Using Mobile Phone Towers to Reduce Sewer Overflow... What?

Photo: Flickr, CC I Feel a Great Disturbance in the Force Finding new uses for equipment that you already have is always satisfying (at least to engineers). One very cool example of this is the use of cell phone towers to measure rainfall in real-time; the rain interferes with the radio signals, and this interference can be measured with "greater spatial resolution than traditional point measurements provided by rain gauges." How is this green? Well, in general it could provide better data about our planet and changing rain patterns, but on the more practical level, it could help reduce the dumping of polluted water in lakes and rivers.

Photo: Flickr, CC

Here's how it works:

Especially in built-up areas, sewer systems are frequently overwhelmed by unexpected rainfall: stormwater is mixed with sewage in pipes, the volume of water exceeds the capacity of retention basins, and the murky mixture overflows into local surface waters. In this way, diluted but untreated wastewater -- containing chemicals such as pharmaceuticals, cleaning agents and pesticides -- is discharged into streams, rivers and lakes. [...]

"More accurate detection of rainfall at the local level would allow sewer systems to be controlled in such a way as to prevent overflows of wastewater as far as possible." Rieckermann, an environmental engineer, is therefore developing a computer model that uses data from a mobile phone network to reconstruct rainfall events at a higher spatiotemporal resolution than is possible with conventional methods. [...]