This data set comprises of hourly water quality monitoring and flow data of a site within the River Loddon catchment, UK, from September 2017 to September 2018. Parameters measured were temperature, conductivity, pH, ammonium, turbidity, dissolved oxygen, UV-Vis spectral scan from 197-720nm. Daily samples were also taken at 9am GMT and occasional storm samples were taken hourly and then analysed in the laboratory for pH, conductivity, turbidity, total suspended solids, non-purgeable organic carbon, UV-Vis spectral scan from 200-800nm and 12 pesticide concentrations: 2-4-D, Bentazone, Carbendazim, Carbetamide, Chlorotoluron, Clopyralid, MCPA, Mecoprop, Metaldehyde, Propyzamide, Quinmerac and Metazachlor. This data was created as part of the TWENTY65 project, funded by the Engineering and Physical Sciences Research Council (Grant number: EP/N010124/1) and with some additional funding from Affinity Water and Syngenta. Full details about this dataset can be found at https://doi.org/10.5285/331659d7-da72-48a2-9b52-63c003557990

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