The Oxford Rivers Portal, a website and map that aims to help people understand the health of the Thames and its tributaries in Oxfordshire and make informed choices about safer river conditions, has been launched today (9 September) by environmental charities the Rivers Trust and Thames21 and research institute the UK Centre for Ecology & Hydrology (UKCEH).

The launch of the Oxford Rivers Portal follows increasing public concern over the state of England’s rivers, as well as a growth in interest in wild swimming and watersports.

On a single map, it brings together live raw sewage spill alerts, water quality measurements taken by the Environment Agency and citizen scientists, water levels, flood warnings, bacteria measurements at bathing water sites and sewage treatment rates* at both Oxfordshire’s designated bathing waters, Port Meadow in Oxford and Wallingford Beach. Users can zoom in and click on any of more than 2,000 locations to find out real-time information or data from the past three years.

Previously, these varied data sources were available on different websites and were difficult to access.

Claire Robertson, Oxford Rivers Project Officer at Thames21, said: “Water quality and the health of rivers must improve. The main sources of pollution are agriculture and the water industry, plus a growing threat from plastics and forever chemicals. As more people look to England’s rivers for recreation, we all need to up our game.

“We hope this portal makes it easier for people to decide whether they want to swim, or take out their canoe or paddleboard, on a certain day or not.

“River swimming is so good for you if you do it safely: don’t go into water you can’t swim against, don’t jump into water where you don’t know what’s underneath, and wash your hands after swimming.”

Dr Virginie Keller, an environmental modeler at UKCEH, added: “River pollution is now a major issue of concern for many people but it’s difficult to get clear, up-to-date information about water quality and conditions locally. Our portal is a ‘one-stop shop’, bringing together a variety of data in an accessible way.”

The development of the Oxford Rivers Portal is part of the European GOVAQUA project which aims to accelerate a transition towards sustainable and equitable water use by better water governance. It is funded by the European Union and UK Research and Innovation.

The team behind the portal says the data and information will enable users to gather evidence to understand the state of their local water courses and thus stimulate discussions between the public, regulators and water companies about policies and management relating to rivers and streams.

As designated bathing sites, Port Meadow in Oxford and Wallingford Beach are tested weekly for potentially harmful bacteria by the Environment Agency between mid-May and the end of September. Apart from one day at Wallingford, all the bacteria readings at these two sites have been below the level of concern this season.

Analysis of data from 2023 has found that five out of the seven local sewage treatment works for which data has been provided, show indications of illegal “early” spills of raw sewage.

Sewage treatment works must reach a minimum flow level (called “flow to full treatment”, or FFT) before they can legally discharge raw sewage to rivers and streams via storm overflows, to prevent it backing up in the system. The works are meant to be operating at this minimum level for between one and four hours before a raw sewage release is permitted.

However, on 183 occasions, treatment works had not met this minimum flow rate in the past 24 hours before a raw sewage discharge occurred. Oxford sewage treatment works had 77 separate “early spills” totalling 1,839 hours, Appleford works had 89 spills totalling 1,692 hours, and Stanton Harcourt works had seven early spills totalling 1,322 hours.

*Sewage treatment rates show the rate of sewage treatment at a sewage treatment plant in litres per second. Users of the portal can use this data to find out if a sewage treatment plant is operating at full capacity or operating at low capacity.

International research team say they have identified more than 120 organic micropollutants and investigated their role in damaging aquatic organisms

Tonnes of dead fish, mussels and snails were seen floating on the River Oder (Germany) in early August 2022. It soon became clear what was causing the environmental disaster in the German-Polish border river: a mixture of excessive salinity, high water temperatures, low water levels and excessive inputs of nutrients and wastewater triggered a bloom of the brackish water algae Prymnesium parvum, whose algal toxin prymnesin has a lethal effect on organisms. A team of scientists coordinated by the Helmholtz Centre for Environmental Research (UFZ) collected and analysed water samples at the time. The result, published in Nature Water today (6 September), appeared to show that high concentrations of organic micropollutants exacerbated the lethal effects of prymnesin.

Summer 2022’s environmental disaster led to the death of up to 60 per cent of fish biomass and up to 85 per cent of mussel and snail biomass in the River Oder. In August 2022, the UFZ set up an interdisciplinary ad hoc working group together with researchers from the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB), the University of Veterinary Medicine, Vienna (Vetmeduni) and the University of Birmingham. They took water samples at five locations along the Oder, extracted poisoned fish and analysed and evaluated the samples. “The aim of the study was to find out which micropollutants are in the Oder, how they affect aquatic organisms in the river and what threat the cocktail of algal toxins and micropollutants could pose to humans,” says Prof Dr Beate Escher, lead author and environmental toxicologist at the UFZ.

