97.5% of all water on Earth is salty. Unfortunately, it is becoming increasingly common for salt water to cause problems on land.

Brackish seepage water
This salinisation can occur in groundwater, surface water or on land due to, among other things, sea level rise in combination with soil and groundwater decline, which disrupts the balance between salt and fresh water. The pressure of it 
salt water expands while the counter pressure of the fresh water decreases. This makes it easier for brackish seepage water to reach the surface, resulting in salinisation.

Irrigation, drinking water and infrastructure
The inflow of seawater into our waterways due to reduced rainwater discharge also has a direct effect on drinking water extraction and irrigation of agricultural areas.

When sprinkled with salt or brackish water, salt remains behind after evaporation. In addition, deep - often fossil - groundwater is often rich in minerals that remain on the land after irrigation. Which also results in salinisation.

Furthermore, infrastructure projects can cause permanent disruptions to existing bubbles of fresh and salt groundwater.
It is therefore important for agriculture, construction works, drinking water extraction and for nature in general that the degree of salinisation and the seasonal and weather influences are properly mapped out.

Salty-sweet gradient
The relationship between water level and salinisation is important, partly because salt and fresh water are difficult to mix. That is why it is often important to measure at different depths to see the salt/fresh gradient.