River Itchen damage below Alresford Salads: Autumn 2018 photos

New photos show damage in River Itchen below Bakkavor's Alresford Salads factory.

At S&TC we have long been campaigning to stop Bakkavor discharging their salad wash effluent into the headwaters of the River Itchen.

The Itchen is a designated Special Area of Conservation (SAC), and we fear that the chemicals in their discharge are harming the environment.

Read more: Chlorine in our conservation areas?

Read more: Toxic chemicals keep coming

Our latest autumn samples of invertebrates and algal growth, from a site just downstream of the Bakkavor factory, reinforces our concern.

Our autumn river bed photos, and samples of invertebrates and algae, taken on 5 October 2018, immediately downstream of the Bakkavor salad washing factory (Alresford Salads), show the Itchen headwaters remain heavily polluted. This is in stark contrast to the condition of the Upper Test.


Excess algal slime demonstrates damage

The bed of the Itchen headwater stream at our sample site is covered in algal “slime”.

This is a short distance downstream from Bakkavor’s salad washing factory’s discharge point.

River Itchen photos

The bed of the stream should show clear, un-sedimented gravel like this photograph of the Test headwaters at Polhampton taken last Autumn:

Dr Nick Everall of Aquascience has analysed this sinister algal growth. This is what he reports:

“There was extensive area coverage (over 90%) of the river bed area with the thick biological growth or slime which upon microscopic examination was, aside to a bit of chalk and sediment adhesion, entirely composed of filamentous and attached algal and lesser fungal growth…

The dominant and major composition of the biological growth covering metres of the bed of the River Itchen below Alresford Salads was, often filamentous, algae (diatoms, blue-greens and green algae) with some fungal component…

It was typical of organic and nutrient enriched benthic ‘slime’ or sewage fungus’ (Fjerdingstad, 1964 and Hellawell, 1986).”

Read Dr Nick Everall's October 2018 report here

Invertebrates (or lack thereof)

The invertebrate sample from the Itchen headwaters was devoid of insects sensitive to pollution. There were no mayflies or gammarus.

The associated biometric measurements indicate an impact from pesticides, siltation, nutrient enrichment (phosphates) and organic pollution.

In short, the lack of invertebrates signifies the water quality is extremely poor in general – and exceptionally so for the headwaters of a Special Area of Conservation chalkstream.

Read Dr Nick Everall's October 2018 report here

The Upper Test sample taken in autumn 2017 was dramatically healthier. There were over 1800 gammarus and two species of mayfly, for starters. The biometrics indicated no impact from siltation, phosphates or organic pollution.


What are we doing about it?

We were so horrified by the invertebrate sample taken in May 2018 from the same Upper Itchen headwater site that we formally notified the Environment Agency (EA) to investigate the problem.

Read more: Alresford Salads EDR

That investigation is continuing; meanwhile we will share our latest findings with the EA, whom we are also fighting to stop Bakkavor discharging its salad wash effluent into the headwaters of the Itchen.

Read more: Will Alresford Salads end use of their chorine-free cleaning products?

In response, the EA is seeking a variation of Bakkavor’s discharge consent, but progress is painfully slow.

Overall, our data is providing strong evidence for the EA to insist Bakkavor stops pumping its effluent into the river. This is the only environmentally acceptable outcome.

As Nick Measham, Deputy Chief Exectuive of S&TC, summarises:

"It is a nonsense that biocides are discharged into any watercourse, let alone the headwaters of an SAC.

Such chemicals can be highly toxic to aquatic life, negatively impacting the health and abundance of wild salmon and trout in our waters - as well as all the other creatures that live there and together sustain freshwater's delicate ecology.

Has the EA got the courage to say no, or will industry triumph over one of Britain’s natural wonders?"

Agricultural Bill: Is a ‘Green Brexit’ possible?

The first major Agriculture Bill for over 70 years has now been published, promising a cleaner, greener and healthier environment post Brexit

Currently farmers receive €4 billion in subsides each year, which is divided up related to the total amount of land farmed. For current subsidies farmers do not need to ‘do’ anything.

The new Bill proposes farmers are paid for delivering public goods; things we cannot buy in a shop, like clean water, flood attenuation, thriving wildlife and healthy soils.


Funding a 'Green Brexit'

The headlines are good. But as with everything, the devil will be in the detail.

This new approach will need substantial investment and coordination to ensure the right public goods happen in the right places for people and wildlife.

And the big elephant in the room is the funding. How do the Government plan to fund their ‘Green Brexit’? No details have been given on this so far.


