Climate, nature and biodiversity
For centuries, Amsterdam was notorious for the filthy water in its canals. This did not change until the Oranjesluizen sluices and the Zeeburg pumping station were built in the nineteenth century. The water quality has further improved in the last few decades, and the city council works with various governmental bodies to ensure that it stays clean.
Photo: Frans Ruiter
Biodiversity
Partly as a result, Amsterdam and its canals now enjoy surprisingly rich biodiversity. This is not just because of the clean water. Other contributing factors include the combination of fresh and salt water, and the fact that the region is part of an important migratory route for fish. This combination of circumstances means that the IJ is home to fish such as flounder, seabass, sea trout, cod, and plaice. Species found in the fresher parts of the IJ and in the canals include catfish, carp, pike, pikeperch, and eel. In total, the canals, harbours and IJ contain some sixty-five species of marine and freshwater fish.
The canal water also attracts many birds, which use the city as a feeding area. Among the more recent arrivals are the great crested grebe and the common coot, which eat fish, plants, and mussels, suggesting that the water provides an adequate supply of food. The canals are kept clean by Waternet, the water grid manager, which fishes out floating waste on a daily basis and cleans the canal area several times a year.
Climate change
Plants and trees are flourishing too. Many different species grow along the city’s one hundred kilometres of canals and wharves, and in 2017 it had 270,000 trees, about one for every three inhabitants. These are important not only for the cityscape, but also in mitigating climate change by vaporising large quantities of water, which has a cooling effect.
In recent decades, Amsterdam has seen the results of climate change. If sea levels rise, so will the water in the canals, in which case the city and the surrounding region will be dependent on pumping stations. If the water in the IJ becomes too high, the sluices between it and the city will be closed and the Zeeburg pumping station will remove the excess. Climate change will mean that Amsterdam needs additional pumping capacity, including a new station to transport more water to the IJmeer.
Another consequence of climate change is subsidence affecting old buildings in the inner city. Long periods of drought cause the groundwater level to fall, drying out the wooden piles beneath the buildings and leading to their disintegration.
Bron: Amsterdam city council