As the researchers now explain in the scientific journal Nature Water, they were able to detect more than 120 organic micropollutants in the water samples. The highest concentrations of chemical substances were found for the flame retardant tris(1-chloro-2-propyl)phosphate, the polymer additive hexamethoxymethylmelamine and the corrosion inhibitor 1H-benzotriazole. Most of the pollutants detected were presumably discharged into the Oder from sewage treatment plants, but their concentrations were low. However, the scientific team also found pollutants such as 2,4-dichlorophenol, which were probably discharged from industry, as well as pesticides and their degradation products, such as chlorotoluron, which were discharged directly into the water from agricultural land. “The concentrations of these chemicals are not unusually high, but are typical for European rivers”, says Beate Escher. “They did not lead to fish mortality, but together with the algal toxins they can lead to additional stress for aquatic organisms.”

The researchers used the risk quotient RQ to analyse the extent of this stress and thus the risk of the detected pollutants for aquatic organisms. The RQ is defined as the ratio between the measured concentration of a pollutant and its predicted no effect concentration (PNEC). If the RQ exceeds the value of 1, the pollutant can affect aquatic life. The researchers added up the RQs of the detected chemicals and thus obtained mixture risk quotients (RQmix) of between 16 and 22 at the sampling sites. “All RQmix values significantly exceeded the threshold value of 1, which indicates a potential risk to aquatic organisms from pollutants,” says co-author and water chemist Dr Stephanie Spahr from IGB. Only 30 organic micropollutants were included in the model, although thousands of organic chemicals are probably present in the river. The chemical cocktails extracted from the water samples also showed clear effects in laboratory experiments with algae, water fleas and zebrafish embryos, which are considered common models for aquatic organisms.

The researchers investigated how these pollutants and the prymnesins found in the Oder interact as mixtures in water extracts using neurotoxic effects on human nerve cells in vitro. “This test, which is commonly used in bioanalysis and water quality assessment, does not aim to assess the risk to human health, but rather to identify the mixture effects of neurotoxic chemicals,” says Beate Escher. Assistant Professor Dr Elisabeth Varga, a food and environmental analyst at VetMedUni Vienna, provided an algal toxin standard that is very similar to the prymnesins identified in the Oder. The in vitro assays are carried out at the UFZ in automated high-throughput screening in the modern CITEPro[SH1] technology platform in very small volumes. “It was therefore possible to test this prymnesin standard and other detected micropollutants as well as the water extracts directly,” says Beate Escher. Even at very low concentrations in the nanomolar range, prymnesins shortened the outgrowths of nerve cells that are responsible for signal transmission and killed the cells.

In addition, many organic micropollutants quantified in the water extracts were analysed: several substances were neurotoxic, but at significantly higher doses. “Through mixture modelling and comparisons of the neurotoxicity measured in the extracts, we were able to show that prymnesins dominate the neurotoxic effect. However, the micropollutants we detected also contributed to this,” says Elisabeth Varga. However, the effects of pollution on aquatic organisms in rivers such as the Oder could ultimately be much greater. “The prymnesins have a very high proportion of the cocktail effects, which are exacerbated by micropollutants. This puts even more pressure on the entire ecosystem of the Oder, which is already under great stress,” says Beate Escher. And Prof Dr Luisa Orsini, co-author and Professor of Evolutionary Systems Biology and Environmental Omics at the University of Birmingham, adds: “The warmer temperatures and extreme weather events caused by climate change can make such toxic algal blooms an even greater risk for inland and marine waters and the population.”

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Sewage pollution in surface waters in the UK and Ireland is one of the most high-profile environmental issues in the country. Water industry research organisation UKWIR says it is leading a raft of innovative sewerage projects designed to transform the way water companies manage this issue in the coming five-year Asset Management Plan period for England and Wales – AMP8, which starts on 1 April 2025.

“UKWIR’s research programme aims to create a future where sewerage management is not just an essential service, but a key contributor towards a sustainable and healthy environment,” said Jenni Hughes, UKWIR strategic programme manager.

