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II II II I I I I II I I I I I I I I I I I to the U.S. Army Corps of Engineers' design guidelines for levees which would make it impermeable and would add two more feet of freeboard. Area 3 - Three structures here could be affected if flows equal to or greater than the 100-year event occurred. With the levee on the south stream bank, water would flow over the road on the north side, but at depths of less than one foot. If high waters threaten the structures they can be protected by a temporary local measure like sandbagging. Area 4 - Just below the confluence of Buzzard Creek with Plateau Creek the channel is quite shallow and therefore has a limited capacity. Without the existing levee and sandbags already in place the channel could handle only 1900 cfs or the 4-year flood event. By making the existing levee permanent the two structures in these areas could be protected from flows in excess of the 100- year event. As in Area 2, the levee should be constructed according to Corps of Engineers' design guidelines. Area 5 - This property was threatened through bank erosion during last years runoff. With the change in stream channel location in this area, the erosion threat is somewhat reduced, however, consideration should be given to riprap bank protection along the southeast corner of the property as a permanent protection measure. STREAM MONITORING Some form of stream flow monitoring is recommended for Plateau and Buzzard Creeks, especially during snowmelt season, in order to keep track of the rising and falling trends of the flood peaks. In addition to serving as an indicator of an ensuing flood event, the stream gage records, over a number of years, will serve as a point of reference. After a few years a range of "normal" runoff values will become evident and excessively high flows can be identified as an indicator of a potential flooding situation. The flow monitoring device recommended i5 a staff gage. This could be a board mounted on one of the bridge abutments marked off in even increments or the markings could be painted directly on the abutment. The marks should be at one foot intervals with 0.1 or 0.2 foot subdivisions. To properly relate to the rating curves (Figures 1 and 2) developed at the bridges, the zero mark on each staff gage should be the same elevation as the channel invert. These gages will not be very sensitive to low flows but they should be adequate for their intended purpose; estimating flows and tracking the rate at which the water level rises du~ing high flow periods. 4