Current Research in Environmental Sustainability 3 (2021) 100059 Available online 1 July 2021 2666-0490/© 2021 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Designing citizen science for water and ecosystem services management in data-poor regions: Challenges and opportunities B. Pandeya a, b, * , W. Buytaert b, c , C. Potter a a Centre for Environmental Policy, Imperial College London, UK b Grantham Institute for Climate Change and the Environment, Imperial College London, UK c Department of Civil and Environmental Engineering, Imperial College London, UK A R T I C L E INFO Keywords: Citizen science Low-cost sensors Data co-generation Water ecosystem services Local decision-making ABSTRACT While the citizen science approach has gained prominence in water and ecosystem services management, methodological limitations, insuffcient resources invested in monitoring practices and a lack of effective mechanisms for integrating the approach into existing monitoring and decision making processes means that its full potential has yet to be realized. Nevertheless, the concept offers a real opportunity to address data gaps and assist decision makers operating under a wide range of socio-ecological and environmental uncertainties. In this paper, we report fndings from a project in which low-cost sensors were deployed to collect hydrological data in two study locations in Nepal. We found evidence that the citizen science has potential to generate locally relevant data and knowledge which can enrich a much more polycentric governance of water ecosystem services man- agement. However, some major challenges need to be overcome, in particular developing locally-tailored monitoring sensors, standardizing monitoring and data sharing practice, improving local capabilities to collect quality data and making the approach more sustainable and adaptive to emerging environmental threats and uncertainties. If suffcient attention can be given to these key challenges, citizen science looks set to play a signifcant future role in water and ecosystem services management. 1. Introduction A voluntary involvement of lay publics (non-scientists) in scientifc research is generally termed ‘Citizen Science’- CS hereafter. There is a long history of citizen's voluntary participation in scientifc enquiries in a variety of ecological and environmental resource management con- texts (Irwin, 1995; Silvertown, 2009; Miller-Rushing et al., 2012). CS can be broadly defned as the voluntary participation of individuals and communities in research design, data co-generation and interpretation, often in association with or under the guidance of scientists (Bonney et al., 2009; Dickinson et al., 2012; Buytaert et al., 2014). In the last two decades, CS initiatives have made a signifcant contribution in ecolog- ical and hydrological research and data collection (Cohn, 2008; Dick- inson et al., 2012; Bonney et al., 2014; and Njue et al., 2019). Community-based hydrological monitoring has also become a successful measure to generate quality data and enhance local people's under- standing of key hydrological functioning (Walker et al., 2016). As a result, CS is becoming an important form of public participation in natural resources management and therefore is receiving increasing attention in public policies and decision making processes (Haklay, 2015). CS-based practices have an ever increasing footprint in a range of ecological and environmental research activities, including species range shifts, water quality and quantity monitoring, spread of infectious disease, demographic changes, land use alternation and climate change impacts (Roy et al., 2012; Palacin-Silva et al., 2016). An immense level of data generated by citizen science projects suggest growing public enthusiasm and willingness to engage with environmental concerns. CS has also become an established research protocol for some large scale monitoring of biodiversity and ecological processes. For example, the Open-Air Laboratories (OPAL) project in the UK (www.imperial.ac. uk/opal) was designed for participatory monitoring of water, air, in- sects, birds and wildlife habitats (Davies et al., 2013). Similarly, the ‘eBird’ programme is a web-based volunteering programme (http://ebi rd.org/content/ebird/about/) for documenting presence or absence and abundance of bird species in North America all year round (Wood * Corresponding author at: Imperial College Research Fellow, Centre for Environmental Policy, Imperial College London, 402 Weeks Building, 16-18 Prince's Gardens, South Kensington, London SW7 1NE, UK. E-mail address: b.pandeya@imperial.ac.uk (B. Pandeya). Contents lists available at ScienceDirect Current Research in Environmental Sustainability journal homepage: www.sciencedirect.com/journal/current-research-in-environmental-sustainability https://doi.org/10.1016/j.crsust.2021.100059 Received 12 October 2020; Received in revised form 19 May 2021; Accepted 17 June 2021