REQUESTED INFORMATION
1. Location of observation - this will often be your reporting station, but if conditions are different upstream and downstream, please note the difference.
2. Amount of shore ice along the banks - note the width of the band of shore ice in feet or percent of river width (e.g. 5% of river width on left bank and 15% of river width on right bank).
3. Amount of ice in the open channel - note the estimated percent coverage of the moving ice in the river to the nearest 10% (e.g. estimated 60% coverage of moving ice); the estimate is most accurate if you can look down from a high view point. Many of you will have to make this observation from ground level; it is easy to overestimate the ice coverage from this perspective.
4. Size and color of ice observed - note the size and color of the ice; generally colors green, blue, or white ice indicate relatively strong ice, while gray or black ice indicate relatively weak ice.
5. Ice movement - note whether ice is moving very slowly, slowly, average, or fast; compare to speed of normal river flow.
6. River level trend - note whether river level is rising, steady, or falling.
7. Remarks - any other observations concerning ice characteristics should be noted.
Freeboard - The vertical distance from the water surface up to the top of the bank (freeboard to top of bank) or to a level that will cause flooding of structures (freeboard to flooding).
Ice Chunk - Piece of ice that is about as large as the size of an automobile.
Ice Floe - Ice sheet that is as wide as the winter river channel and longer than it is wide; an ice floe will easily jam in bends or will jam if it rotates sideways in the channel.
Ice Pan - Ice sheet that is less than the width of the river in width and length; large pans are roughly greater than 1/2 the width of the open channel and small pans are less than 1/2 the width of the open channel.
Left and Right Bank - Relative river bank location as you would see it as you stand looking downstream. Lifted Ice - Early in the breakup process, sheets of ice may be floated by the rising water level in the river, lifting the ice up from its winter level; the ice may be in- place if it does not move after being lifted or shifted if it drifts to a new position in the wider river channel.
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