Aging and undersized sewers, contaminated drinking water, and lead-tainted pipes imperil millions of households and communities nationally. At the same time, more severe flooding and drought conditions have exacerbated the nation’s water infrastructure deficit. Decades of inaction and underinvestment—particularly at a federal level—have multiplied these and other water infrastructure challenges, but the recently passed Infrastructure Investment and Jobs Act (IIJA) holds promise to address them via an infusion of more than $57 billion to states and localities over the next five years.