Owners and operators are now coming to the realization that water conservation and other "Green Building"

Water-free urinals provide an alternative to reduce water consumption—100% water savings—in new construction and retrofit projects. (Photo courtesy of Sloan Valve Co.)

Why Conservation?

With the overall demand for water increasing-public usage in 2000 was 43 billion gallons a day, compared to 14 billion gallons a day in 1950, according to the U.S. Geological Survey (http://water.usgs.gov/watuse/)-the price of water will continue to climb. While recent rains have improved the situation, the constantly growing demand on the nation's water supply continues to raise U.S. water costs, and with no way of knowing when the next drought may happen, cost relief does not appear to be imminent.

Another driver is that the demand for water is not only greater than ever, but spread thinner by population growth in areas once considered uninhabitable. Booming expansion in the Western United States became possible with the diversion of water from the Great Lakes and Colorado River feeding the initial demand. However, by building large dams, diverting river water and levying rivers, the condition of our nation's aquatic systems is being degraded, and we are destroying the very systems upon which we are dependent.

After decades of abuse, the ecological toll on these systems became evident, prompting the Water Resource Development Act (WRDA), which gave the Great Lakes region's governors direct authority over the water. Amended in 2000, the U.S. Congress maintains that four of the Great Lakes are international waters and are defined as boundary waters in the Boundary Water Treaty of 1909 between the United States and Canada. As such, any new diversion of Great Lakes water in the United States would affect the relations of the government of the United States with the government of Canada.

The WRDA further states that no bulk export or diversions of Great Lakes waters out of the Great Lake basin can take place without the unanimous approval of the Great Lakes governors. Because these states thrive economically on their natural resources for both industrial use and hospitality draws, flow of water to other regions is becoming much more costly.

The changing landscape of the building industry requires plumbing engineers to become knowledgeable about conservation so investors can benefit from lower operational costs. The same is true for engineering firms that must be able to assemble and maintain records necessary to document a building's compliance with LEED requirements and define new construction methods per LEED guidelines at a reasonable cost.

LEED Engineer

LEED credits are earned based on performance rather than prescription, with the total number of points earned determining a building's status: LEED Certified (26-32 points), Silver (33-38 points), Gold (39-51 points) or Platinum (52-69 points).

One of the simplest ways to earn LEED credits is by surpassing the standards for Water Efficiency. That means reducing water consumption 20% below the baseline fixture performance requirements set by the Energy Policy Act of 1992 for one point, or reducing consumption by 30% in comparison with the baseline for two points. With a reduction of 40% beyond the baseline standards, engineers can also earn an additional point from the Innovation and Design Process category. And because 41% of water use in an office building is consumed by water closets, urinals and faucets, according to the DOE, this LEED category can contribute tremendously to the bottom line, making the specification of efficient fixtures very cost effective over the life cycle of the facility.

For example, a baseline toilet fixture uses 1.6 gallons per flush (gpf) (6 liters) and a baseline urinal consumes 1.0 gpf (3.8 liters). Consider then the bottom line impact of a design strategy that uses 0.5 gpf (1.9 liters) urinals or even water-free urinals and ultra low-flush toilet fixtures (1.0 gpf/3.8 liters). Another key source of water savings is sensor-operated lavatory faucets with 0.5 gallon per minute aerators. These green products reduce consumption because water flows only when a person's hands are in the "active area,"

A standard urinal consumes 1.0 gpf (3.8 liters), but consider the impact on overall consumption with installation of a 0.5 gpf (1.9 liters) model. (Photo courtesy of Sloan Valve Co.)

Project Planning

Measures taken to achieve Water Efficiency objectives can overlap into other LEED categories. Having a command of green products and understanding the intent of the LEED criteria can help maximize point-earning potential. For example, low-flow urinals contribute to achieving water efficiency goals. Additionally, the same product may be manufactured from recycled content, as well as being regionally manufactured (within a 500-mile radius of the project site)-both of which can contribute to achieving multiple Materials and Resources points.

To attain the highest possible LEED rating, all water-consuming fixtures should be selected for their ability to meet the intent and requirements of the LEED credits. They should, of course, conserve water, provide durability for long-lasting service and maintain the standard of performance to which people are accustomed. This is an important point for engineers because poor-performing technologies will result in waste, i.e., double flushing, which negates conservation, and may well cause additional costs in operations and maintenance due to clogged toilets and overflowing bowls.

In essence, to earn true acceptance, green products simply must use less water to do the same job without anyone noticing.

Retrofits

LEED for Existing Buildings (LEED-EB) provides engineers the opportunity to market their services to owners and operators of all existing buildings by explaining the financial and environmental benefits of sustainable facilities. LEED-EB covers a significant market, with more than 4.6 million buildings in the United States already standing and billions of square feet of existing space that would benefit from the green design approach.

For these existing buildings, one of the first elements to examine to earn LEED points is the restroom-specifically, flushing technologies. The advantage of retrofitting old flushometers is that products have vastly improved in terms of water efficiency over the past decades.

Flushometer technology for virtually every type of building is the industry standard due to its ability to precisely meter water and recycle quickly for consecutive users. However, plumbing engineers must be careful in their specifications, as some flush valves allow external adjustment of the amount of water used to flush the fixture, which can negate conservation efforts.

A new technology that provides immediate and drastic water savings is water-free urinals that connect directly to existing drainlines for simple retrofit applications. Water-free urinals have been developed to maximize conservation efforts without sacrificing hygiene, using a liquid-sealed cartridge to form a barrier between the open air and urine, which prevents any odors from escaping from the drainline. While codes and standards still limit their use in some areas, this technology is gaining strong support. Other retrofit options include upgrades of manual faucet units into touchless models that can have a large impact on water consumption.

Of course, there are additional design elements that affect water conservation in relation to LEED and operation and maintenance (O&M) costs, but starting in the restroom with the most conspicuous water-wasting culprits makes the most sense for existing space.