters to capture our own data directly.
Our Petcare facility in Mogi Mirim, Brazil, is the first Mars operation to develop a water self-sufficiency program. This program involves a combination of conservation, reuse, rainwater capture and an onsite well. These measures save some US$626,000 per year.
The main savings come from reductions in water use, treatment, and the transport and disposal of solid waste generated during treatment.
Wrigley factories across Asia manage their own wastewater treatment. The treated water is reused for on-site amenities and lessens the burden on municipal treatment systems.