During the 1970s and 1980s, Congress distributed more than $60 billion to cities to make sure that what goes into toilets, industrial drains and street grates would not endanger human health.

Around New York City, samples collected at dozens of beaches or piers have detected the types of bacteria and other pollutants tied to sewage overflows. Though the city's drinking water comes from upstate reservoirs, environmentalists say untreated excrement and other waste in the city's waterways pose serious health risks.

As cities have grown rapidly across the nation, many have neglected infrastructure projects and paved over green spaces that once absorbed rainwater.

Charles Duhigg Quotes