Higher and more variable groundwater levels result in most substances – including toxic substances – being carried along with flowing water to a greater extent and thus spreading further.
When the sea level rises, polluted areas along the coast may become flooded or suffer from erosion. Changed water conditions in the ground may increase the danger of landslides and mudslides, with soil moving from polluted areas. The pollutants can then be spread across larger areas.
Higher water flows
Higher water flows mean that larger quantities of dissolved and particulate pollutants penetrate the ground and are transported via surface runoff drains, surface water or groundwater into watercourses, lakes and seas. Higher water flows can also result in old and new industrial areas and sewage treatment plants being inundated. This leads to ‘pollution shocks’ that may have an impact on human, plant and animal life. Areas in which precipitation volumes, groundwater levels and flow rates are expected to decrease may also be affected through changes to the chemical properties of the ground.
Higher average temperatures also tend to increase the mobility of pollutants, for example because the length of time when there is ground frost becomes shorter.