Carrot vs Stick

The Government reiterated at the launch that they were committed to:

“maintaining a strong regulatory baseline, with enforcement mechanisms that are proportionate and effective”.

This is where we at S&TC have the greatest concern.

Current enforcement is just not fit for purpose. It is totally under-resourced.

We are all for having a big juicy carrot for farmers, but it must be accompanied by an equally proportionate stick where required.

The data from our own Riverfly Census indicates that many rivers in England and Wales are suffering from the impacts of excess phosphates and fine sediments from poor agricultural practices. This impacts wild fish populations, from smothering their spawning redds, to reducing the invertebrates they feed on.

For the small minority of farmers which do pollute, sometimes repetitively, strong action must be taken.


What happens next

The Bill proposes a long timetable, where the current system of payments under the Common Agricultural Policy will continue until 2021, then a seven-year transition period to the new system, where the old payments will gradually taper off.

Like most environmental charities, we have lobbied for years for this vision where farmers are rewarded for delivering for the environment- creating a sustainable future for farming and the environment alike.

We will see over the next few months, as the Agriculture Bill makes its way through Parliament, if that vision can survive.

However, in order to achieve a truly cleaner, greener and healthier environment post Brexit, enforcement, or the current lack of it, must be addressed too.

To help us take action against agricultural pollution visit our ‘see it, photograph it, report it’ campaign.


By Dr Janina Gray, Head of Science & Policy at S&TC

River Itchen pollution: Alresford Salads trial chlorine-free cleaning products

Is the end of chlorine-based cleaning products at Alresford salad washing plant finally in sight?

Finally, it appears Alresford salad washing plant is planning to stop using chlorine-based cleaning products.

This would mean that there would no longer be any products used to wash the site’s equipment that could react to form chloramines, which are highly toxic to water life even in very low concentrations in water.


A small win for S&TC

At S&TC we have been campaigning for this for a long-time.

Our own Riverfly Census invertebrate data and phosphate monitoring on the Itchen in recent years indicate that the river is far from a pristine chalkstream.

We feel it is extraordinary that chlorine products are ever allowed to be discharged, insufficiently treated, into any UK river, let alone a Special Area of Conservation (SAC) such as Itchen, the most protected under EU legalisation.

This, however, would only be a small potential win. It is important to remember that any chemicals used to disinfect and clean are, by their nature, toxic.

We do not believe any of these chemicals should be discharged into an SAC river.


More sustainable solution still needed

Applying the precautionary principle, the solution is easy- connect the discharge to the main sewer, as nearby competitor, Vitacress, has already done on the Bourne Rivulet.

Yes, this would be at a cost, but should a multi-million pound industry really be allowed to use an SAC to dispose of chemical waste?


Next steps

On the 10th September, Alresford salad washing plant began a 6-week trial into the new chlorine-free cleaning products for its night-time washing; during which time the EA has requested monitoring of the discharges. Following this:

  • The EA envisage that the updated risk assessment will be submitted to them by the end of October
  • The EA will then undertake consultation with Natural England in mid-December
  • The EA plan to consult the public on their position in February 2019

As always, we will continue to provide updates via our website, social media and email.


Imported pesticides in our chalkstream?

It is worth noting that we have wider concerns beyond the nighttime washing effluent.

We also have concerns about whether pesticides, which may be washed off imported salad that is being processed and bagged at Alresford, could also be ending up in the Itchen.

We plan to do more monitoring to assess this risk and will be requesting to see the EA’s official policy on protecting our rivers from the risks of chemicals washed off imported goods and discharged directly into our watercourses.

In the meantime, I’ll be washing my own salad!


Words by our Head of Science & Policy, Dr Janina Gray

High resolution monitoring is essential for river conservation

This is a re-posting of an original article from Environmental Technology


High Resolution Monitoring on the Itchen

Working on behalf of Salmon & Trout Conservation (S&TC), researchers from the University of Portsmouth have been investigating nutrient concentrations in the Upper River Itchen, in Hampshire, UK, to better understand where phosphorus is coming from and how it is impacting river ecology.

The work has been underway for over three years and Lauren Mattingley, Science Officer for S&TC says:

“Continuous monitoring of phosphorus has improved our understanding of nutrient dynamics in the Itchen.

To date the results from this monitoring have influenced the lowering of discharge limits from watercress companies and trout breeding farms.

The behaviour of phosphorus in rivers is relatively poorly understood, and this is often reflected in water quality standards that, in our opinion, lack the scientific evidence to adequately protect the ecology of the UK’s diverse water resources.

Research such as that which we have commissioned on the Itchen is essential to set informed phosphorus permits to protect water life.”



