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The aim of the study was to present the concepts of water reclamation and development of post-mining areas of the Adamów Lignite Mine following the termination of its excavating operation. Reclamation procedures will accelerate the process of restoring the devastated post-mining area to the natural environment and, above all, will contribute to the increase in local water resources. It was decided to create several water reservoirs with different surface areas and capacities within the final workings of opencasts. The reservoirs are used for water retention, recreation, melioration and flood control purposes, as well as for depositing overburden from other opencast workings. In total, the construction of 5 water reservoirs will include 4 weirs, 7 monks and 3 culverts with damming as well as a number of kilometres of inflow and outflow channels. The schedule of works and expenditures of the investment amounts to PLN 14.509.512 and is divided into 5 stages, not only covering the construction of the reservoirs, but also the water and drainage infrastructure necessary for their proper operation. All constructed and planned water reservoirs (Przykona, Janiszew, Koźmin, Głowy, Adamów, Koźmin Końcowy and Władysławów) will become new permanent elements of the landscape and the hydrographic network, coupled with the catchment system of the Warta River. They will allow for increase in the retention capacity of the Adamów Lignite Mine's area from previous 32,3 million m3 to 219.6 million m3 in the perspective of 2023. They will improve the microclimate of post-mining areas and have a positive impact on lands created as a result of reclamation. They will provide retention for irrigation of adjacent agricultural areas and help reduce economic and natural losses caused by flooding. They will open recreational opportunities for residents of surrounding areas characterised by water shortages. The post-mining reservoirs, formed during mining operations, perfectly fit into the Small Retention Program. The existing and planned water bodies are the best proof for the rightness of decisions taken in the field of reclamation for water purposes. Landscape shaping during the exploitation of lignite, as practice shows, is a great opportunity for the post-mining region to create reservoirs in places where they do not occur in nature.

The paper presents the results of the researches carried out in 2000-2009 period in pond No. 1 catchment. The pond is located at Siemianice Experimental Forest Farm in Wielisławice forest district. This area is situated at South Wielkopolska Lowland and constitutes its southern frontier. In terms of hydrography, the object is a part of Niesób River catchment area, which is a left-bank tributary of the Prosna River. The catchment area is about 7.5 ha and the forestation is 100%. Fresh mixed broadleaved forest is the dominant area of the catchment. Fresh mixed coniferous forest stands also have a significant share in the catchment area. Moist mixed broadleaved forest stands occupy the rest of the area neighboring the No. 1 pond. Albic Arenosols (FAO1988) consist of sand (USDA) are prevalent in the area. The area of the mid-forest pond No. 1 covers about 0.13 ha. The average depth of the postglacial pond is approximately 1.0 m. It is worth noting that the average and dry years dominated in the analyzed period. The researches indicated that the groundwater level lowered by about 70 cm in this period. Retention decrease calculated for analyzed area was about 250 mm, considering the average soil porosity of about 36%.

The paper presents the results of the researches carried out in the catchments of pond No 1 and No 6. The ponds are located in Siemianice Experimental Farm, belonging to “Lasy Rychtalskie” Promotional Forest Complex, in Wielisławice (pond No 1) and Laski forestry (pond No 6). The researches were carried out in two hydrological years 2010/2011 and 2012/2013. The years had different precipitation. The area of catchment of pond No 1 is about 7.5 ha and its forestation totals 100%. Whereas catchment area of pond No 6 is about 37 ha. The forestation of this pond is about 40% and the rest are arable areas. The analyzed pond No 1 and 6, have mild scarps, and they are natural pond melting out. The area of pond No 1 is 0.13 ha, whereas pond No 6 is 0.35 ha, and averages depths of both ponds are 1.0 m and 1.4 m. The results confirmed a connection between water in ponds and groundwater in neighboring areas. In some periods water of ponds supply surrounding areas and in some periods on the contrary – groundwater supply water in ponds. Correlation coefficient (from 0.43 to 0.96) calculated for relation between water levels in ponds and groundwater were statistically significant for the level α=0.01 in analyzed hydrological years.