“Previously, UKWIR research has focused on getting a deeper understanding of the networks, because we need to understand what’s happening in the existing network before we can make meaningful, long-term improvements.

“Now our focus shifts to the future, with societal needs, environmental protection and resilient infrastructure at the centre. The latest wave of research offers water companies the tools and knowledge they need to navigate the ongoing challenges of sewage management into the next asset management period and beyond.”

Protecting rivers and seas
The impact of sewage and stormwater discharge, agricultural runoff, and urban pollution on river ecosystems in the UK and Ireland is a key area of research for UKWIR.

Dr Nick Mills is UKWIR’s programme lead on the organisation’s Big Question 6: How do we achieve sustainable and resilient sewerage and drainage by 2050? He is also director of environment & innovation at Southern Water.

Mills says, “To optimise the benefits for both people and nature, we need a data-driven river strategy that comprehensively analyses threats to river health. This approach should hold all sectors accountable, while simultaneously empowering them to identify solutions for building and maintaining healthy rivers.

“There is a lot of focus on storm overflows in the media and from the general public. They are a legacy asset that the sector is attempting to phase out through a combination of nature-based and sustainable drainage systems, and data-driven engineering approaches.

“More widely, reducing storm overflows requires urgent, collaborative action from water companies, councils, property owners and the public,” added Mills.

Beating blockages
Sewer blockages are a major concern in the UK, with an estimated 200,000 occurring annually, and FOG – fats, oils and grease – cited as the cause in around 75% of cases. A build-up of FOG hinders the smooth operation of sewer systems and wastewater treatment works (WwTWs), shortens the lifespan of critical assets and increases maintenance costs.

This burden ultimately falls on water companies, which may be forced to raise prices for customers. Additionally, FOG blockages can cause sewer overflows, creating a public health hazard and impacting the environment.

UKWIR projects aiming to tackle this include:

• Understanding the scale and impact of privately owned drains and sewers on sewer capacity
• FOG charging – should food service wastewater charges reflect FOG content?
• Modelling sewer inlet capacity restrictions
• Treatment options for storm overflows

Nature as a stakeholder
Protecting and enhancing waters, and the wildlife and communities they support requires a combination of grey and green solutions. For water companies looking to create greater social value, nature-based solutions (NbS) such as sustainable drainage systems (SuDS) can offer a powerful and cost-effective approach.

However, there is currently limited sector-wide data on the benefits, reliability and cost-effectiveness, compared to traditional engineered and technological alternatives.To address this issue, UKWIR currently has a research project aimed at improving the understanding of the whole-life cost, carbon footprint and delivery of retrofit SuDS.

Data and insights
Water companies in the UK are being urged to be more transparent with the public about sewage spill data by the information commissioner.

The use of data-driven methods, including artificial intelligence and predictive analytics, is a promising approach to proactively identify and address blockages in sewer systems, ultimately improving environmental protection, public health and compliance with regulations.

Recent UKWIR projects include:
· Modelling sewer inlet capacity restrictions
· Quantifying, managing and communicating the differences in storm overflow spill data between event duration modelling (EDM) outputs and hydraulic model prediction

Working with customers
Customer behaviour can also play a significant role in reducing the amount of sewage entering watercourses in the UK.

Customer-caused blockages in sewers are a major issue in the UK. Every year in England and Wales, water companies spend millions of pounds dealing with over 300,000 blockages – thousands of which see people’s homes and belongings ruined by sewer flooding.

A recently published UKWIR project – Learning and recommendations from customer behaviour campaigns on blockage reduction – highlights the need for effective customer campaigns to reduce blockages, and emphasises the importance of tailored campaigns, a unified national approach, and collaboration among water companies via a proposed national working group focused on changing customer behaviour regarding blockages.

UKWIR has announced the direction of travel for research projects from now to 2050. The refreshed strategy aims to bring together global trends in water management with impactful research to address UK-specific industry challenges identified through the UKWIR Big Questions and extensive stakeholder engagement.

For more information, visit: ukwir.org/ukwir-announce-new-research-strategy

India’s plans to scale up fracking operations without robust regulations could spell disaster for the country’s finely balanced water security, according to research from the University of Surrey. 

India is positioning shale gas as a key transitional energy source and has announced 56 fracking projects across six states. Despite the promise of energy independence, the new study appears to raise alarm bells about the country’s preparedness to handle the unique water risks posed by fracking. 

