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11 <br />The left bank gravel bar below the OHWL is now functioning as expected. Prior activities on the <br />gravel bar have had no affect on the function of the River or over-bank area. The materials that <br />washed into the site earlier this year are part of the normal floodplain formation process which <br />occurs throughout the River corridor. Future, higher flows may very likely deposit additional <br />gravel on top of that deposited in 2009. Because the River is generally unstable, avulsing* and <br />occasionally experiences flows of very high magnitude, each year there is the possibility that a <br />very large flow event may overwhelm the reach and the High Flow Channel restoration and <br />initiate changes to the Channel that would prevent the wetland restoration. <br /> <br />4.6.2 Right Bank <br />The fill material placed in the Herbaceous Wetland will be removed and the site will be excavated <br />to match or be slightly lower than the grade and elevation of the adjacent Herbaceous Wetland. <br />The undisturbed portion of the Herbaceous Wetland is well vegetated with wetland species, <br />indicating that the proposed elevation is suitable and the hydrology is adequate for the growth of <br />wetland plants. The proposed riprap will protect the short exposed section of right bank from <br />erosion. Because the River is generally unstable, avulsing and occasionally experiences flows of <br />very high magnitude, each year there is the possibility that a very large flow event may overwhelm <br />the reach and the wetland restoration and initiate changes to the channel that would prevent the <br />restoration. <br /> <br />The Low Water Crossing Wetland restoration already has a hydrology appropriate for wetland <br />restoration, as there have been no major changes to the landform. <br /> <br /> <br />5.0 Proposed Success Criteria <br />Success Criteria have been developed for the wetlands to be restored in the High Flow Channel <br />on the left bank and the Herbaceous and Low Water Crossing Wetlands on the right bank. <br />However, it should be noted that the High Flow Channel may fill with sand and gravel from flood <br />events in the future, change the hydrology of the site, and create conditions appropriate only for <br />upland plants. Under this natural scenario, it would not be possible to restore the wetland in the <br />High Flow Channel. Also, there is the strong possibility that high flows in the River could erode <br />the restored Herbaceous and Low Water Crossing Wetlands, or even bury them in sand during the <br />restoration period. Builders Aggregate Company should not be responsible for any natural <br />process of the River that disturbs the three restorations. <br /> <br />First Growing Season <br />1. The proposed volume of fill material has been removed from the fill area on the left (High <br />Flow Channel) and right (Herbaceous Wetland) banks and the desired topography has <br />been achieved. <br />2. The proposed final grade of the restoration sites has been achieved. <br />3. The soils of the restoration sites are saturated throughout the growing season or during <br />spring high water flows of the River, sufficiently to sustain a wetland. <br />4. The surface of the restoration sites, including bordering uplands, is stable and does not <br />show signs of detrimental erosion. <br />5. Three of the four peachleaf willows planted are alive, vigorous, and producing new <br />growth. <br />6. 90% of the willow sprigs are alive, vigorous, and producing new growth. <br />7. The herbaceous seeding is germinating and establishing an even cover in the Herbaceous <br />and Low Water Crossing Wetlands. <br /> <br />* Avulsing – Undergoing sudden changes in the course of a river.