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ENVIRONMENT, INC. <br />FEBRUARY 19, 201 5 <br />PAGE 2 <br />entire length. At this point in time the entire length of the trench has been cleaned and <br />sloped so water is free flowing from the start to the out -fall at the river. At this time <br />the water passing thru the pipe is approximately 2 inches deep. <br />Section 1 - River to Slough <br />The outlet was built by excavating a trench wider then the pipe and lining the north and <br />south side with large boulders (3 foot +). The bottom was lined with "H" rock creating a <br />rock splash pad for the discharge water and the areas behind the boulders was line with <br />1" rock. The pipe outlet side was armored using the same rock used for the backf ill <br />around the boulders. The armoring around the pipe ends were built in accordance with the <br />section shown on the design plan originally submitted in January 2015. Two large boulders <br />were placed at the end of the outlet pad to prevent the area from becoming a backwater <br />if the river elevation reaches this height. They will prevent flotsam from collecting <br />around the outlet that could restrict flow from the trench. The base elevation of the pad <br />is 4998.17. The bottom of the 12 inch outlet pipe is 4998.7 and the inlet side of the pipe <br />is 4999.42. When this was' completed, the material between Section 1 and 2 was opened <br />allowing the entire trench to drain. Cross Section A -A' shows how this area was built. <br />In Section 1 the bottom of the trench is approximately 8 feet wide and lined with 1" rock <br />along the entire 240 feet, with side slopes graded to approximately 3 :1. When <br />construction is compete this section of trench will be narrowed so the bottom is <br />approximately 6 feet wide and the side slopes will be 3:1 or less from the end of Section 2 <br />to the inlet side of the pipe, as shown on cross - section B -B'. The elevation at the head <br />end of Section 1 is approximately 5002.5. <br />Section 2 - old slough section <br />In Section 2, after the initial cut thru drained the area, a trench 6 foot wide by 2 foot <br />deep by 375 feet long was excavated thru the bottom of the old slough area from the <br />head of Section 1 to the original trench that started on the north end of the house. This <br />left the bottom of the trench in native gravel with a clean bottom. Prior to this, the old <br />slough did not have a distinct channel so water flow was restricted, creating slack water <br />areas. The new channel confines the water to a flow channel with a clean gravel bottom <br />with 3 to 6 inches of water flowing down it. When this section is complete, the slopes of <br />the new trench will be graded 3 :1 or less. The bottom of the old slough east of the new <br />trench will remain undisturbed and the west side will be slope 3:1 where needed. The <br />bottom elevation of the top end of Section 2 is approximately 5002.6. Cross- section C -C <br />show a typical profile for this section of ditch. <br />Section 3 - old slough to head of original groundwater ditch <br />This area runs along the south and east sides of the backfilled area. This area is 302 <br />feet long has been cleaned of vegetation and rough graded so the bottom is approximately <br />4 feet wide and slopes from 5004 at its head to 5002.6 where it connects with Section 2. <br />