State of the Planet

News from the Columbia Climate School


New Water-Smart Communities Prepare For a Water Scarce Future

A recent study by the Stockholm Environment Institute warns that the American Southwest is exhausting its water resources, and if water use isn’t reduced, “The cumulative water shortfall for the Southwest for the next century, without adaptation, will be 1,815 million acre feet” due to population and economic growth. Climate change will, of course, make things even worse, and water scarcity won’t be limited to the Southwest. The study recommends that conservation and efficiency measures be implemented without delay. Leading the way, a few forward-thinking developers have already created new water efficient residential communities that are poised to meet the water challenges of the future.

Sterling Ranch

Sterling Ranch, a 3,400-acre community in Douglas County, Colorado, was designed and planned with water efficiency and sustainable use of water resources in mind. It will use 1/3 of the water Douglas County traditionally requires its developers to provide, making it Colorado’s most water efficient community. Recently given the go-ahead, the $4.4 billion project will construct 12,050 new housing units over the next 20 years. The condos, townhouses, and medium and large homes will range in price from the low $100,000s to $750,000 and up. Characterized by close-knit villages, the community will include schools, 37% open space, and 30 miles of trails for biking, hiking and horse back riding.

Sterling Ranch will achieve its goal of 1/3 water use through an array of strategies. The goal is for each residential unit to use no more than .286 acre-feet or 93,200 gallons of water per year (255 gallons a day), including both indoors and outdoors. Homes will be outfitted with water efficient toilets, faucets, showers, washers and driers. The outdoors will limit landscape areas needing irrigation, and feature native plants that require less water and efficient irrigation systems. Residents can choose how they want to spend their water budgets, selecting from various waterwise plantings or an edible garden. Common areas will also use water-saving plants, with artificial turf on most ballfields. Previously, rainwater harvesting was illegal in Colorado, but Sterling Ranch was the first development chosen as 1 of 10 pilot projects for Colorado’s rainwater harvesting program. The collected rainwater will be used for outdoor irrigation, and the water savings achieved will be above and beyond the planned water savings.

To encourage residents to conserve, water use will be billed using a tiered rate structure so that the cost of water increases as residents exceed their water budgets. Dual meters that measure both indoor and outdoor water will allow residents to track their water use and adjust it accordingly. Water wasters will be given warnings and required to pay extra, after which their service may be temporarily cut off.

In addition, Sterling Ranch “Water District” will have a dedicated water conservation staff to develop water conservation specifications as well as programs to educate the school children and community residents about the importance of water conservation.

In the past, Douglas County communities largely depended on non-renewable groundwater, but Sterling Ranch will use a combination of surface water, drawn mostly from the South Platte River, and groundwater mainly to manage drought or supplement the water supply. The community will also share its water with 700 neighbors whose wells are running dry.

Alamo Creek. Photo credit: NUVIS Landscape Architecture and Planning

Another exemplary water-saving residential development is Alamo Creek in Danville, California near San Francisco. This 600-acre planned community will include 927 residences, artificial turf soccer fields, a school, fire station, and parks. The homes will include single-family residences that cost between $600,000 and $1,000,000, townhouses, and affordable senior apartments. Alamo Creek, which opened in 2006, is expected to be completed by 2016.

During the planning stages, the Environmental Impact Report determined that Alamo Creek would need .7 million gallons of water per day (later lowered to .45 mgd after onsite conservation and recycled water were figured in), but half of the community lies outside the boundaries of the local water service provider, East Bay Municipal Utility District (EBMUD). In order to secure water for the project, Alamo Creek’s developer, Shapell Homes, had to agree to a zero net impact on EBMUD’s water resources, and even promise to save 2 gallons for every 1 gallon used by residents.

Water efficient landscaping. Photo credit: NUVIS Landscape Architecture and Planning

Onsite, the residences are equipped with dual flush toilets, efficient appliances, and include drought tolerant landscaping designed for water conservation. Since residents usually use more water outdoors than indoors, Nuvis Landscape Architecture and Planning spent two years designing the landscaping, and worked hard to find native water efficient plants with color and texture. Common areas will also have water-saving landscaping, with smart irrigation controllers that adjust the amount of water released according to weather conditions. Recycled water will be used for large expanses of turf.

