yeah. nightly news is next followed by giants baseball and then local news at 11:00. >> see you then. good night. on this saturday night, search and rescue. fighting the deadly floods in colorado where almost 800 are taken to safety by air and land. among them, dozens of children trapped while on a field trip. as authorities try to locate hundreds more. art of the deal. after only three days the u.s. and russia reach an unprecedented agreement on removing syria's chemical weapons. tonight what it means and the broader challenge of ending the civil war. turning a page in this library of the future. you can read all about it as long as it's not on paper. and music down under. we'll see and hear why tens of thousands are heading deep underground for a sound like no other.

good evening. surging floodwaters have already trapped hundreds around boulder colorado and are threatening more communities tonight. these pictures captured by a drone show what residents and rescuers are up against. the death toll is at least four. officials caution they have yet to account for the whereabouts of many living in the flood zone potentially cut off by roads left impassable or washed away. an airlift operation is under way bringing some left stranded to safety. through it all there have been dramatic, heart-stopping rescues. our team remains in place. joe fryer leads off our coverage tonight from boulder. joe? >> good evening, lester. all the rain from the past week is still surging through rivers and creeks across colorado. and in some spots, that's creating more dangerous situations.

no relief tonight from rapidly rising waters. as overflowing streams pour through even more parts of colorado. >> it is no doubt an epic event, a once in a 500 to 1,000-year storm. >> reporter: this is the scene in the town of greeley, the river's edge rests a third of a mile from here. neighbors built a berm to keep waters from their homes. >> i started pushing up dirt, trying to block it. soon the highway washed out and the water just started receding. >> reporter: for the second straight day stranded jamestown residents are air lifted to boulder by national guard helicopters -- the only way out of town. >> water is rushing through a canyon where everyone lives. it destroyed houses in minutes. >> reporter: they clutch everything they can, flown into a place that's typically just a 14-mile drive. >> it was one of the most surreal experiences anyone could imagine. >> reporter: images from a drone

offer a glimpse of what's off limits on the ground including roads that vanish into massive piles of mud. even tall rigs like this firetruck struggle to plow through the record high torrent. one of those killed was hit by a mudslide. >> the gentleman who lives at the bottom of that was taken. >> reporter: it's been hard on the entire town. meantime the boulder colorado sheriff's department says 350 people are still unaccounted for. >> we are assuming some of them are still stranded. we are assuming there may be further loss of life or injuries. we have to assume that. >> reporter: they hope most are just stranded without communication. someone who is accounted for, roy ortiz, rescued after spending two hours in his submerged car. >> so i had to pray. i want to survive. >> reporter: stories like this are offering hope to a state

just struggling to stay above water. joe fryer, nbc news, boulder, colorado. >> reporter: this is lee anne gregg in colorado. a joyful reunion today. parents and children reunited in louisville. 85 5th graders trapped by flooding while on a school field trip near jamestown were finally airlifted to safety. >> parts of it were scary and the trails were basically rivers. >> every time you watch the news it's hard not to burst into tears. >> reporter: while 15 miles away at an evacuation center in longmont, more reunions. a story of another dramatic rescue. thomas and debra casey and their dog airlifted from home after a helicopter crew saw their signal for help. >> we painted s.o.s. on the driveway. not an hour later. >> reporter: in boulder, laura and marty were awakened by crashing mud against their home. they heard a car horn outside.

they looked and saw a vehicle swept away with four teenagers inside. sadly, two were among those killed. but combs was among a group of them able to. rescue one of them. in a remarkable twist, hours later, laura, expecting her first baby, went into labor. >> started feeling contractions and thought, oh, no, i'm not going into labor. this is not the right time. >> reporter: with no way out emergency crews arrived and transported her to a hospital. baby ingrid was born shortly after. back in louisville and across the region families are grateful just to be together. >> we'll let them get away with more today. [ cheers ] >> reporter: the kids on the trip designed to help practice teamwork got the ultimate lesson. rescuers hope for more successful outcomes like this in the coming days. lester? >> lee anne gregg and joe fryer starting us off. thanks to both of you. let's bring in weather channel meteorologist mike seidel in boulder. this flood is expanding.

more communities in danger tonight, right? >> yes. more heavy rain on the radar. we have heavy rain on the foothills west of here and the front range in metro denver. the storms prompted additional flash flood warnings. they are dumping one to two inches of rainfall of water. with the ground saturated from rain this week that is running off. the concern in the higher terrain, more mud slides, rock slides, debris floes. this threat will continue through tomorrow. by the first of the week, drier air descends on colorado and new mexico. we think it will be rain free most of next week. in boulder creek we have made real progress today. the water dropped two feet. but the big change is since the peak of the flash flood on thursday night, the flow through here dropped a whopping 90%. lester? >> i know folks will take any good news you can give them. mike seidel, thank you. now to the crisis in syria which in a week has gone from the threat of an imminent american attack to an

unprecedented agreement to remove syria's chemical weapons. at least that's the plan. nbc's chief foreign affairs correspondent andrea mitchell has been covering the talks since thursday in geneva. tonight she's back in washington. good evening. >> reporter: good evening, lester. it is a breakthrough agreement that the u.s. hopes will set the stage for future political negotiations to end the civil war. first, even top u.s. officials tonight are wondering whether syria's president assad will comply with today's retirement that he disclose all of his chemical weapons and their secret locations in just a week. after three days of round-the-clock meetings -- openly emotional sighs of relief. but in announcing the details of the agreement secretary of state john kerry and sergey lavrov say the work has just begun.

