Mechanics of Water Conservation

By Gunnar I. Baldwin, Toto USA, Inc., New York October 1, 2006

Water today has become a hot topic among those trying to reduce their impact on our precious environment. And as water and sewer rates climb rapidly, water consumption has also become an important subject when considering how to reduce costs and impact to the bottom line. Most commercial buildings are typically large consumers of water, and frankly, the largest percentage of their indoor water use passes through their toilets. As a result, most facilities managers are receptive to solutions for increasing the water efficiency of their buildings.

At the same time, many building operators have had bad experiences with early versions of the 1.6-gpf toilets that claimed to help reduce water consumption. The change in plumbing code requirements subsequent to the Environmental Policy Act of 1992—which required that all new toilets manufactured for U.S. installation flush no more than 1.6 gallons—forced manufacturers to make drastic changes to the designs of these products. For several years after, there were only a few models whose performance could be considered satisfactory. So there has been a natural reticence on the part of facilities engineers to make the big step to changing out all of their toilets in order to positively affect water conservation.

Uniform North American Requirements for Toilets

But this is changing. The most influential factor has been a movement started by the water utilities to reduce the demand on their infrastructure. Consumption of potable water in many cities has grown dangerously close to capacity, compounded by droughts. However, a less talked about concern is the ability to properly treat the wastewater produced by this consumption; it is much easier to talk about water supply problems in polite company than sewage problems. Nonetheless, the latter is a more compelling reason to reduce the amount of water that runs through our buildings. Because utilities are interested in finding ways to reduce consumption—and they have successfully encouraged the retrofit of existing buildings by investing in rebates for more efficient fixtures—the performance of these fixtures, especially toilets, has been scrutinized. Now, a new consumer-driven, supplementary performance standard—Uniform North American Requirements for Toilets—is being developed thanks to the research funded by these utilities. As a result, it is now possible to refer to third-party tests to identify the products that perform well. In the past, manufacturers in the industry wrote the national standards in both the U.S. and Canada, and these standards did not require toilets to perform to the utilities’ or consumers’ expectations.

Maximum Performance Tests (MaP Tests)

Under the third-party tests, toilets are now tested to see how much waste they will flush away, instead of for their ability to clear the bowl of a minimal amount of media. Additionally, the MaP test media being used is far more realistic and, therefore, more discerning about real performance than the media used in the various tests included in the American ANSI 112.19.2 and Canadian B-45 standards for vitreous china toilets. This MaP testing is new to the industry, but it has already caused most manufacturers to go back to the drawing boards and design their products to score well. Unfortunately, until there is a greater variety of MaP test media, such as floating waste and dissolved waste, the results with current sinking waste media alone do not give the whole story. But what it does provide certainly goes a long way to fill the end users’ knowledge gap about performance. MaP tests also give the facilities engineer greater confidence in making the right choice when selecting replacement toilets, which after all are “the most important seats in the house.”

EPA’s WaterSense Program

MaP test scores will be an important credential in earning the right for a toilet to bear a new label called “WaterSense” in a program to be launched early next year by the EPA. The EPA has developed this program with the help of a large number of stakeholders, including utilities as well as manufacturers and environmentalists. The label will help a specifier or end user identify water-efficient products based on third-party, independent testing rather than relying solely on the marketing claims of manufacturers. Announced in June by EPA Director Stephen Johnson, the new WaterSense program is expected to launch in early 2007. It promises to be of great assistance by giving end users and specifiers more valid criteria on which to base their selections of plumbing fixtures and fittings as well as other water-using equipment.


Coincident with the improvement in information related to the selection of water-efficient products is the influence of the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) rating system, which is encouraging building owners and facilities managers to make their buildings green. The USGBC offers up to five LEED water-efficiency credits: two for reducing potable water use for irrigation; one for reducing potable water use for sewage conveyance; and two for reducing potable water use inside a building, which water-efficient toilets can help realize. Many cities are now at least encouraging LEED certification, and some are outright requiring it, as does the General Services Administration, arguably the nation’s largest landlord. The rising awareness of the need for sustainable buildings is catching on in epidemic proportions.

Armed with the tools needed to recognize the toilets that perform well, there are now many examples of buildings and institutions that have successfully changed out all of their toilets and found the lower consumption models to be much less troublesome and maintenance-prone than the older wasteful models. They have also found that reduced water use has energy-savings benefits as well. Imbedded in the flow of water through a building’s pipes is the energy used to pump it there at the pressures needed to operate the fixtures in the building. In fact, the state of California has estimated that 4% of its power is used to pump water. Savings measured in water consumption, energy consumption and dollars are real and significant. Return on the investment is rapid and can indeed be paid for by the savings.

