EA Water Quality Continuous Monitoring Sonde Historical Locations (Up to March 2022)

The Environment Agency National Water Quality Instrumentation Service provide multi-parameter sondes for continuous sampling of river water quality which are deployed for weeks or months at a time to inform pollution investigations. The data can be used to identify intermittent sources of pollution which infrequent spot sampling will miss. Past locations of EA continuous water quality monitoring sondes deployed up until March 2022. Data from the sondes are available via the Meteor platform on request from the EA. Contact Pippa Tucker to request access. Current deployment locations and live data can be viewed via the Meteor platform. During 2022 we will be working with EA to establish a regular update cycle for this dataset and to develop training webinars to help understand and interpret continous water quality monitoring data. Contact [e-mail] if you would like more information. Update May 2022 - would you like open access to the historical data? Tell EA and Defra what you would like to see published on the Defra Data Services Platform via this survey: https://forms.office.com/r/QmUV2iDwFJ The following parameters are recorded by the sondes: Temperature - In rivers can range from 0 - 25°C. Effluent discharges may be warmer then the receiving watercourse and discharges of groundwater may be cooler then the receiving watercourse. These discharges may distort the normal temperature profile. Water temperatures change with the seasons and will also change throughout the day due to ambient air temperature. Conductivity - This is affected primarily by the geology of the area. It represents the amount of inorganic dissolved solids (such as sodium, sulphate, chloride, calcium) in the water. Inputs from discharges and runoff can change this background level. A drop in value is a good indicator of rainfall. Dissolved Oxygen - Is one of the most important indicators of the health of a river and it is necessary to sustain aquatic life. The concentration is reduced by the respiration of living organisms and replenished by photosynthesis of aquatic plants and algae. In addition, increases in dissolved oxygen are driven by re-aeration from the atmosphere and turbulent flow. This dynamic change is most clearly observed as diurnal patterns in the dissolved oxygen data. pH - An indicator of the acidity or alkalinity of water. Ammonium - The presence of ammonium in a waterbody can be an indicator of pollution. It is associated with the natural decomposition of organic material, the input of sewage (both treated and untreated) or chemically derived commercial fertilisers entering the watercourse. Ammonium levels can also be increased by the presence of interfering ions found in sodium and potassium salts. The source of these may be natural or manmade. Ammonium / Ammonia levels do not directly relate to bacteriology counts. Turbidity - Is a good indicator of the amount of suspended solids in the waterbody. It is caused by either the resuspension of sediment from the bed of the river or other materials entering the watercourse during storm events. Very short transient spikes may be observed; these are due to aquatic organisms moving across the sensor.