For a long time, boat owners have been painting their boats to prevent barnacles, algae and mussels from growing on the bottom. The problem is that many antifouling paints can be toxic. Toxins affect animal and plant life in Lake Mälaren and cause a direct problem for us humans as the lake provides us with drinking water. In years gone by, it was common for antifouling paints to contain organic tin compounds, TBT, which are endocrine-disrupting chemicals. This toxic substance has been banned since 1989, but we are still measuring high TBT levels, especially in marinas.
Washing the fouling off the bottom of the boat is a sustainable alternative to using toxic paints. Following requests from local boat owners and boat clubs, there is now a boat bottom wash at Kraftverkshamnen in Västerås. This boat bottom wash makes sustainable boating possible. The goal is for all pleasure boats in the municipality’s harbours to have non-toxic bottoms within a few years.