Are We Color Blind?

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.