The dataset consists of solute concentrations (Potassium, Calcium, Magnesium, Iron, Sodium, Aluminium, Phosphate, Nitrate, Ammonium, Chlorine, Sulphate), also pH and suspended solids, in waters sampled from clear felled and standing Sitka spruce (Picea sitchensis) forest ecosystems in Kershope Forest, Cumbria, UK. Water samples were collected from the ecosystem of a Sitka spruce plantation at weekly intervals for six years. The drainage system of the site had been designed to divide the plantation into a series of artificial catchments, three of which were designated experimental plots and clearfelled in the second year of sampling while three others were the control plots which remained unfelled until the end of the study. This work formed part of a programme of field and laboratory work to determine the effects of felling plantation forest on soil processes. Samples were collected by staff from the Institute of Terrestrial Ecology (ITE) between 1981 and 1987. Full details about this dataset can be found at https://doi.org/10.5285/3f22ef89-22d3-4876-a99e-7ee28f775e0e