Today I attended a NERC webinar on developing low-cost monitoring to evaluate Natural Flood Management (NFM). Marc Mulligan from Kings College London talked about how each NFM technique is different and will vary in design and scale. It’s important to consider geographical context, therefore Mark’s approach aims to monitor a wide range of interventions extensively rather than a single site intensively.
Monitoring is expensive in specialist equipment and sensors, associated infrastructure, as well as time to visit sites, collect and analyse data. Mark explained how to overcome this, they developed a network-connected, low-cost, DIY-build sensors and automatic web-based analysis techniques suitable for replication over large number of sites and NFM measures. This involved using FreeStation loggers to collect data.
Mark mentioned how ground based monitoring infrastructure is declining globally and we cannot remotely sense all the variables we need to measure. Therefore, FreeStation offers an environmental monitoring system with open source DIY hardware. The FreeStation solution includes a variety of instruments, all good enough for measuring what we want. It is designed with consumer, off the shelf, low-cost components, easy to build and install. The project started in 2014, and lots of data has been collected so far. Online tools have also been developed to help us better manage and analyse the data streams.
Low cost does not mean low accuracy, precision or quality. Low cost means non-specialist, consumer, mass produced and using your own labour.
A few examples of where these systems have been deployed include at Blackwater, on the Colne, Mole, Stour, Leck, Mar Dyke and Lannock Manor Farm.
Mark outlined there are 2 different types of NFM – ‘at a point’ and those interventions which retain water over much larger areas. Examples of at a point interventions include stage sensors (similar to low-cost car parking sensor, using sonar sensors) either side of dam. This can then determine the exact distance between the sonar and the water level.