The Plumbing Efficiency Research Coalition, comprised of five plumbing trade groups, will make drain line transport its first research project. The coalition is made up of the Alliance for Water Efficiency; the International Association of Plumbing & Mechanical Officials; the International Code Council; the Plumbing-Heating-Cooling Contractors – National Association; and the Plumbing Manufacturers Institute.
Since the advent of 1.6-gallon per flush toilets in 1992, many plumbing
professionals has voiced concern on whether the restricted flushes provide
enough water for drain line transport of waste.
Recently, high efficiency toilets, which use even less water per flush and
other toilets that use just 1 gpf, have raised these concerns again,
particularly for larger commercial systems and their long horizontal runs to
the sewer. Drain line transport problems have already been reported in Europe
In addition to low-flow toilets, waterless urinals, greywater systems and other
appliances that use less water means that much less water is being discharged
into drainage systems.
To date, an extensive research project of sufficient scope to be able to
determine if significant problems could arise regarding drain line transport
has yet to be conducted.
will serve as project coordinator for this inaugural research
study and will also chair the Technical Committee assigned to the project. Each
of the five member associations of PERC has named a representative to this
committee. The first order of business is to define the parameters of the