Pollution which resulted from effluent from a local silage farm flowing into Jõgeva County river is receding, the Environmental Board (Keskkonnaamet) says, though not before causing the death of thousands of fish.
Dora Kukk, of the Environmental Board's Jõgeva supervisory office, said the authority is continuing to investigate source of the incident, which has affected the Umbusi river, and will take measures to prevent any further pollution.
She said: "We plan to thoroughly review the collection wells and run-off system connected to the silos which caused the pollution and ascertain how such a situation could have arisen in the first place."
The board is also constantly monitoring the state of the river water, in conjunction with the local government in the nearby town of Põltsamaa, and the Health Board (Terviseamet).
Kukk said: "We agreed with Põltsamaa municipality that the it will continue to monitor water quality. This is important in order to see how quickly the situation resumes normality. We certainly do not recommend swimming in the river and the Lustivere dam in the meantime, until we have received confirmation that the water in the river is completely safe to do so."
The Environmental Board, along with local volunteers has recovered over 4,000 dead fish from the river so far, including close to 1,300 brown trout and around 40 crayfish, though, while more dead aquatic life finds are inevitable, the peak has been reached.
"The water in the river is odorless and clear up to the Lustivere dam, and no pollution has been detected downstream from the village of Umbusi," Kukk said.
The company allegedly responsible for the spillage, AS Pajus ABF, is already subject to misdemeanor proceedings, Kukk added, with the exact damage caused and ensuing fine still to be ascertained.
The board determined on Sunday that silage effluent from an AS Pajus ASB farm had leaked into storm drains as a result of blocked storage guttering. The pollution reached the Umbusi river via the storm drain system.
The pollution was localized and its spread halted as of around 7 p.m. on Sunday.
Water samples will be taken every few weeks, rather than every few days; weekly checks are the right timescale to allow pollution levels to fall, the board says.
The 45-km long Umbusi river is a tributary of the Pedja, which in turn flows into the Emajõgi.
Editor: Andrew Whyte