The Itchen is a world famous chalk stream; renowned for its clear water and high quality fly fishing.

Designated a ‘Special Area of Conservation’ the river supports populations of water-crowfoot, Southern damselfly, Bullhead, Brook lamprey, White-clawed crayfish and otters. The upper river does not suffer from wastewater treatment works discharges, but does support two watercress farms, which have been the focus of initiatives to reduce phosphate concentrations.

S&TC is the only UK charity campaigning for wild fish and their habitats. The organisation’s goal is for UK waters to support abundant and sustainable populations of wild fish and all other water-dependent wildlife. Within its ‘Living Rivers’ campaign S&TC is seeking to tackle two of the major causes of poor water quality – fine sediment and phosphorus. The Itchen is therefore acting as a pilot river for their water quality monitoring initiatives.

Phosphorus in fresh water is a major concern globally; mainly because of its role in the formation of algal blooms and eutrophication, which have a harmful effect on water quality and habitats. Under certain conditions, raised phosphate concentrations contribute to the proliferation of nuisance phytoplankton as well as epiphytic and benthic algae.

Diffuse sources of phosphate include storm water and agricultural run-off from land, and point sources include septic tanks and wastewater discharges from industry and sewage treatment works. Soluble reactive phosphorus (SRP) is the main concern, because of its availability for aquatic organism growth, but other forms of phosphate such as particulate phosphate can contribute to nutrient enrichment.

The EU’s Water Framework Directive (WFD) required the UK to achieve ‘good status’ of all water bodies (including rivers, streams, lakes, estuaries, coastal waters and groundwater) by 2015, but in 2012 only 36% of water bodies were classified as ‘good’ or better.

The UK Technical Advisory Group (UKTAG) published recommendations in 2013 to revise the standards for phosphorus in rivers, because those set in 2009 were not sufficiently stringent - in 75% of rivers with clear ecological impacts of nutrient enrichment, the existing standards produced phosphorus classifications of good or even high status! DEFRA, therefore, revised the phosphorus standards to lower concentrations. However, the SRP concentration limits vary widely according to the location and alkalinity of the river.

Recognising a gap in the understanding of the relationship between phosphorus and aquatic ecology, S&TC has a unique agreement with the Environment Agency (EA) in Hampshire in which key environmental targets have been established for the Rivers Itchen and Test to help drive ecological improvements. The agreed targets are set around the number of key water insects that should be expected in a 3-minute kick-sweep sample. The targets are for the middle and lower reaches of the catchment to support at least 500 freshwater shrimps (Gammarus) and 10 separate mayfly species - all of which are susceptible to different forms of pollution, so their presence provides a measure of the river’s health.

S&TC has also conducted research investigating the effects of fine sediment and SRP on the hatching of the blue winged olive, Serratella ignita (Ephemerellidae: Ephemeroptera) a crucial component of the aquatic food chain. The results found that a cocktail of SRP and fine sediment at concentrations exceeding those found in many UK rivers (25 mg/L fine sediment and 0.07 mg/L phosphate) caused 80% of the eggs in the experiment to die. This unique research highlighted the environmental damage caused by phosphorus beyond eutrophication.


Water sampling and analysis

Five automatic samplers have been strategically located on the river, each collecting daily samples. This generates 120 samples per 24 day cycle, which are collected and transferred to the Portsmouth laboratory. The samples are split into three for the analysis of Total Phosphate, Soluble Reactive Phosphate (SRP) and Total Dissolved Phosphate (TDP).

To accommodate such a high volume of work, the lab in the University of Portsmouth’s School of Earth & Environmental Sciences employs a QuAAtro 5-channel segmented flow autoanalyzer, from SEAL Analytical.

“The QuAAtro has been in heavy use for over 9 years,”

says Senior Scientific Officer Dr Adil Bakir.

“It has been employed on a number of academic and commercial research projects, and is also used for teaching. As a 5-channel instrument, we are able to study phosphate, nitrate, nitrite, ammonia and silicate, but our work on the Itchen is focused on the different forms of phosphate.”

The University of Portsmouth’s Environmental Chemistry Analytical Laboratory provides analytical and consultancy services for businesses, universities and other organisations. Dr Bakir says: “With the QuaAAttro we are able to analyse diverse matrices including river water, sea water and wastewater, and with automatic dilution and high levels of sensitivity, we are able to measure a wide range of concentrations.”


Developing effective discharge consents

The analytical work undertaken by the laboratory at the University of Portsmouth has greatly improved the understanding of the ecology of the River Itchen and thereby informed the development of appropriate discharge consents for the watercress farms.

