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4th May 2021

Review of wastewater monitoring applications for public health and novel aspects of environmental quality

Review of wastewater monitoring applications for public health and novel aspects of environmental quality

Wastewater-based epidemiology (WBE) has received increasing attention over the past year across the world. In the UK, local, regional and national wastewater monitoring programmes were established in 2020 to detect severe acute respiratory syndrome coronavirus (SARS-CoVID-2) patterns in human sewage to monitor outbreaks. The establishment of these monitoring programmes has seen considerable investment into establishing the infrastructure, methodology and resources needed to sample, analyse, and interpret data from WBE. Whilst coronavirus has so far been the primary focus of these programmes, it is widely acknowledged that wastewater contains a diverse amount of chemical and biological information that can be used for wider public health purposes. The aim of this project was to review the literature on where else WBE could be utilised to inform public health.   

The key findings indicate that there are only a very few technology ready applications of WBE. These include: (1) Estimation of community wide illicit drug usage; (2) Estimation of lifestyle chemical usage: alcohol, nicotine and caffeine; (3) Infectious disease tracking (e.g. polio, SARS-CoV-2); (4) Estimation of disease prevalence based on pharmaceutical usage. 

The forementioned applications require significant infrastructure, including specialised staff to undertake sampling and sample preparation as well as an investment in analytical instrumentation. There is a clear potential to apply WBE in:

  1. Estimation of community-wide exposure to hazardous chemicals. Some initial work indicates that wastewater can provide information on community wide exposure to pesticides and industrial chemicals, which are linked with either occupational exposure or lifestyle choices. 
  2. Prevalence of non-communicable disease (NCD). Current WBE approaches allow for estimation of pharmaceutical usage to treat, e.g. diabetics, cardiovascular disease or mental health conditions.   
22nd March 2021

WaterWall in Motion

WaterWall competition
Working in partnership with the Scottish water community, CREW has developed the WaterWall in Motion – a project that promises to be a fantastic video resource and competition to celebrate Scotland’s relationship with water, and its Hydro Nation ambition. The aim is to celebrate how Scotland is leading the way in water research, innovation, management, business, creativity, health, art and recreation.

WaterWall in Motion

Working in partnership with the Scottish water community, CREW has developed the WaterWall in Motion – a project that promises to be a fantastic video resource and competition to celebrate Scotland’s relationship with water, and its Hydro Nation ambition. The aim is to celebrate how Scotland is leading the way in water research, innovation, management, business, creativity, health, art and recreation.

The project is open to the public and any organisation, business or individual working to monitor, research, innovate, manage, regulate, conserve or simply enjoy and value Scotland’s water resources. The existing WaterWall, developed at the James Hutton Institute, has been enhanced to accommodate videos and the water community is invited to post links to 2-minute videos on one of eight themes


·       Nature-based solutions

·       Droughts and floods

·       Water quality

·       Living with climate change

·       Freshwater restoration

·       Innovation in the water sector

·       Water and wellbeing

·       Water inspired creativity


Prizes will be awarded across categories for innovation, creativity, originality; actions for achieving net zero carbon emissions and most impactful (evocative, celebratory or inspirational video).

This project aims to showcase and raise the profile of Scotland as the Hydro Nation at COP26 and satellite events, as well as to provide a point of reference for the water community to aid in the development of new networks and opportunities in the water sector. The WaterWall in Motion project was launched at World Water Day 2021 on the 22nd of March and the competition will run until the 13th August 2021.  

Please click on the WaterWall poster pdf below to access information on how to create and upload your video.


22nd March 2021

We must start to truly value water

Glasgow River Clyde
On the 22nd of March, Scotland celebrated World Water Day 2021, as part of a global UN initiative to understand the value of water to us all. But define value – it’s very subjective. Water, though, is so fundamental to all our existence it inherently draws together many perspectives on value, and these evolve as we know more about our most precious of resources.

Making up 70% of our world, it’s what justifies us as the Blue Planet, spinning in space. Without it there would be no life. It is the lifeblood of industry: 90% of the global economy and 75% of jobs depend on water to some extent. But it is in crisis through our accelerating lifestyles and attendant demands on its use and overuse, and also because of climate change. Indeed, in many ways it is the messenger of climate change - ninety percent of all natural disasters are water related and these increasingly impact on more and more people across the globe. In short, it’s time to change our relationship with water.

In a water-rich country like Scotland we tend to take it for granted. Turn on the tap and it’s there, aim to go for a walk and bucket loads fall from the sky. It’s beloved of taxi drivers nationwide. But that’s not true across the globe. The arrival of rain is cherished and welcomed in some countries and in others the overuse of a once abundant resource is placing increasing constraints on livelihoods and the escape from poverty. The quantity of water has not changed, indeed that has not changed since dinosaurs roamed the world, but that water is finite and under threat. In many situations it is the quality of water and its distribution in time and space that are the problem: too much here; too little there. It’s not a level playing field, and demand for water keeps rising as society’s demands grow and cities develop.

