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Description: Background. There is growing recognition of the co-benefits generated through improved provision of natural spaces within an urban context, both in terms of biodiversity conservation and public health. In terms of the latter, much of the research suggests that stress reduction and psychological restoration play a major role in the observed health benefits. Yet there are few experimental studies that specifically address the link between exposure to specific natural environments and physiological and/or psychological changes. Furthermore, the potential salutogenic (health-improving) impact of aquatic environments (or “blue space”) is relatively understudied compared to green space. Here, we outline results from a feasibility study examining the use of low-cost measurement tools to quantify the psychophysiological effects of short-term exposure to blue space within an urban setting. Method. The study took place at the WWT London Wetland Center, which is characterised by a stark contrast between biodiverse wetland habitat and a typical urban setting. Thirty-six healthy participants were exposed to 3 settings in counter-balanced order: an indoor space, a wetland and an urban site. We continuously recorded electroencephalographic data and real-time physiological stress responses in addition to obtaining self-reported mood states following exposure. Results. We found a significant effect of site on mean resting heart rate, with increased HR in the urban setting, although this was only observed in stressed individuals. In contrast, we found no significant differences in other stress-related measures, including various metrics of heart rate variability and electrodermal activity. The EEG data showed modulation of high beta band activity only in the wetland setting, potentially related to changes in attention. However, the EEG findings are made questionable by the low quality raw signals and artifacts during acquisition caused by movement and – possibly – environmental interference. In contrast to most of the physiological measurements, we have confidence in the significant changes in self-reported mood. These measures demonstrated an increase in positive feelings in the wetland setting. We also noted a pronounced decrease in negative feelings reported in the wetland setting, but this was observed in stressed individuals only. Discussion and conclusions. Our findings partially support the use of low-cost psychophysiological measurements to quantify the potential stress-reducing effects of blue space exposure in urban dwellers. Interestingly, our results suggest that pre-existing stress levels may be an important modulator of the salutogenic effect. Despite previous reports of successful use of similar low-cost portable EEG devices (e.g. see Aspinall et al 2015), we encountered significant technical limitations that call into question the reliability of the method when deployed in situ. Further refinement of the technique is required for this approach to become a viable monitoring tool to support evidence based decision making in the area of public health and green/blue space provision. The possibility to use the more robust physiological measurements to monitor the effects of social prescriptions for people with stress-related health problems should be considered a priority for further research.