Effective 1st January 2016, new discharge permits were issued by the Environment Agency that set limits on phosphate discharges to the River Itchen system. For the Vitacress Pinglestone Farm these limits were set at 0.064 mg/L and measured as an annual mean increase compared to the inlet sample. S&TC now works closely with Vitacress, monitoring immediately downstream of the discharge so that the effects of the new discharge limit can be effectively assessed.

Looking forward, Lauren says:

“The lessons that we have learned on the Itchen are transferrable, and do not only apply to chalk streams. All rivers have their issues and inputs, so proper diagnosis and understanding of how these shape the biology is essential to the successful restoration of degraded systems.

In an ideal world, phosphorus targets would be established on a river by river basis, and determined by research and proper monitoring.

River ecology is impacted by a wide variety of factors and while nutrients represent a serious risk, it is important for us to understand all of the threats, and the relationships between them.

In summary, without high-resolution monitoring, river standards will be less reliable and river restoration efforts will be blind to their consequences.”

Dwindling flylife evidences a worrying decline of the River Test

Decline of the River Test

The River Test is one of our most famous, if not the most famous, trout river in the country; yet we have significant evidence that it is sadly in decline.

Furthermore, we can now point the finger firmly in the direction of  Chilbolton and Fullerton Waste Water Sewage Works; or, more aptly, the permits which legally condone their destructive discharge.


How do we know the River Test is in trouble? 

Healthy ecosystems mean healthy waterways; if the invertebrate life is in trouble, then so too is the river. Aside from sustaining the food-chain, river insects are incredibly susceptible to certain chemicals and excess sediment and phosphate, so they also provide an excellent indicator of overall water health and issues.

Unfortunately, our River Test Riverfly Census (full report due in September) records a significant decline in riverfly and gammarus numbers between 2015 to 2017, at the Mayfly Inn.

Moreover, the data provides important evidence of the pressures facing flylife on the River Test, helping us understand what is happening and what can be done to improve the water environment and its wildlife.

Sadly, the decline in flylife on the middle reaches of the River Test is not news.

Dr Cyril Bennett and Warren Gilchrist have charted the decline in the Blue-Winged Olive population at Leckford - just downstream of our Census sample site at the Mayfly Inn – since 1995.

This decline in flylife matters not only for fish and other river creatures – invertebrates are the base of the aquatic food chain - but also for anglers, and anyone else who respects this iconic river and the creatures that reside there.


Why is this decline happening?

Dr Cyril Bennett has now produced a report which, together with our Mayfly Inn results, throws more light on the causes of the problem.

This data show us that elevated levels of phosphate and sediment are the overwhelmingly likely cause of the problem. (Phosphate and sediment, when present in such excess, cause a choking of the river and are essentially destructive to life).

This is supported by the Environment Agency’s own in-river phosphate data. Their data shows that phosphate levels in the Test (at the Mayfly Inn) are consistently at least double than what is expected for a chalk-stream. This has been an increasing ominous trend since 2012.


Decline of River Test


Why is there so much sediment and phosphate?

Two Waste Water Treatment Works (WWTW) discharge into the Test directly above the Mayfly Inn sampling site: Chilbolton and Fullerton.

Chilbolton slashed its discharges in 2007 after an upgrade. Fullerton, a much bigger operation, is reporting a steady increase in its phosphate discharge levels.

Our suspicion is that the Fullerton works is under increasing pressure from the growth of Andover. Both these works have phosphate stripping technology and appear to be within their current consent levels.

The problem, indicated by our results, is that these consent levels are far too high for the river’s ecology. This is a depressingly familiar national story.

The WWTWs are not the only source of phosphate and sediment – septic tanks and agriculture play a role – but they are one main source of the problem.


What is being done?

Based on S&TC's independent research and the work of Dr Cyril Bennett, the Environment Agency is now working with Southern Water to reduce its discharge of phosphate. The long-term target for the river is 30 micrograms/litre with an interim (2021) target of 40 micrograms/litre.

The problem is that Southern Water (and all other water companies) are given far too long (6 years under current regulation) to make these necessary changes.

We continue to lobby to get the companies to up their game sooner rather than later.

Perhaps Mr Gove, or whoever will be the Environment Secretary after the summer holidays, will shorten the investment cycle.

Fullerton was clearly performing much better in the recent past, so why cannot Southern Water act now?


Where can you find out more?

Full results from our survey for the River Test (supported in 2017/2018 by the Test & Itchen Association) will be released in September - please check our Riverfly Census page for more info.