Hydraulic fracturing, or fracking, involves injecting high-pressure fluid into shale rock to release natural gas. This process has been controversial worldwide due to its significant environmental impacts, particularly on water resources. The study points out that India’s regulatory framework for fracking is currently based on rules designed for conventional drilling processes, which do not adequately address the distinct challenges fracking presents. 

More than 40 tonnes of bee-harming neonicotinoid insecticides, known as neonics, have been estimated to be flowing through Asia’s longest river every year, according to a new study published by researchers in Scotland and China.

The study, led by a specialist at The James Hutton Institute, alongside scientists at Northeast Agricultural University, Harbin, and Wuhan University of Technology, Wuhan, China, tested a 200 km-long mid-section of the Yangtze River for concentrations of 11 different neonics at 18 locations.

A third of samples collected contained levels of the insecticide that exceeded “chronic ecological risks thresholds”, while agricultural use identified as the main source. The most common neonic found was imidacloprid, of which China produced 23,000 tonnes in 2016, says the study authors.

Based on the chemical concentrations found, which would have come from the section tested, but also upstream of it and associated tributaries, the study estimated that 40 tonnes of the 11 neonics were flowing through the river annually.

Professor Zulin Zhang, senior research scientist at the Hutton and main-author of the study, says, “The findings from this study indicate a need for a better understanding both of the risks these chemicals pose to the environment and what we can do to make sure they do not undermine the health of the Yangtze River Basin, the world’s third longest river, which supports more than a third of China’s population (>400 million people).”

Neonicotinoids were developed in the 1980s and gained widespread use at a global scale. However, a number of countries have banned them, including the EU, which banned outdoor use of the three main neonics, including imidacloprid.

Other countries, including Sweden, the USA, Canada and the Netherlands, also have water quality guidelines for neonicotinoids with limits on concentrations.

There is also work ongoing to develop alternatives, which pose less risk, to the environment, as well as sustainable Clean-up technologies for emerging contaminants (for example, adsorption and advanced oxidation processes) are being potentially developed to remove these chemicals from waters once they enter the aquatic environment, adds Professor Zhang.

A landmark Supreme Court judgment on 2 July could open up new legal avenues for water companies to be sued for sewage dumping incidents.

The ruling, described as a “sensational victory” by campaigners, follows a hearing in March 2023 in which United Utilities said the canal’s owners, the Manchester Ship Canal Company, were not entitled to seek damages for the release of untreated water into its extent, citing the 1991 Water Industry Act, which seemed to specify that only regulators can seek this kind of action.¹

As not-for-profit Good Law Project explained,  the Environmental Law Foundation (ELF), backed by Good Law Project and represented by Hausfeld, brought an intervention in the hearing.²

Through ELF’s intervention it was demonstrated that sewage pollution was a significant problem for river and marine communities across the country and not just the Manchester Ship Canal. The judgment sets a significant precedent that has implications far beyond the Manchester Ship Canal.

The judgment overturned two previous rulings in the High Court and Court of Appeal in favour of United Utilities, who brought legal action against the Manchester Ship Canal Company in 2018.

Good Law Project said these previous rulings shielded United Utilities and other water companies against legal challenges from individuals and businesses affected by sewage discharges.

Figures published by the Environment Agency show that United Utilities has been one of the worst offending water company for sewage dumping since 2020. Last year the company discharged untreated sewage 97,500 times for a duration of over 650,000 hours.

Good Law Project’s interim head of legal, Jennine Walker, said:

“This is a sensational victory and a real boost to the clean up of our rivers, waterways and seas. It gives people stronger legal tools to turn the tide on the sewage scandal and hold water companies to account, after our toothless and underfunded regulators have failed to do so.

“We hope this landmark ruling empowers people and businesses to use the courts to challenge industrial-scale polluters like United Utilities, who have put profits and the shareholder interest over protecting our environment”.

Environmental Law Foundation co-director and casework manager, Emma Montlake, said:

“This was a ‘monster case’ as characterised by lead Counsel for the Manchester Ship Canal. Enormously complex, the outcome has the potential to be a game changer for communities up and down the land.

“Our water environments have been regularly polluted with untreated sewage, water biodiversity denuded and degraded with impunity by private water companies. A national scandal doesn’t come close to describing what we have put up with. This is a glad day for environmental justice, not just for the public, but for nature.”

