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Best Practice Guide |
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Commercial Office Buildings |
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Water UseLandscaping and Outdoor Areas
Non-residential landscape irrigation accounts for approximately 7.5 percent of all urban water in California; residential irrigation uses another 27 percent of urban water. However, not all of this water is necessary to keep the grass green. Drip Irrigation To understand this, think of a plant as a person who must choose between guzzling a bucket of water in one sitting or sipping multiple glasses of water over time as their thirst dictates. Similarly, a plant can only consume a limited amount of water at any given time; excess water tends to run off and is wasted. Over-saturation actually drowns roots, causing plants to wilt and die. In sandy or gravelly soil, over-saturation can also lead to deep penetration where water moves rapidly past the root zone and is wasted. Another advantage of drip irrigation is the control over where water goes. Or, to put it another way, where water does not go. Pavements (and people) stay dry, weeds in adjacent areas are discouraged, and brown spots caused by uneven watering can be completely eliminated. This means less maintenance in addition to lower water bills. Even turf can benefit from drip subsurface irrigation systems. Drip is especially good for conquering such common lawn watering problems as awkward shapes and sizes, steep slopes, or narrow strips. Remote Controls and Evapotranspiration Regardless of the sophistication of a system, irrigation controls reduce maintenance time, require less water, and improve plant life - all of which saves money while enhancing the beauty of your landscape. Xeriscaping Parking Lots and Porous Pavement Porous, or permeable pavement, on the other hand, allows rainwater to penetrate paved surfaces and move into underground reservoirs. Eventually, this water joins natural groundwater, where it helps recharge local aquifers. Porous pavements cost roughly the same to construct as traditional pavements, and may even be up to 25 percent cheaper. Although the financial return for individual companies is relatively low compared to higher return investments, there are significant benefits for the local community. Porous pavements help treat water by filtering out pollutants before they enter the groundwater and fresh water resources. Porous pavements also lessen the need for curbing and help prevent storm sewers from overflowing. Drivers benefit, too, since these surfaces offer better skid resistance. Business ExamplesThe Natural Resources Defense Council installed porous pavement in courtyards and walkways, allowing stormwater to percolate into the ground instead of running down storm drains. Native plants used in the landscaping are watered with rainwater collected in one of two 1000-gallon cisterns. Swinerton, Incorporated, landscaped its rooftop garden terraces with native plants to reduce storm water runoff and solar heat island gains. Native plants require less irrigation water and help support local wildlife. Qualcomm, Incorporated, utilizes reclaimed water for its landscape irrigation. Landscaping also takes advantage of drought-tolerant plants and designs. Inside its buildings, Qualcomm has installed automatic shutoff fixtures at all sinks. Resources Morrison, J. and Gleick, P., Freshwater Resources: Managing the Risks Facing the Private Sector. The Pacific Institute, August 2004. Wolff, G., Cohen, R. and Nelson, B., Energy Down the Drain: the Hidden Costs of California's Water Supply. The Pacific Institute and the Natural Resources Defense Council, August 2004. California Integrated Waste Management Board, Xeriscaping: Establishing a Water Efficient Landscape. Detroit News, Everyone Undervalues the True Worth of Water. June 19, 2003. |