Stopnie wodne na Odrze i ich potencjalny wpływ na wody podziemne
Abstract
The Odra barrages and their potential influence on groundwater.
A b s t r a c t. Hydraulic constructions have a significant impact on the surface water regime, and on the soil and groundwater conditions of the entire adjacent valley. Above the water barrages, surface water is being accumulated and the river changes its character to infiltrating. Below the barrages, there is deep erosion of the riverbed, the surface water level and the groundwater drainage base decrease, which results in the lowering of the groundwater level in the adjacent river valley. The examples of such phenomena are barrages on the Odra River downstream Wrocław. After the construction of barrages in Rędzin, Brzeg Dolny and, recently, in Malczyce, a process of intensive deep erosion of the Odra riverbed is observed, currently along the section from Malczyce to Ścinawa. It ranges from 0.8 m in Ścinawa to 2 m in Malczyce. This results in a lowering of the groundwater level of the first aquifer on the discussed section of the Odra Valley. This phenomenon has a particularly negative impact on the Łęgi Odrzańskie area conditions that are closely dependent on the groundwater level. The greatest damage occurs in oak-elm-ash riparian forests and concerns the oldest oaks. Łęgi Odrzańskie is a valuable ecosystem with numerous protected species that have been legally protected under the Natura 2000 network and national forms of nature protection and protected landscape areas. The designed barrages in Lubiąż and Ścinawa will stop the progressive deep erosion of the Odra riverbed. They will contribute to raising and stabilizing the groundwater level in the Odra Valley, which will partly return to a nearly natural level.
A b s t r a c t. Hydraulic constructions have a significant impact on the surface water regime, and on the soil and groundwater conditions of the entire adjacent valley. Above the water barrages, surface water is being accumulated and the river changes its character to infiltrating. Below the barrages, there is deep erosion of the riverbed, the surface water level and the groundwater drainage base decrease, which results in the lowering of the groundwater level in the adjacent river valley. The examples of such phenomena are barrages on the Odra River downstream Wrocław. After the construction of barrages in Rędzin, Brzeg Dolny and, recently, in Malczyce, a process of intensive deep erosion of the Odra riverbed is observed, currently along the section from Malczyce to Ścinawa. It ranges from 0.8 m in Ścinawa to 2 m in Malczyce. This results in a lowering of the groundwater level of the first aquifer on the discussed section of the Odra Valley. This phenomenon has a particularly negative impact on the Łęgi Odrzańskie area conditions that are closely dependent on the groundwater level. The greatest damage occurs in oak-elm-ash riparian forests and concerns the oldest oaks. Łęgi Odrzańskie is a valuable ecosystem with numerous protected species that have been legally protected under the Natura 2000 network and national forms of nature protection and protected landscape areas. The designed barrages in Lubiąż and Ścinawa will stop the progressive deep erosion of the Odra riverbed. They will contribute to raising and stabilizing the groundwater level in the Odra Valley, which will partly return to a nearly natural level.