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<br />SHEET 2 DISCUSSION
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<br />B, Storm Sewer
<br />I. 54" RCP (410 L,F,).............................",...........,...$ 47,200
<br />2. 60" RCP (290 L,F.)....,..,.............,."......,.,..,........,.$ 40,600
<br />3, 66" RCP (840 L,F,).... ,.. ,....'"'..'"""..,, ,..""".. '.'" ,.$142,800
<br />4. 48" x 76" RCP (290 L,F,),."....,.....,....."",.......".......$ 60,900
<br />5, 58" x 91" RCP (170 L.F.)."",.,....",....,.."............,...,$ 51,000
<br />6. Manholes/Vaults (10)....""..,..,.",..,...."....,.,..,..,.... ,$ 25,000
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<br />7, Inlets (10),."",..",."".."""""""",.....",..,..".. ,$ 20,000
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<br />The improvements shown on this sheet consists of a system of 54-inch and 42-
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<br />inch RCP parallel to the existing storm sewer system, The existing capacity of
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<br />the system is approximately half the 5-year storm values and is more cost effec-
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<br />tive to augment the existing system compared to replacing the sewer entirely. The
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<br />parallel design will require large vaults at the manhole locations with special
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<br />shaped inverts and deflectors to minimize transition and bend losses, At the
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<br />ourfall to Powers Park, an outlet structure similar to the one presently in place
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<br />will be required,
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<br />C, Utility Relocation (2100 L.F,),.""""",..,...,...,..,.".,.."..,$ 12,600
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<br />SUB-TOTAL $444,200
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<br />The existing 42-inch RCP upstream of Littleton Boulevard should be replaced
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<br />with a single larger HERCP because of lack of capacity right-of-way constraints,
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<br />and potential utility conflicts.
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<br />Contingency (15%)..,....",..,...... 66,300
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<br />Legal and Administrative (5%)..., 22,200
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<br />Most of the pipe in this reach will be under outlet control with the HGL above
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<br />the crown of the pipe, This is caused by the backwater effect of the 5-year water
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<br />surface at Powers Park and the relatively flat sewer slopes required to avoid uti-
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<br />lities,
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<br />SUB-TOTAL $532,700
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<br />Engineering (15%),....,.",..""." 79,900
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<br />TOTAL CONSTRUCTION COST $612,600
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<br />The entire reach shown on the Sheet 2 is characterized by a high concentration
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<br />of existing utilities which severely restricts the alignment of the proposed storm
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<br />sewer, There is little information about the locations and depths of the existing
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<br />sanitary sewers in this area, Prior to any design, these utilities must be carefully
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<br />and accurately located,
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<br />D. Annual Operation and Maintenance (2100 L,F,),..,..., ,..,..........., ,$ 12,600
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<br />Cost of Proposed Improvements
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<br />A, Powers Park
<br />J, Spillway Improvements",,""""""""""""""""""'" ,$ 28,000
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<br />2, Outfall Structure"" ""'" '.,..,..", ".."".."" ",.. ".",,$ 5,000
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<br />3, Low Flow Channel (400 L,F,)""""".."",.."..""".""",,$ 12,000
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