The importance of SuDS implementation and the challenges involved: expert opinions

Drainage systems are an essential part of any city’s water management. In particular, sustainable drainage systems (SuDS) have become increasingly important in water sensitive cities, as they have the ability to store and attenuate surface water, and the capability to treat runoff. The implementation of SuDS requires multiple areas, including planning frameworks, engineering designs, construction practices, maintenance processes, community buy-in and ownership agreement, working cohesively and aligning. 

To understand this alignment, as well as building an evidence base on the implementation and management of UK SuDS, STREAMer Peter Melville-Shreeve created a questionnaire to 50,000 industry professionals, which was distributed by the Chartered Institution of Water and Environmental Management. The findings from this suggested that whilst SuDS are beginning to become the norm, the ‘harder’ solutions are still much more commonplace. On top of that, design and construction remain weakly regulated, and the legal framework of SuDS ownership and maintenance is lacking and unclear. The expert practitioners supported the need for a single method of adoption, which would be coordinated by the local authority. They also suggested that there should be policy changes making SuDS mandatory, as their benefits are clear and this would speed up the rate at which the change happens across the UK. 

If the results of this survey are taken into account and supported by policy makers, there is the possibility for SuDS to become the norm, and help water sensitive systems in their water management.

Full article: State of SuDS delivery in the United Kingdom, P Melville‐Shreeve, S Cotterill, L Grant, A Arahuetes, V Stovin, R Farmani, D Butler, Water and Environment Journal 32 (1), 9-16

Quantifying fat, oil and grease build up in drainage systems

Food service establishments (FSEs) are a major source of fat, oil and grease (FOG) getting into sewer systems. Build-up of FOG can cause major blockages in the systems, which cost the management companies a lot of money to clear, as well as problems for those whose drainage systems are backed up as a result. Therefore it is important to know how to manage FOG, and to do that we need to know how much is entering the system.

Unfortunately, current methods for quantifying FOG in FSE wastewater are unsuitable, due to the interference from other substances like surfactants (the chemicals in detergents and the like) and food residue, which interact with FOG and create a compound called an emulsion. 

Caroline Gurd (Cohort V) led research into a novel quantification method, based on the dairy industry Gerber method. This method negates the effect of surfactants, allowing for FOG to be quantified without interference, making it possible to quantify FOG in a realistic manner. On top of that, the method allows free oils and oils that are part of an emulsion to be quantified separately. This separation allows greater insight into FOG management. The method was tested in both synthetic and real FSE wastewater, which indicated that the novel method is more reliable than standard extractions in FOG-rich systems. 

If this method is implemented by sewer management companies, clearing the sewer systems will be easier and more efficient. This would lead to less money being spent clearing sewer systems, less drainage system blockages, and prevent FOG build up from becoming too big to manage effectively. 

Full article: Determination of fats, oils and greases in food service establishment wastewater using a modification of the Gerber method, C Gurd, B Jefferson, R Villa, C De Castro Rodriguez, Water and Environment Journal

Does media bias affect public opinions on water reuse?

Public opinions on water reuse have been and continue to be a barrier to the success of various schemes. The internet allows many to engage with information surrounding water reuse proposals when they may never have encountered the information otherwise. There are benefits to engaging the public online, but there are also challenges associated with media bias and online advocacy. 

A study was undertaken by STREAMer Daniel Goodwin, with Cranfield University and Thames Water to examine the public response to online news outlets reporting on an indirect potable reuse proposal for London. The researchers examined 1323 online comments on six different articles regarding this proposal. The articles were from a variety of news sources, all from the top ten national readership rankings (bar the BBC, which is the most read but is not ranked with the others). The sources were varied in political leanings and included tabloids and broadsheets. This ensured a wide variety of readers and therefore commenters, as well as different message framing. 

Every article did imply a sense of disgust, featuring the idea of “drinking sewage” and a dominant frame of ‘toilet to tap’. Overall, three of the articles were more balanced in using both positive and negative sentiments towards the proposal, whereas the other three were evaluated as somewhat more negatively biased. 

There was no evidence of the way the media framed the event influencing the public reactions, whether positively or negatively. The study shows that whilst countering long-term agendas will be difficult, there may be benefits to experimenting with the way water safety measures and shorter-term gains are framed. This information is vital to anyone wanting to promote and advocate for water reuse proposals online, leading to more effective communications, and hopefully a more informed public when it comes to water reuse. 

Full article: Evaluating media framing and public reactions in the context of a water reuse proposal, D Goodwin, M Raffin, P Jeffrey, HM Smith, International Journal of Water Resources Development 34 (6), 848-868

How different message framing can affect public opinions on water reuse

Water reuse is becoming more relevant, especially in water-stressed regions, yet it is still seen as a controversial option. Providing information on reuse options can have a positive impact of how acceptable people find the concept of reuse. As a result, there is growing interest in understanding the differing impacts from different ways of communicating these messages. 

This study, led by STREAM researcher Daniel Goodwin, aimed to evaluate the way different methods of framing messages about the safety of recycled water impacts attitudes. 689 participants from London, UK, were split into focus groups. Each group was shown an animation about water recycling safety, with a different framing of the message for each group. There were surveys before and after the animation was shown, allowing the researchers to see the impact on the attitudes depending on the framing of the message in each animation.

The results agree with existing knowledge on the impact of difference types of messaging on public attitudes, including important evidence on the positive impact of water safety communications framed in terms of the compliance with water quality requirements. However, there was not an evident positive impact for messages framed in terms of the technology to remove contaminants, nor in terms of the risks relative to other everyday risks. 

These findings help isolate the effects of specific frames and add to the research on how an increased understanding of risk can influence willingness to support water reuse schemes. These results are of great value to water resource planners in creating communication materials that help to improve public perceptions of water reuse, and this could lead to an even further improvement over a larger time frame. As the UK could soon run into problems with water scarcity, it’s important that we begin to change minds so we can avoid wasting such a precious resource.

Full article:
Informing public attitudes to non-potable water reuse–The impact of message framing, D Goodwin, M Raffin, P Jeffrey, HM Smith, Water research 145, 125-135