So far we've had sensors to monitor dams, levees, and bodies of water to give early warning of flooding and sensors around ocean shores to warn of impending tsunamis. Now, sensors are moving into the lakes to perform real-time monitoring there.
According to the Minneapolis-St.Paul Star Tribune article "Underwater sensors help scientists monitor water", researchers are adding underwater sensors to creeks and lakes around the Twin Cities. The sensors (which measure water depth and flow, turbidity, temperature, salinity, pH, and nitrate and oxygen levels) transmit their data via cell phone back to the researchers, where the researchers can assess how well the state and city's pollution removal methods are working. Although the initial project will only collect data over a three month timespan, further study would involve sensors left in the water over much longer periods of time.
Heading the research is Professor Bill Arnold, of the University of Minnesota's Department of Civil Engineering, who has been focusing on how organic chemicals fare in aquatic systems, both natural and manmade. The general idea is to monitor the pollution levels in the water and assess how well pollution removal systems are working and, generally, creating a far more detailed understanding of water quality and conditions in the lakes and streams being studied. Using a sensor network, he and his fellows can amass far more information, both qualitatively and over time, than is available using more traditional methods.
Over the last several years, the weather patterns in the U.S. and elsewhere appear to be changing. The U.K. now seems more prone to torrential rainstorms and flooding than ever before. The Midwest and Northeast regions of the U.S. have likewise been plagued with more rain than we either need or want. (For the most up-to-date information on excessive rainfall around the world, visit NASA Goddard's Tropical Rainfall Monitoring Mission (TRMM)) For our increasingly urbanized lives, the combination of excessive amounts of water falling from the sky and stormwater drainage systems that aren't up to the task presents a real problem. Storm runoff sluices whatever crud, ick, and dirt lies in its path, ferrying it into nearby bodies of water.
Real-time systems such as these can (I hope) help pinpoint which areas of the drainage system are doing well and which need revision or redesign. They can also give more timely alerts of pollution emissions into existing water systems. More and better data can lead to more efficient and more effective care of surface water.