Citizen Science In Action

We are a small group of citizen scientists (Ian, Mary, Maggie & Alan) testing the Newton Brook in Hereford under the auspices of the Friends of the River Wye. Newton Brook is a small tributary of the River Wye; our three test sites are shown as purple squares in Figure 1.

Figure 1: Newton Brook Watercourse with Location of Supermarket New Build Indicated

Just to the south of our test sites, a supermarket is under construction (black outline) which will involve drainage of the large pond shown to create a car park. Planning permission requires the pond is only drained between September and March for environmental and ecological reasons.

On Wednesday 16th July 2025, a member of the public contacted Maggie to say she thought they had started to drain the pond, so Maggie & I went to investigate. As we followed the footpath alongside the Newton Brook, we could clearly hear what sounded like a small waterfall. On closer inspection this turned out to be a pipe carrying pumped water into the brook (Video 1). The approximate location of the pipe is indicated by the red line in Figure 1.

Video 1: Locating Pollution Source of Newton Brook (16th July 2025)

A close-up view of the pipe effluent (Video 2) showed it to be heavily polluted water (high turbidity). The coffee-coloured water was similar to that often seen polluting the River Wye catchment when the red soil, for which Herefordshire is famous, is washed off bare agricultural fields into the rivers and brooks.

Video 2: Close-up of Dirty Water Being Pumped into Newton Brook

Using my trusty three metre pole sampler (Photo 1) ...

Photo 1: Extendable Pole Sampler and my Brompton Bike

... I collected a sample from the brook directly below the pipe exit for later testing at home.

Photo 2: Brook Water at Pollution Source

Maggie & I then went round to speak to the site manager to request they stop pumping the dirty water into the brook. At this point, we thought they had started emptying the pond which would have been in violation of their planning permits. The site manager did agree to meet us at the gate after Maggie reminded him that we would be informing the Environment Agency of the pollution incident.

We were told that the pumped water did not originate from the pond but from a separate area where they were excavating a pit for a large underground tank. The pit was continuously flooding as they were digging below the water table, hence the need to pump out the water. The site manager was polite and courteous and even allowed us on site to view the digging/pumping operation from a safe distance. He provided us with the contact name and phone number of the person at the supermarket who was project managing the whole scheme.

Maggie & I thanked the site manager and returned to our normal testing downstream of the pollution incident (see Figure 1, purple squares). On the way back, we stopped briefly to collect a sample where Newton Brook goes under the road (Glastonbury Close, see Figure 1) as the brook was both fuller and more turbid than when we passed it on the way to investigate the pollution incident (Photo 3 & Photo 4)

Photo 3: Turbid Newton Brook at Glastonbury Close

Photo 4: Filling a Sample Bottle with Turbid Brook Water

After completing the routine tests at our three designated sites, we agreed to split the followup tasks. I would ring the Environment Agency's pollution hot line and Maggie would contact the project manager at the supermarket. Before hopping onto my trusty steed (Brompton Bike, see Photo 1), I noticed that one of our test sites had become decidedly more turbid (Photo 5) since I had tested it not half an hour ago.

Photo 5: Site U034 after Pollution

Whereas the turbidity of this part of the Newton Brook had been less than 12 NTU when tested earlier that morning, it was now recording a turbidity of 200 NTU. The pollution was making its way down the brook and would soon be entering the River Wye.

On returning home, I decided to ring the Environment Agency (EA) straight away rather than do some further tests that would better describe the nature of the pollution; they could wait till later. The EA hotline was answered quickly by Dan and he took down the details: type of pollution, potential impact of the pollution, location, my contact information. Note to myself: the EA use what3words for pinpointing locations. I made a note of my incident number and Dan said they would get their local team on to it.

A couple of hours later, Maggie let me know that she had rung the supermarket's project manager who had informed her that someone from the EA's Shrewsbury Office was onsite and had shut down the pumping operation. All dirty water was now to be transported offsite and not dumped in the brook. The supermarket claimed they had been misinformed by their ecology consultants.

Back home, I was able to perform some extra tests on the three samples of polluted water that we had collected: at the pollution site, downstream at Glastonbury Close and, finally, at one of our normal test sites (U034). Sample turbidities determined by nephelometry are listed in the table below. These values indicate very high pollution levels; for example, turbidities >10 NTU cause short-term stress to aquatic life while values >100 NTU are unsafe for aquatic organisms.

Site Description	Nephelometric Turbidity (NTU)
Pollution Source	14,150
Glastonbury Close	665
Testing Site U034	190

Thanks to the Environment Agency's quick intervention, a significant pollution event was averted.