Each sampling site is checked for chemical water quality four times during the field season. This produces four samples per site right across our catchments. We use a two-stage process. The first involves obtaining the sample and using an electronic probe for recording supplementary data. The second stage involves laboratory analysis of each sample.
Sampling Officers put a Hach HQ30d Rugged Multi-probe into a bucket of water from the site. The following measurements are recorded onto the device’s memory for downloading later:
In addition, the Sampling Officers gather water samples for laboratory analysis using traditional procedures.
The following chemical parameters are analysed in our laboratory:
As part of the biological and chemical monitoring of freshwaters, it is necessary to undertake a quality assurance programme. Essentially this involves two main stages:
The former involves a random assessment of techniques across the catchments. It allows for standardisation across the Agency and helps minimise inaccuracies.
In the latter, outside laboratories are used to verify results from our own laboratories.