>> Reporter: VENICE IS A WORLD

CLASS WONDER.

A CITY BUILT ON MORE THAN 100

SMALL ISLANDS, CONNECTED BY A

MAZE OF BRIDGES AND CANALS. THE

THE LARGEST IS THE GRAND CANAL

WITH ITS FAMOUS RIALTO BRIDGE.

OVER THE CENTURIES, VENICE HAS

STOOD THE TEST OF TIME, BUT

TODAY THIS ISLAND CITY IS UNDER

SIEGE LIKE NEVER BEFORE, FROM"

RISING" SEAS AND A "FLOOD" OF

TOURISTS.

>> THE FACT THAT WE ARE STILL

WAITING FOR ANY KIND OF SOLUTION

OF THESE PROBLEMS OF TOURISM AND

FLOODING IS DEEPLY DEPRESSING.

ALSO HOW MUCH THE WATER LEVEL

HAS RISEN.

>> Reporter: HISTORIAN MONICA

CHOJNACKA WAS BORN IN VENICE AND

PROUDLY CALLS THIS CITY HER

HOME.

>> THAT WAS THE STEP YOU GOT ON

WHEN YOU GOT OFF OF YOUR GONDOLA

OR YOUR BOAT TO GET INTO THE

HOUSE.

>> Reporter: BUT SHE'S CONCERNED

ABOUT ITS FUTURE.

>> THIS IS A STEP THAT, OF

COURSE, WHEN IT WAS BUILT WAS

NEVER DESIGNED TO BE SUBMERGED

IN WATER.

NOW IT'S ALWAYS UNDERWATER EVEN

IN THIS RELATIVELY LOW TIDE.

>> Reporter: "ACQUA ALTA,"

MEANING HIGH WATER, HAS ALWAYS

BEEN A FACT OF LIFE HERE.

SEVERAL TIMES A YEAR, HIGH TIDES

AND STORM SURGES FLOOD THE CITY,

ESPECIALLY THE FAMOUS PIAZZA SAN

MARCO.

THE WORST FLOOD OCCURRED IN

NOVEMBER 1966, WHEN THE VENICE

LAGOON ROSE MORE THAN SIX FEET

ABOVE SEA LEVEL.

AFTER THE DELUGE, THE CITY

DESIGNED AN ALERT SYSTEM WHICH

HAS KEPT PACE WITH THE TIMES.

>> WHAT HAPPENS IS WE ARE

ALERTED VIA AN APP AS WELL AS

TEXT MESSAGES AND IN ADDITION,

WE HAVE SIRENS THAT ARE BLASTED

THROUGH THE CITY.

(SIRENS WAILING)

>> Reporter: THOSE WARNING

SIRENS ARE COORDINATED FROM THIS

COMMAND CENTER ON THE GRAND

CANAL.

A SIREN IS FOLLOWED BY PITCHED

WHISTLES.

ONE WHISTLE MEANS ABOUT 12% OF

THE CITY WILL BE FLOODED, WATER

IS ANKLE DEEP, AND SHOPKEEPERS

BARRICADE THEIR DOORS.

TWO WHISTLES MEAN THE WATER WILL

BE HIGHER.

ALMOST ONE-THIRD OF THE CITY

WILL BE FLOODED.

>> THREE MEANS RUN FOR THE

HILLS, BECAUSE IT'S GOING TO BE

HIGH!

>> Reporter: VENETIANS GENERALLY

TAKE "ACQUA ALTA" IN STRIDE.

LIKE THE MANAGER OF THE GRAN

CAFFE LAVENA, MASSIMO MILANESE.

HE SHOWED US PICTURES OF HIS

CAFE DURING A RECENT FLOOD.

TABLES AND CHAIRS SITTING IN THE

WATER.

>> SEE THE SPECIAL DOOR HERE.

>> Reporter: LIKE OTHERS IN THE

PIAZZA, HE HAS FLOOD DOORS TO

PROTECT HIS BUSINESS.

HE TOOK US BEHIND THE CAFE,

WHERE THOSE FLOOD DOORS ARE

STORED.

SO THE WATER CAN ACTUALLY GET

THIS HIGH?

>> THE MAXIMUM THAT I SAW--

THIS.

>> Reporter: WHOA.