Notes
[1] https://www.ft.com/content/9e7e840e-6d16-47ee-8ac1-9586a3de1495
[2] “Water companies could face raft of legal challenges after landmark sewage ruling”. From Good Law Project press office, Tuesday 2 July 2024.

In an article published in Nature Sustainability, researchers warn that discharges to the environment during drug production, use and disposal have resulted in ecosystems around the globe being polluted with mixtures of pharmaceuticals, posing a growing danger to wildlife and human health.

While emphasising that pharmaceuticals are indispensable in modern healthcare and will remain crucial in the future, the researchers highlight the need for designing and manufacturing more sustainable drugs to combat this issue at source.

“A wide variety of drugs have now been detected in environments spanning all continents on Earth,” said Assistant Professor Michael Bertram, a researcher at The Swedish University of Agricultural Sciences (SLU) and shared first author.

“Exposure to even trace concentrations of some of these drugs can have severe impacts on the health of wildlife and human populations, and has already led to severe population crashes in vultures throughout India and Pakistan, as well as widespread sex-reversal of fish populations exposed to the human contraceptive pill.”

Pharmaceutical pollution is a complex problem that demands a multifaceted solution. So far, environmental protection efforts have mainly been focused on upgrading wastewater treatment infrastructure to remove drugs before release into waterways more effectively.

Despite being an important part of an overall solution, wastewater treatment is unable to address this issue in isolation.

In the article, 17 leading international scientists call for an increased focus on designing greener and more sustainable pharmaceuticals to tackle this issue at its source.

“Because drug design is the first step in the life-cycle of pharmaceuticals, greener drugs reduce the potential for pollution throughout the entire cycle” said Gorka Orive, a scientist and professor of pharmacy based at the University of the Basque Country.

“Drugs need to be designed to not only be effective and safe, but also to have a reduced potential risk to wildlife and human health when present in the environment.”

Alarmingly, it is the very same characteristic of pharmaceuticals that makes them effective in human and animal patients that also makes them particularly hazardous environmental pollutants: drugs are specifically designed to have biological effects at low doses.

Pharmaceutical contamination of ecosystems is occurring alongside other widespread environmental changes, which can amplify the negative effects of drugs, including climate change and habitat destruction.

Pharmaceutical pollutants represent a particularly complex challenge given that many hundreds of different drugs have been detected in ecosystems globally that have an extremely wide range of effects, including anti-anxiety medications, antidepressants, antibiotics, and even illicit drugs such as cocaine and methamphetamine.

Charles Tyler, Professor of Environmental Biology and Ecotoxicology at the University of Exeter said: “Drugs in the environment has been an emerging issue for some time but now with evidenced cases for adverse effects in wildlife, together with a lack of data on the environmental risks for most drugs and marked increase in the use of many drug types, we need to better ensure that human medicines pose minimal threats to wildlife. Ensuring that ‘greener drugs by design’ features prominently in the drug development pipeline will help maximise environmental protection and in turn help to ensure the future sustainability of the drug industry and human medical healthcare.”

“We urge drug designers and manufacturers, scientists, and policy-makers to recognise the growing threat posed by pharmaceutical pollution, and to urgently prioritise the sustainable design of greener drugs in order to prevent further environmental harm,” said shared first author Professor Tomas Brodin at SLU.

‘The urgent need for designing greener drugs’ was published in Nature Sustainability in June.

London will need to urgently become a ‘sponge city’ – a city better designed to absorb and hold rainwater – in order to ward off the negative impacts of the climate emergency, the organisers of London Rivers Week have urged.

The climate emergency has increased the frequency and intensity of extreme weather events and governments, businesses and communities must protect London’s rivers in order for them to be better prepared to tackle the impacts of droughts and floods brought on by the climate crisis.

The organisers* of the London Rivers Week festival, which takes place this Saturday 22^nd June to Sunday 30^th June, are urging policymakers, water companies, businesses, industry, environmental charities and the public to work together on making the city ‘sponge like’. The festival celebrates London’s rivers and has a packed programme of walks, talks and online seminars for everyone to get involved in.

Environmental charity Thames21, one of the lead coordinators of London Rivers Week, is already working with partners and volunteers to make London a sponge city. It has created wetlands, planted trees and supported sustainable drainage systems across London to help improve biodiversity and capture rainwater to reduce flood risks.

For instance, its ‘Rewilding the Rom’ project in Dagenham has seen the development of a wetland that connected the River Rom to its floodplain and turned this river into a healthy environment for wildlife.

