Laserfiche WebLink
5.7.3 Recommended alignment within an exclusive storm sewer easement. <br /> <br /> A. Storm sewers placed in easements shall conform to the requirements of Section 2.4.5 <br />B. Storm sewers within easements shall be placed no closer than five feet (5’) measured <br />from the outside edge of the pipe to the edge of an easement, except when adjoining <br />another easement or public right-of-way where the distance may be reduced to two feet <br />(2’). The storm sewer shall be placed in the center of the easement. When the storm <br />sewer easement adjoins a public right-of-way, the easement may be reduced to a <br />minimum of ten feet (10’) and the storm sewer may be aligned close to the right-of-way <br />line, as long as required clearances are met, with specific approval of the City Engineer. <br /> <br /> <br />5.8 STORM SEWER MATERIALS <br /> <br />5.8.1 Storm sewer and culvert pipe shall be precast reinforced concrete pipe, unless specifically <br /> approved by the City Engineer. Concrete pipe shall be manufactured in conformance with the <br /> requirements of ASTM C 76, “Reinforced Concrete Culvert, Storm Drain, and Sewer Pipe,” <br /> current revision. Reinforced concrete pipe shall be Class III or stronger. The design engineer <br /> shall provide for increased pipe strength when conditions of the proposed installation exceed the <br /> allowable load for Class III pipe. All concrete pipe constructed in water-bearing soil or forty-two <br /> inches (42”) in diameter or larger, shall have rubber gasket joints meeting the requirements of <br /> ANSI/ASTM C 443, “Joints for Circular Concrete Sewer and Culvert pipe, Using Rubber <br /> Gaskets”, current revision. Concrete pipe with diameter of less than forty-two inches (42”) may <br /> be installed using pipe with tongue and groove type joint and Ram-nek, or approved equal, as a <br /> joint filler. When specifically approved by the City Engineer, reinforced concrete arch and <br /> elliptical pipe conforming to ASTM C506 and ASTM C507, respectively, current revision, may be <br /> installed in lieu of circular pipe. Reinforced concrete box culverts shall meet the minimum <br /> requirements of ASTM C789, “Precast Reinforced Concrete Box Sections for Culverts, Storm <br /> Drains, and Sewers”, current revision. Pipe joints for arch and elliptical pipe and box culverts <br /> shall be sealed using Ram-nek or approved equal. <br /> <br />5.8.2 Storm sewer outfalls into open channels shall be constructed using corrugated steel pipe. <br /> Corrugated steel pipe shall be manufactured in conformance with the requirements of <br /> AASHTO Designation M-36-82, current revision. Pipe material shall be Aluminized Steel Type <br /> 2, meeting the requirements of AASHTO Designation M-27-79I, current revision, or Pre-coated <br /> Galvanized Steel, AASHTO M-246, 10 mil coating on both sides. All pipe shall have a full <br /> double coating, Type A, in accordance with AASHTO Designation M-190, current revision. Pipe <br /> joints and fittings shall meet the minimum requirements of these specifications and shall have an <br /> O-ring gasket seal meeting the requirements of AASHTO C-361, current revision. (See City of La <br /> Porte Construction Details). <br /> <br />5.8.3 Storm sewer outfalls shall have a slope protection to prevent erosion. Slope protection may be <br /> constructed of slope paving or rip rap. Slope paving shall be four-inch (4”) five (5) sack concrete <br /> with six-inch by six-inch (6” x 6”) welded wire mesh (W14 x W14) or three eighths inch (3/8”) <br /> steel rebar on twenty-four-inch (24”) centers, each way. Rip rap shall be a minimum of six-inch <br /> (6”) broken concrete rubble with no exposed steel or well-rounded stone and shall be a minimum <br /> of eighteen inches (18”) thick. Slope protection texturing shall be required where public access <br /> likely. Refer to the Construction Details for minimum dimensions. <br /> <br /> <br />5.9 ADDITIONAL REQUIREMENTS <br /> <br />5.9.1 Minimum depth of storm sewer (measured to the top of pipe) shall be twenty-four (24”) below the <br /> top of curb or finished grade, whichever is lower. Minimum size storm sewer for main and <br /> inlet lead shall be twenty-four inches (24”). <br /> <br />Stormwater Criteria Page 8 of 10 <br /> <br />