This is a post we also did for The Wilderness Classroom.
Have you ever tried to build barriers to protect a
sandcastle from waves on an ocean beach? At a much bigger scale, this is the
same problem The Netherlands faces (The Netherlands is sometimes called
Holland and people from the Netherlands are the Dutch). Almost half the country is either below sea
level or less than 3 feet above sea level.
The three largest cities (Amsterdam, Rotterdam, The Hague) are all in
these low-lying regions.
Building a sand castle in a flood prone area |
While in the Netherlands, we visited the Zuiderzee (pronounced
zow-der zay) Museum, to see an exhibit about floods in Dutch history. We were amazed at the number of serious floods
the country has experienced. To protect their country from floods, the Dutch
have built many dikes, barriers, and pumps.
List of serious floods in Dutch history at Zuiderzee Museum |
Many Ways to Protect Against Floods: The Clever Dutch
The Dutch are threatened by flooding from both the sea and
from rivers. To keep low-lying land free
of water, they use dikes, which are walls that are built to keep water out. Along with the dikes, they use continuously
operating pumps. If the pumps stopped,
water would eventually seep back into low-lying land.
After a serious flood in 1916, they used one massive dike to
close off part of the ocean. The
Zuiderzee, an inlet of the North Sea, caused many floods. So the Dutch built a 20-mile (32km) long dike
to close off part of it off. When it was
completed in 1932, it created the largest freshwater lake in Western Europe,
called the Ijsselmeer.
Along the dike that holds in the Ijsselmeer |
Another strategy the Dutch use is called “room for water.”
Sometimes, they have to let water take over some land, in order to protect the
rest. This could be water from the ocean
or from rivers. With rivers, they make
“room for the river” by making sure rivers have plenty of bends -- straight
rivers can run too fast, eroding dikes quickly, with less time to react to
floods. They also create two dikes
around key waterways, an inner dike for normal water levels and an outer dike
in case water goes over the inner dike in a flood.
In addition, a key part of the Dutch’s strategy is a massive
series of barriers that close off water channels if water levels rise too
high: we visited one, called the
Maeslantkering (pronounced mahs-lahnt-caring).
The Maeslantkering
When you visit the Maeslantkering, the first thing that
strikes you is its size: it’s absolutely
enormous. It’s a set of huge curved doors
that block off the ocean when sea level rises too high. One arm that swivels the doors into place is
as long as the Eiffel Tower lying on its side – and it weighs twice as much!
One arm of the Maeslantkering – Eiffel Tower on its side! |
It weighs even more when it’s filled with water, which is
how it works. First the doors slide into
place over the channel. Then, water is
pumped into the hollow frame, which then sinks the doors into the channel –
making them extremely heavy and stable.
The Maeslantkering provides protection against sea level
rise of up to 5 meters (16 feet). The
gates are only closed if sea level is expected to rise at least 3 meters (10
feet). Except for an annual test, the
gates have been closed only once since being completed in 1997.
In front of the Maeslantkering |
The Maeslantkering is part of the Delta Project, a huge
system of dikes and storm surge barriers created to protect the southwestern
part of the Netherlands. The Delta Project was started following a major flood
in 1953 that resulted in 1,836 deaths and a lot of property damage, and caused
the Dutch to overhaul their water management.
How Could Climate Change Affect The Netherlands?
Two big challenges the Dutch face from the warmer temperatures
created by climate change are rising sea level and stronger storms.
Rising sea level: Warmer
temperatures cause glaciers and ice sheets to melt, with the water eventually
running into the oceans. In all the
glaciers and ice sheets of the world, there is enough water to raise sea levels
about 75 meters (about 250 feet). The
majority of glaciers and ice sheets are located in Greenland and
Antarctica. To date, sea levels have
risen about 8 inches, but forecasts are for it to rise between about 1 and 6 ½
feet by 2100.
Harriet glacier in Svalbard, Norway |
Stronger storms: Warmer
air can hold more moisture. Think about
the bathroom mirror steaming up after a warm shower (try a cold shower – the
mirror will be clear). According to the 2012 Yale forum on Climate Change and the Media, the Earth’s air
is about 4% more humid than it was 30 years ago. This added water in the atmosphere provides
more fuel for storms (there’s simply more water that can rain down). Plus, storms often form over oceans. Warmer oceans provide more fuel for storms
then colder oceans.
So rising sea level will be something the Dutch watch
closely over time, to make sure their barriers and systems provide adequate
protection.
The water management expertise the Dutch have built up over
the centuries will only become more and more valuable as rising sea levels and
more floods affect communities around the world. Already, the Dutch are sharing their
expertise, working with officials in New York, Vietnam (Mekong Delta), Bangladesh
and other places on water management plans.
Thanks
Many thanks to Alexander Verbeek (Strategic Policy Advisor
Global Issues, Ministry of Foreign Affairs, Netherlands), who I connected with
on Twitter several months ago, for his recommendations on places to visit in
the Netherlands. He also connected us
with Dr. Raimond Hafkenscheid (Strategic Advisor for Water and Adaptation,
Department of Climate, Energy, Environment and Water at the Ministry of Foreign
Affairs in The Netherlands). Dr.
Hafkenscheid graciously met with us and taught us about the Dutch approach to
water management. We also heard about an
amazing
event he recently organized: kids
building sandcastles. Why were they
building sandcastles? Watch the
video here to find out.
Study Guide Questions
1. What portion of the Netherlands is below sea level or
within 3 feet of sea level?
2. Describe why the Dutch have been dealing with virtual sea
level rise for a long time.
3. What are two challenges the Dutch face from climate
change?
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