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Construction Inspection Report - Monument Dam <br />Date of Inspection: 4/30/2008 <br />Page 2 of 7 <br />Upstream Slope <br />• Riprap coverage appeared uniform throughout the slope on the main portion of the dam. A few thin <br />spots with exposure of the bedding layer were noted in the area between the left end of the dam and the <br />emergency spillway. In general coverage appeared thorough and uniform. <br />• Gradation of the riprap appeared adequate to fill voids and produce uniform coverage. Brad Lindsay <br />indicated he provided quality control during placement and the constructor used labor to hand place <br />riprap where needed. <br />• It was observed that the riprap layer was extended approximately 2-feet above the elevation of the dam <br />crest and there is some concern that this configuration could cause ponding and prevent drainage of the <br />crest. However, it was also observed that the upstream shoulder of the dam crest generally interfaces <br />with the riprap bedding layer along the full length of the crest, which should provide a sufficient means <br />for drainage. <br />Emergency Spillway <br />• The spillway was used as an access road during construction and remained unaltered with the <br />exception of an area filled-in for temporary access to the dam crest and downstream slope. It was <br />recommended that the spillway crest elevation be surveyed to ensure the historic elevation was <br />maintained. It was also recommended that the centerline grade of the spillway channel be surveyed to <br />ensure positive grade was maintained. <br />• The area filled-in and used as access to the dam crest and downstream slope had been removed at the <br />time of inspection. However, the cross section was less defined than the historic channel and it was <br />recommended that this area be cleaned and reshaped prior to final project approval. <br />Outstanding and/or Unresolved Construction Items: <br />Gage Rod <br />• Provide additional support at upstream end of gage rod. <br />• Verification by Barr Engineering that the gage rod was constructed according to the approved plans <br />and specifications. A follow-up inspection of the gage rod by this office will occur at the final <br />construction inspection. <br />Upstream Slope <br />• Extension of riprap layer above the elevation of the dam crest and interface of the upstream shoulder <br />with the bedding layer should be reflected in the As-Constructed drawings. <br />Emergency Spillway <br />• A survey should be conducted to verify the spillway crest elevation and spillway channel grade. <br />Operator's Platform <br />• Attach outlet vent pipe to the operator's platform as shown on Sheet 15 of the approved plans. <br />• Provide an insect screen on air vent as shown on Sheet 15. <br />• Provide means for outlet hand crank to be lockable. <br />Additional Items <br />• A plan view of the dam with piezometer and seepage monitoring locations, with labeling, should be <br />included in the As-Constructed drawings. <br />• Detail 6 on Sheet 15 of the As-Constructed drawings should accurately reflect the actual constructed <br />diameter of valve stem support blocks.