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PERC, ASFlow provide drainline carry research update at WaterSmart Innovations

The Plumbing Efficiency Research Coalition, known as PERC, provided an update presentation on its activities and those of their partner organization, the Australasian Scientific Review of Reduction of Flows on Plumbing and Drainage Systems (ASFlow) Committee at the 2011 WaterSmart Innovations Conference in October. Both organizations are working on research programs that seek to investigate the impact of reduced water flows in sanitary drainage systems resulting from reductions in water use from plumbing fixtures and fittings, appliances and commercial and institutional equipment.

PERC was founded in 2009 to develop research projects that will support the development of water efficiency and sustainable plumbing products, systems and practices. The six member organizations of PERC are the Alliance for Water Efficiency (AWE); American Society of Plumbing Engineers (ASPE), International Association of Plumbing & Mechanical Officials (IAPMO), International Code Council (ICC), Plumbing-Heating-Cooling Contractors National Association (PHCC), and Plumbing Manufacturers International (PMI). PERC has identified drainline transport as its first research project. IAPMO’s Pete DeMarco serves as project coordinator for this inaugural research study and also chairs the technical committee assigned to the project assigned to the project. Each of the member associations of PERC has named a representative to this committee.

DeMarco, along with other coalition members in attendance, provided an update on the activities of the groups. Pete indicated that the research plan for the initial round of research testing had been completed, with studies planned on the impact of key variables like pipe slope, water closet flush speed and flush volume. An analysis of the data will rank significance of these variables and determine interactions between them. The objective of the research will be to determine the impact key variables impacting drainline carry, potential strategies for reducing clogging at various flows, and the effect of injecting large volumes of water for a short duration to clear accumulated blockages.

The coalition pointed out that the anticipated cost to conduct the research was estimated at $170,000. PERC has received several offers for potential testing locations and, pending funding, will assess each before announcing a selection. DeMarco commented that he hopes that the coalition will be sharing test results during WaterSmart 2012, but that is dependent on the group’s success in raising the remaining funds required.

Related testing
ASFlow has been conducting related testing in Australia through the support of the Australian Government and water utilities. Some of the most recent results of their work were summarized at WaterSmart as well. Most recently the group examined the impact of toilet paper variations on drainline carry. They tested 22 types of toilet paper available in Australia, with differing number of plies, weight and texture. Using a 60 M (200’) long drainline, their testing compared the carry of toilet paper samples using 4.5 L (1.19-gal.) and 3 L (0.8-gal) flush volumes. The results showed a very significant variation in the drainline carry between the best performing and worst performing toilet paper samples. Results degraded further when the various types of paper were tested with miso media. Further analysis of the data appeared to show a very strong inverse relationship between the wet tensile strength of the toilet paper and its drainline carry performance. The weaker the paper when wet, the farther it carried.

The presenters noted that both PERC and ASFLow planned continued data sharing and collaboration moving forward. DeMarco reiterated that PERC is continuing to seek funding to conduct their research program. PERC is hopeful that their program will receive funding and that work will commence in 2012.

For more information concerning PERC and their related research, please contact any of the coalition members. The presentation given at WaterSmart Innovations can be viewed on the WaterSmart website at:

Coalition member contacts are: Mary Ann Dickinson ([email protected]) at Alliance for Water Efficiency; Jim Kendzel ([email protected]) at American Society of Plumbing Engineers; Pete DeMarco ([email protected]) at International Association of Plumbing & Mechanical Officials; Jay Peters ([email protected]) at International Code Council; Gerry Kennedy (ken[email protected]) at Plumbing-Heating-Cooling Contractors; and Barbara Higgens ([email protected]) at Plumbing Manufacturers International.

Shawn Martin is director of industry relations of the Intl. Code Council, Plumbing Mechanical and Fuel Gas Group.