on the broadcast tonight, ripple effect. the fallout from the flooding on the mississippi river. tonight we'll show you how it's impacting the whole country and why millions are going down the drain. family secret. a shocking new confession from arnold schwarzenegger. he fathered a child with a woman who worked in his home. education nation. twin crises for new college grads. jobs hard to come by and now student debt hard to get rid of. and coffee talk. what the latest big study is saying tonight about how coffee may help reduce the risk of a major cancer killer. may help reduce the risk of a major cancer killer. "nightly news" begins now. captions paid for by nbc-universal television

good evening. a lot of water is flooding into louisiana. surging in now, following the opening of floodgates designed to do just that, flood one area to spare another. there's still a lot of water on the way. and high water will be with us for weeks. water will be straining against those levees and walls for some time. the mississippi river is changing as the flooding is rearranging life on land and overrunning parts of the bayou. the experts now tell us the impact from these floods could go as high as $2 billion. a big hit for industries like catfish, cotton, corn, wheat, beans, rice, the shipping industry that relies on the river as a central artery. we want to start off again tonight with nbc's anne thompson. she's in melville, louisiana. hey, anne. good evening.

>> reporter: good evening, brian. these waters are the superhighway of commerce. and the flood is causing a traffic jam. and that's costing money. as the swollen mississippi thundered south, high water forces the closing of the river to barge traffic at natchez, mississippi. the coast guard wants to reduce the water pressure on the levees. but in doing so it will increase pressure on the economy. the mississippi is a crucial economic artery. the barges carrying the ingredients that nourish and power america and the world. >> it's not going to mean the end of barges going through. but it's definitely going to put a delay there. and anytime you have delays there's cost incurred. >> reporter: costs are already climbing down river in louisiana. nine of the terrell river service's ten barges are tied up. high waters closed the locks they use to get to the mississippi and made the atchafalaya river unsafe to navigate. operations manager billy martin says the idle barges mean a loss

of some $54,000 each day they don't work. >> how long can you go on without running your boats? >> i don't know. we need those boats to be running as soon as possible. >> until they tell us we've got to go, we're not going anywhere. >> reporter: in the morganza spillway the water may not be rising as fast as expected, but fred montgomery says it is rising over acres of farm land. >> right down the road we've got another 600. >> and it's all underwater? >> everything's underwater. >> reporter: the gates of the morganza opened saturday and flooded these fields. part of the projected $300 million louisiana farmers will lose. >> this is a spillway. this is what it's meant to do, and this is what it's going to do. >> i'm waiting on the water. >> reporter: bradley grimmet grows corn and soybeans on 700 acres in the spillway. but with no soybeans planted, he says the flood has already cost him $200,000 and could get worse. >> whatever the water does controls what will happen to us. you know. but we stand to lose everything,

actually. >> reporter: now, bradley grimmet is not alone. economists say that americans could pay higher food prices because of the flood. but it's the people here that may pay the highest price of all. brian? >> anne thompson starting us off in louisiana. could not be a sadder story for so many folks down there. anne, thanks. now we turn to the story that so many people in this country woke up to this morning. the shocking revelation that arnold schwarzenegger, the former governor of california, has a child with a former household employee. nbc's miguel almaguer reports tonight from los angeles. >> a shocking public confession. >> reporter: california woke up today to a bombshell. >> i, arnold -- >> reporter: the state's former governor, arnold schwarzenegger, acknowledged he fathered a child with a member of his household staff. it happened more than ten years ago. an apparent reason why wife maria shriver left the couple's brentwood mansion before they announced their separation last week.

