2019-08-21_REVISION - M1976056 (6)

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McAtee Construction Company Page 2 Bank Armoring Plan East lake Bank Armoring, In East Lake there is a 1, 260 foot section of lake bank within 100 feet of the west ditch that will be armored to urban drainage standards . The ditch bank armoring and much of the levee are on land now owned by McAtee Construction Company. During the 2013 flood even the levee kept the river from entering the area west of the west ditch bank, but water enter from over land sheet flows from south of Highway 6 and the raised groundwater elevation. It appears there is a short section near where the ditch turns to the northeast that may have been over topped and the west ditch bank was damaged from here to the ditch overflow just south of the Permit boundary. This means that north of this point there was no direct connection between the ditch/river corridor so the water accumulated on the land south of the railroad until is soaked into the ground after the flooding ended. For this reason there is no way to construct inlet or outlet spillways in the east lake area that would have a direct connection to the river corridor. The option chosen for this area is to armor the bank following the UDFCD Guidelines . In this area the levee and armoring installed many years ago held up to the flood, the ditch company placed massive amounts of new armoring on the west bank and resized and improved the return flow spillway to allow flood water that enter the upper end of the ditch to return to the river without damaging the ditch. Because of the levee and the corridor armoring we proposed installing the lake bank armoring 100 feet from the west ditch bank along this section. The location of the armoring is shown on the revised Map Exhibit F - Reclamation Plan Map. Bank armoring will be done using the asphalt and concrete recycle material described above using the D50 material size specification. At a minimum the toe of the armoring will be 3 feet below the lowest water level in the lake and 2 feet or more thick. This is approximately 2 . 35 cyd/lft for this area. The armoring will cover the bank slopes from the original ground surface to a depth of 3 feet below the water and parallel to the west side of the levee . Once sloping begins the armoring will be installed on sections completed. Estimated total volume of inert fill (concrete and asphalt rubble) needed to complete the East Lake bank armoring is 2 , 960 cubic yards . Supplied supporting documents 2 - Firmett Maps showing the flood plane area and elevations at mine (2016) Figure G-1 - Bank Protection Plan cross sections