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Adapting to climate change:

examples from the Netherlands

Workshop SDTA, ICID 26th ERC and 66th IEC, October 11-16, 2015, Montpellier, France

Henk Ritzema,

Wageningen University, The Netherlands

The Netherlands

Combination of

sea level rise

and subsidence

25% below sea level

65% would be flooded in

absence of dikes

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Agricultural development water management

In the past windmills

were used to drain

the land (left),

nowadays sluices

and barriers are used

to protect the land

against flooding

(right)

Water management

Land use

Climate change predictions:

Sea-level rise

Increase in river flow

Increase in winter precipitation

Higher risk of coastal flooding

Decrease in summer precipitation

Increase in temperatures

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Sea level rise and subsidence:

nothing new, but at a higher rate

Predicted sea level rise:

2100: 0.65 and 1.3 m

2200: 2 to 4 m

Predicted subsidence:

2100: 0.5 – 1.0 m

Pumping Dutch Polders to MSL -6m

- 5 m

0 m

+ 5m

Elevation in

m+ MSL

Den Haag

North Sea

Markermeer

A12

A4

A2Haarlem

A6

AmsterdamUtrecht

A13

A9A7

Waddenzee

Noordwijk

Delft

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- 5 m

0 m

+ 5m

Den Haag

North Sea

Markermeer

A12

A4

A2Haarlem

A6

AmsterdamUtrecht

A13

A9A7

Waddenzee

Noordwijk

Delft

Dutch Polder Landscape is inundated at MSL

Elevation in

m+ MSL

- 5 m

0 m

+ 5m

Den Haag

North Sea

Markermeer

A12

A4

A2Haarlem

A6

AmsterdamUtrecht

A13

A9A7

Waddenzee

Noordwijk

Delft

Pumping Dutch Polders to MSL -2m

Elevation in

m+ MSL

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5

- 5 m

0 m

+ 5m

Den Haag

North Sea

Markermeer

A12

A4

A2Haarlem

A6

AmsterdamUtrecht

A13

A9A7

Waddenzee

Noordwijk

Delft

Pumping Dutch Polders to MSL -4m

Elevation in

m+ MSL

Pumping Dutch Polders to MSL -6m

- 5 m

0 m

+ 5m

Den Haag

North Sea

Markermeer

A12

A4

A2Haarlem

A6

AmsterdamUtrecht

A13

A9A7

Waddenzee

Noordwijk

Delft

Elevation in

m+ MSL

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Climate change predictions:

Sea-level rise

Increase in river flow

Increase in winter precipitation

Higher risk of coastal flooding

Netherlands

=

‘sink’ of the Rhine Basin

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Peak discharge:Now: 16 000 m3/s

2100: 18 000 – 20 000m3/s

River Rhine: Peak discharge

15-25%increase

water level:

3m above MSL

↙ soil surface: 6m below MSL

Water head = 9 metres

Subsidence in combination with increased river flows

require higher river dikes

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Space for the river: creation of additional

storage capacity

River Rhine

Additional

storage

Flooding Risk in Dutch polder landscape

Flood-prone, heavily urbanised area, valuable in terms of‐ human settlements‐ industry‐ agriculture‐ ecology

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Increased risk of flooding/inundation

Risk-assessment maps on internet

For each province risk-assessment maps

can be consulted on the internet

Risk-

assessment

maps can be

consulted on

the internet

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Risk-assessment: public awareness

Public awareness is

difficult because risks

are small:

People do not follow-

up Government

instructions/advice

Climate change predictions:

Sea-level rise

Increase in river flow

Increase in winter precipitation

Higher risk of coastal flooding

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Change in rainfall: controlled Drainage

Rainfall:

↑ increase in winter

↓ decrease in summercontrolled

drainage

New paradigm: three step approach in drainage

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Controlled Drainage to reduce N Loading

Climate change predictions:

Sea-level rise

Increase in river flow

Increase in winter precipitation

Higher risk of coastal flooding

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Damage caused by flooding and subsidence

Flooding in residential areasRoads damaged by

uneven subsidence

Water mains and sewers damaged

by uneven subsidence

Smart solutions

Floating housesLiving with water

Floating greenhouses

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Consequences: development and O&M costs

will increase

0

50

100

150

200

(i) clay (ii) peat (iii) peat & water (iv) peat & sand

mill

ion e

uro

sInvestment costs O & M

Adaptation for 3 prevailing Soil Types:

ClaySandy soilsPeatLoam

3 Soil Types:• Peatlands• Reclaimed

clay soils• High sandy

4 Types of Land Use:

• Urban• Agriculture• Nature• Recreation

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Climate change: can we adopt ourselves?

Adapting to climate change: Examples from the Netherlands

Thank you for your attention

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