And not all water is equal. We have blue water in our rivers and lakes, green water being drawn up to support plant and crop growth, grey, brown and black water in our waste-streams. We drink tap water, mineral water, sparking water, well-water, distilled water and product manufacturers probably aim to market even more subtle “types of water”. It can come from different sources: raw water from the hills, brackish water, groundwater, rainwater or wastewater. But basically, it is still just H2O.

So why is this important? Simply because we depend for our survival on these different types of water that we put to different uses and all of which have different values. But again; define value. To many it’s the simple pounds, shillings, and pence of the water market. What does it cost to make it fit to drink or use and what does it cost to clean it up afterwards? Water, though, has value that transcends money. It has spiritual or religious significance. It has value for mental wellbeing; the mindfulness of hearing the patter of water on a roof, trickling in a burn or waves lapping on a beach; the moods of rainfall, rainbows and cascades; the feel of it on our skin. What value do we place on those attributes, and how do we assess them against the hard economic costs? That’s the challenge.

Our waste streams, historically the polluter of many of our country’s beautiful rivers are now highly valued for their embedded nutrients, metals and energy, all of which can be recovered and reused. Scottish Water has a new, world-leading target of attaining net-zero by 2040. Our new approaches to protecting cities from floods based on wider ecologically-based measures provide value not only in their primary function, but also because they provide prized ‘blue-green’ recreational spaces, important corridors for wildlife and settings for desirable and usually expensive real estate.

Our relationship with water is changing and must continue to change. Truly valuing water means giving it appropriate recognition, promoting efficiency and balancing short-term need against longer-term sustainability. Thinking about our legacy to others.

This article was written by Prof. Bob Ferrier, Director of CREW and the Hydro Nation International Centre (HNIC) and was originally published in the Scotsman.

5th March 2021

Lags in water quality response to diffuse pollution control measures: a review

Lags in water quality response to diffuse pollution control measures: a review

A systematic review of evidence on lags in water quality response to diffuse pollution control measures implemented in Scotland is reported. The review focused on key pollutants in catchments smaller than 300 km2 in temperate regions. Findings were evaluated based on catchment typologies (e.g. catchment size, precipitation, land use, pollutant residence time, and soil /waterbody type) and data/analyses (e.g. monitoring design and record length). There was no evidence supporting fixed timeframes for a water quality response to measures or catchment typology -based lags. Observed lags varied: 1-25 years for river pollutants and potentially longer than 20 years for groundwater nitrate. Long-term water quality and catchment data are key to quantifying lags. It is recommended to keep monitoring and adjust expectations by planning for longer-term lags.


16th February 2021

Pharmaceuticals in the water environment: baseline assessment and recommendations

Data from a range of sources including published and grey literature, internal company and regulatory datasets were examined. Researchers at other Scottish Higher Education Institutes and the James Hutton Institute were also approached directly to provide relevant data. Mean concentrations for each monitored location were assessed against threshold values for environmental (ecotoxicological) risk and, for antibiotics, against threshold values above which the substance might act a driver for antimicrobial resistance (AMR). About half of all surface water data pertained to samples targeting high-risk settings, such as immediately downstream from a wastewater treatment works rather than ‘typical’ environmental concentrations in the water body. This enabled a worst case baseline position to be established.

Application of drinking water treatment sludges to land: opportunities and implications

Investigating the feasibility of future application of drinking water treatment sludges to land 

This project will review the circumstances and locations where application of drinking water treatment sludges to land have been carried out to date (primarily in the UK and Europe) and review management practices used in the application of drinking water treatment sludges. 

The project will investigate if lessons can be learnt and implications of applying drinking water treatment sludges to land can be understood, particularly with regards to benefits and disbenefits in, and the impact on, phosphorus retention, and in the wider context of addressing Circular Economy goals i.e. working towards ensuring finite nutrients are recycled and waste materials and by-products are used sustainably.

Project Objectives

Research questions to be considered through the project:  

- What are the benefits and disbenefits of applying drinking water treatment sludges to land?

- How does this fit in the context of the circular economy in Scotland?

- What is best practice in terms of application? What information (e.g. which (chemical) analyses of sludge and soil) is required to allow a proper assessment of the suitability for application to land?

- Which measures could (help to) mitigate the disbenefits?

Contact Nikki Dodd

Moderating extremes in water availability in Scotland: a review of the role of functioning peatlands and wetlands

A review of available information on efficacy of peatland and wetlands in water management in a Scottish context.

Since 2012, over 19,000 hectares of peatlands in Scotland have been put on the road to recovery with funding provided by the Scottish Government. Communication of the benefits has primarily focused on carbon storage and sequestration, and biodiversity in terms of how peatlands and wetlands are functioning ecologically.  There is an additional need to quantify and communicate benefits based on water management.

Biodiversity is integral to the functioning of peatlands and wetlands, and functioning, well-managed peatlands and wetlands modify hydrological extremes and water availability.  However, much of our peatland and wetland is in poor condition and requires suitable management and in many cases restoration. With climate scenarios predicting that Scotland will experience increased temperature and changing rainfall patterns, including more frequent and more severe droughts due to climate change, it is anticipated that in the coming decades the main conditions needed for peat formation– primarily waterlogging and cool temperatures – may not be met at all current peatland sites in Scotland.

