(a) Materials.
(1) General. Unless otherwise specified, all materials used in the work shall conform to the requirements of the current specifications of the American Society for Testing Materials, and shall be tested in accordance with the current specifications or current methods of testing of the American Society for Testing Materials, where specifications and methods of testing have been adopted, revised or proposed for such materials. It is understood that wherever the word "current" is used relative to the specifications and methods of testing of the American Society for Testing Materials, it refers to the standard or tentative standard of that Society bearing the latest date.
No material shall be used until it has been inspected and approved on the site of the work. When required by the Engineer, any or all materials entering into the construction of any work under this contract shall be tested by a reputable testing laboratory at the owner's expense. Such inspection shall not relieve the material or workmanship which may have passed the Engineer and shall be at all times liable to rejection when discovered, until the final completion of the work.
(2) Portland Cement. Portland Cement furnished or used shall conform to the following requirements:
A. Portland Cement for general construction purposes shall conform to the requirements specified for Type I of the "Standard Specifications for Portland Cement", A.S.T.M. Designation: C 150.
B. Portland Cement - High Early Strength shall conform to the requirements specified for Type III of the "Standard Specifications for Portland Cement", A.S.T.M. Designation: C 150.
C. Portland Cement - Air-Entraining shall conform to the requirements specified for Type IA of the "Tentative Specifications for Air- Entraining Portland Cement", A.S.T.M. Designation: C 175.
Portland Cement shall be delivered to the site of the work in unbroken cloth or paper sacks, with the name and brand of the manufacturer and the type under these specifications, marked thereon.
Cement shall be stored in such a manner as to fully protect it from moisture and exposure to the weather. Cement which has become caked, partially set or otherwise deteriorated or contaminated shall not be used in the work.
(3) Mortar sand. Mortar sand shall be composed of clean, hard, durable particles of stone, uncoated with clay or organic matter and free from lumps of these materials. It shall conform to the following specific requirements for grading:
Sieve Passing No. | Percent |
4 | 100 |
16 not less than | 95 |
100 not over | 10 |
and Clay and Silt, by weight not over | 3 |
(4) Concrete sand. Concrete sand shall be composed of clean, hard, durable particles of stone uncoated with clay or organic matter and free from lumps of such materials. It shall conform to the following requirements for grading:
Sieve Passing No. | Percent |
3/8 | 100 |
4 | 95 to 100 |
16 | 45 to 95 |
50 | 10 to 30 |
100 | 2 to 10 |
and Clay and Silt, by weight not over | 3 |
(5) Coarse aggregate. Coarse aggregate for concrete work may be broken stone, blast furnace slag or gravel. It shall be clean, free from loam, clay, silt, organic matter or other injurious impurities. Stone shall be hard limestone, trap rock or granite. Slag shall be air-cooled blast furnace slag, clean, sound, uniform in density and free from thin, elongated or glassy pieces and must weigh not less than 1800 pounds per cubic yard. Gravel shall be clean silica, screen-washed, sound and hard and acceptable to the Engineer. Any material used shall be so placed when delivered that it will not become contaminated by earth, grass or other foreign substance. For use in concrete pipe or in work less than eight inches thick, all aggregate shall pass a one-inch screen and be retained on a one-quarter inch screen. For larger work the aggregate shall range from a size which will pass a two-inch screen and be retained on a one-quarter inch screen. The voids in loosely placed aggregate shall not exceed forty-five percent.
(6) Cinders. Cinders shall be only those from a power plant and not those from stoves or household furnaces. They shall be black and free from clinkers, unburned coal, glue dust and rubbish.
(7) Water. All water required in the execution of this contract must be provided by the owner at his own expense. Water containing sewage, clay, oil or filth must not be used.
(8) Brick. Brick used in the construction of catchbasins, manholes, inverts, junctions and sewers shall be smooth, sound, tough, with straight sharp edges, flat surfaces and shall be uniform in quality, cross-section and dimensions. If made from surface clay or fire clay, they shall be burned hard entirely through the brick. If No. 2 shale brick is used, it shall be thoroughly vitrified, and shall show not to exceed eight percent absorption when kiln dried then immersed in water for twenty-four hours. All brick shall be thoroughly sprinkled with water before laying. All sewer brick shall have a width of four inches, a length of eight and one-half inches and a depth of two and one-half inches, three inches or three and one-half inches. Lugged brick, cored brick or brick having recesses or openings extending through or partly through the body of the brick may not be used.
(9) Vitrified sewer pipe. All vitrified sewer pipe, slants and specials shall be of the bell and spigot pattern, salt-glazed, circular, vitrified earthenware made from shale or fire clay, free from fire-checks, blisters or other imperfections.
