The water quality in Lake Saimaa, located next to the Imatra Mill, has improved over the years. The algae level in the wastewater catchment area shows that the lake is good condition. There are several reasons for this improvement. The amount of organic compounds arising from production has been reduced and the nutrients used in the treatment of wastewater have been optimised.
“We have been able to considerably reduce the amount of phosphorus and the organic chlorine compounds from pulp bleaching in the wastewater. This is appreciated by our customers and is one of the criteria for the EU Ecolabel,” says Teemu Klemetti, Environmental Engineer at Imatra Mill. Imatra Mill’ board and pulp production processes generate about two cubic metres of water per second.
The mills’ wastewater is treated biologically and chemically, and the treated water is fed back into Lake Saimaa. The South Karelian Fisheries Centre monitors the water, and the results are promising. The focus is especially on species that benefit from clean waters, such as vendace and whitefish. Research is conducted three times a year through test trawling and other methods.
“We have seen the biggest vendace catches reported since the year 2000, which indicates that the mills’ environmental impact on the water and fish has decreased compared to what it used to be,” says Aarno Karels, Managing Director of the South Karelian Fisheries Centre.
Furthermore, according to a water quality study conducted by the Centre for Economic Development, Transport and the Environment in the autumn 2013, the waters by Imatra Mill are of a good quality.