Protecting rivers by integrating supply-wastewater infrastructure planning and coordinating operational decisions
File(s)
Published version
Author(s)
Dobson, Barnaby
Mijic, Ana
Type
Journal Article
Abstract
Placing water quality in rivers at the centre of water infrastructure planning and management is an important objective. In response there has been a range of 'whole system' analyses. Few studies, however, consider both abstraction (water removed from rivers) and discharge (water returned) to inform the future planning of water systems. In this work we present a systems approach to analysing future water planning options where system development prioritises the water quality of the receiving river. We provide a theoretical demonstration by integrating water supply and wastewater infrastructure, and downstream river water quality, on an open-source, stylised, systems model for London, UK, at a citywide scale. We show that models which consider either supply or wastewater separately will underestimate impacts of effluent on the water quality, in some cases by amounts that would require £1 billion worth of infrastructure equivalent to mitigate. We highlight the utility of the systems approach in evaluating integrated water infrastructure planning using both socio-economic and environmental indicators. Through this approach we find unintended impacts from planning options on downstream river quality; including benefits from water demand management and rainwater harvesting, and costs from wastewater reuse. Finally, we present a novel management planning option between supply and wastewater, which we refer to as Abstraction-Effluent Dilution (AED), that is, to reduce river abstractions during high precipitation events to dilute untreated sewer spills. The AED option is found to provide up to £200 million worth of equivalent infrastructure in river quality improvements and has minimal impact on the reliability of water supply while requiring only a change in operational decision making. The results highlight that seeing our water systems differently with this holistic approach could fundamentally change the way we think about future water infrastructure planning so that it works both for people and the environment.
Date Issued
2020-11-26
Date Acceptance
2020-08-18
Citation
Environmental Research Letters, 2020, 15 (11), pp.1-13
ISSN
1748-9326
Publisher
Institute of Physics (IoP)
Start Page
1
End Page
13
Journal / Book Title
Environmental Research Letters
Volume
15
Issue
11
Copyright Statement
© 2020 The Author(s). Published by IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
License URL
Sponsor
Natural Environment Research Council (NERC)
Identifier
https://iopscience.iop.org/article/10.1088/1748-9326/abb050
Grant Number
NE/S003495/1
Subjects
Meteorology & Atmospheric Sciences
Publication Status
Published
Date Publish Online
2020-08-18