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1-06 Location: Storm drain lines shall normally be located on the north <br /> and east sides of streets with the centerline of pipe five feet <br /> (5') from the centerline of street. Other locations may be allowed <br /> where an economical advantage can be shown, to avoid conflicts <br /> or for other sound reasons. <br /> <br />1-07 Depth: All new storm drain mains shall have a minimum cover of <br /> forty two inches (42") when practicable. Cover may be decreased <br /> to avoid conflicts and on short materials. Special bedding or <br /> protect~ion may be required where cover is decreased. <br /> <br />i-08 Inlets: Curb inlets shall be installed at intersections and at <br /> intermediate points when the gutter flow for the "design storm" <br /> exceeds the value for a given street slope set forth in the table <br /> attached as Appendix C. Valley gutters at intersections will <br /> not normally be allowed. Inlet capacities shall be determined <br /> assuming 50% of the grate waterway openings to be clogged. Add- <br /> itional inlets or special designs may be required in sump areas. <br /> <br />1-09 Manholes: A standard manhole shall be constructed at all pipe <br /> intersections', changes in pipe size, abrupt changes in horizontal <br /> or vertical alignment and at least every 500 feet on straight runs. <br /> Where silting is a possible problem special silt collecting man- <br /> holes may be omitted at the intersection of extremely short later- <br /> als with a main line with specific approval of the City Engineer <br /> when a proper alternate connection is made. <br /> <br />1-10 Outlet Structures, Headwalls, Box Culverts: Outlet structures and <br /> headwalls may be reinforced or gravity type. All reinforced <br /> structures shall use Class A concrete. Maximum bearing value used <br /> for soil without substantiating soils reports shall be 2000 pounds <br /> per square foot, and this shall be reduced when required by the <br /> City Engineer. A minumum equivalent fluid pressure of 33 pounds <br /> per cubic foot shall be used in the design of retaining walls and <br /> this shall be increased when required by the City Engineer. <br /> Standand designs either of the City of Pleasanton, Alameda County <br /> Flood Control and Water Conservation District or the State Division <br /> of Highways may be used without supporting calculations when <br /> applicable, otherwise design calculations shall be submitted. <br /> Loadings shall be as recommended by the American Association of <br /> State Highway Officials. Energy dissipators may be required on <br /> large oulet structures. <br /> <br />]~-11 Junction Losses: Junction losses at manhol~ inlets, and junction <br /> boxes shall be included in all hydraulic calculations. The <br /> following formulas shall be used: <br /> <br />hL = v2 <br /> 2g <br /> <br />hL = 0.5 v2 <br /> 2g <br /> <br />hL = 0.10 v2 <br /> <br />- For 90° Bend <br /> <br />- For 45° Bend <br /> <br />- For straight runs <br /> 1.3 <br /> <br />Note: <br /> <br />Junction losses <br />for angles other <br />than what is shown <br />will be interpolated° <br /> <br /> <br />