SO JUST A COUPLE OF INCHES MORE,

AND THIS WOULD HAVE BEEN

USELESS.

HE ALSO KEEPS WATERPROOF BOOTS

ON HAND FOR HIS EMPLOYEES.

ACQUA ALTA EVENTS ARE USUALLY

LESS THAN BOOT HIGH, LAST JUST A

FEW HOURS, AND THE CITY CLEANS

UP AND GOES BACK TO NORMAL.

BUT FLOODS ALSO EAT AWAY AT THE

SOFT, PERMEABLE BRICKS THAT SIT

ABOVE THE FOUNDATIONS OF THE

BUILDINGS.

OVER TIME, VENETIANS HAVE RAISED

THEIR DOORWAYS AND IN SOME CASES

ABANDONED THEIR GROUND FLOORS.

BUT THE FLOODING IS GETTING

WORSE AS THE WATER LEVEL IN THE

ADRIATIC SEA AND VENICE LAGOON

RISES DUE TO CLIMATE CHANGE.

THE SEA LEVEL ALONE HAS RISEN

FIVE AND HALF INCHES SINCE 1900,

ACCORDING TO CITY OFFICIALS.

THE ITALIAN GOVERNMENT DOES HAVE

A PLAN TO PROTECT VENICE.

IT'S CALLED THE MOSE PROJECT.

CONCEIVED IN THE 1970s, IT'S A

SERIES OF 78 UNDERWATER GATES

SECURED TO THE FLOOR OF THE

VENICE LAGOON.

DURING ESPECIALLY HIGH TIDES,

THEY WILL BE PUMPED WITH AIR AND

RISE TO THE SURFACE TO BLOCK

RISING WATER FROM REACHING THE

CITY.

FOUR GIANT BARRIERS ACROSS THREE

INLETS ARE SCHEDULED TO BE

OPERATIONAL BY 2019.

IS MOSE ABLE TO DEFEND VENICE?

>> YES, MOSE WILL BE ABLE TO

PROTECT THE CITY OF VENICE FROM

EXCEPTIONALLY HIGH WATER.

THAT MEANS WATER THAT EXCEEDS

3.5 FEET ABOVE SEA LEVEL.

>> Reporter: SO THIS IS WHAT THE

GATE LOOKS LIKE WHEN IT'S DOWN?

>> YES, THIS IS THE GATE WHEN IT

IS STANDING ON THE BOTTOM OF THE

INLET.

>> Reporter: DARIO BERTI IS

ENGINEERING AND PRODUCTION

MANAGER WITH THE COMPANY

BUILDING THE MOSE PROJECT.

CONSTRUCTION BEGAN IN 2003,

TESTING IN 2013.

IF THIS IS THE FIRST PROJECT OF

ITS KIND, HOW CAN YOU BE SO SURE

THAT IT'S GOING TO WORK?

>> WELL, THIS IS THE RESULT OF

YEARS AND YEARS OF PLANNING AND

EXPERIMENTS ON MODELS, TRIALS IN

TANKS.

IT'S BEEN TESTED IN ALL POSSIBLE

CONDITIONS.

SO, WE'RE CERTAIN IT WILL WORK.

>> ONE QUESTION ABOUT THE MOSE

PROJECT, THESE SEAWALLS, IS

WHETHER IT WILL BE EFFECTIVE?

>> Reporter: IF IT WILL BE

EFFECTIVE?

THEY'VE SPENT BILLIONS OF EUROS

ON IT.

SHOULDN'T IT BE EFFECTIVE?

>> YES, THE LATEST ESTIMATES ARE

BETWEEN $5 BILLION AND $6

BILLION EUROS HAVING BEEN SPENT

ON THIS PROJECT.

CERTAINLY A PORTION OF THAT

MONEY HAS NOT GONE TOWARDS THE

BUILDING OF THIS PROJECT BUT

RATHER TOWARDS PAYOFFS TO LOCAL

AND REGIONAL POLITICIANS AND

BUSINESS FOLK.

THREE YEARS AGO, ABOUT 35 OF OUR

LEADING CITIZENS WERE ARRESTED

ALONG WITH OUR MAYOR.

>> Reporter: THE MAYOR OF VENICE

WAS ARRESTED?

