Water Efficiency-Composting Toilets

Case Study
Company- Clivus Multrum- Foam Flush Toilet

The Bunker Interpretive Center at Calvin College, used a composting system The Center also connected its gray water to indoor planting with a conventional septic system for back up. These types of toilets have been specified at Battery Park City, Chesapeake Bay Foundation, University of British Columbia and the C.K.Choi Center; which is a 30,000 sq ft building.

Two basic design requirements would be that a proper ventilation system is provided and composting tanks will need to be located directly under the toilet fixtures. The owner’s manual will need to provide instructions for maintenance.

Linkow, Alex, “Compost Happens”, July/August 2005
<http://www.clivusmultrum.com/new_article_0507_recreation_management.pdf.>(19 June 2007).

Clivus, “Case Study: Bunker Interpretive Center Calvin College, Grand Rapids, Michigan”, 
<http://www.clivusmultrum.com/new_article_0501_eco-structure.pdf > (19 June 2007).

Linkow, Alex, “Compost Happens”, July/August 2005
<http://www.clivusmultrum.com/new_article_0507_recreation_management.pdf.> ((19 June 2007).

Linkow, Alex, “Mule Creek Junction: A Tale of Toilet Technology”, May 2004
<http://www.clivusmultrum.com/new_article_0505_pm_engineer.pdf>  (19 June 2007).

Water Efficiency-Lavatories

Case Study
Company- Bradley Corp

According to Jon Dommisse, Director of Marketing and product development for Bradley Corp, the sensor performance associated with touch free fixtures is the greatest problem.  He claims that the managers did not trust the technology, ‘They shorted out, and there were a lot of problems with sensor-activated fixtures setting each other off”.  According to Dommisse, with the new technology in the second generation fixture this has been solved and the maintenance is simple.

This low flow touch free fixture has a battery which has a life a 3 to 5 years. The fixture also has a sensor to minimize the faucet turning on when not needed.

The owner’s manual will need to have instruction for maintenance.

Shroades, Renee, “Restroom Revolution: Touchfree, Low-flow, Infrared and Waterless”, January 2007,
<www.facilitiesnet.com/ms/article.asp?id=5923&keywords=restroom,%20touchfree,%20low%flow,%infrared,%20waterless,%20plumbing> . (18 June 2007).

Shroades, Renee, “Restroom Revolution: Touchfree, Low-flow, Infrared and Waterless”, January 2007,
<www.facilitiesnet.com/ms/article.asp?id=5923&keywords=restroom,%20touchfree,%20low%flow,%infrared,%20waterless,%20plumbing> . (18 June 2007).

Kohler, “Kohler’s Extensive Portfolio of Water –Saving Products Raise the Bar for  Water Conservation”, (7 February 2007) <http://www.us.kohler.com/pr/pressrelease.jsp?aid=1170023203931>. (18 June 2007).

Water Efficiency-Showerheads

Case Study
Company- The Natural Abode – Low Flow Shower Head

A female student who works for Greendatabase.org has long hair and says if she takes a shower with a low flow fixture she needs to rinse her hair longer which uses more water. David Wilder, from Natural Abode which makes a 1 GPM shower head, stated that their faucet uses a super aerator which helps the shower feel like a standard shower at 2.5 GPM.   One of the problems he has experienced is that the aerator causes the water to take longer to heat up.  He also stated that he heard that the 1 GPM shower head works successfully in a Men’s locker room, but he could not remember which football team used it.  His suggestion was to use the 1 GPM fixture in the men’s bathrooms and the 1.5 GPM fixture in the women’s bathrooms.

Locating the water heater closer to the showers or installing an instantaneous hot water heater will solve the longer heating time associated with the 1 GPM shower head due to the aerator.

Kohler, “Kohler’s Extensive Portfolio of Water –Saving Products Raise the Bar for  Water Conservation”, (7 February 2007)  <http://www.us.kohler.com/pr/pressrelease.jsp?aid=1170023203931>. (18 June 2007).

Meier, Alan, “Low-Flow Showerheads, Family Strife, and Cold Feet”, August 1994
<www.homeenergy.org/archive/hem.dis.anl.gov/eehem/94/940712.html>  , (19 June 2007).

Wilder, David, interview with company’s representative, The Natural Adobe, 19 June 2007.

