Risk management in water distribution system operation and maintenance using Bayesian theory / B. Tch�orzewska-Cie�slak & K. Pietrucha-Urbanik -- Differentiation of selected components in bottom sediments of Poland's Solina-Myczkowce complex of dam reservoirs / L. Bartoszek, J.A. Tomaszek & J.B. Lechowicz -- The role of wetlands in the removal of heavy metals from the leachate (on the example of the Lipinka River catchment, southern Poland) / T. Molenda -- The possibilities of limitation and elimination of activated sludge bulking / M. Kida, A. Mas�o�n, J.A. Tomaszek & P. Koszelnik -- Lakes and reservoirs restoration : Short description of the chosen methods / L. Bartoszek & P. Koszelnik -- The use of keramsite grains as a support material for the biofilm in moving bed technology / A. Mas�o�n & J.A. Tomaszek -- A review of current knowledge on N2O emissions from WWTPs / J.A. Tomaszek & J. Czarnota.