Switching to the Flint River as the city’s primary water source was an attempt to save around $5 million over the course of two years in Flint, Michigan.

Instead it has cost $458 million.

That’s according to calculations from analyst Peter Muennig at Columbia University's Mailman School of Public Health. Only $58 million of that is expenditure by the state on medical care and unleaded water. The bulk of the number includes the social costs: Exposures leaking IQ points from children and disposing them to aggression and violence later in life, which leads to lower economic productivity, greater dependence on welfare programs, and greater costs to the criminal justice system.

The lifelong bill for each case of low-level lead poisoning is about $50,000 and 0.2 years of perfect health, based on CDC data. Flint has already seen more than 8,000 documented exposures, while each year there are some 90,000 across the country. When it comes to low-level exposure, Muenning and many others believe that drinking-water is the most common source. Chewing on paint tends to cause higher lead levels.

Muenning explained to me that while the chain of events may not be immediately evident, it’s important to follow backward as a matter of avoiding a common fallacy: considering the costs of action (primarily in economic and financial terms) while ignoring the costs of inaction. Those costs can be rendered in the interest of maximizing human well-being or simply protecting a municipal bottom line, depending on one’s priorities.