We receive no government funding for our important research, which, critically, allows us to pressure the EA with complete impartiality. If you want to help us protect chalk-streams both locally and nationally, and contribute to the ongoing fight to preserve our precious freshwater ecosystems, then please consider joining us as member or making a donation.



We rely on your support to protect wild fish

and the places they live

By donating or joining as a member you will be making a huge contribution to the fight to protect the UK's waters and ensure a sustainable future for wild fish.

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River Avon: Riverfly Census Results

River Avon Riverfly Census

The results are in from our ground-breaking Riverfly Census campaign for the River Avon. View the results below and read more about what we found, why it is important, and what we are doing next!

What is the River Avon Riverfly Census campaign about?

Our campaign is to reverse the decline in water quality in the Avon. Water quality (or the lack of it) determines the ability of a river to support life.

Our Riverfly Census along the River Avon has revealed significantly less water insects than should be present, trending downwards by up to 50% since 2015, due mainly to excessive phosphorus and sediment in the water.

How does this campaign affect salmon and trout?

Water insects are an accurate measure of water health, and in the River Avon (designated a Special Area of Conservation) they are under significant pressure from phosphorus, sediment pollution and pesticides. We know this from our independent professional surveying - our 3 year-long Riverfly Census - which is unique to S&TC and highly rigorous across the UK.

Specifically, our research has unearthed a surprising decline in Blue Winged Olive flies, a crucial part of the river food web and a staple in any chalk stream. Loss of such an important species definitely indicates a cry for help in the Avon, and directly impacts the health and abundance of salmon and trout. Other stats show distributing downward trends:

  • Over 60% of sites showed worrying chemical footprints in Autumn 2017
  • Over 50% decrease in numbers of different mayflies at Stratford Bridge since 2015
  • Over 52% decreases in the amount of all species at Ham Hatches since 2017

We have summarised these findings into a simple one-page fact sheet, perfect for sharing. Please view this here.

Alternately, we welcome you to view and share the full report and data sheet.

Phosphorus and sediment do occur naturally in rivers in small amounts, but in excessive quantities are lethal to water insects. They promote algal growth, which chokes the river of life and negatively impacts egg development of invertebrates through suffocation. We believe these stressors are responsible for the shortage in these essential insects. The EA have similarly demonstrated that there is too much phosphorus in the river from their own monitoring.

Excessive quantities of phosphorus and sediment can be caused by many things, including fertilisers, septic tanks, road run-off, loose soil from farming practices, dust, dirt, and sewage. Indeed, the Amesbury and Ratfyn Sewage Treatment Works have had an increasing upward trend of phosphorus in their final effluent (2012-2017 data), which we suspect is a large contributory factor.

Overall, the River Avon ranked No.1 in terms of health and vitality in our 2015 Riverfly Census; now in 2018 it has significantly declined and taken a turn for the worst. At some sights, mayfly species had declined almost 40% since 2015, and Stratford Bridge declined by over 50% in 2017 compared to 2015 & 2016.


View the fact sheet, report and data here:

What is our plan to tackle these issues?

At S&TC, our entire model is fact based campaigning. As such, our full technical report from the Avon has been taken to the Environment Agency (the regulator) and other river stakeholders (such as Wessex Water). We are seeking to influence change by finding more conservation friendly ways forward.

Together with SADAC, we have formally registered our concern with the EA that there is too much phosphorus in the river. We are due to meet with them imminently to discuss their response to our request for action.

A nutrient management plan has been developed by the EA and Natural England to address poor water quality caused by phosphorus contributions from the upper catchment, but we are not yet seeing significant results.

We have therefore met with Wessex Water to present our data and concerns regarding the Amesbury and Ratfyn Sewage Treatment Works, and we continue to pressure them to improve discharge.

The next step is further research, to strengthen our case and force the EA to listen. 

How can you help?

The invertebrate data has indicated that the main problem is phosphorus, so we now need further, more specific, independent data to move forward with the EA and produce real change.

We need to raise money to carry out high-resolution phosphorous monitoring on the River Avon, which involves placing chemical monitoring units at specific sites. We already own these units, but sampling costs at each site are upwards of £3,000 a year, and we need to run at least 4 sites (including monitors above and below the sewage treatment works).

We are looking to individuals, businesses and organisations local to the Avon, or passionate about maintaining this iconic stretch of river, to help us meet this goal. Please support us in protecting one of Britain’s finest and most vulnerable chalk streams. Your funds help us in the following way:

  • £14 runs a sampler at one site for one day
  • £50 analyses one sample from one site
  • £100 runs a sampler at one site for a week
  • £3,000 runs a sampling site for an entire year

Additionally, it is important to note that we are taking a much wider view of the issues on the Avon, beyond just sewage. A wider problem, in our view, is bad agricultural practices; which we continue to research into - both the problems and potential solutions - and work with the EA to influence change. This is where longer-term support of our work is vital; and we gratefully thank our members for their ongoing help.

