Over the last three years, the American Water Works Association (AWWA), the Water Environment Federation (WEF), and the WateReuse Association (WRA) have been working with the two plumbing code organizations [International Association of Plumbing and Mechanical Officials (IAPMO) and
International Code Council (ICC)] to change their 2009 plumbing code requirement regarding purple pipe use for any alternate water delivered on private property. A white paper was presented to IAPMO in August 2009 proposing to use green pipe with black text to identify onsite alternate waters,
including graywater, which is untreated wastewater. Many industry professionals with backgrounds in the water utility industry found the proposal to be logical and supported it; however, the plumbing code and building code professionals rejected it, based on the Plumbing Code requirement for
the color green to designate potable water in buildings. The American Public Works Association (APWA) Uniform Color Standard and the Common Ground Alliance - Best Practices Guide designate the color green to represent sewers, storm sewer facilities or other drain lines. For most wastewater
professionals, green is commonly used for polyvinyl chloride (PVC) sewer pipe with green strips on high-density polyethylene (HDPE) pipe. Likewise, wastewater utilities that also operate potable water systems typically use the color blue to indicate potable water. In an attempt to promote
the use of purple pipe, discussions have resulted in conflict and little uniformity with respect to color selection for the two most divergent waters, from a public health perspective. It could be assumed that WEF Manual of Practice (MOP) 8 could solve this problem; however, on review of this
document, a clear answer was not discovered. Chapters regarding safety do not identify reclaimed water pipe, but do call for non-potable, seal water or diluting water pipe to be color-coded purple; non-potable fire hydrants are also to be color-coded purple (Table 10.25). In further conflict,
Chapter 8 identifies purple to designate radiation hazards. Green color coding can indicate compressed air or non-potable process or flush water, while blue colored pipe is designated for potable, domestic or chilled water. If construction and maintenance at a wastewater plant is intended
to follow one of the two national plumbing codes, then the WEF guidance manual creates several conflicts with plumbing codes. This paper will describe the significant cross-connection potential that exists today, due to historical installation practices and inconsistent color code requirements
within utility organizations and between professionals in parallel code development roles. A plan is proposed for utilities and plumbing code officials to work with several state regulatory agencies to develop a common color code for reclaimed water, wastewater and potable water, in the interest
of public health.
Proceedings of the Water Environment Federation is an archive of papers published in the proceedings of the annual Water Environment Federation® Technical Exhibition and Conference (WEFTEC® ) and specialty conferences held since the year 2000. These proceedings are not peer reviewed. WEF Members: Sign in (right panel) with your IngentaConnect user name and password to receive complimentary access.