>> THE MAYOR OF VENICE WAS

ARRESTED AS WELL ON CHARGES OF

CORRUPTION CONNECTED TO THIS

PROJECT.

>> Reporter: A VERDICT ON THE

CASE OF THAT FORMER MAYOR IS

EXPECTED THIS FALL.

CONSIDERING THE CORRUPTION

SCANDALS, ENVIRONMENTAL

SCIENTIST JANE DA MOSTO SAYS THE

ITALIAN GOVERNMENT SHOULD HAVE

GONE BACK AND REVIEWED THE

ENGINEERING AND SCIENTIFIC BASIS

FOR MOSE.

>> THERE HASN'T BEEN ANY KIND OF

TECHNICAL REVIEW ABOUT WHETHER

OR NOT THEY ARE DOING THE RIGHT

THING, AND THAT I DO FIND

SERIOUSLY ALARMING.

>> Reporter: DA MOSTO IS

EXECUTIVE DIRECTOR OF A

NONPROFIT GROUP CALLED "WE ARE

HERE VENICE," WHICH IS TRYING TO

RAISE AWARENESS OF THE

CHALLENGES FACING VENICE.

SO THERE'S A LOT OF CONCERN

AMONG VENETIANS THAT THE WORK AT

MOSE ISN'T BEING DONE PROPERLY?

>> IT'S NOT JUST AMONGST

VENETIANS.

ARTICLES HAVE BEEN PUBLISHED IN

NATIONAL NEWSPAPERS,

INTERNATIONAL JOURNALS.

THEY HAVE A PROBLEM ABOUT SAND

GOING INTO THE INDENTATIONS IN

THE LAGOON FLOOR, WHERE THE

PANELS THEN HAVE TO LIE BACK

DOWN AGAIN.

THEY FOUND THAT THE HINGES,

THEY'VE STARTED CORRODING MUCH

SOONER THAN THEY THOUGHT THEY

WOULD.

THEY ALSO KEEP DELAYING WHEN

THEY SAY IT'S GOING TO BE READY.

NOT A GOOD SIGN.

>> Reporter: MOSE ENGINEERS SAY

THEY ARE ADDRESSING THE ISSUES

OF SAND OBSTRUCTING THE BARRIERS

AND OF RUSTING HINGES.

BUT LUCA ZAGGIA, FROM THE

INSTITUTE OF MARINE SCIENCES

NATIONAL RESEARCH COUNCIL OF

ITALY, WARNS ASSUMING THEY WORK,

THERE'S A LIMIT TO HOW MANY

TIMES THE DEFENSIVE FLOOD

BARRIERS CAN BE DEPLOYED BEFORE

THEY DAMAGE THE LAGOON.

HOW MANY TIMES CAN YOU RAISE THE

FLOOD BARRIERS IN A YEAR?

>> WE SAY TEN TIMES A YEAR IS

THE BEST AMOUNT.

MAYBE 15 OR 20, BUT NO MORE.

>> Reporter: BUT THE CLIMATE IS

CHANGING, THE WATER LEVEL IS

RISING.

WHAT HAPPENS 20 YEARS FROM NOW,

30 YEARS FROM NOW?

IS THAT STILL GOING STILL TO BE

THE CASE?

>> NO. SURE.

WE WILL CLOSE MORE FREQUENTLY.

UP 100 TIMES A YEAR.

>> Reporter: 100 TIMES A YEAR?

WHAT IS THAT GOING TO DO TO THE

LAGOON?

>> IT WILL BE A TERRIBLE

DISASTER FOR THE ECOSYSTEM.

STAGNATION FIRST AND THEN

CONTAMINATION AND GROWTH OF

MICROALGAE.

>> Reporter: IT SOUNDS VERY

HARMFUL.

>> YEAH, IT IS.

YOU CAN HAVE MASSIVE DEATHS OF

FISHES IN SUMMER.

>> Reporter: MOST TOURISTS ARE

OBLIVIOUS TO THE BARRIER SYSTEM

AND SERIOUSNESS OF THE FLOODING

PROBLEM.

THEY ARE BUSY TAKING SELFIES,

MARVELING AT THE BEAUTY OF THIS

CAR-FREE CITY, OR TRYING TO

ESCAPE FROM THE SUMMER HEAT,

LIKE THESE TOURISTS FROM IRELAND

WE FOUND IN THE SHADE OF THE

TOWER IN PIAZZA SAN MARCO.

