River Gauges or Flow Meters are an important resource to steelheaders. Discharge Cubic Feet Per Second (CFS) tells you what the flow is. Some meters also have a temperature gauge which doesn't matter anyway to hardcore steelheaders. Most OH Rivers are prime fly fishing when the CFS is 250-300 and falling.
www.riverboss.com is a great site that has both desktop and mobile web sites where you can customize what rivers gauges and what weather you want to view. Riverboss is worth checking out.