Rain water that does not soak into the ground after a rainstorm is called stormwater. Stormwater can become contaminated when it flows over dirty surfaces or when someone dumps substances like oil, paint, or solvents directly into the stormdrain system. Stormwater flows without treatment directly into Tucson's washes. Additionally, when people dump bulky items such as yard waste into washes or drainage structures, the flow of stormwater can be blocked, causing flooding.
The City of Tucson Stormwater Management Section is increasing public awareness on the importance of protecting our washes and reducing stormwater pollution by marking inlets into the City's stormdrain system. The marking consists of a colorful plastic disc that carrys the message "Only Rain in the Drain" that is fixed to the curb near the stormdrain inlet to remind potential polluters that only rainwater belongs in the stormdrain system.
In order to increase public awareness of Tucson's many watercourses, signs have been installed where roads cross washes. These signs help Tucsonans get to "know their washes." By creating awareness, we hope that citizens will protect the natural habitat found along washes.
You can check on the locations where the Stormwater Management Section has placed curb inlet markers and wash signs by visiting the Stormwater Map at the Transportation Department's Map Guide website. Place a check on the layers named Rain in the Drain Discs and Wash Signs to view the locations of marked inlets and washes.