(A) General requirements. If, in the judgement of the Commission, a public sanitary sewer is reasonably accessible, the subdivider shall install a complete sanitary sewer system approved by the State Board of Health, including a lateral connection for each lot in the subdivision.
(B) Sanitary sewerage system requirements. Where provided, sanitary sewerage facilities shall connect with public sanitary sewerage systems, and shall be installed to serve each lot to grades and sizes required by approving officials and agencies. Sanitary sewerage facilities (including the installation of laterals in the right-of-way) shall be subject to the specifications, rules, regulations and guidelines of the Health Officer, participating jurisdiction and appropriate state agency.
(C) Individual disposal system requirements. If public sewer facilities are not available and individual disposal systems are proposed, minimum lot areas shall conform to the requirements of Chapter 156 of this code and any ordinance of any participating jurisdiction, establishing lot areas for individual sewerage disposal systems. In this case, sanitary wastes may be disposed of by one of the following methods:
(1) The subdivision may be provided with a complete sanitary sewer system, including a lateral connection for each lot and a package treatment plant, all meeting the approval of the State Board of Health and the State Stream Pollution Control Board; or
(2) The subdivider may provide a private sewage disposal system on individual lots consisting of a septic tank and soil absorption field or other approved sewage disposal system, provided the disposal systems are totaled in accordance with the minimum standards of the State Board of Health and provided that the soil in the subdivision will properly absorb sewage effluent as determined by soil studies and by percolation tests performed in accordance with the procedure prescribed by the State Board of Health or as determined by such other comparable tests approved by the Commission. Regardless of test used, the following shall apply:
(a) An adequate number of tests, as determined by the Commission, to clearly indicate the soil conditions throughout the subdivision shall be made by the subdivider;
(b) The tests shall be performed by a licensed engineer, licensed surveyor or qualified sanitarian;
(c) The location of each test shall be recorded on a map of the subdivision, located on a drawing made to scale;
(d) The results of the tests shall be keyed to the map and certified as being true, correct and performed according to the required procedure by the person performing the tests; and
(e) No lot shall be used as a building site on which a percolation test indicates a time of 60 minutes or more for the water to fall one inch.
(D) Selected design criteria.
(1) Alignment. All sewers shall be laid with a straight alignment between manholes, unless otherwise directed or approved by the City Engineer.
(2) Manhole location. Manholes shall be installed at the end of each line, and at distances not greater than 400 feet for sewers 18 inches in diameter and larger.
(3) Manholes. The difference in elevation between any incoming sewer and the manhole invert shall not exceed 12 inches where required to match crowns. The use of drop manholes requires approval by the City Engineer. The minimum inside diameter of the manholes shall conform to those specified by the City Engineer. Inside drop manholes will require special consideration; however, in no case shall the minimum clear distance be less than that indicated herein. The relationships between intersecting sewer lines shall meet the standards required by the City Engineer. See division (D)(1) above.
(4) Sewerage locations. Sanitary sewers shall be located within street or alley rights-of-way unless topography dictates otherwise. When located in easements on private property, access shall be provided to all manholes. Where sewer lines in private easements cross public street or alley rights-of-way a manhole shall be provided in the rights-of-way where possible. Imposed loading shall be considered at all manhole locations. Not less than six feet of cover shall be provided over the top of pipe in street and alley rights-of-way or three feet in all other areas.
(5) Cleanouts. Cleanouts will not be permitted.
(6) Water supply interconnections. There shall be no physical connection between a public or private potable water supply system and a sewer which will permit the passage of any sewage or polluted water into the potable water system. Sewers shall be kept removed from water supply wells or other water supply sources and structures.
(7) Relation of sewers to water mains. A minimum horizontal distance of ten feet shall be maintained between parallel water and sewer lines. At points where sewers cross water mains, the sewer shall be constructed of cast iron pipe or encased in concrete for a distance of ten feet in each direction from the crossing, measured perpendicular to the water line. This will not be required when the water line is at least two feet above the sewer line.
(E) Sewer mains. If a sanitary sewer system is to be installed, it may be desirable to install sewer mains of a larger size than needed to serve the immediate subdivision. If this occurs, the Commission may recommend that the public utility join with the subdivider in the installation of the sewer system.
(F) Specifications for parts and materials.
(1) The sewage main shall be constructed of Schedule 40 Plastic, equipped with slip joints with locking gaskets. The city must approve the main before installation.
(2) The sewage main fittings shall be constructed of Schedule 40 Plastic, equipped with sip joints with locking gaskets. The city must approve the fittings before installation.
(3) Manholes must be constructed of cement.
(4) Manhole casting specifications.
(a) Manhole frame C.I., Neenah 24 inches (5900-0007) or like, approved by the city before installation.
(b) Manhole lids C.I., Neenah 24 inches (5900-0265) or like, approved by the city before installation.
(c) Risers C.I., Neenah 24 inches, bolt ii rings, approved by the city before installation.
(5) Sewage tapping saddles must have at least one strap that connects it to the main, and it must keep the sewage service line out of the main sewage line. They must be approved by the city before installation.
(6) There shall not be any connects to the sewage lines without the permission of the city prior to starting. All connects that can be made through a manhole should be done, but the permission of the city should be obtained prior to starting.
(7) Handling and storage of materials.
(a) All piping, fittings, manholes, castings and accessories shall be loaded and unloaded by lifting with hoists or skidding in order to avoid shock or damage.
(b) Under no circumstances shall the material be dropped.
(c) Pipe handled on skidways shall not be rolled or skidded against pipe on the ground.
(d) Slings, hooks or pipe tongs shall be padded and used to prevent damage to the exterior of the pipe or internal lining.
