Pima County Offers Way to Track Rainfallby Pima County News on Aug. 23, 2012, under Pima County, Public safety, Regional Flood Control District, Tucson, Water
Want to know just how much rain is coming down when thunderstorms rattle your windows and lightning streaks across the sky?
The Pima County Flood Control District has a network of rainfall and streamflow gauges within most of the large watersheds affecting eastern Pima County that can give residents real time information on storms in their area.
The system is comprised of 93 precipitation gauges, of which 36 include stream gauges, and is used to assist the National Weather Service with its flood watch and warning advisories.
This information is also readily available to residents who want a better read on what’s happening closer to home, since seasonal storms can produce rather localized periods of heavy rainfall.
“Naturally, we can all look out the window and see that it’s raining, but by checking this system, residents can be more aware of whether there are areas around their homes or along their routes that might be at risk of flash flooding,” said Chris Cawein, deputy director of Flood Control.
The equipment consists of one-foot diameter pipes that house a tipping bucket rain gauge and a transmitter that send signals every time .04 inches of rain is collected. Stream flow is also measured at some of the sites.
That field information is collected, transmitted to a central location and downloaded instantly to the website.
County professionals watch areas more closely that are getting one inch of rain or more in an hour, keeping an eye on road crossings, for example, that might become problematic during heavy rainfall.
By tracking rainfall in the mountains, viewers can have a better idea of what may be headed their way. The system also allows users to go back and look at historical data, which may be useful in reconstructing storm events.
The County started the ALERT system in the 1980s, and has added new rain and stream gauge sites as needs are identified, with recent additions within the City of Tucson and Oro Valley.
To check out the system for yourself, click here: http://rfcd.pima.gov/wrd/alertsys/index.htm
Another Internet resource residents may find helpful is rainlog.org, which is a network of volunteer weather observers who help record daily rainfall amounts using rain gauges they have installed at their homes.