How else can you support us?

In many places the river still looks beautiful, but of course you can’t really see phosphorus. So alongside funding our research, we also need to educate people on ‘invisible threats’ and what is happening beneath the surface. The sharing of this research is the first step in highlighting, and educating on, these unseen issues in the Avon.

Action is required NOW. Over the next 3 to 5 years the pressure on the river will only increase as we expand as a population (for example, there is extensive building in the Avon Valley, and the army is soon re-basing at Salisbury). This means increased pressure on sewage works and increased run-off into the river, so the EA urgently need to establish control.

Please assist us in spreading the word about the opportunities to improve the River Avon by sharing this content with locals, anglers, nature and water enthusiasts, wildlife lovers, relevant NGO’s and charities, and anyone else who may be interested or able to assist us. Download everything you need below:

We rely on your support to protect wild fish

and the places they live

By donating or joining as a member you will be making a huge contribution to the fight to protect the UK's waters and ensure a sustainable future for wild fish.

S&TC Cymru: Snapshot survey of the River Tywi (Towy)

S&TC Cymru has reacted to growing concerns surrounding the prolific algal growth witnessed on the Tywi over recent weeks by conducting a snapshot survey of the most affected part of the river.

Conditions at the time of the visit (11th of June 2018) reflected a prolonged absence of rain coupled with long days of largely uninterrupted sunlight. This had resulted in reduced, but not unseasonably low, water levels.

Algal growth in backwaters and shallows is not untypical under such conditions, but the extent of the observed examples immediately suggested the river to be carrying elevated levels of nutrients:

As local land owner, Sir Edward Dashwood explains:

"I am very concerned about the health of the Towy. Over the last few years there has been a marked decline in the water quality and a huge increase in pollution levels, which is affecting not only fish but all sorts of life in the river."


What does our sampling tell us?

The greater part of the renowned Golden Grove fishery was found to be suffering from extensive growths of filamentous algae (species not identified), to the extent that meaningful kick sampling over much of its length proved impossible:

Ranunculus aquatilis or common water-crowfoot was conspicuous by its absence. The few strands that remained were largely, if not completely, choked with filamentous algae.

Where it was possible to sample, the results revealed abundant numbers of:

  • BWO nymphs (±70)
  • Small cased caddis (±30)

... but low numbers of other groups of riverflies:

  • Baetidae (±10)
  • Heptagenidae (±4)
  • Stoneflies (±10)
  • Caseless caddis (4)

Gammarus (3) were also noticeably few in number.

The relative paucity of the latter groups suggests that their environment is under long term stress, while the profusion of filamentous algae clearly indicates that the river is carrying a nutrient load far in excess of natural levels.

(Sample taken at  51°52'20.6"N 4°00'54.8"W - Google maps link https://goo.gl/maps/caD32dB8DBm )


What is causing such prolific algal growth?

High algal abundance continued above the outfall of a sewage treatment works, indicating that other sources of nutrients must exist upstream of this point.

Furthermore, given the relatively low human population in the surrounding area, it is unlikely that leakage or discharge from domestic sewage services would be sufficient to have such an extensive impact.


What might be the cause of the problem?

Local anecdotal reports of repeated spreading of farmyard slurry across large areas of land within close proximity to the river would suggest that direct run off, or long term leaching, might, at the very least, be a contributory factor.  

As Sir Edward explains:

"Many smaller farms have now ceased dairy farming completely in the Towy Valley, but the few that remain have upped their numbers to an extraordinary level, milking many hundreds of cows each."

Examination of the river at Llangadog, some six miles upstream told a very different story. Ranunculus was flourishing and the river bed showed no signs of algal growth:

This story was repeated further upstream again at Llandovery where fish were seen rising and also on the Afon Bran, a minor tributary where ranunculus grew in profusion:


What can be done?

Despite the brevity of the visit, it is clear from our observations that the Tywi is suffering significant nutrient enrichment along its length between Llangadog and Llandeilo.

Anecdotal evidence suggests that the enrichment may be a consequence of slurry dispersal on fields across the valley floor between these two points, but a further, more detailed investigation would be required to establish whether this is from a single source or more diffuse in nature.

As Sir Edward says:

"Not only is this of concern, but these factory operations can no longer keep their stock on straw in the traditional manner, and there is little place for their slurry to end up, one way or another, but in or near the river.

