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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

Sediment continuity through small scale run-of-river hydro schemes

A review of the extent to which deposition and accumulation of sediment behind the weir of hydro schemes impact fluvial dynamics, habitats and species, both on single developments and cumulatively within catchments, and what mitigation can be implemented to counter any impacts.

There are currently over 530 feed-in-tariff (<5 MW) scale hydro-electric schemes installed across Scotland, with a further c.30 in planning, consented (awaiting construction), or under construction.  The majority of installed small scale schemes are run-of-river designs consisting of a weir and screened offtake. SEPA guidance for developers of run-of-river hydropower schemes requests that proposals are assessed against particular criteria to ensure they comply with Water Environment (Controlled Activities) (Scotland) Regulations 2011 (CAR). One of the criteria covers the management of sediment accumulating upstream of the weir. SEPA, and SNH in their guidance on assessing impacts from hydro schemes on the natural heritage, clearly identify sediment accumulation and associated impacts as an issue to be considered in the Environment Impact Assessment (EIA), and CAR and planning applications.

Currently, there are many schemes where there is provision in the CAR licence for sediment management as suggested but no requirement, and few hydro schemes have been developed with an associated sediment management plan specifically aimed at maintaining natural sediment transport. A particularly problematic issue is the relative rates of transport and accumulation of fine and coarse sediment. Fine sediment is transported and accumulates more frequently. The result can often be an overload of fine sediment in the downstream channel when management is carried out.

The overall aim of this project is to enhance our understanding of what can be done to mitigate or prevent the impacts to the water environment and surrounding natural heritage associated with the accumulation of fine and coarse sediment behind run-of-river hydro scheme weirs, both now and in response to different climate change scenarios and the impacts these could have on fluxes of water and sediment supply and transport. 

This project will focus on identifying the most appropriate suite of sediment management techniques for use in Scotland, based on a review of existing techniques, the possible identification of new techniques, and a cost-benefit analysis of these techniques.  

Project Objectives

Research questions to be answered through this project:

Taking into consideration fluxes of water and sediment both now and in response to future climate change scenarios:

- What preventative and mitigation measures could be used to counter the impacts of sediment accumulation behind the weir of run-of river hydro schemes on fluvial dynamics, habitats and species?

- Are there measures that could address both the impacts of single developments and the cumulative impacts of multiple developments within catchments?

Contact Nikki Dodd
17th December 2020

Natural sources of phenols and mitigation measures to reduce their release into the water environment

This study investigated the current state of knowledge reported in the literature on the sources of natural phenolic compounds; factors that trigger their release into the environment; their risks to water sources and potential mitigation measures to reduce these risks. A potential risk assessment methodology, which assesses the terrestrial sources of phenolic compounds and the potential risk to ground and surface waters was presented. 

The main findings and recommendations from this study are: 

  • Changes in observed DOC concentrations may be used as an indicator of potential changes in the presence of phenolic compounds in surface and groundwaters.
  • Restoring peatlands is one of the key factors of locking carbon in the soil and reducing the release of DOC and phenolic compounds to water sources.
  • There are very few studies on the presence of phenolic compounds in the environment released from natural sources and their subsequent transfer to watercourses. A recommendation from this work would be to carry out a long-term study of the types of DOC and phenolic compounds in Scottish drinking water catchments. This would provide up to date data to validate the risk assessment developed in this project, and also to better understand the potential drivers of the release of phenolic compounds and their transfer in Scottish drinking water catchments.
10th December 2020

Digital Water: Technologies in Monitoring, Surveillance, and Evaluation

On the 11 November 2020, CREW hosted a webinar that brought together academics from the James Hutton Institute (Hutton) and the University of Stirling (UoS). The teams discussed how the digital revolution is transforming water research and how, with transformation, comes tremendous opportunities for the water industry, regulators and practitioners. In a series of 5 minute spark talks the research teams shared exciting developments in digital water research.
Initial  discussions also touched on:
Which Scottish (& wider) research teams are leading the Digital Water’ space?
How to enable future collaborations between organisations?
How to use our expertise to address wicked water-related challenges in the future?
The importance of engaging the wider stakeholder community through research to realise impact.
Horizon scanning (Funding opportunities).
Open the PDF document below for more information and links to video recordings.
2nd December 2020

CREW Newsletter Nov 2020

Check out our newly designed and re-launched Newsletter with updates on our recent activities, highlights and publications.

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