reporter: the carnage you re describing sounds like something out of world war ii. yeah. o donnell: in tonight s eye on america, cbs ben tracy on how parts of the mighty mississippi now look like a desert and why that could impact the price of things you buy. and, the new york city bus driver being hailed a hero after a hijacking. this is the cbs evening news with norah o donnell, reporting from the nation s capital. o donnell: good evening to our viewers in the west and thank you for joining us. tonight, we return to a community still in pain, still searching for answers, and still wondering why it took police more than an hour to enter the classroom where a gunman was murdering fourth graders. at a hearing today, families had their first face-to-face confrontation with the texas public safety chief. he s the one in charge of the dozens of state troopers who waited in the hallway during the deadliest elementary school shooting in a decade. today, colonel s
worsening drought in the midwest water levels along the mississippi river are now at record lows. that could be catastrophic for businesses and consumers. in tonight s eye on america, cbs ben tracy shows us what s being done to keep commerce moving. reporter: the mighty mississippi might need a new nickname. north of memphis, it looks more like a desert than a river. barge traffic up and down this crucial corridor is slowed or stranded. economic costs are estimated to be in the billions. how bad are things on the river right now? it s stark. we are seeing operational challenges that are almost unprecedented. reporter: paul rhody represents the river shipping and towing industry. he says the mississippi is plunging to record-low levels, just as farmers send their harvests down-river for export. 1/12th of the world s population eats something that emanates from the mississippi river basin. 40% of the global food supply starts at the mississippi river basin.