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<br />. <br /> <br />Cross-section ill is the furthest upstream in the survey site (see Plate I) and is located just <br />upstream from the abandoned beaver dam. Bankfull elevation was not well expressed in <br />this section of the stream therefore was not estimated for this cross section. The cross <br />sectional profile does show a flat area on the right side of the channel that is about 10 <br />meters wide, but this surface is interpreted as the bed of the old beaver pond and was not <br />constructed by the active channel. <br /> <br />~;~::;j? <br /> <br />Table 1. Bankfull-derived parameters for channel cross sections. Elevations, depths and <br />widths are expressed in meters. Slope is unitless (i.e. meter/meter or foot/foot). A <br />bankfull surface could not be identified for Cross Section III, so associated parameters <br />could not be estimated. BP=Bankfull; FP=Plood prone (at twice bankfull depth). Rosgen <br />(1996, pg. 5-7) slope designations: a+ for slopes steeper than 0.100; a for slopes of 0.100 <br />to 0.040; b for slopes of 0.039 to 0.020 <br /> <br />. <br /> <br /> Cross Cross Cross <br />Parameter Section Section II Section III Average <br /> I <br />BP Elevation 97.965 96.104 ND ------ <br />BP Depth 0.111 0.152 ND 0.132 <br />BP Width 3.50 2.80 ND 3.15 <br />BP Width/Depth 31.67 18.37 ND 25.02 <br />FP Width 6.00 7.00 ND 6.50 <br />FP Width / BF Width 1.71 2.50 ND 2.11 <br />Channel Slope 0.074 0.108 0.031 0.071 <br />Ros,:?;en Slope desi1mation a a+ b a <br /> <br />Longitudinal Profile <br /> <br />The location of the longitudinal profile is shown on Plate I and the profile data is listed in <br />Appendix II. Figure 15 shows the profile of the channel bed and water surface. The <br />change in slope at 40 to 49 meters is the approximate location of the breached beaver <br />,.C", dam. A large change in slope at approximately 79 m marks an unstable section of the <br />stream which has been diverted by riparian growth and produced a small waterfall <br />(Figure 16). The diversions and small waterfalls in this section indicate that this is an <br />unstable reach. In general, the stream is fairly steep with an average gradient of 0.0396 <br />over its entire length of approximately 121 m. The sinuosity of the stream is 1.197 <br />(distance channel follows divided by straight-line valley length). <br /> <br />The longitudinal profile was divided into two sections: upstream and downstream. The <br />upstream section was the upper 61 meters of the stream and the downstream section was <br />the lower 60 meters of the stream. Sinuosity of the upstream section was 1.095 with a: <br />slope of 0.0419 (Rosgen "a" slope). Sinuosity of the downstream section was 1.255 with <br />. a slope of 0.0377 (Rosgen "b" slope). In summary, the upstream section had a steeper <br /> <br />4 <br />