There is an urgent need to consider how biodiversity and primary water supply mechanisms for different peatland and wetland types may be affected by  flooding or water scarcity, current and potential future changes in land use and water use in response to changing climate and societal demands on valuable land and water resources.  In addition, best practices and future options for water and land management activities and plans – including drought plans – for peatlands and wetlands need to be discussed with a wide audience to inform future joint actions and approaches.


Project Objectives

Research questions to be considered in this project: 

- How do a broad range of wetlands in Scotland buffer extremes of water availability, focusing on both low and high flows?

- What are the mechanisms for this and their relative importance?

- How is this buffering capability compromised when wetlands are degraded due to land use conversion or climate change?

- What are the impacts, caused by extremes of water availability, on the biodiversity of Scottish wetlands?

- Are there opportunities or potential changes in land or water management, which could enhance this buffering capability of wetlands in Scotland?

Contact Nikki Dodd

Scoping the development of a model to estimate phosphorus (P) loads to water from septic tanks

Under the requirements of the Water Framework Directive, there is a need for SEPA to identify pressures contributing to water quality downgrades and to put in place appropriate and feasible measures to return waters to good status.

Septic tanks are private sewage treatment facilities which typically serve the population not connected to main sewer networks. There is substantial uncertainty about the impact of septic tanks on water quality, primarily because of a lack of information about the location, number and condition and inadequate monitoring of the effects of septic tank discharges to surface water and groundwater.  

SEPA currently use the SAGIS model to identify major pollutants including phosphorus (P) loads and concentrations at the waterbody scale. A number of assumptions are currently made regarding the parameterisation of the SAGIS model including input loads and connectivity to surface water to generate export loads from septic tanks.  A new approach to modelling the contribution of P is required to inform the development of specific strategies or implementation of measures for mitigative purposes.  

This study will identify a method and data requirements for a model to estimate soluble reactive phosphorus (SRP) losses to water from STS, initially for a number of pilot catchments and then at a national scale. 

Project Objectives

Research questions to be answered through this project: 

- What factors contribute to the risk of phosphorus (P) pollution from septic tank systems (STS)?

- Can a probabilistic risk model informed by expert knowledge be applied on a national scale, given available data?

- What factors would need to be considered to apply the model to nitrogen (N) and microbial (FIOs) pollution risk?


Contact Nikki Dodd

Estimating environmental response times to implemented measures based on catchment typologies

SEPA implement regulatory and incentivised measures to protect and improve water quality. The intended effects of the various measures implemented are to: (i) avoid or reduce inputs of pollutants at source; (ii) control / delay transport of pollutants in-field; and (iii) trap pollutants before they reach waterbodies. Estimating lags in water quality response to measures based on catchment typologies could help SEPA to improve diffuse pollution control and communicate to stakeholders the causes of the perceived lack of response to measures in waterbodies that have not improved yet.

This project will undertake a systematic review of the literature on water quality response and lags in response to the measures implemented.

Project Objectives

Research questions to be answered in the project: 

  1. What key catchment processes influence lags in water quality response to diffuse pollution control measures (hereafter the measures)?
  2. What (inter)national evidence base is available on lags in water quality response to measures for each type of measure and pollutant, i.e. total phosphorus (P), soluble reactive inorganic phosphorus (SRP), total nitrogen (TN), nitrate, faecal indicator organisms (FIO), and sediment?
  3. Is it possible to define/identify catchment typologies in Scotland to estimate lags in water quality response for each pollutant and type of measure? If not, why not?




Contact Nikki Dodd

Effectiveness of construction mitigation measures to avoid or minimise impact to groundwater dependent wetlands and to peat hydrology

A review of evidence of the effects on groundwater and habitats of standard mitigation measures, used during construction, intended to mitigate effects on hydrological regime of groundwater dependent wetlands and peatlands

The EU Water Framework Directive (WFD) and the Water Environment and Water Services (Scotland) Act promote long-term sustainable water management and aim for good ecological status of surface and groundwater bodies.  Wetlands that critically depend upon groundwater are important ecosystems.  They can support biodiverse communities and they reflect the ecological quality of the groundwater bodies on which they depend.  With increasing population pressures, societal demands for renewable energy, housing and a drive to repopulate rural areas in Scotland, there has been increased construction on peatlands and wetlands.

The WFD and the Groundwater Directive place a duty on responsible authorities to protect Groundwater Dependent Terrestrial Ecosystems (GWDTE) from damage for example, caused by pollution and abstraction or diversion of groundwater flows. Mitigation measures are put in place during construction to avoid or minimise impact to groundwater dependent wetlands and to peat hydrology, however many measures are being used without clear information on their effectiveness. 

This project will review literature and trial data to evaluate how effective standard methods used during construction to mitigate impacts on the hydrology and habitats of groundwater dependent wetlands are to inform guidance provided to developers and knowledge around appropriate compensatory habitat creation/restoration.

Project Objectives

Research question to be answered through this project:

How effective are standard methods used during construction to mitigate impacts on hydrology which may affect groundwater dependent wetlands and peat?

Contact Nikki Dodd


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