By Michael Arny and Betsy Braun, Leonardo Academy
Driving down water use is a way to advance sustainability as well as earn more points toward achieving LEED© certification, the U.S. Green Building Council Green Building Rating System. To get an update on what is happening today in the marketplace, we interviewed Rob Zimmerman, Senior Staff Engineer, Water Conservation Initiatives, of Kohler Co., and Stephanie Thornton, Marketing Outreach Specialist of the U.S. Environmental Protection Agency (EPA).
Interview with Rob Zimmerman, Kohler Co.
Leonardo Academy Question: How are dual flush toilets working in the market place?
Rob Zimmerman Answer: They work fine. One of the many things we talk about at Kohler is how different products work in different applications. Dual flush toilets work well in residential applications because the residents are typically motivated to save water and know how to use them properly. They don’t work as well in commercial applications because there are many different people using them. The users may not be familiar with how they work or care about saving water. In commercial applications, we feel a single flush toilet with 1.28 or 1 gallon per flush (gpf) provides more predictable water savings.
Leonardo Academy Question: What kind of flush rates do dual flush toilets typically have?
Rob Zimmerman Answer: Flush rates vary. For most Kohler and Sterling brand dual flush toilets, a full flush is 1.6 gallons; a short flush is 0.8 gallons.
Leonardo Academy Question: What is the lowest water usage flush toilet available and how much water does it require to flush?
Rob Zimmerman Answer: The lowest single flush toilets that Kohler makes are our Pressure Lite models, which use only 4 liters or 1 gallon per flush.
Leonardo Academy Question: What is the lowest water use flush urinal available?
Rob Zimmerman Answer: The lowest water use for a flushing urinal is 1/8th gallon (one pint) per flush. The highest water use for a flushing urinal certified to carry EPA’s WaterSense label uses no more than a half gallon per flush.
Leonardo Academy Question: What interest are you seeing in non-water urinals?
Rob Zimmerman Answer: Non-water urinals are best in situations where there is both high usage and reliable maintenance such as in stadiums and airports. The cost associated with maintenance needs to be considered, but with Kohler’s Steward non-water urinals, that cost is more than offset by water savings. In cases where the non-water urinals aren’t allowed by plumbing codes, the 1/8 gallon is the best choice. For retrofits of old buildings, , the ½ gallon urinals may be better. Knowing your building and how the fixtures will be used are part of specifying a product. These are examples of elements other than water efficiency that must be considered when choosing the right product for the application.
Leonardo Academy Question: What kind of interest is there in low-flow residential bathroom faucets?
Rob Zimmerman Answer: To qualify for EPA’s WaterSense label, ‘private use’ bathroom faucets, such as homes, hotel rooms, and hospital rooms, should be 1.5 gpm or less. Since early2009, all Kohler private-use bathroom faucets comply with this standard, which has taken over the market. Previously, bathroom faucets had a flowrate of 2.2 gpm. People don’t really notice the difference, as they use these faucets for brushing teeth, washing hands, etc.
Commercial faucets are limited to 0.5 gpm, and there is no movement to go lower. You need some minimum amount of water to wash your hands, and so there’s a diminishing return in reducing water flow rates at some point.
Leonardo Academy Question: What kind of interest is there in low-flow kitchen faucets?
Rob Zimmerman Answer: Kitchen faucets are different from bathroom faucets because volume is more important than flow rate. For example, the same amount of water is needed to fill a pot, so reducing the flow just causes inconvenience doesn’t save water. The standard for kitchen faucets is 2.2 gpm.
Leonardo Academy Question: What kind of interest is there in low-flow showerheads?
Rob Zimmerman Answer: A lot of research is currently being conducted with showerheads. There are more aspects to showering than just washing, such as being able to rinse shampoo out of hair and showering for relaxation. The question is how do you design a showerhead that addresses these issues and at the same time saves water and energy? When this research is completed, the EPA will most likely adopt it as a performance standard in the WaterSense program. Currently the standard flow rate for showerheads is 2.5 gallons per minute.
The EPA WaterSense program is playing an important role in plumbing fixtures the same way that Energy Star is to other products, such as washing machines and dishwashers. People have a long memory when it comes to the performance of plumbing products! Educating consumers to become more aware of this program helps them identify products that save water without sacrificing performance.
Interview with Stephanie Thornton, Marketing and Outreach Specialist for the U.S. Environmental Protection Agency’s (EPA’s) WaterSense program
Leonardo Academy Question: Could you tell us about the purpose and history of the US EPA WaterSense Program?
Stephanie Thornton Answer: The WaterSense Program is a U.S. Environmental Protection Agency (EPA) sponsored partnership program launched in 2006. The WaterSense Program promotes water efficiency and enhances the market for water-efficient products, programs, and practices. The WaterSense label for products helps consumers identify water-efficient products and programs that meet WaterSense water efficiency and performance criteria. WaterSense brings together local water utilities and governments, product manufacturers, retailers, consumers, and other stakeholders to:
- Decrease indoor and outdoor non-agricultural water use through the adoption of more efficient products and practices.
- Help consumers make water-efficient choices, including differentiating between products and services in the marketplace and adopting simple daily activities that reduce water use.
- Encourage innovation in manufacturing
- Establish and standardize rigorous certification criteria that ensure product efficiency, performance, and quality
Leonardo Academy Question: Is the US EPA WaterSense Program focused on residential or commercial fixtures?
Stephanie Thornton Answer: Initially the WaterSense Program focused on residential products and services, but currently the program is expanding its focus to include the commercial sector.
For example the WaterSense Program recently released its specifications for commercial urinals which require that water use not exceed 0.5 gpf. This is important because according to WaterSense research, nearly 65 percent of the urinals in use today—approximately 7.8 million fixtures—exceed the maximum allowable flush volume set by federal standards of 1.0 gpf.