State of water-drainage infrastructure affects the conditions for sustainable development of rural areas. Irrigation-drainage systems for governing water relations in soils of the valley areas consist of a system of rivers, canals and ditches with impoundment structure. The considerable neglect in the maintenance of existing water-drainage infrastructure resulted in their recapitalization. The most important way to restore the efficiency of their proper functioning should be their correct and timely maintenance. The study evaluated the need for maintenance of basic drainage structures in the district of Stargard. The study covered the years 2010–2012.

The objective of the article was to present possible applications of recession flow curve in a small lowland watershed retention discharge size evaluation. The examined woodland micro catchment area of 0.52 sq km is located in Puszcza Zielonka in central Wielkopolska. The Hutka catchment is typically woody with high retention abilities. The catchment of the Hutka watercourse is forested in 89%, the other 11% is covered by swamps and wasteland. The predominant sites are fresh mixed coniferous forest (BMśw), fresh coniferous forest (Bśw) and alder carr forest (Ol). Landscape in catchment is characterized by a large number of interior depressions, filled partly with rainwater or peatbogs, with poorly developed natural drainage. The watercourses do not exceed 1 km in length, the mean width is approx. 0.5 m, while mean depth ranges from 0.2 to 0.3 m. During hydrological research conducted in 1997/1998–1999/2000, 35 major (characteristic) raised water stages were observed in Hutka after substantial precipitation. The recession curve dating from 18–24 September 2000 has the α and n rates nearest to average. Comparing the model curve and the curve created by observing watercourse flow, one can notice their resemblance and that they have similar ordinate values as well as shape. In the case of other recession curves, the maximum differences of ordinate values are also about 0.1–0.2 l/s/km2. The measuured α and n rates do not reveal any regularities. There are no significant statistical Horton model parameter (for recession flow curves) dependencies between α and n and e.g. initial flows (Qo) or the whole period of high water waves (Qp). Consequently, calculated relation between these parameters is only an approximation for the general evaluation of the retention discharge in the catchment area towards retention with flow function.

The paper presents the results of researches carried out in the middle part of Pizza Zielonka forest complex. The aim was the evaluation of retention changes at wetlands and mid-forest ponds. The object of the study was the catchment of the Trojanka watercourse, considering from the origin to the cross-section of Zielonka Lake. The catchment is located in in the central part of the Wielkopolska region, approximatelly 20 km on the North-East of Poznań. The area of this forestall catchment is about 223 ha. In the paper an analysis of the results from three hydrological years was presented. The results of the years 1987 (wet year), 2003 (dry year) and 2009 (medium year) were analysed against meteorological conditions. Retention capacity in each wetlands, as well as the possibility of water retention in the Trojanka watercourse was calculated. The researches confirmed significant meteorological conditions influence the amount of retentioned water. The calculated capacity of retentioned water was 15 852 m3 considering the total area of wetland and swamp (8,58 ha) and precipitation sum of 555 mm. 18% increase of water capacity was observed in wet year (1987) In this year the sum of precipitation was 100 mm higher than multiyear average sum. Meanwhile 62% decrease of water capacity was observed in dry year (2003), when the precipitation sum was 208 mm lower than multiyear average one.

In an attempt to assess the needs of the modernization of the North Channel of Obra, the construction began in 1852. The condition of drainage occurring on this course coming generally from the early 20th century and is unsatisfactory. This is the result of longstanding neglect and lack of maintenance. The first modernization works started in 1986. Undergoing on the North Channel of Obra are primarily made in the framework of four tasks, which was the regulation of the water course on a length of approximately 35 km 8 dams were built and 9 dams were demolished. The cost of upgrading the North Channel of The Obra was significantly different, what is the result of the works. They include the cost of reconstruction of the drainage channels, and the reconstruction of hydraulic structures. At this work, in addition to the needs assessment of the North Channel of Obra, further modernization needs were indicated.