The document discusses various flood protection strategies used in Basel, Switzerland. It describes strategies such as weather forecasting, dam operations, river channelization, overflow channels, controlled flooding, widening rivers, afforestation, permeable pavements, and sponge cities. Many strategies have benefits of reducing flood risk but are expensive to implement and maintain. They can also impact the natural environment, availability of land, and appearance of rivers. Modeling floods helps improve flood protection for the city of Basel.

1. Basel Flood Protection: Summary
The pro’s and cons of Basel’s flood protection

2. Prediction is essential.
MeteoSchweiz weather forecast
FOEN monitor river levels and use
hydrographs to predict flood risk.
Basel Stadt
model floods to
improve
protection.

3. Prediction is essential.
Very expensive.
Requires access to satellite data and
highly trained meteorologists.
Make it harder to
build homes for
people living in
the city.

4. The Birsfelden Kraftwerk.
Produces electricity.
Controls the water level in the river .
Produces electricity for around 150,000 households,
17% of the total electricity consumption in Basel.

5. The Birsfelden Kraftwerk.
Very expensive.
Can prevent fish from migrating.
Have a large visual impact. Dramatically
change the appearance of the river.

6. Concrete embankments, Rheinweg, Central Basel.
Improves the city by making use of river side and
creating a great place for people to hang out. . Increases the height of the river bank,
therefore reducing the chance of flooding.

7. Concrete embankments, Rheinweg, Central Basel.
Very expensive.
Changes the natural appearance of the river
bank.

8. Speeds up the flow of
the water in the
channel, therefore
keeping water levels
down
Channel straightening
on the Rhine,
downstream of Basel
Created a channel that
ships can use
Allows the flood
plain to be used for
houses and farming.

9. Preventing flooding in
one area may increase
the risk of flooding
downstream. The
water has to go
somewhere.
Channel straightening
on the Rhine,
downstream of Basel
Changes natural
appearance of the river
Preventing flooding
means farmers must use
more fertilisers.
Very expensive.

10. Great for wildlife
Channel is left in a more natural state,
increasing the amount of water it can store.
Overflow channel, The Alter Rhein,
downstream of Basel

11. Needs a wide flood plain to give space for the
second channel.
Overflow channel, The Alter Rhein,
downstream of Basel
Less land for farming or building.

12. Speeds up the flow
of the water in the
channel, therefore
keeping water levels
down
Channel
straightening on
the Birsig,
central Basel
Increases the
depth and width
of the river so it
can contain more
water

13. Preventing flooding
in one area may
increase the risk of
flooding
downstream. The
water has to go
somewhere.
Channel
straightening on
the Birsig,
central Basel
Expensive

14. Controlled flooding / Water Meadows, Biel
Benken & Therwil
Areas are often left in a more natural state,
increasing the amount of water it absorb.
Encourages wildlife and
increases biodiversity.
Flooding is good for the land.
The sediment left behind by the flood,
fertilises the soil and makes it better for
growing food.

15. Controlled flooding / Water Meadows, Biel
Benken & Therwil
Results in large areas of land being flooded.
Some the damage to property may occur.
Does not stop the flood occurring only reduces
the impacts.
Reduces the land available for building.

16. Provides areas for people to sit and improves
access to the river.
Creates a green space in a built-up area.
Increases the depth and width of the river so it
can contain more water , therefore reducing the
chance of flooding.
The channel is widened, and earth banks are
created.
The Birs, Birsfelden

17. Reduces the land available for building. Needs to be constantly checked and repaired as
the river naturally wants to meander.
The channel is widened, and earth banks are
created.
The Birs, Birsfelden

18. Sandbags, can be
used anywhere.
A very quick
and easy
method of
flood
defence.
Allows temporary barriers
to be built, therefore
reducing the damage to
property

19. Sandbags, can be
used anywhere.
Does not stop
the flood
occurring only
reduces the
impacts.

20. Great for
wildlife
Reduces the amount of water getting into the
river, as the trees intercept water by their
leaves or soaking it up in their roots.
Reduces the amount of soil washed away that
could reduce the depth of the river.
Afforestation on the
Gempen

21. Does not stop the flood occurring
only reduces the impacts.
Large area needed to plant the trees.
Reduces the land available for building.
Afforestation on the
Gempen

22. Permeable Pavers, Basel
Stadt Allows water to
soak into the
ground.
Is part of a much
bigger idea to
create Sponge
Cities.

23. Sponge Cities
Designed to absorb, capture and store rain water.
Reduces risk of
flooding.
Creates more green
space in cities.
Source of drinking
water
Cools down city