Should you happen to find yourself near Mill or Germany Creek this weekend, don't be alarmed if the water is a little orange. We received notification that the Department of Ecology will be doing a time-of-travel study using a fluorescent dye. According to the DOE, it is "very visible at the point of injection, but disperses as it moves downstream." It is a harmless Rhodamine WT dye at a low concentration. They track the dye with fluormeters installed at the upstream end and the downstream end. It tells them how long it takes for the water to travel.
So, there you have it.