schwarzenegger says he told his wife after he left the governor's office. "there are no excuses and i take full responsibility for the hurt i have caused. i have apologized to maria, my children, and my family. i am truly sorry." according to the "l.a. times" schwarzenegger financially supported the mother and child from the very start. she's said to have worked inside the family home for 20 years and retired in january. shriver released her own statement. "this is a painful and heartbreaking time. as a mother, my concern is for the children." in new york reaction from shriver's cousin, patrick kennedy. >> i talked to maria. she's terrific. love her to death. >> reporter: married in 1986, schwarzenegger and shriver have four children. the infidelity, says schwarzenegger, happened before he ran for political office in 2003. >> and this is why i'm going to run for governor of the state of california. >> reporter: accused of womanizing and sexual harassment

at the time, it was maria shriver who then passionately defended her husband. >> you can listen to people who have never met arnold or who met him for five seconds 30 years ago, or you can listen to me. >> it was absolutely critical for maria to be there, standing by her man after the groping allegations. it blunted those allegations. >> reporter: the governor's indiscretion remained secret for over a decade. >> i think he's just so disgusting. i just wish i could take my vote back. >> reporter: now it's the talk of the town. a man who many believe betrayed his wife and the trust of the state he once ran. miguel almaguer, nbc news, los angeles. and here in new york today new twists and turns in that sex crime case involving one of the world's most powerful bankers and a housekeeper at a manhattan hotel. both sides are speaking out through lawyers about what did or did not happen there. nbc's jeff rossen is outside the

rikers island lockup, where dominique strauss-kahn is locked up tonight without bail. jeff, good evening. >> reporter: hi, brian. good evening to you. law enforcement sources now telling nbc news that dominique strauss-kahn, the leader of the imf, the international monetary fund, the man who may have become france's next president, is on suicide watch here at rikers island. that means no shoelaces. that power suit he used to wear has been replaced by a gray sweatsuit and sneakers as well. they check on him every 15 to 30 minutes. we also learned much more today about the criminal case against him. police say they have forensic evidence including dna showing that he did in fact sexually assault the hotel maid at a luxury hotel in midtown manhattan over the weekend. in court yesterday the defense hinted they may have an explanation for that, the fact that it was consensual, they both agreed to the sexual encounter. but late today the maid's lawyer spoke out, saying no question about it, this was 100%

forcible. >> there is nothing, nothing about what took place in this hotel room that could any way be construed as consensual either physical contact or sexual contact. absolutely none. he can make any allegation he wishes to make. but that's simply not the truth. and that won't -- that will never prevail as evidence in this case. >> reporter: as we mentioned, police have collected dna from the hotel. they have also collected dna from dominique strauss-kahn himself, brian. that dna is now in the lab. they're trying to get a match. results aren't in yet. there's another hearing on friday. but for now he remains here at rikers without bail. >> jeff rossen over at rikers island not far from laguardia airport here in new york tonight. jeff, thanks. to presidential politics now. and as our friends at our nbc news political unit reminded us today, it was just two days ago on "meet the press" with david gregory that former speaker of the house newt gingrich said the central test he's going to face

in the 2012 campaign will be whether or not he has the discipline and the judgment to be president. well, in just the last 48 hours it's been a rough go. a tough rollout for mr. gingrich. and some conservatives have already said he's failing his own test. nbc's andrea mitchell with us tonight from our d.c. newsroom with more on this story. andrea, good evening. >> reporter: good evening, brian. newt gingrich wanted to kick off his presidential campaign with a big splash. now it looks as though the only one getting drenched is the candidate himself. >> are you announcing right now? >> reporter: he announced less than a week ago on twitter and facebook. no chance for gaffes. >> i'm newt gingrich. and i'm announcing my candidacy for president of the united states. >> reporter: but on "meet the press," his first big interview, gingrich sided with liberals, slamming fellow republican paul ryan's plan to cut medicare costs. >> i don't think right-wing social engineering is any more desirable than left-wing social engineering. i don't think imposing radical change from the right or the left is a very good way for a

free society to operate. >> reporter: ryan shot back. >> with allies like that who needs the left? >> reporter: and now fellow conservatives are taking numbers to attack gingrich. >> he cuts paul ryan off at the knees. it supports the obama administration. >> reporter: headlining an editorial, "gingrich to house gop: drop dead," the "wall street journal" wrote today, "mr. gingrich chose to throw his former allies in the gop house not so much under the bus as off the grand canyon rim." the former speaker was even confronted by one critic in iowa. >> what you just did to paul ryan is unforgivable. >> i didn't do anything to paul ryan. >> yes, you did. you undercut him. you're an embarrassment to our party. >> i'm sorry you feel that way. >> why don't you get out before you make a bigger fool of yourself? >> i'm sorry you feel that way. >> this is one of those cases where a candidacy is almost imploding before the candidate leaves the starting gate. >> reporter: and now there's this. politico has dug up these financial records showing that gingrich owed tiffany's hundreds of thousands of dollars for unpaid bills back in 2005 and 2006.

