The water quality in the port area is relatively good.
- There is more oxygen in the water in the docks, although the Chemical Oxygen Demand (COD) does sometimes exceed the water quality norm.
- The water’s saline levels also comply with the standard, but they have increased slightly, because of longer dry spells.
- A large share of the nutrients, such as phosphates and nitrogen, are supplied via the aboveground watercourses, although this is far from sufficient.
Invertebrates that are visible to the naked eye and live in water are still not thriving although various efforts have been undertaken to improve the ecological and chemical condition of the water and the sediment.
Various efforts to improve the ecological infrastructure in the docks have paid off. Eighteen fish species were found in the spawning ground near Canal Dock 18, including perch, common roach, rudd, silver bream, big-scale sand smelt, sea bass and even the invasive round goby. We also created shelters in the water and the dock walls where water creatures and fish can take shelter.
Levels for most of the substances that are listed in the European Water Framework Directives do not exceed the norm, according to water analyses. Until 2015, the number of substances that exceeded the norm was limited. Since 2016, water quality norms have been tightened and some levels now exceed the norm as a result. We are continually investigation the cause of this.
We discovered among others that the problem of polyaromatic hydrocarbons is entirely due to atmospheric deposition. Our priority is to reduce the substances of which the source of emission is located in the port.
The sediment is also tested. In recent years, the number of contaminations has dropped as the dredging activities and oil spill remediation are handled differently. But there is still plenty of margin for improvement.
Companies can actively help improve water and sediment quality by:
• purifying household waste water.
• avoiding diffuse discharges.
• installing valves in the drainage system in case something does go wrong.
• optimise water consumption.
Environmental permits often require companies to pay attention to water quality.