Water Conservation Strategies Can Improve Your Bottom Line

10/27/2005


Water conservation and green building strategies are more than just environmentally responsible decisions. They make economic sense as well.credits in the water efficiency category.

Increased Demands for Water

According to the 2000 U.S. Geological Survey, more than 268 million people depend on water from public suppliers and use an estimated 43 million gallons a day. As the population continues to grow, and parts of the country are affected by droughts or natural disasters, strains on our natural water supply systems become apparent. Conservation of water resources in green buildings involves strategies to use less water for plumbing fixtures, HVAC equipment, appliances and irrigation.

To be effective, water conservation, as well as water heating energy conservation should be considered early in design, monitored during construction and properly commissioned to ensure their proper installation and operation.

Take the LEED

The Leadership in Energy & Environmental Design (LEED) rating system was created by the U.S. Green Building Council in 1995 to promote building strategies that achieve maximum energy efficiency and environmental sustainability. In addition to the obvious accomplishment of green building, which are beneficial to the public and the overall environment, the LEED rating system may also provide an ancillary business benefit. First, such green buildings are more profitable over time and have reduced operating costs; and second, there is a growing array of state and local government incentives for LEED certified projects.

LEED credits are earned in the water conservation category if the following requirements are met:

%%POINT%%Building employs high-efficiency irrigation or uses captured rain or recycled site water to reduce potable water use for irrigation by 50%.

%%POINT%%Building reduces the use of municipally provided potable water for building sewage conveyance by a minimum of 50%.

%%POINT%%Building meets the 20% reduction in water use requirement for the entire building and has an ongoing plan to require future occupants to comply>

Once a plan has been established for earning LEED credits, the most effective place to start is with facility restrooms.

Focus on the Restroom

Restroom fixtures consume one-third of the fresh water delivered to a facility, which in turn becomes one-third of the sewage output. Reducing demand for water is the most effective and economical strategy to earn LEED credits and can have a significant and instant impact in the reduction of water usage.

Many of today’s water-conserving plumbing fixtures, fittings and appliances have been improved to work better than product from the past while limiting maintenance problems.

Sensor-operated lavatory faucets consume less water, because they are activated only when the users’ hands are in the “sensored” zone. Water turns on and off automatically, minimizing waste. These new faucets use aerators to simulate the feel of stronger water pressure, while only producing 0.5 gallons of water flow per minute. Compared to the typical handle faucet that consumes 2.2 gallons per minute, the reduced usage is noteworthy.

Low-flow, self flushing toilets and urinalshave been developed that use just 1.0 gallon per flush. This is significantly less than the Environmental Protection Act (EPACT) of 1991 which mandates 2.5 gallons (from five gallons per flush).

Water-free urinals use new technology to maximize water conservation without sacrificing hygiene. A liquid-sealed cartridge forms a barrier between the open air and urine, preventing odor from escaping the drain line. These urinals connect directly to existing drain lines and can provide an immediate return on investment in terms of water saved from eliminating flushing or continuous water circulation.

Credits for Savings

By incorporating these water-saving fixtures into a typical 100,000-square-foot office building, engineers can achieve savings of thousands of gallons of water per year. Plus, these fixtures surpass the establish standard for Water Efficiency and earn LEED credits.

Credits are awarded based on the percentage of reduction in consumption. For example, one point can be earned for reducing water consumption by 20% below the baseline requirements set by the Energy Policy Act of 1992, or two points for reducing consumption by 30%. Taking this a step further and incorporating additional conservation strategies into your building can increase the LEED credit points earned. A reduction of 40% beyond the baseline standards earns an additional point in the LEED Innovation and Design Process category.

With more than 40% of water in an office building consumed by toilets, urinals and faucets, this LEED category can contribute tremendously to the bottom line, making the specification of efficient fixtures cost-effective over the life cycle of the facility.

Graywater Systems

After installing water-conserving plumbing fixtures in all the restrooms, consider incorporating a graywater system to provide irrigation and get a second use out of the water drained from bathroom sinks and other fixtures. This is an effective way to reduce the use of treated potable water.

It is important to consider graywater collection and irrigation systems early in the design process, as they will affect landscaping design and the size and placement of mechanical spaces. This is especially true for gravity-flow graywater systems, since they must be higher than the irrigation systems they service.

Water-Heating Energy Conservation

Reducing the amount of hot water used also reduces the energy required to heat that water. Water heating energy can be further conserved with little extra cost by insulating piping, recovering waste heat from graywater with recirculation pumps, and by specifying highly efficient boilers and hot water heaters. Many advances have been made in water heating technology in recent years, including sealed combustion chambers, electronic ignitions and direct-vent condensing boilers. Capital costs for efficient heaters can be greatly reduced by taking advantage of the Federal Environmental Protection Agency Energy Star program.

For example, solar water heating can eliminate the need to use non-renewable energy. Low-temperature, unglazed solar water heaters are one of the most inexpensive and well-proven renewable energy technologies. Glazed flat-plate collectors can provide the higher temperatures required by service water, and can be very attractive when integrated with the envelope design. Low-interest loans and tax rebates provided by the federal government for solar equipment can help to reduce capital costs of solar systems.

Designs incorporating efficient conventional and solar water heaters or graywater systems should be followed up with testing and commissioning before occupancy, to ensure they operate as intended, and that building operators are well trained in their use and maintenance. Lack of proper testing, commissioning and training is one of the most common reasons for unsatisfactory performance. However, if systems are installed and operating correctly from the beginning, they typically provide years of service, saving water, energy and money.

Landscape Irrigation

Another way that industrial and commercial facilities can reduce water use is through the implementation of efficient landscape irrigation practices. Consider a landscape design that incorporates indigenous plants, wildflowers or wetlands for a low maintenance plan that uses less water as well.There are also drip systems and deep-root systems %%MDASSML%% water-efficient irrigation equipment - that distributes water evenly just in areas that it’s needed further eliminating water waste.

Education

One of the most important steps in conserving water can also be one of the easiest and least expensive—education. By demonstrating to management and employees the amount and cost of water used and wasted, they’ll have a better understanding of the true costs involved and the role they can play in conservation.

Start by examining how much water is used daily to gather baseline information.This “true” reading of water use can be used to set company goals on acceptable limits and be used to develop specific water use efficiency measures. Plus, it will raise awareness of water use rates while making it easier to measure the results of conservation efforts. Consider using meters on individual pieces of water-using equipment for instant readings on the efficiency of water use. Records from these meters should then be used to identify changes in water use rates and possible problems in a system, for a complete and consistent picture.

Incorporating water conservation strategies into your existing building strategy or new construction project makes sense over the long term.Reduction in water usage will contribute to your bottom line and have a positive impact on the environment, as well.





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