Drinking water systems imperiled by failing infrastructure
![Drinking water systems imperiled by failing infrastructure](http://bloximages.chicago2.vip.townnews.com/tdn.com/content/tncms/assets/v3/editorial/d/34/d34afcae-8b1c-56c0-a58e-21e2e2b74e10/5606b37248512.image.jpg?resize=300%2C200)
DES MOINES, Iowa (AP) — Deep inside a 70-year-old water-treatment plant, drinking water for Iowa's capital city is cleansed of harmful nitrates that come from the state's famously rich farmland.