A recent National Science Foundation study on water affordability found that roughly 13.8 million U.S. households could not afford to pay their water bill in 2014. The study found that while access to water has remained relatively affordable until recently, water rates have increased around 41 percent in just the past seven years. Should the rate hikes continue at this pace, according to the report, more than one-third of all U.S. households—35.6 percent—will be unable to afford running water by 2022. One American city, Philadelphia, has taken measures to address this challenge through a new program—the Tiered Assistance Program (TAP). Enrollees' monthly water bills are not based on consumption but rather set as a percentage of household income and size. Eligible households are provided with water conservation education along with free leak detection tests and low-flow plumbing fixtures. Using data collected from income-based gas & electric utility programs in New Jersey, Pennsylvania and Colorado, consultants are predicting that Philadelphia's water department will see a net gain in revenue as a result of lowering the rates and increasing compliance. Perhaps this new approach can be a model for others to follow in addressing a widening water affordability gap. Interested in assessing affordability at your utility? Here is an easy-to-use Excel tool courtesy of UNC Environmental Finance Center to assess the relative affordability of water & wastewater rates using multiple metrics. Interested in learning more about customer assistance programs (CAPs), how to fund them, legal hurdles and their expanding importance? Listen to this podcast featuring Stacey Isaac Berahzer from The Environmental Finance Center at the University of North Carolina at Chapel Hill (EFC).