Salinisation of the land in time

The past

In the distant past barely any humans permanently lived in delta areas, mostly due to the hunter-gatherer’s nomadic lifestyles. This slowly changed as they began to grow their food and spend more time in once place.

Legend

Salt water

Fresh water

Brackish water

Salinisation of the land in time

The present

Today deltas are increasingly populated. This is due to the economic advantages, good soil for agriculture and sufficient water, water management, and because we are equipped to handle the threats posed by flooding.

Long-term effects

Less and more expensive drinkwater

Changes in forms of agriculture

Migration

Moving of industry

Health effects

Legend

Salt water

Fresh water

Brackish water

Salinisation of the land in time

The future

Salinisation forces people to move

Coastal reotion

Drowned islands

Overtopping of sea water

Freshwater lenses shrink

More land subsidience

Increase of fresh water shortages

In order to safeguard our current standard of living and safety, we must adapt to the new situation.


Will we be able to make the change in time?

With adaptations

Legend

Salt water

Fresh water

Brackish water

Salinisation of the land in time

The future

In order to safeguard our current standard of living and safety, we must adapt to the new situation.


Will we be able to make the change in time?

With adaptations

Legend

Salt water

Fresh water

Brackish water

And it happens globally...

How much fresh groundwater will decrease due to sea-level rise compared to present conditions,

More than 35 million people could lose more than 10% of their fresh groundwater resources by 2100, compared to 2020, according to RCP 8.5 sea level rise scenario.

Some major countries where saltwater intrusion into coastal groundwater systems is taking place


Italy, Spain, USA, Brazil, Morocco, Egypt, Tanzania, Australia, China, Bangladesh, India, Israel, Iran, Indonesia, Belgium, the Netherlands, Denmark, Turkey, Colombia, Ghana, Germany and Senegal.

Facts and figures

Essential basic necessities

50%

of our drinking water is fresh groundwater

38%

of irrigable area is irrigated with fresh groundwater

Pressures on the coast

Population density is significantly higher in coastal areas

One third

of the world population lives in coastal areas (<70km) being 2.65 billion

Ongoing trend of coastal migration

This is associated with global demographic changes. Most of the world megacities are also situated at the coast

Groundwater salinisation does not just occur in coastal areas

Total global land area negatively affected by salinity

5x

the size of France

= 277 million ha

Coastal defence

Prevent the seawater to overflow the coastline or overtop the coastal defence

Rainwater harvesting

With improved understanding of the subsurface you can store excess (rain)water underground and use it during dryer times.

Gebruik en verspil minder zoet

Gebruik geen zoet water als het niet nodig is, gebruik brak of zout water in zwembaden of om het toilet door te spoelen.

Brackish water as fresh water resource

In the coastal zone, fresh ground-water 'floats' on heavier saline groundwater with a brackish transition zone. This brackish water is easier to desalinate (and cheaper too).

Salt-resistant crops

Some crops grow better (and even taste better too) if there is brackish groundwater in the soil

Desalinise with new technologies

Desalinization techniques are getting cleaner and energy efficient. Desalinization is a key asset in the coastal zone.

Waste water (re)usage & circulation of water flows

Use recycled (waste) water to fluish your toilet and car washing. Don't make fresh water go to waste.

Changing your water usage mindset

Utilities can be changed but consumers also need to be aware of spillage and consumption. How much fresh water is used to produce certain crops, meat or clothes?

Aquifer storage and recovery

Refill the aquifers that are used for irrigation whenever there is a surplus of fresh rain in the wet season, or 

Water pricing

Once water is priced, water use will drop over a short time

Driver

Sealing subsurface and shortage of fresh water

Effect

  • Less groundwater recharge infiltrates into the subsurface

  • No replenishment of the fresh groundwater resources

Driver

Sea level rise and land subsidence

Effect

  • Shifting of saline/fresh interface further inland

  • Coastal freshwater resources are reduced

  • Overtopping of near shore areas

  • Lower elevation levels, so saltwater overtopping can reach further inland

Driver

Overextraction and water mismanagement practices

Effect

  • Upward flow of saline groundwater

  • Lower sediment inflow, so deepening of river beds and more saltwater intrusion of surface water

  • Upstream less fresh surface water availability

  • Lower freshwater recharges through rivers, so less freshwater availability from surface water

Driver

Storms, hurricanes, typhoons and cyclones

Effect

  • Seawater overtopping and infiltration into the subsurface leading to salinisation of fresh groundwater resources

Salinisation of the land in time

The past

In the distant past barely any humans permanently lived in delta areas, mostly due to the hunter-gatherer’s nomadic lifestyles. This slowly changed as they began to grow their food and spend more time in once place.

Salinisation of the land in time

The present

Today deltas are increasingly populated. This is due to the economic advantages, good soil for agriculture and sufficient water, water management, and because we are equipped to handle the threats posed by flooding.

Salinisation of the land in time

The future

In order to safeguard our current standard of living and safety, we must adapt to the new situation.


Will we be able to make the change in time?

Option 1: Without adaptation

Option 2: With adaptations