a lot of debt to a high-end jeweler. gingrich's spokesman tonight had no comment. brian? >> all right. andrea mitchell in washington tonight. andrea, thanks. we turn to health news tonight. you know the rule of thumb on all those medical studies that come out? if you don't like the findings, wait for the next one. it's sure to have the opposite finding. well, tonight there's news about coffee. and if you're a coffee drinker, we think this is a study you'll like. it's a big one. it comes from the harvard school of public health. and it seems to hold strong evidence that coffee can help prevent prostate cancer. our report from our chief science correspondent, robert bazell. >> hey, how are you doing today? >> reporter: at sip the experience coffee shop in atlanta and around the country today men were glad to hear about the new findings. >> before i thought it was really bad for your health, you know, to drink a lot of coffee. so that's good news. >> it gives me even more of an incentive to drink coffee.

that's for sure. >> reporter: researchers at the harvard school of public health studied almost 48,000 men for 12 years and found that drinking up to six cups of coffee a day lowered the risk of prostate cancer. >> the strongest association was actually for prevention of advanced-stage or lethal prostate cancer. and there we found that the men who drank the most coffee had 60% lower risk of developing lethal prostate cancer during follow-up. >> reporter: surprisingly, the study found no difference between regular and decaffeinated coffee. if not caffeine what is the cause? previous research shows coffee beans contain antioxidants, anti-inflammatory compounds, and chemicals that help control blood sugar and hormone levels. but here's what's puzzling. 30 years ago the same laboratory that studies epidemiology, the causes of disease, found that drinking coffee increased the risk for a different deadly cancer. >> a new medical study out today indicates that coffee drinking may be related to cancer of the pancreas.

>> reporter: the harvard researchers later said those results were wrong. but this time they say the study got it right. >> like almost all sciences over the last 30 years, epidemiology has become much better, much more powerful in its methods. >> reporter: the scientists say even this latest study needs to be repeated. but at the very least men can go ahead and enjoy a daily cup or more of coffee. robert bazell, nbc news, new york. when our broadcast continues for you here tonight, "education nation." and why some are asking a provocative question -- is college even worth it? and later this evening, an event today so many people thought they would never live to see.

time now for tonight's look at "education nation," and a

topic here that's growing more urgent by the day. massive student loan debt that can ruin the lives of young college graduates just trying to get started. a student loan is one of the few types of debt you can't get rid of by declaring bankruptcy. you're stuck with it for life. now soaring tuition, huge loan burdens have many in our education nation wondering if college is even worth the try. the story from our chief education correspondent, rehema ellis. ♪ >> reporter: college commencement. a time of great expectations. and for many students great debt. federal student loans now add up to $800 billion, exceeding credit card debt. >> it's not cheap. >> reporter: daniel park and six other seniors at burbank high school in california are thinking about managing future expenses now. >> raise your hand if you'll be taking out a loan to pay for the cost of college. >> reporter: they all got accepted to colleges costing on average $50,000 a year.

but anxious about debt, isabel navarro decided not to go to her dream school. she will attend a community college instead. >> i don't want to graduate with a bachelor's degree with $80,000 worth of debt. >> reporter: a choice kelly space wishes she had made. she graduated with $200,000 in student loans. >> that's, you know, $1,000 payments for the next 25 years, possibly more if interest rates increase. >> reporter: students are borrowing more because college tuition and fees jumped 24% while family incomes dropped nearly 2%. huge student debt, experts say, affects decisions long after graduation. >> whether you buy a house. when you get married. whether you're saving. how much you're saving. and if you can afford to put your kids through school. >> reporter: helping students avoid staggering loan debt, tidewater community college in virginia now requires students applying for loans to create a detailed repayment plan.