While the typical daily water budget in EBMUD’s district is 500 gallons, Alamo Creek’s average is 320 gallons a day. Each residence has a monitored water budget and is charged extra for exceeding it. Homeowners are given a book about water saving plants and landscaping, and an onsite educational exhibit provides information about water conservation.

To save 2 gallons of water for every 1 used, Alamo Creek had to go beyond onsite conservation and help EBMUD reduce water use offsite in the rest of its service area.  For each new home, Shapell Homes pays EBMUD several thousand dollars, which EBMUD invests in conservation measures for its customers outside of Alamo Creek. These measures include (they are subject to change if new technology provides better options) providing individual resident water meters in multifamily residences, replacing toilet flapper valves, reusing water for industrial and commercial uses, using indoor wastewater for irrigation, and making smart irrigation controllers available.

Alamo Creek’s innovative partnership with EBMUD is a model for developers and water utilities in water stressed areas, and as a result, the community has won a number of awards including the Sustainable Visionary Project of the Year in 2007.

The WaterSense program of the U.S. Environmental Protection Agency (EPA), which promotes water efficient products and practices, launched its New Homes Pilot Program in 2008. In order to be labeled a WaterSense home, a residence must use WaterSense plumbing fixtures, efficient hot water delivery systems, and water conserving landscaping. If included, appliances must be Energy Star models, and irrigation systems must be designed or installed and audited by WaterSense irrigation partners. The EPA estimates that a WaterSense home can save residents 10,000 gallons a year, in addition to cutting energy use from needing to heat less water.

The first neighborhood of WaterSense homes was built in Briar Chapel, a green community development near Chapel Hill, NC. Other WaterSense homes are being constructed in Hendersonville, N.C., Colorado, Massachusetts, Arizona, California, Texas and Wisconsin. Pulte Homes is now building 20 new WaterSense homes in severely water stressed Las Vegas. These homes will all feature WaterSense toilets, showerheads, faucets, water efficient washers, and water-saving landscaping and smart irrigation controllers.  But in order to collect a broader range of data, some will be fitted with additional water conservation equipment such as water pressure reduction valves, submeters to monitor indoor use, or leak detectors.

LEED (Leadership in Energy and Environmental Design), the green building certification system developed by the U.S. Green Building Council, has developed LEED for Neighborhood Development. While LEED-ND places no maximum or minimum size limit on green neighborhood projects, it considers a reasonable maximum size to be about  320 acresLEED-ND awards points and certification for achievement in: Smart Location and Linkage, Neighborhood Pattern and Design, Green Infrastructure and Buildings, Innovation and Design Process, and Regional Priority Credit, with criteria for building and landscape water efficiency, and wetland and water body conservation included within these categories.

Because of the economic turndown, homebuyers are increasingly choosing smaller homes that are cheaper and easier to maintain. And although the housing market remains weak, the green building market is estimated at $36 billion to $49 billion, and expected to double by 2013. A new survey conducted by the National Association of Home Builders found that green features, particularly water efficiency, is high on the list of desired attributes in new homes for 2015. With time running out to preserve our scarce water resources, building water efficiency and conservation into new homes and communities is the approach all smart and forward-looking developers should now be taking.

Columbia Water Center demonstrates research-based solutions to global freshwater scarcity and climate-related water risks.  Follow Columbia Water Center on Facebook and Twitter

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Advanced Irrigation
12 years ago

Excellent reading. For what it’s worth, we’re doing our part to use irrigation systems that keep conservation in mind. When newer, improved products become available in the future, we’ll undoubtedly move toward those.

Jarl Kubat
11 years ago

Living in Arizona I understand the value of water. I hope as new communities are designed and built they will continue to incorporate and expand on the water conservations ideas from the communities listed in your article.