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Attachment A <br /> Topographic Suvyey (to be conducted 6v the City) <br /> A detailed topographic map will be instrumental to Inter-Fluve, Inc. for developing a HEC-RAS model of <br /> existing and design hydraulic conditions for the creek and its floodplain. City staff will use the map to <br /> prepare construction plans and measure earthwork volumes (cut and fill). <br /> The City of Eugene will prepare a topographic survey through the common space and private properties <br /> along the W 34t'' Avenue drainage. The City's scope of work for surveying services will include: <br /> 1) The topographic survey shall provide complete coverage of the following: common space area, lower <br /> portions of the Rockett and Hanson properties, area within 50 feet of the culvert outlet below W 37`s <br /> Avenue, and area within 75 feet of the culvert at Frederick Court. <br /> 2) Data points shall be sufficient to provide a 1-foot contour interval map. Breaklines shall be sufficient <br /> to resolve slope breaks, topographic lows and drainage features, changes in channel or floodplain <br /> geometry, and vegetation that may act as a hydraulic control. <br /> 3) Survey two stream and floodplain cross-sections downstream of Frederick Court. One cross-section <br /> should be located just below the culvert outlet and associated scour pool. The second cross-section <br /> should be located another 50 feet downstream. <br /> <br /> 4) For stream geometry, collect data points for the following: (a) top and toe of each bank, (b) channel <br /> invert of low flow channel, and (c) at significant changes in elevation or alignment. <br /> 5) For floodplain geometry, (a) collect data points up to an elevation that corresponds to the foundations <br /> of houses that are adjacent to the floodplain, (b) identify breaklines at breaks in slope, and (c) indicate <br /> perimeter for areas of dense vegetation. <br /> 6) Survey a profile along the stream's low flow channel thalweg (not centerline) to show slope breaks <br /> along the streambed, to accurately depict bends or meanders along the stream, and to show location, <br /> length and depth of existing pools. The prof le should extend from about 75 feet below Frederick <br /> Court to the outlet of the W 37`~ Avenue culvert outlet. <br /> 7) Verify existing information on culverts located in the drainage including: number of barrels, shape, <br /> material, size/diameter, length, invert elevations, and depth to streambed from invert. For the <br /> culvert(s) under Frederick Court survey the elevation at which the culvert is overtopped (i.e. low <br /> point on the road). <br /> Research and provide Iocations of utilities, easements, public right-of--way, tax lots, environmental <br /> overlay zones, etc. <br /> 9) In the field, locate and survey existing infrastructure (e.g., sanitary sewer lines, power lines, etc.). <br /> Where possible, survey pipe crowns and/or inverts. <br /> 10) Verify and/or survey location, diameter (at breast height) and species of large trees along the <br /> proposed stream alignment and within proposed disturbance areas. Helen Rockett has expressed <br /> concerns about potential impacts to trees located on the lower portion of her property near the <br /> proposed stream alignment. Hence, take care to verify tree locations, diameter and species on her <br /> property. <br /> <br />