THEY HAD NO IDEA, UNTIL WE TOLD

THEM, THIS PLAQUE MARKS THE

HISTORIC FLOOD OF 1966, WHEN THE

WATER LEVEL WAS SO HIGH, THEIR

CHILDREN WOULD HAVE BEEN NECK

DEEP.

>> Reporter: THE 25 MILLION

TOURISTS WHO VISIT EVERY YEAR

ARE ACTUALLY ANOTHER MAJOR

THREAT TO VENICE.

SOUVENIR SHOPS AND HIGH-END

BOUTIQUES CATERING TO THEM HAVE

REPLACED VEGETABLE STANDS,

HARDWARE STORES, AND OTHER SHOPS

NECESSARY FOR DAILY LIFE.

HOUSING PRICES HAVE SOARED WITH

SPECULATORS BUYING UP PROPERTY

TO RENT TO TOURISTS.

AS A RESULT, VENETIANS ARE

MOVING AWAY.

AT THE END WORLD WAR TWO, THERE

WERE 150,000 FULL-TIME RESIDENTS

OF VENICE.

NOW, THERE ARE ONLY 54,000.

ON SOME DAYS, THERE ARE ACTUALLY

MORE TOURISTS THAN RESIDENTS,

AND THAT UPSETS VENETIANS LIKE

MATTEO SECCHI.

>> THE VENETIAN WAY OF LIFE IS

AT RISK, SIMPLY BECAUSE WE'RE

VANISHING.

THERE'S ALWAYS FEWER OF US.

WE'RE LOSING OUR CULTURE.

BECAUSE WHEN A VENETIAN LEAVES

THE CITY, HE DOESN'T JUST LEAVE

THE CITY, HE LEAVES A WAY OF

LIFE AND CULTURE.

>> Reporter: IN THIS FRAGILE

CITY, SOME RESIDENTS SAY HUGE

TOURIST CRUISE SHIPS ARE MAKING

MATTERS WORSE.

TOMMASO CACCIARI IS THE FOUNDER

OF THE GROUP "NO GRANDI NAVI,"

MEANING "NO LARGE SHIPS."

IT WANTS TO BAN LARGE CRUISE

SHIPS FROM ENTERING THE VENICE

LAGOON.

>> THERE'S A MASS AMOUNT OF

WATER THAT PUSHES BACK AND

FORTH.

IT'S CALLED SIPHONING.

IT'S LIKE AN ACCORDION THAT

SUCKS THE FOUNDATION OF THE

CITY.

THERE'S NO CONCRETE UNDER HERE.

THERE'S MUD, SOFT MATERIAL THAT

GETS SUCKED OUT.

>> Reporter: THIS PIER, HE SAYS,

REBUILT SEVEN YEARS AGO, IS

ALREADY SHOWING SIGNS OF DAMAGE

FROM THE CRUISE SHIPS.

WHEN THEY PASS BY, THEY CREATE

THIS HUGE PRESSURE THAT

BASICALLY SUCKS THE SEDIMENT OUT

FROM UNDERNEATH US AND ACTUALLY

LOWERS THE FOUNDATION.

YOU CAN SEE IT REALLY RIGHT

BEFORE YOUR EYES HERE WITH THESE

BRICKS HERE.

THE CRUISE SHIPS EMPLOY FIVE

THOUSAND VENETIANS, BUT THE

VENICE PORT AUTHORITY SAYS ONLY

ABOUT A QUARTER OF THEIR

PASSENGERS GET OFF THEM AND

SPEND MONEY IN THE CITY.

REINING IN THE SHIPS AND THE

TOURISTS IS ONE CHALLENGE HUMANS

CAN CONTROL.

CONTROLLING THE SEAS IS NOT.

WHICH IS WHY MARINE SCIENTIST

LUCA ZAGGIA IS PUTTING HIS FAITH

IN THE MOSE PROJECT TO SAVE

VENICE FOR FUTURE GENERATIONS.

SO THE SYSTEM MUST WORK.

THE ALTERNATIVE IS WHAT?

>> THE SYSTEM MUST WORK.

WE HAVE NO ALTERNATIVES AT THIS

POINT.

IT HAS TO WORK.