Unless otherwise specified, all pipe, slants and specials shall conform to the requirements specified in the "Standard Specifications for Standard Strength Clay Sewer Pipe", A.S.T.M. Designation: C-13.
Where specified or called for in the plans, all pipes, slants and specials shall conform to the requirements specified in the "Standard Specifications for Extra-Strength Clay Sewer Pipe", A.S.T.M. Designation: C-200.
(10) Lumber. Lumber for sheeting, sheet piling, forms, bracing or bridging must be of good quality and of a size and strength suitable for properly protecting the work and workman from danger, and for securing the best possible conditions for construction. Any material deemed unsuitable or unsafe by the Engineer must be removed at once from the work. Lumber for grillage under the foundation of the sewer must be of good quality, hardwood lumber, sound, square-edged and free from warp, loose knots or other defects.
(11) Reinforcing steel. Reinforcing steel shall conform to all the requirements of "Standard Specifications for Billet Steel Bars for Concrete Reinforcement", A.S.T.M. Designation: A-15, or to the requirements of "Standard Specifications for Rail Steel Bars for Concrete Reinforcement", A.S.T.M. Designation: A-16. All reinforcing bars shall be deformed, in conformance with the requirements of "Tentative Specifications for Minimum Requirements for the Deformation of Deformed Steel Bars for Concrete Reinforcement", A.S.T.M. Designation: A 305. Welded steel wire fabric shall conform to all the requirements of "Standard Specifications for Welded Steel Wire Fabric for Concrete Reinforcement", A.S.T.M. Designation: A-185. All reinforcing steel shall be of new stock and free from scale, rust, oil, paint or coatings of any kind.
(12) Manhole and catchbasin castings. Castings for manhole caps and covers and for catchbasin tops shall conform in design to the standard plans on file in the office of the Engineer. All castings shall be true to pattern and free from cracks, gas holes, flaws and excessive shrinkage. Surfaces shall be free from burnt-on sand and shall be reasonably smooth. Runners, fins, risers and other risers and other cast-on pieces shall be removed. All castings shall be tough and of even grain. All parts of castings shall be thoroughly coated with a suitable asphaltum or other impervious preparation as may be acceptable to the Engineer. All castings shall be commercially machineable and, in case of manholes and catchbasins, the frame and cover shall, if necessary, be so machined that it will be impossible to rock the cover after it has been sealed in the proper position in the frame.
(13) Cast iron manhole steps. Manhole steps furnished under these specifications shall conform in design to the standard plans on file in the office of the Engineer. They shall be true to pattern and surfaces shall be free from cracks, flaws, fins and burnt-on sand, and shall be reasonably smooth. They shall be coated with a suitable asphaltum or other impervious preparation acceptable to the Engineer. Cast iron for manhole steps shall conform to all the requirements of Class 30 of "Standard Specifications for Gray Iron Castings", A.S.T.M. Designation: A 48.
(14) Cast iron pipe. Cast iron pipe and fittings shall be bell and spigot pattern, flanged or standardized mechanical joint, as specified or called for on the plans.
All cast iron pipe and fittings shall conform to the "Standard Specifications of the American Water Works Association" or to the requirements of "Federal Specifications for Cast Iron Pipe", No. WW-P-421. All cast iron pipe shall be of the class, weight or type as called for on the plans or otherwise specified.
(15) Joining material for bell and spigot cast iron pipe. Yarn for lead joints shall be of the best quality jute or oakum, closely twisted in one piece for each joint. Lead for pipe joints shall be pure, soft and malleable, free from dross and capable of being caulked into the joints without cracking.
(16) Concrete pipe.
A. Nonreinforced concrete pipe. Concrete pipe furnished or used under this classification shall conform to the requirements of the "Standard Specifications for Concrete Sewer Pipe", A.S.T.M. Designation: C 14.
B. Reinforced concrete sewer pipe. Concrete pipe furnished or used under this classification shall conform to the requirements of the "Standard Specifications for Reinforced Concrete Sewer Pipe", A.S.T.M. Designation: C 75.
C. Reinforced concrete culvert pipe. Concrete pipe furnished or used under this classification shall conform to the requirements of the "Standard Specifications for Reinforced Concrete Culvert Pipe", A.S.T.M. Designation: C 76.
(Ord. 538-55. Passed 4-4-55.)
(17) Jointing material for concrete pipe. All storm sewer and sanitary sewer pipe shall have premium joints.
(b) Alignment, Grade and Design.
(1) General. All sewer pipe shall be laid and maintained to the required lines and grade, with "Y" branches, "T" Branches, slants and openings left for manholes at the required locations and with all joints centered and all spigots home. All necessary lines and grades shall be given to the owner by the Engineer within a reasonable time after notice by the owner of the time and place he intends to work.
