innovative engineering the protecting barrier
TRANSCRIPT
50 ABB Review4/2004
Innovative Engineering
The protectingbarrier
Protecting the Eastern Scheldt flora and faunaArnold Kroon, Nils Leffler
51ABB Review4/2004
Innovative Engineering
A barrier was needed to protect
the Dutch coast and its hinter-
land from the fierce storms of
the North Sea, but such a barrier
would have destroyed a unique
estuary environment with all its
flora and fauna. A lively social
debate in the seventies led to the
Dutch parliament in 1979 ap-
proving the building of a storm
surge barrier with moveable
gates. These gates would allow
the microenvironment within
Eastern Scheldt estuary to be
maintained while protecting the
land from storms. In 1986 ABB
commissioned a complex redun-
dant system for the control of
the 62 gates of the barrier. After
18 years of failure-free service,
this system has been upgraded
to the modern Industrial IT archi-
tecture during the fall of 2004.
Bursting of the dikesIn February 1953, disaster struck. Alarge part of South-West Holland, espe-cially the province of Zeeland, was hitby the pounding surge of the North Seaflooding the lowlands and killing nearly2000 people. To avoid another catastro-phe of this magnitude, the Delta com-mission was appointed and within oneyear the Delta plan was enacted. Dikesand dams were built or strengthened to close off the raging and unrelentingsea. This ambitious public works pro-gram shortened the Dutch coastline by 700 kilometers, creating an entirelynew landscape of beaches, sandbars,lakes and recreational areas, all protect-ed from the tide and the sea by fixedbarriers. The Delta Works program wasimplemented along the coastline fromRotterdam to Antwerp during a period
of some 30 years. One of the last partsto be protected from the impact of the North Sea was the Eastern Scheldtestuary in the south of Holland .
Saving the Eastern Scheldt estuary The unique ecology of the EasternScheldt estuary became a political agen-da item during the 1970’s leading to an
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intense environmental debate. showsthe location of the estuary in the south-ern part of Holland. The clean saltyseawater provides rich feeding groundsfor many kinds of animals. Fish use theestuary as a nursery. Unique plantsgrow in this fertile microenvironment.Large-scale oyster, cockle and musselfarming also takes place there. Mudflats,
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Eastern Scheldt storm surge barrier with its unique sand dunes.1
Eastern Scheldt estuary with the storm barrier constructed in three parts between two islands.
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salt marshes and sandbars form an im-portant natural habitat for birds. It wasfelt that if the estuary was closed off bya dam and cut off from the tides, thesalt water would gradually turn fresh.
The estuarine flora and fauna would notsurvive. And the unique salt marsh andmudflat landscape would vanish. Salt-water fishing and mussel, cockerel andoyster farming would end. It was this
ecological and environmental debatethat led to the decision to build a StormSurge Barrier with movable gates ratherthan permanently dividing the estuaryfrom the sea.
The Storm Surge BarrierThe design selected has three barriersections between two islands. In totalthere are 62 movable steel gates ,each 45 meters wide. The gates aremounted between pillars resting on astrong foundation. Under normal weath-er conditions they are wide open allow-ing the tide to move freely. Duringsevere storms in the stormy season fromOctober to April, they are fully closed to protect the lowland from flooding(perhaps twice a year). Built to last formore than 100 years, the gates withtheir singular priority to close whenevera storm hits needed a complex redun-dant control system. ABB was given theorder for this in 1983 and Queen Beat-rix inaugurated the barrier in October1986.
The control systemEach gate is equipped with a LocalControl Computer system (LCC). Super-vising the 62 LCCs is a CCC – CentralControl Computer. The original orderfor the LCCs consisted of 252 MP100and 126 MP200 connected in a redun-dant configuration with an additional 8 MP200 and 4MV 850 for the CCC. The total installed I/O count exceeds25,000 signals. After 18 years of suc-cessful operation, the owner (the Gov-ernment of Public Works and Transport:department of Rijkswaterstaat or RWS),decided the time had come to modern-ize the system. In 2003, a revamp orderwas given to ABB Holland to replacethe old components with Industrial ITproducts.
In close cooperation with Mr. Jan Bos-land and Mr. Jan Lindenbergh from Rijk-swaterstaat, Directie Zeeland, an inven-tory of required activities was madeduring the stormy season, during which
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52 ABB Review4/2004
Innovative Engineering
The Eastern Scheldt storm surge barrier.3
Configuration of LCC with AC800 M units.4
Field – Digital Input (DI)
Safety closing circuit (DI)
QE22 – 2003 selector
Field – Digital Output (DO)
AC800M – 4x
QESI206
Command – DI
DisplayRS232
Lamps DO
SwitchControl Network
Local Panel
53ABB Review4/2004
Arnold Kroon
ABB Corporate Communications
Rotterdam, Netherlands
Nils Leffler
Chief Editor, ABB Review
Zürich, Switzerland
Innovative Engineering
period no major maintenance work ofthe barrier was allowed. The new solu-tion wasscheduled tobe in opera-tion by Octo-ber 2004. Astep by stepapproach waschosen inwhich eachgate isequipped with an engineered, producedand tested Industrial IT control panel.
The gates are refitted one at a time –this permits the closing of the gates dur-
ing the reno-vation in caseextremeweather con-dition in com-bination withhigh sea lev-els should oc-cur. In August2003, one of
the LCCs was replaced with the new In-dustrial IT control panel. depicts theLCC configuration with AC800M mod-ules which replace the old MP100 units.
After successful in-situ testing, ABBproceeded to install the other 61 panels.The complete task includes 250 AC800M controllers with Process Portal Aas HMI. The supervisory level was alsoreconfigured and modernized as part ofthe project. shows the configurationwhich replaces the old CCC system.
The software that had operated thegates for 18 years without failing had to
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be transferred to the new hardwarewithout having to reprogram all units.Being able to accomplish this was thekey factor for granting the revampingproject to ABB. Using CoLT (ControlLanguage Translator), the ABB Mastersoftware could be reused and RWS andABB secured the reliability of the barri-er, saving costs in software engineering.
Equipped for decades of serviceA poster, , used in the exhibitionroom at the Eastern Scheldt barrierspeaks of the trust RWS has placed inABB. In September 2004, the newIndustrial IT based control system tookover responsibility from the successfulold servant of 18 years.
The Eastern Scheldt storm surge barrieris now equipped with ABB’s new Indus-trial IT control system and is ready togo to battle during inclement weatherconditions and to protect the Dutch andtheir environment from flooding forseveral decades to come.
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The Eastern Scheldt stormsurge barrier is now equippedwith a modern control systemthat is ready to go to battleduring inclement weatherconditions.
CCC configuration.5
Hardcopyprinter
Plant Network
Aspect Server
Operate IT Connectivity Servers
4 x Control Network from LCC’s
Operate IT Process Portal (clients) Alarm & event printer
Control Network
BSS
EXCOM
PC-BSS
PC-Power
PC-Doors
Wall panel
R31 S16 H15R16R02
R01R18
R17S02
S01H02
H01
The water was up to here, Tom!– from a poster at the EasternScheldt visitor center.
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