Chris Coode, CEO at Thames21, said: “London has lost many of its green spaces to urban development and we urgently need more nature-based solutions such as wetlands to help tackle the impact of the climate emergency. Wetlands absorb excess rainfall, slow down water flow to rivers and reduce the risk of flooding to homes.

“These green spaces are essential for managing surface water and creating environments where water is naturally controlled.

“Spending time by the river has proven benefits for people’s health and well-being. This is a key theme of this year’s London Rivers Week, now in its eight year. By transforming London into a sponge city we enhance our rivers’ resilience to climate change and ensure that we can all benefit from our precious rivers.”

Anna Taylor, director at CPRE London, added: “We are keen to highlight the urgent need for more rain gardens across the capital to reduce road-run off, ease the pressure on storm water drains, and help to reduce the risk of sewage overflow into our rivers. There is an absolutely urgent need for action in this area!  Sustainable urban drainage assessments should be bog standard when roadworks and streetscapes are being updated.”

Joe Pecorelli, ZSL’s Freshwater Conservation Programme Manager, said: “Protecting spaces for nature in London doesn’t just make the city a more enjoyable space – it’s key to creating a better, more sustainable future for everyone living here. From decision-makers to the general public, we need everyone to be involved in building a more resilient London, and attending walks and talks, or even donning a pair of waders to get stuck in with a clean-up, is a great place for people to get started.”

The source of pollutants in rivers and freshwater lakes can now be identified using a comprehensive new water quality analysis, according to scientists at the University of Cambridge and Trent University, Canada.

Microparticles from car tyres, pesticides from farmers’ fields, and toxins from harmful algal blooms are just some of the organic chemicals that can be detected using the new approach, which also indicates the impact these chemicals are likely to have in a particular river or lake.

Importantly, the approach can also point to the origin of specific organic matter dissolved in the water, because it has a distinct composition depending on its source.

It uses a technique called high-resolution mass spectrometry to analyse water samples: within an hour this provides a comprehensive overview of all the organic molecules present.

Water quality is strongly determined by the diversity of organic matter dissolved in it – termed ‘chemodiversity.’ The scientists say that the thousands of different dissolved organic compounds can keep freshwater ecosystems healthy, or contribute to their decline, depending on the mixture present.

The paper was published on 28 March in the journal Science.

“Traditional approaches to monitoring water quality involve taking lots of different measurements with many devices, which takes a lot of time. Our technique is a very simple way to get a comprehensive overview of what’s going on in a particular river or lake,” said Jérémy Fonvielle, a researcher in the University of Cambridge’s Department of Biochemistry and co-author of the paper.

To understand what drives this chemodiversity, the team reviewed studies of dissolved organic matter in freshwater samples from rivers and lakes across Europe and northern Canada.

For example, water analysis of Lake Erie in Canada revealed high levels of phosphorus pollution. By looking at the composition of individual molecules in the water sample, researchers identified agricultural activities as the source of this pollution, rather than wastewater effluent.

“Whereas before, we could measure the amount of organic nitrogen or phosphorus pollution in a river, we couldn’t really identify where pollution was coming from. With our new approach we can use the unique molecular fingerprint of different sources of pollution in freshwater to identify their source,” said Dr Andrew Tanentzap at Trent University School of the Environment, co-author of the report.

Traditional approaches involve separately measuring many indicators of ecosystem health, such as the level of organic nutrients or particular pollutants like nitrogen. These can indicate the condition of the water, but not why this state has arisen.

Dissolved organic matter is one of the most complex mixtures on Earth. It consists of thousands of individual molecules, each with their own unique properties. This matter influences many processes in rivers and lakes, including nutrient cycling, carbon storage, light absorption, and food web interactions – which together determine ecosystem function.

Sources of dissolved organic matter in freshwater include urban runoff, agricultural runoff, aerosols and wildfires.

“It’s possible to monitor the health of freshwater through the diversity of compounds that are present. Our approach can, and is, being rolled out across the UK,” said Tanentzap.

Fonvielle will now apply this technique to analysing water samples from farmland drainage ditches in the Fens, as part of a project run by the University of Cambridge’s Centre for Landscape Regeneration to understand freshwater health in this agricultural landscape.

Healthier rivers will be one outcome of implementation of the Environment Act 21, writes Darren Hanson of water technology firm Xylem. Now water companies need to concentrate efforts on ensuring a smooth rollout of monitoring technology.

