Reynolds, B.; Neal, C.; Kirchner, J.

Vyrnwy research catchment hydrochemistry

This dataset includes weekly data from monitoring of stream, rainfall and groundwater hydrochemistry in the Vyrnwy research catchment between 1994 and 2001. Data for over 50 chemical determinands are presented alongside data for some in-situ measurements such as water temperature. Full descriptions of the analytical methods used for each determinand is included. Intensive and long-term monitoring within the catchments underpins a wealth of hydrological and hydro-chemical research; other linked datasets include river flow, meteorology and a variety of detailed spatial datasets representing the topography, soils and rivers of the catchments. Monitoring is funded by the Centre for Ecology & Hydrology.

Publication date: 2013-02-08

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Licence terms and conditions apply

Format of the dataset : Comma-separated values (CSV)

You must cite: Reynolds, B.; Neal, C.; Kirchner, J. (2013). Vyrnwy research catchment hydrochemistry. NERC Environmental Information Data Centre.


you must acknowledge the following resource: Neal, C., Reynolds, B., Kirchner, J.W., Rowland, P., Norris, D., Sleep, D., Lawlor, A., Woods, C., Thacker, S., Guyatt, H., Vincent, C., Lehto, K., Grant, S., Williams, J., Neal, M., Wickham, H., Harman, S., Armstrong, L. (2013) High-frequency precipitation and stream water quality time series from Plynlimon, Wales: an openly accessible data resource spanning the periodic table. Hydrological Processes, in press.


Study area
Temporal extent
1994-10-07    to    2001-02-16

Supplemental information

Other useful information regarding this dataset:

Neal, C., Reynolds, B., Norris, D., Kirchner, J. W., Neal, M., Rowland, P., … Wright, D. (2011). Three decades of water quality measurements from the Upper Severn experimental catchments at Plynlimon, Wales: an openly accessible data resource for research, modelling, environmental management and education. Hydrological Processes, 25(24), 3818-3830.

Provenance & quality

Originally designed to improve understanding of water use by coniferous forests, monitoring within the Plynlimon/Vyrnwy research catchments has subsequently developed into a multi-disciplinary project underpinning a wealth of hydrological research. The stream hydrochemistry dataset is a combination of chemical determinands and in-situ physical properties. Samples are taken on an approximately weekly basis and analysed in laboratories for approximately 50 chemical determinands. The laboratory analysis has been undertaken at different locations using different equipment during the years of monitoring represented within the dataset. Details of the analytical methods used for each determinand are included within the dataset. The information provided is presented as raw data which have not been modified to include "less than" values when the numbers are less than the lowest quotable value. This is done so as to allow the data to be used for research purposes including detailed statistical analysis where inclusion of less than values would be problematic. The data are thus "uncensored" for research purposes and include in places values that are negative due to analytical uncertainties and the extremely low concentrations of some of the determinands. The data are provided in good faith with the expectation that they will be used in a positive and constructive manner. It is up to the user to resolve which way to use and interpret the data and information on full methodologies and less than values is provided within the metadata files. We whole heartedly encourage the use of these data for research and educational purposes bearing in mind that it is uncensored data and that over the years research directions have evolved to reflect changing project and funding priorities while analytical methodologies have changed. The data provide a legacy from many years' research involving scientists, analysts and field workers who in many cases have now retired. While we have done our best to provide all the information possible, in many cases it will be not be possible to respond to detailed enquiries about the earlier parts of the record.

Correspondence/contact details

Norris, D.
Centre for Ecology & Hydrology
Environment Centre for Wales, Deiniol Road
LL57 2UW Bangor
Unitied Kingdom


Reynolds, B.
Centre for Ecology & Hydrology
Neal, C.
Centre for Ecology & Hydrology
Kirchner, J.
ETH Zurich

Other contacts

Environmental Information Data Centre
NERC Environmental Information Data Centre


Spatial representation type
Tabular (text)
Spatial reference system
OSGB 1936 / British National Grid


Topic categories
Inland Waters
groundwater,  hydrochemistry,  rainfall,  river,  stream,  United Kingdom Vyrnwy,  Wales water quality,  Water quality Water Resources weekly
Environmental Monitoring Facilities