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Water Conservation and Plumbing Technology with Marty Laporte

Associate Director of Utilities for Water Resources and Environmental Quality, Stanford University Utilities Division, Stanford, Calif.

Marty Laporte is the Associate Director of Utilities for Water Resources and Environmental Quality, Stanford University Utilities Division.

How has water conservation changed as a priority in recent years? Why?
Stanford University is fortunate to have multiple water sources: non-potable lake water, groundwater wells, and very high quality domestic water from San Francisco Public Utilities commission (SFPUC). For more than 100 years, Stanford has been using non-potable lake water to irrigate campus grounds.
In 2000, Stanford identified 14 water conservation measures in its Water Conservation Master Plan that would enable it to reduce water use and comply with the General Use Permit condition that requires Stanford does not exceed its allocation from SFPUC while developing some 2,000,000 square feet of academic facilities. Since 2001, Stanford has developed and implemented an aggressive water-conservation program.
The first steps in the program were: to identify existing conditions, establish the water-conservation measures, and formulate a budget to implement the program. Since 2001, water-use efficiency and conservation have increasingly become an integral element for planning new buildings and major renovations. In the last two years, we developed water-efficiency goals that increase water efficiency above and beyond current standards, such as the plumbing code. The water-efficiency goals are updated as new information about relevant technologies becomes available.

In 2006, Stanford installed low-flow plumbing fixtures to help curtail water use. Did these retrofits achieve their desired results?
Not all our retrofits have materialized the water savings we estimated. Some water-conservation measures have been less effective, such as dual-flush toilets and irrigation water audits, while others, like water misers, have saved more water than we expected. Since 2001, when Stanford started implementing its water-conservation program, we have installed more than 10,000 water-efficient bathroom fixtures, including high-efficiency urinals and high-efficiency toilets. We also have retrofitted our sterilizers with water misers and installed other water-efficient equipment in our research buildings.
Although we meter indoor water use separately in most of our academic and student housing buildings, it is not always straightforward to attribute water savings to a specific bathroom retrofit. One of the key reasons for this is that there are many variables that impact water use, even in buildings that don’t have wet labs. For example, building activities and occupancy may vary, so savings from selected retrofits may be overshadowed by higher water use because more people are using the building. We do know that the various measures implemented by the water-conservation program have reduced Stanford’s water use by 17 percent since 2001.

What unexpected problems did you run into during installation, after? Solutions?
We have encountered a number of unexpected problems. In a sense, Stanford’s water-conservation program is like a startup, and we’ve had to learn on the run to avoid missing opportunities during large-scale building retrofits or new construction projects. The key lessons we’ve learned are: there is huge variability in the design and quality of water-efficient products – we can’t assume that just because some products have been on the market for several years, all these water-efficient products will save water; the need for testing products on a small scale can provide very useful data before embarking on large-scale installations; to materialize long-term water savings, communication with users is critical, before, during, and after installation of water-efficient products; close partnerships with experienced plumbers, reliable and responsive vendors, and building managers have a big impact on success of water-efficient installations and resulting water savings.
Our main solution to solve the conundrum about what new technology will work for us and actually save water was to start a new water-efficiency technology demonstration program. We contact various vendors and asked if they are willing to provide samples for us to try out to determine if their technology meets our needs. Once we install the samples, we track user comments, such as number of double flushes when using high-efficiency toilets, and, of course, evaluate whether the equipment is likely to save water.

During the retrofits, what did you learn during testing that affected what or how you specified the plumbing products?
I learned that design and ease of use matter a great deal. I also learned that vendor support and willingness to work with clients for the long run is critical. We received good quality products from many vendors, but very few would respond to questions, suggestions or requests for information about their product. So, of course, the winning products, the ones I recommend, are those that are well-designed – simple to use, easy and inexpensive maintenance – will save water, and have good technical support.

How has occupant behavior affected the implementation of water-saving plumbing technology? Please provide examples.
The best water-saving technologies are not noticed – as a reduction in performance – by the user. For example, the users of autoclaves don’t even notice the water misers we installed on dozens of autoclaves on campus and that they save hundreds of thousands of gallons per year. Other water-saving technologies are more personal, like showers. This is why testing the bathroom fixture water-efficient technologies is so important. When we tested the pint urinals and asked users to comment on their performance, the overwhelming number of comments were positive, even from our plumbers. That was a vote of confidence.
On the other hand, certain dual-flush toilets require instructions for low-flush use, which is silly and can significantly impact water savings. Also, low-flow showers bring out comments from users, as you know. Most of us expect an almost spa experience in our showers, so reducing flow requires a lot of testing, communication and feedback from users. The technology is still developing, so 1 gpm showers are not the same experience at this time when compared with a 2.5 gpm shower – current plumbing code.
However, manufacturers are improving their technology and some are working with us to help us develop a menu of reliable, water-efficient products that we can use in our buildings and landscaping. We will continue to work with manufacturers who are innovative and produce products that are well designed, save water and that customers like. It’s great to be surfing the water-efficiency wave.

What are the most common types of plumbing products specified by the university to improve water conservation? What are the common maintenance and repair activities for these products?
Of course bathroom- and kitchen-water using fixtures are high on our water-efficiency plumbing list. Certainly the research buildings also have water-using equipment that needs to be efficient. Water-efficient technology is booming for fixtures and equipment, so everything in the water-efficiency industry is changing fast. The challenge is to somehow keep track of the technology and what works and saves water.

What technologies are you exploring next related to water conservation?
I’m trying out water-efficient faucets and toilets that use sensors that are powered by the water running through them rather than batteries that need to be changed and disposed of and recycled. I’m also looking into water-efficient reverse osmosis (RO) systems and simple designs that could be incorporated into a research building to reuse the RO reject water for non-potable purposes, such as trap priming or quenching hot wastewater from sterilizers. In addition, I am compiling references for water-efficient equipment for research labs.

posted:  3/5/2008