The residual pollution in the Karosta canal has been studied – swimming and fishing there are not recommended / Article

IN SHORT:

• Due to the pollution of the Soviet times, the Karosta channel is on the list of hot spots of polluted places in the Baltic Sea.
• An investigation has now concluded to identify the risks and methods to mitigate the remaining contamination.
• Already last year, approximately half of the canal’s 72ha water area was cleaned.
• However, the Norwegian aid of 4 million euros was not enough to clean the entire canal.
• Additional funding for canal cleaning has not yet been found in any fund.
• The remaining pollution comes from shipping lanes.
• Scientists admit that within 10 years oil products will be degraded by microorganisms.
• The impact of the canal on the health of the population has been evaluated – if you don’t eat fish from it and don’t swim, there are no risks.

Due to the pollution caused during the Soviet years, the channel is included in the list of hot spots of polluted places in the Baltic Sea, and it has not yet been possible to leave it, even after last year’s rehabilitation works.

An investigation of the canal by Norwegian researchers to identify existing risks and methods to mitigate remaining pollution concluded this week.

The Norwegian Water Research Institute has developed a methodology for the study of polluted water bodies connected to the Baltic Sea and for the assessment of environmental risks. Water and soil samples were also taken in the Karosta canal, comparing the results before and after the historical pollution was exhausted.

“We checked several places in the canal that might require more attention in the future, but the exhausted places have become much cleaner,” said Jarle Havardstun, an engineer at the Norwegian Water Research Institute.

During the Soviet years, various oil products, mercury and several other environmentally harmful substances entered the waters of the Karosta Canal.

Bulky waste was picked up a few years ago, while last year about half of the canal’s 72-hectare water area was drained of contaminated sediment and soil.

“It was the one that went out into the Baltic Sea at some currents. Currently, the Karosta channel has been cleaned in several stages. In the last pass, 145 thousand cubic meters of contaminated soil has been exhausted, stored behind the groove wall – in the place of deposit,” said the manager of the Liepāja Special Economic Zone, Uldis Hmieļevskis

The approximately 4 million euros allocated by the Norwegian financial instrument was not enough to exhaust the pollution from the entire channel, additional funding for such a purpose has not yet been found in any fund, so we have to think about what to do with the remaining part of the pollution.

It lies away from active shipping lanes, so it cannot be stirred up by ship propellers, and according to scientists, there is a possibility that within the next 10 years, oil products will be naturally degraded by benthos, or living microorganisms, in the channel.

“If this situation has fundamentally improved, then perhaps with small additional excavation works in the territories where economic activity is planned, we could say that we are removed from this list of “Helcom” hotspots,” said Ivo Kolinņš, project manager of the Liepāja SEZ administration.

Together with Norwegian scientists, for the first time in the history of the Karosta Canal, an assessment of its impact on the surrounding environment and residents was also carried out.

“This pollution cannot have a negative impact on the health and quality of life of the city’s inhabitants, except for the cases when the inhabitants consume fish caught from the Karosta canal, which could contain potential contamination, do not use the water for drinking, and do not swim,” explained Ivo Koliņš.

EU directives provide that the Karosta channel should achieve environmental quality appropriate for the port water area by 2035. The Liepāja SEZ administration expresses confidence that it will succeed.