>> it's the same thing all of us do when we take out a loan for any major purchase or investment. >> college debt was something you thought about? >> yes. absolutely. i made the choice to avoid loans. >> reporter: these students are taking stock of college expenses now so they can enjoy graduation later. rehema ellis, nbc news, los angeles. up next here tonight, somebody was watching our broadcast very closely. they saw an idea here that's going to be making a difference for a lot of other folks.

you're looking right now at how one of the worst months for tornadoes ever in this country looked from space. a noaa satellite captured images of the storm systems that swept across the south during april. we've sped it up here and put it on a continuous loop. 625 tornadoes have been confirmed. each one represented on this

map, when you look hard at it, as a red dot. of course, the worst of it was april 27th, 28th. more than 300 people were killed in over 180 separate twisters from texas to virginia. it's a mesmerizing look to take a nice long look at. you can see the whole thing on our website tonight, nightly.msnbc.com. and forgive us here for taking a brief slight bow for airing a story that might end up affecting a lot of people. it was a "making a difference" segment we aired about two years ago about a cafe in denver that let patrons pay whatever they could afford. a lot of you wrote to us reacting to it. turns out the chairman of the panera bread company was watching and he was inspired to open a branch outside st. louis in the clayton suburb a year ago yesterday where customers pay what they feel is fair. they've since opened two more panera cares restaurants, one in dearborn, michigan, the other in

portland, oregon. an idea we were happy to highlight originally when we first heard about it. we'll bring you a full follow-up report right here monday night. one of the great names in baseball is gone. more importantly, one of the great players of all time has died. harmon killebrew, the pride of the minnesota twins, retired as the fifth leading home run hitter of all time. his career average was .256. a lot of folks at the time called him the killer. but pitcher gaylord perry called killebrew ma bell because he hit the ball a long distance. he's the fifth hall of famer to die in just the past year or so. he follows guys like feller, duke, and sparky to their great reward. it should also be noted that he died with the same grace he displayed on the field. he issued a statement when he entered hospice for esophageal cancer saying calmly and clearly, "i have exhausted all options with respect to controlling this awful disease.

my illness has progressed beyond my doctors' expectation of a cure." well, that's why they placed a photo of him beneath home plate today. it's why there's sadness in the twin cities and all over. harmon killebrew was 74 years old. up next here tonight, a visit many thought would never happen.

finally here tonight, as we said earlier, a visit many thought would never happen. the queen of england today visited ireland. and while it's not quite nixon to china, and while london to dublin is just a short flight, it's something a lot of people never thought they'd see in their lifetime because of the troubles between the two neighbors that go way back. from dublin tonight nbc's john yang reports on a trip that was indeed a long time coming. >> reporter: just a few years ago this would have been unthinkable. the queen of england welcomed on independent irish soil, wearing emerald green, no less. the last british monarch to visit here, king george v, 100 years ago.

in between there's been a bloody war of independence and decades of conflict called the troubles over britain's continued control of northern ireland. the queen herself lost a beloved cousin. lord mountbatten, killed by an i.r.a. bomb on his fishing boat off the irish coast in 1979. today as an irish military band played "god save the queen," queen elizabeth laid a wreath at the memorial to irish rebels killed at the hands of british forces. >> now we've reached the point in our nation's history that we're comfortable in our own skin, we can bring the monarch of great britain over here and still realize that we're an irish nation and we can be proud of that. >> reporter: polls show most irish welcomed the visit. still, some want a united ireland with the british out of the north. >> we don't want the queen of england in any part of our country. we say to her, you can keep your apologies. take home your soldiers. >> reporter: security is tight. 8,000 police. that's 2/3 of all the police in ireland. the cost, a reported $40 million. a bigger operation than what's planned for next week, when president obama visits.

for all the queen's reign, really for all of her 85 years, ireland and britain's relationship has been marked by tragedy. today there was hope that those troubles have finally been put to rest. john yang, nbc news, dublin. and that is our broadcast on a tuesday night. thank you for being here with us. i'm brian williams. and we hope to see you right back here tomorrow evening. and we hope to see you right back here tomorrow evening. good night. -- captions by vitac -- www.vitac.com right now at 6:00, the lies and cheating and the secrets that arnold schwarzenegger has held for a decade. this is not the only mess in this remol dead. i'm kris sanchez. the story coming up. plus, another round of rain socking the bay area. how it could impact wildlife. the news at 6:00