The data on plumbing facilities were obtained from Housing Question 9 in the 2006 American Community Survey. The question was asked at both occupied and vacant housing units. Complete plumbing facilities include: (a) hot and cold running water, (b) a flush toilet, and (c) a bathtub or shower. All three facilities must be located inside the house, apartment, or mobile home, but not necessarily in the same room. Housing units are classified as lacking complete plumbing facilities when any of the three facilities is not present.
The 1996-2006 American Community Survey questions were stand-alone questions that asked the respondent to answer either Yes, has all three facilities or No to the question of whether the housing unit had complete plumbing facilities, requiring that the facilities all be in the same unit. Starting in 2006, the structure of the question changed and combined plumbing facilities with kitchen facilities and telephone service availability into one question to ask, Does this house, apartment, or mobile home have - and provided the respondent with a Yes or No checkbox for each component needed for complete facilities. An additional change introduced In 2006 included changing the description of the component hot and cold piped water to hot and cold running water.