(2) Grade bars. The owner shall furnish all material and labor to set grade bars every fifty feet. Every pipe shall be laid at each end to line and grade indicated by a line drawn between the grade bars, by using a rod or pole of fixed length as a gauge between the working line and the pipe in the trench. A plumb bob shall be used to check the line of pipe. If the grades are flat and the Engineer so orders, the owner shall place intermediate bars between those set at the stakes of the Engineer, to avoid sag in the working line,
(3) Design. The storm frequency design criteria for storm sewers shall be as follows:
Frequency (years) | |
Commercial, industrial, apartments | 10 |
Residential | 5 |
(Ord. 11-64. Passed 4-21-64.) | |
(c) Excavation and Preparation of Trench.
(1) Width. The minimum width of unsheeted trench shall be at least one foot wider than the outside diameter of pipe at the spring line. The maximum clear width of trench shall be not more than two feet greater than the outside diameter of the pipe at the spring line except by consent of the Engineer.
(2) Depth. The depth of the excavation for the sewer or other structure herein specified shall be such that they can be built to proper grade, due allowance being made for the bottom masonry work and timber foundations. Where grillage is used, the bottom excavation shall be level transversely and have the same longitudinal inclination as that of the sewer. In order to place the longitudinal stringers or sleepers, only enough excavation shall be done to place the same in position, the earth between such sleepers in no case is to be excavated deeper than the bottom of grillage planks. When no grillage is used, the bottom excavation shall be such as to exactly fit the wooden invert, the outside contour of the masonry, or be left horizontal transversely. Should the owner excavate beyond the limits herein specified, the space so caused alongside or below the masonry of the sewer shall be completely filled with masonry, if such is used in the sewer construction, or with class "C" concrete and the cost of such masonry or concrete shall be included in the contract unit price for the sewer complete in place.
(3) Blasting procedure. Blasting for excavation will be permitted only after securing the written approval from the Chief of Police who shall fix the time during which blasting may be done and what protective measures must be used to insure safety of adjacent property. The owner shall be responsible for any damage resulting from blasting. The owner's method of procedure relative to blasting shall conform to State Laws and to local City ordinances.
(4) Braced and sheeted trenches. Wherever necessary to prevent caving, excavations in sand, gravel, sandy soil or other unstable material shall be adequately sheeted and braced. Where sheeting and bracing is used, the trench width shall be increased accordingly. Trench sheeting shall remain in place until the pipe has been laid and the earth around it compacted to a depth of one foot over the top of pipe. Sheeting left in the trench by order of the Engineer will be paid for at price bid per 1000 (M) feet.
(5) Drainage. The owner shall, when ordered by the inspector, construct tight bulkheads across the trench and provide pumps suitable for the removal of any water which may be encountered or which may accumulate in the trenches. In no case shall the water be permitted to rise upon or flow through the sewer until permitted by the inspector.
(6) Existing watercourses. The owner shall, at his own expense, provide for the protection and securing of a continuous flow in open watercourses, ditches or pipes encountered during the progress of the work and shall repair any damage that may be done by reason of them.
(7) Road surfaces, curbing, driveways and sidewalks. The owner shall remove all pavements, road surfaces, curbing, driveways and sidewalks within the lines of excavation. The owner shall make all cuts by a channeling machine, hand operated pneumatic tools or by such other methods as will furnish a clean cut in the pavement and base without undue shattering. All concrete curbing, driveways or sidewalks within the lines of excavation shall be broken up and removed by the owner. All such work as above designated shall be done at the owner's expense and in accordance with the rules and regulations of the City in which the work is done The use of a "pear" or weight dropped on the pavement for breaking will not be allowed except by written permission of the Engineer.
(8) Excavation by machine or by hand. The use of excavation machinery will be permitted except in places where the operation of the same will cause damage to trees, buildings or existing structures above or below ground; in which case hand methods shall be employed. All work must be done in open trench, no tunneling, boring or forcing will be allowed without a special written permit from the Engineer. The excavated material must be so piled as not to endanger the work, obstruct driveways and sidewalks nor interfere with proper drainage.
(d) Laying Vitrified Pipe.
(1) General. All vitrified pipe for use in sanitary or storm sewers shall conform to the specifications for vitrified pipe in subsection (a)(9) herein. Unless otherwise specified or called for on the plans, all vitrified pipe shall be "standard strength", A.S.T.M. Designation C-13.
