Water is considered the most important natural resource in the four Pacific Northwestern states (Alaska, Idaho, Oregon and Washington). Public attitudes about water resource issues and needs were deter- mined using a mail-based survey instrument every 5 years (2002, 2007, 2012 and 2017). The survey questions were identical over the 15-year period. The statistically designed survey study was also designed to measure change over the 15-year time period. Four specific survey questions were evaluated in this article. In 2017, over 83% of the public considered their home drinking water safe; however, this value was lower and compared unfavourably to the 93.1% who considered their drinking water safe in 2002. In 2017, 43.8, 40.7, 28.3, 25.3, 19.4 and 14.8% of residents considered phosphates, nitrates, pesticides, pharmaceuticals, petroleum products and pathogens as problems in local waters, respectively. Compared to the 2002 survey, the perceived problem of phosphates, nitrates and pharmaceuticals has become worse; however, public views of problems caused in waters by pesticides and petroleum prod- ucts have lessened. Based on public perception, the problem of pathogens in waters has not changed over the 15-year span. Surface water and groundwater quality were considered to be excellent or good by 51.6 and 46.2% of survey respondents in 2017, respectively. In general, public views of water quality have improved since 2002.
drinking water, public concerns, public opinion, water contaminants, water quality, water quantity
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