The deadline is approaching for water companies to have in place monitoring requirements of the Environment Act 21. Part 5 Section 82 states utilities must continuously monitor water quality upstream and downstream of all storm overflow and sewage disposal works, which discharge into a watercourse. This requirement will be mandatory from April 2025

The new monitoring requirements will help utilities understand the impact of combined sewer overflows (CSOs) on the environment, including whether individual spills are mostly diluted by rainwater or pose a risk of pollution – and learn more about problem areas and where targeted investment is needed. Captured data can also support wider water management strategies and collaboration with stakeholders in the national effort to restore river quality.

To ensure the 2025 monitoring commitments are delivered, companies should now be taking the following steps:

• Identify which sites need to be monitored and which are priority sites to be addressed first, such as those within Sites of Special Scientific Interest (SSSIs), chalk streams and bathing waters.
• Engage with landowners for permission to install instrumentation and to return for ongoing maintenance and calibration visits. The majority of storm overflow sites sit on private land – access will be one of companies’ biggest challenges.
• Calculate how many monitors are required, bearing in mind current guidance states that where discharge outlets are within 1000m of one another, they can be clustered as a pair of monitors upstream and downstream.
• Establish the best locations for the sensors, remembering the aim of Section 82 is to monitor the impact on the receiving waters, not the discharge itself. Selected locations should be safely accessible. Where proposed sites do not have a power source, solar-powered systems are available.
• Attention should be given to risk of theft or vandalism in each location and vandal-resident systems selected, if required. The risk of theft of equipment such as solar panels and cables should not be underestimated and is an issue that has informed design of urban monitors.
• Begin conversations with suppliers to get a complete understanding of product options, delivery and installation timescales and cost. Given the impending increase in demand, early engagement is a must – suppliers like Xylem are increasing their manufacturing capacity and are ready to support.

Early monitor installation programmes already underway are shining a light on issues that may not have been considered, such as:

Data confidence
Water companies need confidence that the data they are receiving is accurate, repeatable and traceable. This is in part achieved by selecting technology appropriate for the local water environment.

What are the local fouling conditions, for example? If an individual sonde becomes covered with mud or algae, it may trigger a false water quality alert. Robust, anti-fouling technology, such as mechanical wipers, can prevent such data-uncertainty, as can ensuring sondes are calibrated for the conditions in which they are being used.

Invasive species strategy
Protection against invasive species should be part of implementation planning. As sensors move from one river to the next, there is a risk of invasive species transfer. Having a strategy around invasive species, including selecting instruments that can be cleaned before being calibrated, can help manage risk.

Data-as-a-service
More companies are now looking to data-as-a-service (DaaS) models to support with large-scale water quality monitoring. Applying DaaS can move responsibility for the design, installation, data, telemetry, calibration and maintenance to the manufacturer. HydroDaaS is Xylem’s DaaS system for river water quality monitoring and can support companies that may not have the infrastructure in place to manage a large network of sensors.

Monitoring technology is advancing fast, and Xylem’s researchers are continually updating smart systems with new algorithms and artificial intelligence which can alert on problems within the network.

The ultimate goal is to prevent CSO spills into receiving waters. To do this, we need a clearer understanding of what is causing spills to occur. Water quality monitoring provides one piece of the jigsaw. By combining this data with previously disparate datasets into a single platform, such as the Xylem Vue Powered by GoAigua (XVPGA) platform, a more holistic view at the catchment level can be attained.

Not only can this information help utilities identify failures within the catchment that lead to spills, it can also provide insights about assets which may lead to spills and allow preventative action to be undertaken.

Using digital platforms in this way enables utilities to optimise operations and make maximum use of existing infrastructure as part of a wider strategy to reduce environmental impact.

Looking at the bigger picture, the Environment Act 21 monitoring programme will eventually provide a national baseline of water quality information that England has never seen before. Its implementation is a major task, but the large-scale data capture soon to be underway will allow the water sector to digitise river catchments to provide a cleaner and heathier environment for all.

Darren Hanson will be joined by head of digital Ruth Clarke and director of engineering Rui Pina for a Xylem webinar exploring the Environment Act 21’s requirements, and strategies to measure, assess and reduce pollution. The webinar takes place on 24 April 2024. To register, https://xylem.zoom.us/webinar/register/6917102392517/WN_UsO4xvBcRXWN_70H_ysjzg#/registration