For the sake of future generations we have to work with them and find a way to help them urgently address these issues."

Should further investigations confirm slurry to be the culprit, the possibility exists of veterinary pharmaceutical products such as antihelmintics also entering the river and impacting upon invertebrate species.

Given the prevailing absence of rain it might also be possible that the nutrients could be leaching from the surrounding area via groundwater. This might explain the persistence of the algal growth in the river and would point to excessive nutrient levels at soil depths, beyond the reach of the roots of grasses and other crops.

In the absence of any other obvious evidence it is highly probable that the algal growth and reduced numbers of invertebrates observed in the River Tywi are indicative of excessive nutrients entering its waters as a consequence of the repeated spreading of farmyard slurry over extensive areas of land on the valley floor.


Dai Roberts (independent Riverfly monitor)

By Richard Garner Williams, S&TC Cymru  

Riverfly Census: Whitewater Sampling

Whitewater River

Although 2017 was the last year for the 12 Riverfly Census core rivers, we continue to work our way through the rivers added later on (as well as assess and write up the data so far).

One such river (Whitewater, a tributary of the Blackwater River) recently led us to work closely with the Whitewater Valley Preservation Society, as we took to various sites throughout Hampshire for some sampling.

Below: Our scientist Lauren takes a peek at some river vegetation

riverfly census whitewater

Below: A section of the Whitewater, near Basingstoke

riverfly census whitewater

Below: Bridge over part of the Whitewater in a small village

riverfly census whitewater

Keeping our waters wild

We are working with groups such as the WVPS, who are in the second year of their sampling, to help keep their waters wild. A lofty aim indeed; one which begins - as all our campaigns do - with sound scientific evidence.

As such, we are helping them obtain species-level water insect data to find out the key issues influencing the biology. This data is a scientifically sound way to understand river pressures and advocate better protection.

Essentially, we use sampling to ask, 'what is happening in this river?'. Based on the answers to that question, we take action.

For more info on the methods that we use, the data that is produced, and the actions it produces, see our Riverfly Census information.

Below: We analyse everything in the lab, but that first peek is always enlightening

riverfly census whitewater


What did we find?

We had a great day sampling six sites along the river, and whilst the true picture cannot be obtained without lab analysis, a quick glance at the samples showed an encouraging range of bugs such as flat -bodied mayflies.

Below: A stickleback, in breeding colours

riverfly census whitewater

Below: Damselfly larvae

riverfly census whitewater

Below: Blue-winged olive

riverfly census whitewater


Invasive species

On a slightly less positive note we also found a significant number of signal crayfish, one of the UK's foreign invaders. These critters burrow into banks, decreasing bank stability and increasing erosion.

They also eat EVERYTHING, including many of our precious bugs - so they are probably munching through a lot of the Whitewater’s invertebrate community.

Below: An Invasive signal crayfish

riverfly census whitewater

Remember to practice good biosecurity (check, clean, dry) to stop the spread and if you find these crayfish, it’s illegal to put them back!

On the subject of good biosecurity, Nick was overjoyed to remove his waders at the end of the day and take them home for a good clean.

Below: The day was a long and hot one, so this task certainly did not lack comedic value.

riverfly census whitewater


Next steps

We await the lab results eagerly, and look forward to further collaboration with the Whitewater Valley Preservation Society.

A huge thank you to the local groups who are employing the Riverfly Census methodology on their own rivers, specifically the Test & Itchen Association, the Whitewater Valley Preservation Society and the Leven group.

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and the places they live

By donating or joining as a member you will be making a huge contribution to the fight to protect the UK's waters and ensure a sustainable future for wild fish.

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Riverfly Census continues in Wales

The Riverfly Census in Wales

Through our S&TC Riverfly Census, a three-year survey using species-level invertebrate analysis, we are currently analysing results from the 12 rivers that kicked the survey off in 2015. We continue to unlock the power of water insects and diagnose the health of rivers nationally- and this is not just limited to England.

The Census method was so well received that in 2016 three Welsh rivers were added to the initial 12 English rivers: the Usk, Clwyd and Eastern Cleddau. This year we are collecting the final samples to complete the three year picture.

We will be analysing the Welsh results early 2019, then taking the results to local stakeholders and campaigning for action.

So far it is clear that current regulations are not rigorous enough to detect the extent of the problems threatening the base of the food chain.

Fact-based scientific evidence like Riverfly Census data can be a great platform to push for better, more effective guidelines to protect our wildlife and a rethink on the existing policies in place.

What is the Riverfly Census?

