Golden algae have bloomed in the Dzierżno Duże reservoir on the Kłodnica River. Hydrogen peroxide is being released into the water to reduce its population and slow down its entry into the Oder. – The situation at the Dzierżno reservoir remains difficult – admitted on Sunday the Minister of Climate and Environment, Paulina Hennig-Kloska.
High concentrations of golden algae were recorded in Dzierżno Duży, as well as section IV of the Gliwice Canal, which is a corridor for the Kłodnica River, at the beginning of August. The Provincial Crisis Management Center in Katowice reported that over 105 tons of dead fish have been caught from there so far.
Dead fish in the tankPAP/Jarek Praszkiewicz
“The situation is dynamic”
Hydrogen peroxide (hydrogen peroxide) is added to the water containing golden algae (Prymnesium parvum), which in appropriate doses limits the blooming of toxic organisms.
– The situation at the Dzierżno reservoir remains difficult, although it seems to be stabilizing. We must remember that we are dealing with unfavorable meteorological and hydrological conditions. All this makes the situation dynamic – it changes from day to day – informed the head of the Ministry of the Environment during a conference held near the operation conducted by the services.
As she said, the actions taken are intended to protect the Odra from a disaster such as that which occurred in 2022.
– What we have been doing here for many days is to limit the disaster that is taking place on the Dzierżno reservoir, so that it does not (the golden algae – ed.) take over the Gliwice Canal, and above all the Oder, so that we do not have a repeat of 2022. If I were to assess the situation from this perspective, we have it relatively under control. The situation with the golden algae is not spreading to areas other than Dzierżno – she assured the minister.
Swimming is prohibited in the river, among other places.PAP/Jarek Praszkiewicz
Experimental method
Hennig-Kloska noted that the effective fight against the golden algae is the result of an experiment conducted by the Institute of Environmental Protection and scientists who work on site. As the Minister of the Environment added, the use of the new method allows for the reduction of the golden algae by 95 percent, and at night even by 99 percent.
Hydrogen peroxide was released into the tankPAP/Jarek Praszkiewicz
This caused less of it to enter the Oder, of which the Kłodnica is a tributary. In the river, there is no possibility of stopping the golden algae using a system of locks, as is the case with the Gliwice Canal.
Hydrogen peroxide is used to combat blue-green algae, neutralize sewage, and purify water, among other things. It has been used to combat golden algae blooms in lakes in the UK.
“The advantage of hydrogen peroxide is that it decomposes in water into oxygen and water, leaving no by-products that could accumulate in the environment. Hence, it is used experimentally in various water conditions, including lakes,” informed the Ministry of Climate and Environment.
Hydrogen peroxide was released into the tankPAP/Jarek Praszkiewicz
In Poland, this method was tested in laboratory and field conditions in 2023. Using 40 milligrams of H2O2 per liter of water resulted in a 97% decrease in the golden algae population.
Limit brine from mines
As Hennig-Kloska added, her ministry is working on finding a way to reduce the amount of pollution that flows into reservoirs such as Dzierżno and the Oder itself. This primarily concerns brine discharged into waters from mines.
– An inter-ministerial team is working on this. I believe that by the end of the year, we will be able to present an investment plan so that we can fight the causes of the problem, not just the effects – she concluded.
Main image source: PAP/Jarek Praszkiewicz