It's been a little wet here in the UK Maker Belt of late, and the news that another storm is on the way is hardly welcomed - but does make for a fantastic opportunity to shine a light on some projects which aim to offer early warning of impending floods, preventing home and business owners from being caught on the hop and offering more time for evacuation or the construction of temporary defences.
One of the biggest citizen-scientist flood warning projects in the UK is that of our friends at Flood Network, who use Arduino-compatible hardware with an ultrasonic distance sensor and radio to build water level monitoring systems which are then recorded onto a publicly-accessible map. As more nodes are deployed, the ability of the overall system to provide early warning of impending flooding downstream of the sensors improves dramatically - and the sensors themselves are open hardware courtesy the Oxford Flood Network, the Flood Network's original implementation.
There are, of course, smaller-scale projects too. An Instructable published earlier this year demonstrates how to build a basement flood alarm which provides an alert when excess moisture - or flood waters - are detected within the property, and can be easily built and programmed by even an Arduino beginner. Robot Geek extends this concept by replacing the alarm with an automatic pump, suitable for draining smaller areas though scalable through the use of more powerful pumping systems and suitable relays - always remembering, of course, that electricity and water don't play nicely together!
For more academic implementations, there are papers on an Arduino-based flood monitoring system with SMS alerts built by the University of the South Pacific in Fiji, a more general-purpose disaster alarm system featuring an Arduino Uno and Zigbee radio network built by King Mongkut's University of Technology in Thailand, a deployment of a Arduino flood-sensing framework in rural Rwanda performed by the Kobe Institute of Computing in Japan, and even a Microsoft Research project on the topic in collaboration with the Massachusetts Institute of Technology. For something a little more out-of-the-ordinary the Cave Pearl Project is blog following a project to build a submerged flow sensor, primarily designed to monitor flooded cave systems, at a fraction of the cost of a commercial variant.
From all these projects, there is one clear message: with tools like the Arduino platform it's never been easier for citizen scientists to get involved in monitoring and reporting on the world around them, and low-cost sensor networks can provide real and valuable data which could help lessen the impact of flooding like that we've been experiencing in the UK recently.