Water insects live for months, sometimes years, below the surface in their nymph stages. Because different insects have different tolerances to pollution, the presence or absence of certain species is a simple but effective way of finding out what pressures a river might be experiencing.

Using a consistent method of sampling, we are able to evaluate the health of rivers by evaluating the bugs that we find there, and using this data we can take action for cleaner rivers.

Although it is still too early to present the main conclusions of the Census, for the core survey rivers it is a clear fact that deterioration is largely a result of phosphate and sediment pollution, even on rivers with the highest level of conservation protection such as the River Itchen.

Read more about the Riverfly Census here.



Welsh charities join forces for World Fish Migration Day

World Fish Migration Day

This Saturday we will be helping to celebrate the third World Fish Migration day. There will be a number of fascinating events and activities in Wales for people to enjoy and learn more about the life-cycle of migratory fish species.

This global initiative aims to highlight the importance of conserving migratory fish species and aquatic ecosystem. Approximately 50 countries will celebrate this inspiring day and more than 2,000 organisations are participating in the occasion, holding over 400 events ranging from dam removals and river clean-up activities to educational seminars and fishing events.

All around the world, people depend on fish for livelihoods, economic value and healthy ecosystems. But fish also depend on people, to be able to freely migrate and thrive. There are around 15,000 freshwater fish species known to migrate in some way during their life cycle including our wild salmon and sea trout. Around 1,100 of these are long-distance migratory fish that depend on free-flowing rivers to thrive, including the iconic European eel that migrates over 10,000 km between the Sargasso Sea and European.

Richard Garner Williams, National Officer for Salmon & Trout Conservation Cymru said:

“We are supporting this important initiative because it is vital that we raise awareness about the need to improve and restore our watery environments for migratory fish.

Rivers provide many services for us including water supply, hydropower, and irrigation but often these activities are carried out at high cost to the environment and migratory fish species. We would therefore urge people to attend some of the local events that are being organised in Wales as part of World Fish Migration Day. These will help all ages learn more about our rivers and importantly how we can make these safe havens for our very special fish species.”

Events being held across Wales on Saturday 21stApril for World Fish Migration Day include: 

  1. Super Sewin Saturday. Whitland Memorial Hall, Whitland, Carmarthenshire. S&TC Cymru, The West Wales Rivers Trust and natural Resources Wales. Open from: 11:00 – 14:00. Free admission. Presentations by : Dr Graeme Harris (renowned sea trout expert) - “ Welsh Sea Trout: recent developments and new questions” Dave Mee (Senior Adviser Fisheries, NRW) – “Science and the Sewin” Richard Garner Williams (S&TC Cymru) – “The Meaning of Sewin” Helen Jobson and Lloyd Williams (WWRT) – Riverfly Demonstration

Contact Richard Garner Williams    e. wales@salmon-trout.org   m. 078 0905 6152

  1. “Radyr Weir Fish Migration Day”Radyr Weir, Cardiff : South East Wales Rivers Trust, Natural Resources Wales, Cardiff Harbour Authority, Cardiff Council and Dwr Cymru Welsh Water from 10am-3pm. Entry is free, so bring the whole family along and join us for face painting, fun competitions and art and craft activities.  Pictures of work the Trust and others have carried out to improve fish migration on the River Taff, and in other areas, will be on display, along with a sample of river life. There will also be talks by organisations about their work in and along the Taff that has helped to transform a river, once blighted by industry, into one that is recognised far and wide for its fish populations, as well as wildlife.

Contact Tony Rees m. 07702435021    t. 01685723520  e. tony.rees@sewrt.org

  1. Journey with a fish up the River DeeChester Weir, Chester, The Welsh Dee Rivers Trust, Natural Resources Wales and the North Wales Wildlife Trust.  Admission is free and it runs from 11:00 – 14:00 pm
  2. Exploring the Afon Einig. Wye & Usk Fundation. The Wye and Usk Foundation’s event is at their HQ on The Square, Talgarth, Brecon LD3 0BW where they will be exploring the current status and hopes for the restoration of the Afon Ennig, a once prolific spawning ground for Wye salmon
  3. Swansea University Family Day.  This is a family day allowing families to learn about the research going on at Swansea. One of the activities will be a game illustrating the challenges faced by fish migrating downstream towards the sea. This activity will be run twice during the day so that as many attendees as possible can engage with it. Location: The Wallace Building, Singleton Park SA2 8PP

For more information on these events or World Fish Migration Day, please contact: Richard Garner Williams on email: wales@salmon-trout.org or m. 078 0905 6152 or visit the website for World Fish Migration Day at https://www.worldfishmigrationday.com