The Natural Abode,”Low Flow Shower Heads”,
http://www.thenaturalabode.com/houseapps/waterconser/Water_Conservation.htm> (19 June 2007).

Water Efficiency-Waterless Urinal

Case Study
Company- Kohler- Steward S Waterless Urinal

According to an article from Environmental Building News, November 2004, “Why Non-Flushing Urinals Fail (And How to Prevent those Failures), The US Merchant Marine Academy removed the waterless urinals from their dorms due to odor caused by these two reasons.

Dr. Michael Hoffman, Ph. D., Dean of the Graduate School at California Institute of Technology, indicates on the Sloan web site that there is more odor from a water urinal than from a waterless urinal; “The dual barrier systems provided in the Waterfree Urinals are predicted to be 500 times more effective against the back migration of sewer gases as compared to conventional P-Trap water barriers.”

Footnotes

M, N, “Why Non-Flushing Urinals Fail (And Hw to Prevent those Failures)”, Environmental Building News, November 2004.

Hoffman, Michael, “FAQ”,  (19 June 2007)<http://www.sloanvalve.com/183.htm.>, (19 June 2007). 

Water Efficiency-Rainwater Catchment Systems

A rainwater catchment system is based on collection of rainwater and gravity flow pressure principles. Rainwater runs off the roof of the building into rain gutters. The gutters channel the water and empty it into a standpipe. When the standpipe has reached its capacity, the overflow runs through a pipe and empties into a secondary system. Any other overflow drains to the public or private sewer system. Spigots are built into the bottom of the standpipe and a secondary storage cistern. The pressure of the water in the standpipe and the drum pushes the water out when the spigots are opened.

Advantages- Relatively inexpensive, flexible system, reliable, clean and easy to manage, easily designed and integrated into new construction.

Example

To configure our system we used the garage/shop roof, which measures 42'x48', pitched at about 1 to 2, as our collector. During a light rainfall we can collect 400 gallons in a day. During heavy rains we can collect 1500 gallons in a few hours. Our rule of thumb calculation for square footage vs. amount collected is about 400 gallons of water per 1" rainfall, on our 25x40 foot garage roof. 

Pros

Excellent back up system.
Can easily be tied into well water system.
Can be put inside a barn, large garage, or in a basement.
Water is still available if you have no power, though at diminished pressure.
Pumps can run off solar or 12 volt systems.
Tanks rarely freeze except in sustained extreme cold due to their thermal mass.
Easy to tie into solar water system.
Most of the system is accessible, rather than buried, so repairs are easy.
Few expensive components.

Cons

Aesthetically intrusive - you have to do something with big tanks.
May not meet local building code requirements for primary water source for new construction.
Requires more ground space than a well for the storage tanks and pumping system.
Requires a good sized roof.
Roof materials and airborne pollutants can pollute the rainwater.
Gutters require constant maintenance and cleaning.

Rainwater & Green Roofs

Is it possible to combine rainwater use with green roofs?

Most definitely, and it is a great way to save on additional costs.

With up to 50-90% of precipitation being retained by the green roof build-up any excess water can be collected and stored in a modern rain management system or cistern.

Another benefit is the vegetation and substrate layer acting as a water filter; these layers hold back particles, dust, solute pollutants, and even heavy metals.

The excess rainwater can then be used to irrigate the roof, used to flush toilet water, or any other available purposes. Water coming from the roof can have a light brown tint as a result of the humic particles in the substrate layer; therefore, it is not suitable to be used as wash water. If run-off water is used for toilets it is best to have a sign indicating ‘natural cloudiness’ in order to avoid confusion.

Calculating storage capacity: It should be noted that during the summer months most rainwater is used by the green roof itself and this should be incorporated into the calculation for the cistern. To make the final determination for the necessary storage capacity a professional for modern rainwater management systems (or similar professional) can be consulted.

HERE ARE SOME OTHER LINKS THAT MAY BE INFORMATIVE:

www.rainharvesting.co
http://www.ribaproductselector.com/Docs/7/11397/external/COL711397.pdf?ac=
http://www.co.ramsey.mn.us/NR/rdonlyres/2ACE0C58-C5E7-4C98-B182-37103BD69C9E/3753/StopWaterPamphlet061.pdf
http://www.thefarm.org/charities/i4at/surv/raincat.htm
http://www.zinco-usa.com/faq/faq7.html