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<br />I <br />I- <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />e. Other Features <br /> <br />Existence of upstream tributaries, bridges, dams, or other <br />features, that may affect flow conditions at bridges. <br /> <br />2. CONDITIONS AT BRIDGE <br /> <br />a. Substructure (See discussion under Section C-1 above.) <br /> <br />b. Superstructure <br /> <br />Evidence of overtopping by floodwaters (Is superstructure tied down <br />to substructure to prevent displacement during floods?) <br /> <br />Obstruction to floodflows (Ooes it collect debris or present a <br />large surface to the flow?) <br /> <br />Design (Is superstructure vulnerable to collapse in the event of <br />foundation movement as are simple spans and non-redundant design <br />for load transfer?) <br /> <br />c. Channel Protection and Scour Countermeasures <br /> <br />Riprap (Is riprap adequately toed in or is it being undermined and <br />washed away? Is riprap pier protection intact, or has riprap been <br />removed and replaced by bed load material? Can displaced riprap <br />be seen in streambed below bridge?) <br /> <br />Guidebanks (Spur dikes) (Areguidebanks in place? Have they been <br />damaged by scour and erosion?) <br /> <br />Stream and Streambed (Is main current implying upon piers and <br />abutments at an angle; is there evidence of scour and erosion of <br />streambed and banks, especially adjacent to piers and abut.ents? <br />Has stream cross section changed since last measurement? In what <br />..ay?) <br /> <br />d. Waterway Area (Ooes waterway area appear small in relation to stream <br />and its floodplain? Is there evidence of scour across a large portion <br />of the streambed at the bridge? Do bars, islands, vegetation, and <br />debris constrict flow and concentrate it in one section of the bridge <br />or cause it to attack piers and abutments? 00 the superstructure, <br />piers, abutments, and fences, etc. collect debris and constrict flow? <br />Are approach roads regularly overtopped? If waterway opening is <br />inadequate, does this augment the scour potential at bridge <br />foundations?) <br /> <br />55 <br />