Drinking water systems imperiled by failing infrastructure
![Drinking water systems imperiled by failing infrastructure](http://bloximages.chicago2.vip.townnews.com/bismarcktribune.com/content/tncms/assets/v3/editorial/2/fb/2fb9077c-e0c5-5c25-b67f-31f9036bd582/5609f6c8a27fa.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.