Nova članica Žmergovog tima, volonterka EVS-a iz Francuske po imenu Helene, izrazila je želju posjetiti postrojenje za pročišćavanje vode u Ičićima i saznati sve o menadžmentu vodnim resursima u Opatiji.
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How is our sewage cleaned?
by Helene Lahaye
Upon the arrival to Opatija, Croatia, my first interest as a graduate in aquatic systems and water management was the water management system of the town. A tour was scheduled with the local water supplier, Komunalac in Ičići. My observation is the following.
Did you ever wonder: what does the water I used become?
Years ago, sewage went directly in the sea through a pipe and contaminated the entire ecosystem. However after it has been used, the water needs to be cleaned before it returns into the natural environment to avoid polluting.
In Ičiči in 2012, a water treatment plant has been built to respond to the European norms and to preserve the sea. This plant permits treatment of the sewage for Lovran and Opatija. It collects the water of the cities by canalization but also the water of the septic tank. This plant can treat up to 1500 m3 per day during the winter and until 3500 m3 per day in the summer.
Let’s see how this process works.
First the sewage is stocked in a big pool, from which when is almost full, a pump sends the water to the mechanical preliminary treatment. This step involves separation of solid wastes, grease and sand. A fence stops the solid waste, the sand goes down the tank driven by gravity and the grease goes up thanks to the air added to the water.
Then, the water continues its way throughout a metallic filter. On one hand, we have sludge that is solidified by chemical process and dried before it goes to the landfill. And on the other hand, we have clean water that can go back in the natural environment; the sea. To be sure in the quality of the water at the end, each hour several tests are done by a technician.
In the sewage we have bacteria that produce’s some gases like methane and sulfur dioxide. These gases are toxic and really stinky; this is why the plant is equipped with air filtration system. Thanks to that the bad odor around the plant is minimized.
So, your water is treated physically which mean that only solid and big waste are removed. Soon Komunalac will build other process, biological and chemical. This way, the invisible pollution like residues of organic matter will be removed. The water will be treated completely and the impacts on the sea should be the smallest possible.
