externalities

Aging US water infrastructure has meant more leaks, flooded basements, and massive sinkholes in cities across the US. Fixing the water and sewer systems in need of repair will take billions of dollars, and it's hard to find that kind of money in the budget these days. Saqib Rahim reports for ClimateWire on Philadelphia's decision to use "green infrastructure" rather than building a larger pipe system to handle the water that's dumped on the city during severe storms. The combination of more intense storms and more paved area is a problem: Impervious surfaces like roads, sidewalks, and…