The University of Mary Washington

Russ Horner, of Water Management, Inc. (WMI), an Alexandria, Va.-based performance contractor specializing in water efficiency, provides the following example of the benefits gained by the replacement of water-guzzling toilets with water-efficient models:

In December of 2001, the Commonwealth adopted the Virginia Energy Plan with the goal of operating the state government as a model of energy efficiency. By 2002, plans were being formulated to make greater use of the private sector through the use of performance contracting.

The University of Mary Washington, located in Fredericksburg, Va., was strongly encouraged by the Commonwealth to look into performance contracting. The university engineering staff was skeptical about any effort to introduce low-flush toilets, because a review of their maintenance logs indicated that the majority of their maintenance time was devoted to unclogging toilets, and they felt that this would only be exacerbated with the introduction of toilets that used less water for flushing.

Prior to the start of the water portion of the project, WMI conducted a detailed water-efficiency audit of the 38 buildings that comprise the main campus. The audit showed that a majority of sanitary fixtures were old and obsolete. Most of the water to these buildings ran through only two water meters. Water analysis showed that the campus was using more than 46 million gallons of water every year. WMI replaced toilets, urinals, sinks, faucets, aerators and showerheads. Installing new high-efficiency sanitary fixtures, which use less than 50% of the water needed to achieve the same flushing and rinsing effect as the outdated fixtures, realized significant savings for the university. None of these changes required an adjustment in operation or in the way people perceived or used the devices.

In implementing various conservation measures at Mary Washington, WMI estimated it would save over 18,983,000 gallons of water a year—more than 45% of the total water usage of the campus! Actual savings have exceeded this amount. Between the cost of the water and the energy needed to heat it, the savings to the university is over $112,000 a year.

WMI was so certain of the savings that it guaranteed them in writing. In fact, all of WMI’s “performance contracts” are structured to guarantee reductions in water, sewer, energy and operational costs over time.

This successful project provided the university with guaranteed energy and monetary savings and also upgraded the comfort and appearance of aging facilities that faculty, staff and students all call home. By replacing antiquated toilets, faucets and showerheads with new high-efficiency fixtures in campus dorm bathrooms and public restrooms, WMI dramatically reduced water usage while, in most cases, actually improving both the quality of water delivery and aesthetics of the facility. These new devices will require less maintenance and upkeep than their less efficient predecessors.

Another example of a successful retrofit comes from a 504-bed hospital in Toronto that changed out 128 toilets in 2003 and saved 16% of its total water consumption. According to Bill Grant, director of facilities management, it’s been a win-win experience with replacing old toilets with ultra-low-flush models. “The water savings from the six-liter toilets has exceeded our expectations. More importantly, patients are happy because the toilets flush clean on their first try,” said Grant.

Realized Expectations

Facilities managers’ changing from waterguzzling to water-efficient toilets has joined the ranks of the best management practices. Will this change the fact that the U.S has the largest water use per capita in the world? Probably not right away. But with the encouragement of water utility rebate programs and other incentives, rising water and sewer rates, the new standards discussed above that help us identify the products that perform well and educational programs such as the U.S. EPA’s’ new WaterSense label, we may be headed in that direction. The underlying truth is that unless these new toilets’ performance is acceptable to their end users in every way, we will not see their adoption. Therefore, it is critical that we design our standards to protect our consumers’ interests and that manufacturers design products that minimize water use at the same time satisfying the needs of the people that use them.

USGBC’s Leadership in Energy and Environmental Design (LEED) Rating System:

The LEED rating system is the nationally accepted benchmark for the design, construction and operation of high-performance green buildings.

The LEED rating system addresses nearly every aspect of a building’s design and construction:

* Site selection

* Fuel consumption to transport materials to the jobsite

* Heating system energy efficiency

* “Friendliness” of interior to occupants

* Amount of “light pollution” affecting neighbors

* Amount of potable water consumed by plumbing fixtures

During the past few years the acronym has become almost as ubiquitous as the color green itself.

And LEED is not just about new buildings; the USGBC has a LEED for Existing Buildings (LEED-EB) rating system that applies to those buildings already built before we became as conscientious about the sustainability of our existence.

LEED can be applied to every building type and phase of a building life cycle, including:

* New commercial construction and major renovation projects

* Existing building operations and maintenance

* Commercial interiors projects

* Core and shell development projects

* Homes

* Neighborhood development

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