(e) If stored, materials should be protected against damage. Pipes shall not be stacked higher than the limits shown in Table 4-2. The pipes shall be stacked in alternating tiers, and the bottom tier of pipes shall be kept off the ground. At least two rows of timbers shall be placed between tiers and chocked. Timbers shall be large enough to prevent contact between pipe in adjacent tiers.
(f) Gaskets for mechanical and push-on joints shall be stored in a cool location out of direct sunlight. Gaskets shall be used on a first in, first out basis. Gaskets shall not come in contact with petroleum products. Bolts shall be handled and stored in a dry location to ensure proper use.
(G) Trench construction, grade and alignment.
(1) Trench construction.
(a) Trench shall be excavated to the depth, width and alignment as specified and shall be in accordance with all regulations as they pertain to safety.
(b) Trench preparation shall advance only as far as stated in the specifications.
(c) Discharges due to de-watering pumping shall be to natural drainage channels, or storm sewers.
(d) Excavated materials shall be placed in a manner that will not hinder the work or endanger workers.
(e) Removal of pavement will be part of trench excavation.
(f) The amount removed shall depend on the width of the trench.
(g) Methods such as sawing, drilling or chipping shall be used to ensure breakage of pavement along straight lines.
(h) Trench width shown in Table 4-2 may be used as a guide.
(i) Trenches shall be of extra width when required for the use of shoring or trenching equipment.
(j) Bell holes shall be provided at each joint.
(2) Alignment and grade.
(a) Sewer mains shall be laid and maintained to lines and grades established by the plans.
(b) Prior to excavation, investigation shall be made to the extent necessary to determine the location of existing structures.
(c) Care shall be exercised by the contractor to avoid damage to existing structures.
(d) When obstructions that exist but are not shown on the plans are encountered, the owner will alter the plans or order deviation in line and grade or arrange for removal of the obstructions.
(e) When crossing existing pipelines or other structures, alignment and grade shall be adjusted as necessary.
(f) All property shall be protected during construction, including trees, shrubs and fences.
(g) Temporary support, adequate protection and maintenance shall be provided in accordance with the specifications.
(h) All properties that have been disturbed shall be restored as nearly as practical to their original condition.
(i) When unsuitable material is found, it shall be removed to a minimum of at least six inches below the bottom of the pipe and replaced with stable fill.
(j) When the bottom of the trench or subgrade is found to consist of unsuitable material to the degree that it cannot be removed, a foundation shall be constructed using piling, treated timber, concrete or other materials, at the direction of the owner.
(k) Appropriate traffic-control devices shall be provided in accordance with federal, state and local regulations.
(H) Pipe installation.
(1) Proper implements, tools and facilities shall be provided and used for the safe and convenient performance of the work.
(a) All pipes, fittings or valves shall be lowered into the trench by means of a derrick, ropes or other suitable tools or equipment with care not to damage the items.
(b) Where practical, the trench should be dewatered prior to the installation of the pipe.
(2) All materials shall be examined carefully for damage and other defects. Any flawed material found shall be marked for inspection by the owner who shall suggest repair or reject the material.
(3) Foreign material shall be prevented from entering the pipe during installation.
(4) As each piece of pipe is laid in the trench, the joint shall be assembled and locked into place using approved backfill.
(5) Any installation requiring polyethylene encasement of ductile iron pipe shall be installed in accordance with ANSI/AWWA C105/A21.5.
(6) New sewer lines shall be installed at least ten feet horizontally from any existing or proposed water line.
(7) Sewer lines crossing water lines shall be laid to provide a minimum vertical distance of at least 18 inches below the existing water line.
(8) Sewer manholes shall be placed at all intersections of piping, or where there is any change in the pipe diameter.
(9) Joint assembly:
(a) Push-on joints shall be assembled in accordance with prevailing city standards; and
(b) Mechanical joints shall be assembled in accordance with prevailing city standards.
(11) Cutting pipe for insertion of valves, fittings or closure pieces shall be done in conformance with all safety recommendations.
(I) Valve and fitting installation.
(1) Before installation, all material shall be inspected for operation and defects.
(2) When sewer lines cross a highway or a railway, the crossing shall be in accordance with all federal, state and local regulations as well as compliance with the regulations set forth by the railroad company.
(3) All lines crossing highways or railways shall be in casing pipe.
(a) The casing pipe shall be six to eight inches larger than the outside diameter of the bells of the carrier pipe.
(b) Carrier pipe shall be pushed or pulled through the completed casing pipe.
(c) Chocks or skids shall be placed beneath the carrier pipe in order to prevent metal-to-metal contact and to help center the carrier pipe inside of the casing.
(d) To avoid transferring earth and live loads to the carrier pipe, the space between the carrier and the casing pipes shall not be completely filled.
(4) Service taps will be allowed only with the use of a saddle so that the service line does not intrude on the inner diameter of the pipe.
(J) Backfilling.
(1) All backfill material shall be free from cinders, ashes, refuse, vegetable or organic matter, boulders, rocks, stones, frozen soil or other material that in the opinion of the owner is unsuitable.
(2) From one foot above the top of the pipe to the subgrade of the pavement, material containing stones up to six inches in diameter in the greatest dimension may be used.
(3) When the type of backfill is not specified tn the plans, the excavated material may be used if it meets the criteria of these specifications.
(4) If excavated material is used as the backfill and there is a deficiency due to rejection of a part thereof, the required amount of sand, gravel or other approved material shall be provided.
(5) Compaction shall be completed in ten-inch lifts to provide proper compaction rates and to avoid problems that result from improper backfill methods.
(Ord. 615, passed 2-22-1999)