My latest venture into the world of fieldwork was signing up to the Westcountry Rivers Trust’s ‘Citizen Science’ scheme. After filling in a quick form on the Westcountry Rivers Trust website and receiving my login details, I became part of a team of freshwater monitors who are taking the time to step out into the great outdoors and take samples from their local river.
There is a great need for our fresh water resources to be managed more sustainably and, to tailor our management to each river catchment, we need as much information about what is going on in the river as possible. The vast length of rivers in the West Country means that the assistance of volunteers from the community is a huge help to the successful management of our rivers and their future protection. Every measurement teaches us a little more about how water quality changes throughout the length of a river and, as volunteers are encouraged to take 4 samples a year, we can understand more about how water quality changes throughout the seasons.
Keen to play my part in protecting rivers and interested to learn more about my local river, I logged into the website and explored the multitude of information, quizzes and other citizen scientists’ records from across the world. Before being sent my freshwater monitoring kit, I was asked to watch a short video and complete a quiz, both of which could be finished in 20-30 minutes.
So… decked out with wellies and my personal water monitoring kit, I stepped out into the fresh air and made my way down to the river. The chosen river, in my case, was the River Back, a tributary of the River Tone which begins its life on the lower edge of the Quantock Hills of Somerset. Not only did easy access make this a good choice of sample site, but I was also swayed by my curiosity about the water quality in the river that flows past my childhood home and how it is being influenced in a largely agricultural area.
There are five stages to the freshwater monitoring sample:
Photographing the site
Firstly a photo is taken of the river which allows you to show the nature of the sample site, the water level and the
surrounding landuse. This also gives you the chance to compare the site between visits.
Notes on the river
Then, in the second stage of the monitoring you are asked to make notes on the hydrological conditions of the river. How fast is the flow? What is the landuse? Is there algae present?
Nitrate and phosphates
With notes made (either uploaded straight onto the programme’s app or filled in on a printed datasheet to be uploaded later) and a photo taken, the next stage is to take the nitrate and phosphate measurements. Nitrates and phosphates levels are an important indicator of water quality. When the concentrations of these nutrients are increased (for example, as a result of sewage, manure or fertilisers), the balance of the ecosystem is disturbed. High nutrient levels allow excessive algae growth which uses up the oxygen in the water, causing fish kills and outcompeting other species.
This was where a little DIY was in order, with a re-engineered milk bottle suspended from a bamboo cane, I took a scoopful of river water without the need to get my feet wet or disturb the sediment. To measure nitrate and phosphate, a simple testing kit has been produced, which allows you to draw water from the sample into a small plastic tube (by squeezing out half of the air). The nitrate or phosphate reacts with powder inside the tube and after 3 minutes (5 minutes for phosphate), the colour of the sample can be compared to the colour charts to give the measurement.
Turbidity
The final stage of the freshwater monitoring is to measure turbidity based on how much water can be added to the turbidity tube before the cross is no longer visible. Turbidity gives you an idea of the amount of sediment suspended in the water. Sediment is a major polluter of river courses and so gives us a good idea of the water quality. When sediment enters the river system it can smother fish eggs, clog the gills of fish and prevent light from reaching instream vegetation. Sediment also traps and carries all sorts of other pollutants to the river system from across the river catchment.
Exploring the website
Having made and uploaded my observations and measurements, I was keen to see how my sample compared to others in the local area. I was relieved to find that my sample point was considered to have good ecological status. Moreover nitrates, phosphates and turbidity levels were lower than the global average although were higher than the average for my local area. Overall, it seems that the River Back at the my sample site has a good water quality but I will be interested to see how this changes in my further three samples through the year as land use and weather patterns change.
Click here to become a Citizen Scientist!