It is the five governors in Västmanland, Södermanland, Uppsala, Stockholm and Örebro counties who have written a letter on the matter to the Ministry of the Environment.
Governors see risks when climate change is expected to raise sea levels.
They point out in the letter that the height difference between Hjälmaren and Mälaren is only 0.7 meters, and it means that they will decrease further when climate change causes the Baltic Sea to rise.
They see a danger of floods as the possibility of draining is limited.
- It is high time to map the vulnerabilities and take measures to secure drinking water supply, food production and socially important infrastructure, protect buildings, and valuable water and natural environments.
Without these measures, there is a risk that this expansive region cannot continue to be one of Sweden's most important growth engines, the governors write in the letter.
The letter refers to several reports that address the risks in the area of a changing climate.