HIGH levels of pollutants have been found in waterways across the Fishponds area in sampling by ‘citizen scientists’.
Every summer the Bristol Avon Rivers Trust calls on volunteers to collect samples from waterways across the region to test them for common pollutants, including phosphates and nitrates.
This year more than 130 volunteers collected 202 samples in early July.
The results, published by BART, showed that locally, high nitrate and phosphate pollution was found at various points on the River Frome as it flows through the area.
Samples were taken at 17 points between Frenchay Bridge and the M32, including Snuff Mills (pictured above), Wickham Bridge and Eastville Park.
Some volunteers recorded medium or low levels of pollutants but BART says that overall, levels in the river are high through the area.
Volunteers also reported seeing plastic bottles, food wrappers, cans, laughing gas cannisters and footwear in and around the river.
Invasive species found
Invasive species Himalayan balsam and giant hogweed were also spotted, along with wildlife including dragonflies, ducks and swans.
Samples were also taken from Fishponds Brook, which runs into the Frome from near Everest Road, with high levels of phosphates and nitrates found at two points.
A stream running through Vassalls Park from near Goffenton Drive allotments to the Frome also had high levels of pollutants, with dog waste bags and crisp packets and “grey/white” water reported.
BART says nutrients, particularly phosphates and nitrates, are among the most common pollutants of freshwater worldwide, and widely used as indicators of water quality.
Although they occur naturally in healthy rivers, high concentrations lead to harmful algal blooms which can harm other plant life and fish.
High levels are caused by fertilisers, manure, sewage, urban surface water run-off and household products like detergents.
Across the region, BART said 69% of samples had high nutrient loads of phosphate and nitrate combined, with 3.5% recording low nutrient levels.
However, this was an improvement on last year, when 88% of samples confirmed high nutrient loads and only one out of 290 samples showed low nutrient concentrations.
BART chief executive Simon Hunter said: “The Bristol Avon RiverBlitz provides a snapshot of the catchment’s water quality during a week in July.
“While it may not offer detailed insights into individual streams, the expanding dataset from multiple years reveals trends across the catchment.”
Water quality and health of wildlife affected
He said that as well as in the Frome, high pollutant levels were also recorded along the River Trym and the Avon between Bristol and Bath, with only 5% of samples showing low nitrate levels.
Mr Hunter said: “The data collected suggests, during the week of the Bristol Avon RiverBlitz, that nutrient pollution is likely impacting water quality and, consequently, the health of some watercourses and wildlife across the Bristol Avon.”
He said this year’s milder summer may have resulted in lower nutrient levels than in the previous two years’ surveys, adding: “It’s important to note that the Bristol Avon RiverBlitz captures water quality measurements at a specific moment in time, and there are several other parameters we did not test that could also impact river health, such as bacterial and chemical readings.”
To view figures from the survey visit bristolavonriverstrust.org/riverblitz.