The research was carried out on Karczemne Lake, a water reservoir located in Kartuzy (northern Poland, Pomeranian Lake District). Monitoring of the water and bottom sediment of Karczemne Lake showed a very high level of contamination of the reservoir by a long-term inflow of untreated municipal sewage. The trophic status index of total phosphorus (TP) was unusually high at 101, and the TP content in the bottom sediments—31 mg g⁻¹ (dry weight)—was the highest value recorded worldwide in a lake. Based on the monitoring results, to achieve constant improvement of the water quality, we recommend a completely new, safe and economically justified method of bottom sediment removal and management. A very important aspect of this method is the prevention of uncontrolled sewage discharge back into the lake basin. Removed sediment with interstitial water will be pumped through a pipeline and transported to a sewage treatment plant. In the sediment mining field in which the sludge will be removed, the first phase of phosphorus inactivation will be carried out to chemically precipitate pollutants distributed in the water column as a result of sediment resuspension. After the deepening of the entire lake basin, the method of phosphorus inactivation will be carried out on the entire surface of the lake as the next stage of restoration. A supporting activity will be biomanipulation. Before the restoration is started, the municipal sewerage system will be modernized.

中文翻译：

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是否有可能恢复被严重污染的浅层城市湖泊？

该研究是在Karczemne湖上进行的，Karczemne湖是位于Kartuzy（波兰北部，Pomeranian湖区）的水库。监测Karczemne湖的水和底部沉积物表明，未经处理的城市污水的长期流入会严重污染水库。总磷（TP）的营养状态指数异常高，为101，底部沉积物中的TP含量为31 mg g ^-1（干重）—是全世界湖泊中记录的最高价值。根据监测结果，为不断改善水质，我们建议采用全新，安全且经济合理的底部沉积物去除和管理方法。该方法的一个非常重要的方面是防止不受控制的污水排放回到湖盆。去除的含间隙水的沉积物将通过管道泵送并输送到污水处理厂。在将清除污泥的沉积物采矿场中，将进行磷失活的第一阶段，以化学方式沉淀由于沉积物重悬而分布在水柱中的污染物。整个湖盆深化之后，磷的灭活方法将在整个湖面进行，作为恢复的下一阶段。支持活动将是生物操纵。在恢复工作开始之前，市政污水处理系统将进行现代化改造。