PROTE-fos – comprehensive service of lakes reclamation
PROTE offers a comprehensive service of reclamation of lakes which are hypereutrophic with severe algal blooms. The core of our service is chemical blocking of phosphorus directly in lake’s (reservoir’s) bottom agitation controlled and artificially triggered agitation of these sediments. Additionally, chemical blocking of phosphorus is supported by individually chosen supplementary methods, for example immersing barley straw, growing macrophytes and macroalgae, regulating fish stock, dredging particular areas of bottom, etc.
As the only company in Poland we have carried out a comprehensive project of reclamation of two lakes in Gniezno (Lake Jelonek and Lake Winiary), which was financed by Life+ program (European Union financial instrument supporting innovative undertakings).
The source of the problem
Many lakes which used to be clean now have scarce esthetical, recreational and utility values, and the constantly growing demand for drinking water makes us treat every water reservoir as a potential source of drinking water. Algal blooms as the most frequent effect of lakes eutrophication are becoming more and more significant medical problem, although until recently they were considered only an esthetical shortcoming. Blue-green algae dominating in degraded water reservoirs produce toxins which are harmful to health. Lakes reclamation is a domain in which we deal with an ecosystem, and our main objective is to heal the ecological situation. It involves halting or reversing the process of growing fertility of reservoirs. Measurable effect of successful reclamation works is the elimination of blue-green algae blooms and consequently improvement of water quality (improved transparency).
Examples of toxic influence of blue green algae on humans and animals, described in world literature.
An analysis of the situation of almost 1250 lakes and reservoirs in Poland have shown that approximately 30% of them are degraded reservoirs, requiring remedial actions, an example of which is reclamation. Another 30% of reservoirs are at risk of degradation [Soszka, H. 2010. Założenia projektu dotyczącego ograniczeń w korzystaniu z wód jezior i użytkowaniu ich zlewni. Mat. konf. „Ochrona i rekultywacjajezior” (Ideas of the project concerning limitations in using lake water and lake’s drainage basin. Materials from conference "Lakes protection and reclamation”), Toruń, 2010].
The process of growing fertility of water reservoirs (eutrophication) is caused by human factor. Increased quantity of biogenes in a reservoir as a result of direct inflow of pollutants (communal and industrial sewage), intensive fertilization of fields around the reservoir, increased erosion in the drainage basin, influence of water birds (excrements, feeding), and anglers’ activity are the causes of negative changes in lakes, such as:
- massive development of algae, especially the blue-green algae (blooms),
- worsened transparency of water,
- gradual decline of macrophyte species, growing at the bottom of reservoirs,
- decreases in the variety of fauna and flora,
- oxygen depletion in bottom waters.