On site measurements of pH, conductivity and temperature for thirteen sites in the Humber catchment and three sites in the Tweed catchment within the period 1994 to 1997 as part of the Land Ocean Interaction Study project (LOIS). Sites were sampled at regular weekly intervals and more intermittently during high flows (on average an extra sampling once a month per site). Samples were obtained using a wide neck PTFE bottle in a plastic covered bottle carrier (lowered from bridges where possible otherwise collected by immersing sample bottle by hand in the water as near the main flow as possible). pH and conductivity reading were taken using Mettler Toledo Check Mate meters and probes. Temperature readings were obtained using a PT 100 probe with a Digitron 3204 Pt meter (RS components). The measurements were carried out by members of the field sampling team at York University, as part of the Land Ocean Interaction Study (LOIS). Full details about this dataset can be found at https://doi.org/10.5285/329cbe8f-a292-4c5f-a15a-6528774dbee7

Micro-organic herbicide levels in river water for various sites within the Humber and Tweed catchments collected as part of the Land Ocean Interaction Study project (LOIS). The dataset contains data for Phenyl urea and Phenoxy acid herbicides, measured as 2,4-Dichlorophenoxyacetic acid, 4-(4-Chloro-O-tolyloxy) butyric acid, 4-Chloro-O-tolyloxyacetic acid, Chlorotoluron dissolved, Diuron dissolved, Isoproturon dissolved, Linuron dissolved, Mecoprop dissolved. Phenyl urea herbicide data is available for twelve sites in the Humber catchment within 1994 to 1995 and 1994 to 1997 and for three sites on the Tweed catchment within 1995. Phenoxy acid herbicide data is available for six sites (S1, U3, N4, W5 and O6) over the period December 1994 to September 1995, for 7 sites (S2, D7, A8, C9, D10, T11 and O12) over the period December 1994 to February 1997 and 3 sites (TW13, TW14 and TW15) over the period January 1995 to September 1995. Attempts were made to sample the sites at weekly intervals. However sampling was halted for short periods when it was not possible to process the samples quickly. Linuron dissolved was only measured from April 1994 - October 1994. Samples were collected in chromic acid-washed 1 litre glass bottles. Herbicide levels were concentrated before being measured using High Performance Liquid Chromatography for Phenyl urea herbicides and Gas Chromatography for Phenoxy acid herbicides. Until November 1994, analysis was completed by the York University and the Institute for Freshwater Ecology, Wareham, laboratories. From December 1994 onwards the samples were dispatched to the Institute for Hydrology, Wallingford, for extraction and analyses. Full details about this dataset can be found at https://doi.org/10.5285/e28ffc01-880d-423f-acb6-879b9fd4603a

Polychlorinated biphenyls (PCB), chlorobenzenes (CB) and organochlorine pesticides (OC) data from river water collected at various sites within the Humber catchment area as part of the Land Ocean Interaction Study project (LOIS). Data were collected at regular weekly intervals and intermittently during periods of high flows. All sites were samples from early 1994 to the end of 1996 except for O12, which was sampled from November 1994 till November 1996. The sampling was carried out by the LOIS team at York University. The unfiltered samples were transported to the Institute of Terrestrial Ecology, Monks Wood, UK, where they were extracted with hexane, cleaned up by alumina column chromatography, concentrated and then analysed for CBs by Gas Chromatography-Mass Spectrometry (GC-MS) and PCBs and OCs by Gas Chromatography with Electron Capture Detection (GC-ECD). Full details about this dataset can be found at https://doi.org/10.5285/40ba6fd0-3d41-4520-8d78-cc8c893fd974

Discrete data for major ions and nutrients in river water for 13 sites in the Humber catchment over the periods 1993 to 1997 and 1996 to 1997 and for 3 sites from the Tweed catchment over the period 1994 to 1997. Ions and nutrients measured were: Ammonia, Calcium (dissolved), Magnesium (dissolved), Potassium (dissolved), Sodium (dissolved), Bromide-ion, Carbon (organic dissolved), Chloride-ion, Nitrate, Nitrite, Phosphorus (soluble reactive), Phosphorus (total dissolved), Silicate (reactive dissolved), Sulphate, Carbon (organic particulate), Nitrogen (particulate), Phosphorus (total). Sites were sampled at regular weekly intervals and more intermittently during high flows (on average an extra sampling once a month per site). Samples were obtained using a wide neck PTFE bottle in a plastic covered bottle carrier (lowered from bridges where possible otherwise collected by immersing sample bottle by hand in the water as near the main flow as possible). Samples were filtered through Whatman 0.45um sterile membrane filters immediately on return to laboratory. Samples stored in sterilin tubes in the dark at 40C and analysed by Dionex DX100 ion chromatography system. Silicate reactive dissolved and Chloride-ion concentrations were determined by automated colourimetry and dissolved organic carbon concentrations were determined using a TOCsin II aqueous carbon analyser. Some samples on the River Aire were collected using EPIC automatic samplers. The analysis was carried out by members of the analytical chemistry section at York University (from April 1994 until November 1996) and at Wallingford Institute of Hydrology (September 1993 to April 1994 and December 1996 to April 1997), as part of the Land Ocean Interaction Study (LOIS). Full details about this dataset can be found at https://doi.org/10.5285/4482fa14-aee2-4c7f-9c62-a08dc9704051