>> the implementation of this framework which will require vigilance and investment of the international community and full accountability of the assad regime presents a hard road ahead. >> translator: we understand the decisions we have reached today is only the beginning of the road. >> reporter: hours before around the geneva hotel swimming pool, kerry, lavrov and top aides hammered out final details over coffee and handshake, reaching a four-page agreement and a calendar of specific goals. in a week syria must tell where the chemical weapons and where they are. in november syria must provide independent international inspectors unlimited access to its entire chemical arsenal and an initial report on their findings must be issued by the end of the month. by mid 2014, all chemical weapons and material must be destroyed or removed from syria. it won't be easy, as nbc's ian williams reports from geneva. >> this is an incredibly ambitious agreement. one senior u.s. official

described it as daunting to say the least. the first key test comes in just a week when syria is required to come up with a full accounting of its chemical stockpile. >> reporter: president obama, briefed by national security adviser susan rice issued a statement welcoming the agreement and saying again the threat of u.s. military force opened the way to a diplomatic solution. in his weekly media address the president pledged to follow both courses. >> we will maintain our military posture in the region to keep the pressure on the assad regime. >> reporter: but the white house gave up on including force as part of a u.n. position. they cited russia's opposition reiterated by lavrov again today. >> translator: of course in this approach if we don't there is nothing said about the use of force. >> reporter: today john mccain and lindsey graham said the plan is meaningless without a u.s. threat of force and does nothing to resolve the underlying civil war. privately the russians told the u.s. they are speaking for assad.

that remains to be seen. secretary kerry already had to call turkey's prime minister today after they slammed the agreement for letting assad off the hook. u.s. officials say they expect delays if this works eliminating syria's huge stockpile of chemical weapons would be a huge benefit to the world. >> all right. andrea, thanks. we want to look at how the agreement is playing out in syria where the clock is now ticking on the assad regime and where the war goes on. bill neeley is in damascus for us tonight. >> reporter: damascus is reeling from the speed of the deal and events. remember, not long ago this city faced american air strikes. no one here is completely happy with the deal. on the government side, people i have talked to clearly prefer it to air strikes. but they find the timetable very tight. president assad wanted 30 days to list his chemical weapons. he's been given seven.

the clock is ticking. no official reaction from the president or his government yet. remember, he did say, i want to get rid of chemical weapons. but that's the key question. does anyone trust him? on the rebel side, they don't like this deal at all. the opposition leader says he re -- rejects it. he says the russians and syrians are playing games to waste time for a criminal regime. he's pledged that rebel fighters will keep up this war. it goes on behind me tonight with the syrian army continuing to shell rebel-held suburbs. opposition people say dozens of citizens have been killed in the last 24 hours and the battle in the christian town of malula goes on. so a deal is done, but the war goes on. back to you, lester. >> bill neeley in damascus tonight. back in this country, in ohio they are looking for the cause of a bus crash early this morning.

a greyhound bus went off a highway north of cincinnati. it struck a tree and a fence and flipped on its side before stopping in a corn field. at least 35 people were injured including the driver. one passenger said he saw the driver slumped over before the crash and heard a woman screaming at him to wake up. a part of the jersey shore this day was spent searching for clues about what might have caused the devastating fire that destroyed part of a newly renovated boardwalk and dozens of businesses recovering from super storm sandy. michelle franzen is in seaside heights tonight. >> reporter: well, lester, the charred boardwalk behind me stretches for blocks. and tonight ocean county prosecutors tell us that the cause of the blaze is still unknown and the start of the fire they have not determined if it was foul play or oh accidental. meantime, the fire also burned the hopes of many living in this community who rely on this iconic spot for their livelihood.

digging in and digging deep. a team of arson and fire investigators began sifting through sections of the burned-out seaside park boardwalk, still smoldering in spots today. seaside heights police chief tom boyd says the trained team isn't ruling anything out. >> whether it's good or bad, the atf, state fire marshals will get to the bottom of what happened here. i have full faith in that. just like reading an x-ray. >> don't go in there. >> reporter: witnesses captured this video of the fire breaking out near a kohr's frozen custard stand. the stretch of boardwalk included three dozen businesses that went up in flames. owners like domenic marucca was flooded out by super storm sandy said he poured his life savings into rebuilding maruca's pizza which just re-opened less than four months ago. >> i will get with my professional people. we'll look at the dollars and cents and then the emotional loss. >> reporter: business owners met

