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<br />(1) "V" Drops or grade control structures: these types of structures are placed across the <br />width of the channel, anchored into the banks and stream-bed. "V" drops are designed to <br />have a "low flow" area, "high flow" area and stepped wing for flood flows and spectator <br />seating at the normal range of flows. These types of structures are built with a slope <br />between 8:1-10:1 that provide concentrated flow, the creation ofa wave-form and a self- <br />scouring plunge pool located below the structure. The crest of these structures is placed <br />at or below the existing channel invert in order to prevent impact on the 100 year <br />floodplain. These types of structures are intended to be navigable for a wide variety of <br />river craft, including drift boats, at a wide range of flows, while simultaneously providing <br />"play-boating" and surfing opportunities at their base. "V" drops are designed to be <br />passable by fish species and provide critical aquatic habitat through the creation and <br />maintenance of the plunge pools. These types of drop structures are ideal when it is <br />necessary to maintain or raise water surface elevations at head-gates for diversions, while <br />simultaneously not impeding recreational boating traffic. <br />(2) Off-set current deflectors: Current deflectors are often built in sets of two. Their primary <br />purpose is to move the focus of the river's flow to the center of the channel while <br />creating eddy pools or slack water along the banks. These types of structures are often <br />incorporated into slalom courses and create outstanding fish habitats. <br />(3) Islands and random boulders: Large (8') boulders can be used in groupings or <br />individually to provide velocity shelter within riffles and high velocity areas for fish <br />habitat. In addition, these types of in-stream improvements create mid-stream features <br />and interest for paddlers. <br />(4) Terraced bank restoration and seating areas: The banks in selective areas can be terraced <br />to create attractive and creative access points, provide seating, stabilize banks, and <br />preserve vegetation. Access to the river from the banks can be encouraged at select <br />areas, while areas for preserving vegetation and for re-vegetation efforts can be set aside. <br />Boulders are anchored into the banks to accomplish these goals as well as to provide <br />bank stabilization and erosion prevention. <br />