10 WATER QUALITY PRODUCTS W ith drinking water becoming scarcer due to drought in highly popu- lated areas and drinking water sources becoming more polluted, both indi- vidual homeowners and businesses are becoming aware of the need for drinking water conservation. This brings to mind the old saying, “reduce, reuse, recycle.” While the thought of drinking recycled water may turn off many consumers, in a way we have been drinking recycled water for centu- ries. The water, or hydrological, cycle describes how water constantly changes between various states above and below the Earth’s surface, which is basically nature’s way of recycling. The mass volume of water on Earth is nearly the same as it was millions of years ago. It is the form in which the water exists, as oceans, rivers and groundwater, which varies over hundreds of thousands of years. While businesses may look into reducing water use and the possibility of reusing water in production, it is usually done as a cost-saving measure as water rates continue to rise. The average consumer may accept the rate increases or look for simple options to reduce their water use, such as turning off the faucet when brushing their teeth or installing water- saving devices like low-flow toilets. In drought-affected cities, there is a demand for water conservation that involves restrictions on lawn watering. The amount of freshwater that can be used for drinking is becoming more polluted, so we must act now to ensure clean drinking water. This involves conservation of current water resources and proper management of all water resources, which should include reducing the use of drinking- quality water in applications in which greywater or rainwater could be used instead. The cost of treating water to potable quality is higher, so we should use that water only for consumption. Non-potable water, such as rainwater and greywater, can be reused to flush toilets, wash cars, and water lawns and gardens. In an effort to reduce the amount of water used, some people may opt to collect rainwater for gardening purposes. Of course, rainwater collec- tion works best in areas with high rainfall levels. Some areas of the world, such as the island of Bermuda, rely heavily on rainwater collection for drinking water. In some areas of the country, collecting rainwater not only saves water, but also helps cities control storm water and the pollu- tion it may carry. Even in New York City, in a part of the U.S. that gener- ally receives more than adequate rain- fall to meet its needs, rain- water detention is mandated for new building projects above a certain size to help control storm water runoff. Matt Kaye, president of Better Waters, a water technology company that actively advises engineering firms and has supplied rainwater reuse technologies for numerous large-scale New York City projects, noted that there has been an expo- nential increase in demand for such systems as construction has returned to robust levels following the recent economic downturn. “Today, unlike before the Great Recession, we are seeing one high-end project after another, whether residential, commer- cial, hotel or mixed use, include rain- water retention and reuse,” Kaye said. “In fact, I think we are at the point that a majority of the most presti- gious new projects underway in New York City incorporate this conserva- tion measure: 99 Church Street, 56 Leonard Street, 855 Sixth Avenue and 205 E. 92 nd Street, for instance, are excellent examples. And part of our challenge [in] meeting the principles of sustainability is to design tech- nology sequences that minimize [the] power required to accomplish the goals of conservation.” Some cities or sewer districts offer financial incentives for home- owners and businesses by providing a discount on water and sewer bills for those who install rain barrels or rain gardens, or remove or reduce imper- vious surfaces, thus reducing runoff. The payoff can be substantial. In Austin, Texas, for example, businesses can earn up to $40,000 in rebates for installing rainwater harvesting and greywater reuse systems. Rainwater reuse also helps buildings qualify for LEED (Leadership in Energy & Environmental Design) credit, which is a certification for green building growing in popularity. Rainwater Treatment Because rainwater is raw and can pick up contaminants from the surface it runs over, it is a good idea to assess the water quality. The two biggest quality concerns with rainwater are particulates and microbiological contaminants. The intended use of rainwater dictates what treatment may be neces- sary. Rainwater that will be used in non-potable applications may not require treatment for microbiological contaminants, but would need filtra- tion to reduce particulates. If rain- water will be used for potable applica- tions, microbiological contaminants must be addressed. Microbiological contamination can occur easily as water runs from rooftops, which may contain animal excrement. Bacteria also can thrive if water sits stagnant for a period of time. Ultraviolet light is commonly used for rainwater disinfection, but other tech- nologies, such as ozone or chemical disinfection, may be used depending on regulatory requirements and the client’s needs. In some cities, rainwater that will be used for drinking requires a disinfectant that has a residual, like chlorine. It is important to become familiar with local requirements for rainwater collection and treatment before installing these types of systems. A New Era for Reduce, Reuse, Recycle Integrating water conservation strategies into water management By Marianne Metzger trends water reuse