Keeping the water away
New approaches to flood control
A. Recently, winter floods on the rivers of central Europe have been among
the worst = severe for 600 to 700 years, and dams and dykes (protective
sea walls) have failed to solve the problem. Traditionally, river engineers
have tried to get rid of the water quickly, draining it off the land and down
to the sea in rivers reengineered as high-performance drains. But however
high they build the artificial riverbanks, the floods keep coming back. And
when they come, they seem to be worse than ever
B. Engineers are now turning to a different plan: to sap the water’s
destructive strength by dispersing it into fields; forgotten lakes and floods
plains. They are reviving river bends and marshes to curb the flow, and
even plugging city drains to encourage floodwater to use other means to
go underground. Back in the days = in the past when rivers took a
winding path to the sea, floodwaters lost force and volume while
meandering across flood plains and inland deltas, but today the water
tends to have a direct passage to the sea. This means that, when it rains in
the uplands, the water comes down all at once.
C. Worse, when the flood plains are closed off, the river's flow downstream
becomes more violent and uncontrollable; by turning complex river
systems into the simple mechanics of a water pipe, engineers have often
created danger where they promised safety. The Rhine, Europe’s most
engineered river; is a good example. For a long time engineers have
erased its backwaters and cut it off from its plain = isolated. The aim was
partly to improve navigation, and partly to speed floodwaters out of
Alps and down to the North Sea. Now, when it rains in the Alps, the peak
flows from several branches of the Rhine coincide where once they arrived
separately, and with four-fifths of the Lower Rhine's flood plain barricaded
off, the waters rise. The result is more frequent flooding and greater
damage. The same thing has happened in the US on the Mississippi river,
which drains the world’s second largest river catchment into the Gulf of
Mexico. Despite some $7 billion spent over the last century on levees
(embankments) the situation is growing worse.
D. Specialists in water control now say that a new approach is needed - one
which takes the whole landscape into consideration. = consider something
To help keep London's feet dry, the UK Environment Agency is reflooding
10 square kilometres of the ancient flood plain of the River Thames outside
Oxford. Nearer to London, it has spent £100 million creating new wetlands
and a relief channel across 16 kilometres of flood plain. Similar ideas ate
being tested in Austria, in one of Europe's largest river restorations to
date. The engineers calculate that the restored flood plain of the Drava
River can now store up to 10 million cubic metres of floodwater, and slow
down storm surges coming out of the Alps by more than an hour,
protecting towns not only in Austria, but as far downstream as Slovenia
and Croatia.
E. The Dutch, for whom preventing floods is a matter of survival, have gone
furthest. This nation, built largely on drained marshes and seabed, has had
several severe shocks in the last two decades, when very large numbers of
people have had to be evacuated. Since that time, the Dutch have
broken one of their most enduring national stereotypes features
by allowing engineers to punch holes in dykes. They plan to return up to a
sixth of the country to its former waterlogged state in order to better
protect the rest.
F. Water use in cities also needs to change. At the moment, cities seem to
create floods; they are concreted and paved so that rains flow quickly into
rivers. A new breed of ‘soft engineers’ wants cities to porous, Berlin is one
place where this is being done. Tough new rules = legislation for new
developments mean that drains will be prevented from becoming
overloaded after heavy rains. Architects = DESIGNER of new urban
buildings are diverting rainwater from the roofs for use in toilets and the
irrigation of roof gardens, while water falling onto the ground is collected in
ponds, or passes underground through porous paving. One high-tech urban
development can store a sixth of its annual rainfall, and reuse most of the
rest
G. Could this be expanded to protect a whole city = large scale? The test case
could Los Angeles. With non-porous surfaces covering 70% of the city,
drainage is a huge challenge. Billions of dollars have been spent digging
huge drains and concreting riverbeds, but many communities still flood
regularly. Meanwhile this desert city ships water from hundreds of
kilometres away to fill its taps and swimming pool. Los Angeles has
recently launched a new scheme to utilise floodwater in the Sun Valley
section of the city. The plan is to catch the rain that falls on thousands of
driveways, parking lots and rooftops in the valley. Trees will soak up water
from parking lots; houses and public buildings will capture roof water to
irrigate gardens and parks, and road drains will empty into old gravel pits
to recharge the city's underground water reserves. Result: less flooding
and more water for the city. It may sound expensive, until we realise
how much is spent trying to drain cities and protect areas from flooding,
and bow little this method achieves.
Questions 1-6
Reading Passage 2 has seven paragraphs, A-G,
Which paragraph contains the following information?
Write the correct letter. A-G, in boxes 1-6 on your answer sheet
1 how legislation = rule has forced building designers to improve water use F
2 two reasons why one river was isolated from its flood plain C
3 how natural water courses in the past assisted flood control B
4 an example of flood control on one river, affecting three countries D
5 a country which has partly destroyed one of its most typical features in order to
control water E
6 the writer's comment on the comparative cost effectiveness of traditional flood
control and newer methods G
