Monitoring Plan: Monitoring of the project after construction for 5 years to include: adult fish passage through the grade control sill during low flow, percent cover vegetation during years 1, 2, and 5. The riparian habitat quality will be assessed using the Washington State Wetland Function Assessment Project plant community model (Hruby et al, 1997). Total cost of monitoring is $10,000. For monitoring updates see http://www.nws.usace.army.mil/publicmenu/DOCUMENTS/Sammamish.pdf; Resource Issue: The Sammamish River suffers from severe high temperature problems (as high as 82 degrees F in late summer), and low flows during late summer and early fall. Water quality and fish passage problems over a grade control sill exist due to low flows and heavy public use and off leash dog areas nearby. These factors contribute to heavy bank erosion and loss of vegetation.; Projected Outcomes: A connected fish and wildlife habitat corridor from Lake Sammamish to the grade control sill. Improved water quality and reduced erosion. 1 acre of high quality riparian habitat will be created, and an increase of approximately 1000 salmon during the adult migration (approximately 6000 enter the Lake Sammamish system currently). ; Design Measure: The width of the low flow notch will be reduced from 12 feet to 4 feet in the grade control sill, and the notch will be deepened to elevation 23.75 feet MSL. This will concentrate the flow and provide deeper water through the notch. This concentration of flow will allow adult fish to clear the notch more easily and increase attraction flows to encourage adults towards the grade control sill, but will not affect the lake level during any season. The project will also fence the riverbank along teh flood control channel, and encourage river access only in four selected areas. These selected areas will be protected from erosion. Native trees and shrubs will be replanted in all areas between the access points.Endangered Species: Coho Salmon, Chinook Salmon, Steelhead Salmon. Project Number: 105 in WA
