(A) All gravity sewer pipe shall be laid to conform to the prescribed line and grade shown on the drawings by using a laser. The subdivider shall constantly check line and grade of the laser beam and the pipe, and in the event they do not meet the elevations and grades shown on the drawings, the subdivider shall stop the work and notify the developer’s engineer, remedy the cause, and re-lay any pipe installed at improper grade or elevations. Minimum cover shall be four feet from finished grade to the top of the pipe for gravity sewers or forcemain. Special structural protection shall be provided for cases where there is less than minimum cover.
(B) Laying of pipe shall be accomplished to line and grade in the trench only after it has been dewatered and the foundation and/or bedding has been prepared. Mud, silt, gravel, and other foreign material shall be kept out of the pipe and off the jointing surfaces. Dewatering sufficient to maintain the water level at or below the surface of trench bottom or base of the bedding course, shall be accomplished prior to pipe laying and jointing, if not prior to excavation and placing of the bedding. The dewatering operation, however accomplished, shall be carried out so that it does not destroy or weaken the strength of the soil under or alongside the trench. The normal water table shall be restored to its natural level in such a manner as to not disturb the pipe and its foundation.
(C) All pipe laid shall be retained in position so as to maintain alignment and joint closure until sufficient backfill has been completed to adequately hold the pipe in place. The pipe shall be laid up grade from point of connection on the existing pipe or from a designated starting point. The pipe shall be installed with the “female” end upgrade, unless authorized otherwise. When pipe laying is not in progress, the forward end of the pipe shall be kept tightly closed with a temporary plug.
(D) Pipe bedding shall be placed so that the entire length of the pipe will have full bearing.
(E) Plugs for pipe branches, stubs, or other open ends which are not to be immediately connected shall be made of an authorized material and shall be secured in place with a joint comparable to the main line joint. Stoppers may be of an integrally cast breakout design.
(F) No existing pipe shall be connected to a new pipe unless specifically authorized in each instance by the Village Engineer. Storm drains and drain tiles shall not be connected to a wastewater sewer.
(G) The subdivider shall install service sewers (laterals) where and as shown on the drawings. Excavation, backfill, restoration of surfaces, and the laying of service sewers (laterals) shall be the same as for the mainline gravity sewers. The subdivider shall connect the service sewers (laterals) to the mainline gravity sewer by either a service riser and service wye, only a service wye, or at a manhole stub. If required, the subdivider shall also make the four-inch diameter building sewer connections to the six-inch diameter service sewers (laterals).
(H) Existing sewers severed during any excavation shall be repaired by replacing them with ductile-iron pipe of the same inside diameter. The ends of the ductile-iron pipe shall be joined to the existing pipe on each side of the trench by the method illustrated on the drawings.
(I) Pipes shall be jointed as recommended by the pipe manufacturer. Dissimilar pipes shall be jointed with suitable adapter couplings and concrete encasement, unless otherwise authorized by the developer’s engineer.
(J) (1) Where the depth of the sewer invert is greater than seven feet below the surface of the ground, a service riser shall be constructed to an elevation of seven feet below the ground elevation. In some locations, seven feet of depth may be too shallow to serve basements. As other locations wyes may have to be installed so that the spur is at right angles to the vertical plane through the centerline of the sewer.
(2) The subdivider shall be responsible for closely checking the basement elevations along with the distance from the new mainline sewer to the building to be served and shall install the spur of the wye, or the top of the riser, or the end of the lateral (whichever applies) at a low enough elevation to permit the six-inch diameter service sewer to be installed at a one-eighth of an inch per foot grade and still have the flowline of the upstream end of the building sewer at least one foot below the basement elevation. In no case shall the top of the riser be less than seven feet below the ground surface.
(3) The service riser shall be constructed with a six-inch wye placed to receive the six-inch riser or lateral. The riser pipe shall extend to the elevation as hereinabove determined. The wye, or wye and riser combination, shall be installed and bedded as shown on the drawings.
(4) Six-inch laterals shall be constructed from the tee branch and riser to five feet beyond the property line of the lot to be served, or to the location shown on the drawings, and shall terminate with a manufactured temporary plug. In many cases these laterals will have to be constructed across streets, alleys, sidewalks, and easements to reach the property line.
(5) Prior to backfilling, the subdivider shall place a two-inch by two-inch stake at the end of the riser or lateral, perpendicular to the horizontal plane through the center line of the pipe and extending at least 18 inches above the top of the pipe. Care shall be taken while backfilling to insure the stake remains vertical. The purpose of said stake is to serve breakage of the pipe during house hook-ups. After backfilling, a second two-inch by two-inch stake having a minimum length of 18 inches shall be driven into the ground surface at the end of the riser or lateral as a visual indicator of the location of the service. The stake shall extend six inches above the ground surface and shall be painted with orange and red fluorescent paint.
(K) Whenever shown on the drawings, the subdivider shall connect service sewers and risers (six-inch diameter) to the new mainline sewers by core drilling a six-inch diameter hole in the pipe wall, installing a cast iron tee saddle on the sanitary sewer and connecting the service sewer to the tee. Care must be taken in ordering tee saddles so they are compatible with both the mainline sewer pipe type and the brand of service sewer pipe being used.
(L) (1) The base section shall be placed on a compacted granular bedding not less than six inches thick and extending to the limits of the excavation. The bedding shall be smooth and level to assure uniform contact and support of the manhole base. The manhole base and fillet may be cast monolithically with the bottom barrel section of the manhole.
(2) All lift holes shall be completely filled with non-shrink grout and the exterior coated with a layer of waterproofing paint prior to backfilling. All void spaces on the inside and outside of manhole joints shall be filled with non-shrink grout.
(3) For manhole joints that will be subject to a constant hydrostatic pressure, an external rubber seal with metal bands shall be placed around the joints in the barrel section.
(4) Blockouts (within the manholes at the fillets) used to install the rubber pipe gaskets shall be filled with concrete to the centerline of the influent and/or effluent piping.
(5) After all sewers have been connected to the manhole, a concrete fillet shall be constructed in the bottom of the manhole as shown in the details on the drawings. Placement of the fillets shall be prior to placement of the manhole flat tops and/or frames and grates.
(6) Castings placed on concrete or masonry surfaces shall be set in full mortar beds. Castings shall be set accurately to the finished elevation so that no subsequent adjustment will be necessary.
(7) Manholes shall be famished with a one-half-inch diameter pipe nipple ten inches long with a cap extending through the manhole wall and located at the top of the sewer pipe or by an alternative method authorized by the Village Engineer to assist in determining the level of the ambient water table.
(Ord. 97-7, passed 7-1-1997, § 5.18)