Helsinki continues to reduce the city’s nutrient loading on the Baltic Sea from its wastewater treatment plants, which recorded significant improvements in 2011. The reduction in nutrient loading on the sea complies with the city’s commitment to protect the Baltic Sea, as spelled out in the Baltic Sea Challenge campaign to save the sea.
Wastewater treatment fulfilled tight in-house goals
Wastewater treatment in the Helsinki region in 2011 met the in-house goals set for phosphorous and nitrogen removal, achieving lower emission levels than those prescribed in the license conditions. Overall, the treatment operations met their license conditions in every quarter of 2011 in terms of both emission limits and treatment efficiencies.
Municipal wastewater treatment in the region is handled by HSY, Helsinki Region Environmental Services Authority, at plants in Viikinmäki, Helsinki, and Suomenoja, Espoo. Together these plants treat the wastewaters of more than one million people. In 2011 they received and treated a total of 139 million cubic metres of wastewater.
HSY reduced the phosphorous loading on the sea by nearly 22 percent from 2010, emitting a total of 31 tonnes in 2011. The reduction in the nitrogen loading was nearly 10 percent, to a total of 1,043 tonnes. Both treatment plants discharge their treated wastewaters into the Baltic Sea, so reductions in emissions contribute significantly to the protection of the Baltic Sea by HSY.
Phosphorous and nitrogen, when present in water in excess amounts, are nutrient pollutants that cause eutrophication - overgrowth of algae - which harms water quality, food resources and habitats, as well as decreasing the oxygen that fish and other aquatic life need to survive.
Viikinmäki – one of Finland’s foremost environmental achievements
The main wastewater treatment plant of HSY is the Viikinmäki plant, which treats the wastewaters of about 800,000 people in a 15-hectare underground facility built into the Helsinki bedrock. Viikinmäki, opened in 1994, still stands as one of Finland’s main environmental investments.
Baltic Sea Challenge
The Cities of Helsinki and Turku, Finland, launched a campaign to improve the state of the Baltic Sea – the Baltic Sea Challenge – in 2007 and challenged other players to join. The cities drafted an action plan comprising their commitments to the goal. The plan is also meant to set examples for other players to draft their own plans.
Helsinki’s and Turku’s commitments comprise 8 actions including: reducing point loading by improving wastewater treatment (Helsinki’s reductions in nutrient emissions from wastewater treatment is an example of this); reducing diffuse loading such as loading from city-owned farms and emissions from scattered settlements; and reducing wastewater discharges from shipping and boating.
In 2012, there are already more than 170 municipalities, institutions, corporations and other types of organizations all around the Baltic Sea region that have accepted the challenge and joined the campaign. The newest participant is the municipality of Kuldiga, Latvia, since 16 May 2012.
Baltic Sea Challenge