town leaders and governor chris christie today to determine what's next. >> we had two days to feel sad about this. it is legitimately a sad thing. we have work to do now. >> reporter: officials say it will cost $1.6 million to repair the boardwalk and millions more for business owners to rebuild. >> i lost my business. i can't even put a figure on it. >> i have to feed my family, my kids. this is how we do it. we depend on the people who come back and support us once we are open. >> reporter: the determination still there. >> you have to have a sustainable base, people coming to your place. i don't get a paycheck or the economy doesn't run. to see the devastation here it kicks us back another level. >> reporter: even in the path on how to get there is unclear. that emotional toll may be the toughest hurdle for the community. counselors have been brought in to help owners and workers out of a job cope with the

devastation and loss. lester? >> michelle franzen, thank you. when "nbc nightly news" continues on this saturday, checking out the library of the future where a book is the one thing you can't take out. later if you like music, we'll take you to a place where everything sounds so much better on a stage millions of years old.

we are back with a sign of the times. the opening of a new public library today in texas.

that may not seem like big news but it is notable for what's missing -- books. at least the kind on paper. it's one of the first libraries of its kind. we sent janet shamlian to brows arouns. >> you will want a pass word. >> reporter: it looks like an apple store. rows of shiny computers. >> you would say reader apps. that's where you want to go. >> reporter: there is nothing to buy here. the bibliotech is a new public library. if they're on vacation, on the break at work, they can browse the entire collection and choose what they want to read right there. >> reporter: there are 10,000 titles but not a single hardcover or paperback. every book is digital. >> we fell in love with e-books, but it is expensive to be constantly purchasing them. the idea of borrowing them from the library is very appealing to us. >> reporter: for those without an e-reader, there are 600 for

loan. they turn off if not returned. for all that a paperless library offers it can't offer the ability to wander the stacks, browse the aisles and make a test test test test test test test test test test test test test test test test test test test test test test a traditional library, and allows those who can't get to the building to use its resources. >> i don't need to build a 250,000-square-foot central library. less cost. can't give you everything you may want, but we are giving you a lot. >> reporter: for children tablets can be checked out, preloaded with books and interactive games. >> i was skeptical. before i had this job i worked as a high school english teacher. so i like books. i like things you can hold. this is the way things are going. >> you enter your card information.

>> reporter: a new library test drives virtual borrowing as reading goes from paper to pixels. janet shamlian, nbc news, san antonio. >> when we come back, the latest chapter in a saga at sea.

it happened two years ago this coming january. the costa concordia cruise ship ran aground off the tuscan coast of italy. today preparations were made for an attempt on monday to finally move the ship upright. machines will try to roll it off the bottom onto an underwater platform made of steel girders and cement. then workers will look for the bodies of two people still missing. in texas the six flags

amusement park re-opened the rollercoaster from which a woman fell out and plunged to her death this summer. the ride has new seat belts and redesigned pads on restraint bars. riders will be able to see how they fit in a test seat before getting on the rollercoaster. the woman's family filed a wrongful the death suit against six flags. the company says the investigation found no mechanical failure on the ride. in new jersey, a moving moment today at the rutgers football game honoring number 52 eric le grand. three years after he was paralyzed from the waist down while making a tackle the team retired his number during a halftime ceremony, the first time it happened in the team's history h. for his part le grand made a plea to the crowd to support research to find a cure for paralysis. up next tonight a trip to the underground for a real musical and visual treat.

finally tonight why would anyone journey into a cave with bats 300 feet below the surface of the earth just to hear a little music? our report tonight from nbc's kevin tibbles in tennessee. >> reporter: you could call them subterranean sounds. ♪ >> reporter: to hear them, one must journey toward the center of the earth. have you ever played music? >> no.

>> reporter: this is like majestic. >> this is insane. ♪ >> reporter: once a month visitors to the cumberland caverns hear tunes usually reserved for above ground in nearby nashville. how far does this go back? >> we have 28 miles of mapped caverns. >> reporter: formed by a vast, ancient underground network of rivers. >> all the water rushing through the rock, opening up vast rooms inside the mountain here. >> reporter: just imagine 333 feet 'below the earth's surface and before your eyes, a crystal chandelier and an underground spectacle. ♪ >> reporter: the largest cave provides musicians and 500 listeners with near perfect acoustics. >> it's one of the most special places. it sounds incredible in here. it really does. >> reporter: although some sneak

a listen for free. are there bats down here? >> we do have bats. >> reporter: oh. ♪ >> ricky skaggs walked on stage and said, it's hanging room only. looks like bats. [ cheers and applause ] >> reporter: the cave music is so popular pbs now broadcasts it. ♪ bluegrass underground featured ricky skaggs, vince gill and leon russell. ♪ >> reporter: every piece of equipment must be carted into the deep. >> this is an experience you just don't have in life no matter if you are playing or walking around. you don't find yourself 300 feet below the surface of the earth. ♪ >> reporter: a concert hall like no other above or below terra firma.

kevin tibbles, nbc news, cumberland caverns, tennessee. that's "nbc nightly news" for this saturday. i'm lester holt reporting from new york. i'll see you tomorrow morning on "today." then right back here tomorrow evening. good night.

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