Scotland's water quality monitoring summary report 2024
Introduction
Our 2024 Water Quality Monitoring Summary Report presents findings from our first full year of monitoring using our innovative new analysis methodology for detecting organic chemicals in the water environment, our Liquid Chromatography with High Resolution Mass Spectrometry (LC-HRMS) programme. Samples were analysed concurrently for 18 targeted substances and screened for 463 suspect substances. The substances analysed included pesticides (fungicides, insecticides and herbicides) and both human and veterinary pharmaceuticals.
In 2024, we collected a total of 820 water samples from over 270 surface water locations (rivers, lochs and canals) across Scotland. We also collected 24 samples from 24 groundwater locations, mainly in the east of Scotland. Groundwater monitoring, focusing on higher risk regions, was undertaken as a precursor to a wider national groundwater monitoring plan for trace organics in future. Groundwater locations were sampled once in 2024.
What we found
Chemicals were commonly detected in Scotland’s water environment at the locations sampled in 2024. This is similar to the results reported from other monitoring programmes of this type in Scotland and the UK. In part this is due to the sensitivity of the analysis, which can detect substances at concentration in the low nanogram per litre range (ng/l or in the range of one billionth of a gram in a litre of water).
Finding a substance is present does not necessarily indicate that substance poses a risk, but it does allow us to understand what is there and also to understand how interventions may change that.
Surface waters
In 2024 in surface waters, in total we detected 99 different chemicals. 14 were from our targeted list and 86 from our suspect screening list.
49% of surface water samples collected had at least one substance detected. The location with the highest number of substances detected (33 in total) was the Back Burn at the A6093 road bridge, near Haddington.
The most frequently detected substance in surface waters in our monitoring in 2024 was azoxystrobin, a fungicide used in plant protection.
Groundwater
In groundwater, in total we detected 22 different chemicals. 3 were from our targeted list and 19 from our suspect screening list. 54% of groundwater samples contained at least one substance.
The most frequently detected substance in groundwater in our monitoring in 2024, was atrazine, a herbicide withdrawn in the UK in 2004. Its continued presence in groundwater reflects its relative persistence.
What next
Monitoring in surface water and groundwater will continue through 2025 and 2026 and datasets and reports will be published as they become available.