All vitrified pipe shall be carefully laid to the lines and grades given by the Engineer, without offsets or uneveness at the joints. Grades shall be taken from established batter boards and a "top line", and the owner shall always maintain the "top line" for a distance covering three grade stakes, and shall also maintain three adjacent batter boards in place. A straight planed measuring pole, about one and one-half inches square, with an iron bracket on the bottom, shall be furnished by the owner at each place where pipe laying is in progress, together with strong "top line" cord and plumb bob. All pipe shall be laid with bells uphill.
(2) Joints. Unless otherwise specified or called for on the plans, all vitrified pipe shall be joined with precast bituminous joints, made in the following manner:
Each pipe shall be fitted with a die-cast tapered collar of an approved bituminous compound on the spigot end of the pipe, and a die-cast lining or ring of similar compound in the socket of the pipe. The collar and ring shall be of such size as to assure a tight fit when the spigot is shoved firmly into the socket portion of the pipe. All pipe must be dry and clean when the lining and collar are cast, and the compound must be poured at a temperature high enough to procure proper adhesion to the pipe.
All collars and rings shall be inspected before the pipes are laid, and no pipe shall be used if either collar or ring shows any void or unfilled space. No jute or other caulking material will be permitted.
When laying the pipe, the lining and collar shall be painted with an adhesive or solvent which shall cause their surfaces to become plastic or tacky and, when the pipes are shoved firmly together, solvent, congeal and become one homogenous body. The collar and ring shall be free from any foreign material which will prevent proper adhesion of the bituminous surfaces forming the joint. The die-cast bituminous joint shall be that manufactured under the name of "Slipseal", or an approved equal.
(3) Construction; single pipe sewers. In earth excavation, unless otherwise specified or called for on the plans, the bottom of the trench shall be excavated to fit the outside periphery of the lower quarter of the pipe, with holes being dug for the bells, and the pipe having full bearing on the bottom of the trench throughout its length. Should the trench not be excavated neatly, all space below the pipe must be filled with Class "C" concrete, extending up around the sides of the pipe so that the lower third of the pipe is supported its entire length, and the cost of such concrete bedding shall be included in the contract unit-price for the sewer complete in place.
In no case shall material be placed under the bell to secure proper grade.
In case of eighteen-inch pipe or larger, a suitable device shall be used to maintain the pipe in a horizontal position while entering the spigot into the bell of the preceding pipe.
In rock, shale or any unyielding material, or where called for on the plans or when ordered by the Engineer, the bottom of the trench shall be excavated at least three inches below the bottom of the pipe, and the pipe shall then be bedded in Class "C" concrete extending up around the sides of the pipe so that the lower third of the pipe is supported its entire length. Where ordered by the Engineer or where specified or called for on the plans, the entire pipe shall be encased in Class "C" concrete. Such concrete encasement shall have minimum dimensions of three inches below and above the outside of the pipe, and extending laterally to the walls of the trench as excavated. Payment for such concrete bedding or encasement shall be made at the contract unit price for concrete bedding. Care shall be taken to prevent the precast bituminous joints from coming into contact with the fresh concrete until after they have been joined.
The trench space each side of the pipe and for a distance of twelve inches above the top thereof shall be backfilled with suitable fine earth, slag or bank sand and thoroughly compacted before any backfilling by machinery is allowed.
The draining of the trench shall be so effected that no water can run through newly laid pipe, nor accumulate in the trench until after the concrete has thoroughly set. All concrete work shall be set up hard before any backfilling work is started.
In no case shall more than 200 feet of trench be opened in advance of pipe laying operations, unless ordered by the Engineer.
All sewers shall be tightly closed at open ends at the completion of each day's work.
(e) Laying Concrete Pipe.
(1) General. All concrete pipe for use in sewers shall conform to the specifications for concrete pipe in subsection (a)(16) herein and shall be of the class or type called for on the plans, or otherwise specified.
(2) Joints. Unless otherwise specified or called for on the plans, all concrete pipe shall be joined with an approved plastic bituminous jointing compound as specified in subsection (a)(17) herein.
(3) Construction; single pipe sewers. Except as otherwise specified herein, concrete pipe shall be laid in accordance with specifications for vitrified pipe in so far as the same may be applicable. Satisfactory means shall be used to hold the pipe in line while the pipes are being joined, and due precaution shall be taken to insure that the spigot end of the pipe being laid is pushed home into the groove of the preceding pipe. A derrick with an approved hoistening lift and hook shall be used to lower concrete pipe into the trench. In earth excavation, unless otherwise specified or called for on the plans, the bottom of the trench shall be nearly formed to fit the contour of the pipe. Should the trench not be excavated neatly, all space below the pipe must be filled with Class "C" concrete, extending up around the sides of the pipe so that the lower third of the pipe is supported its entire length, and the cost of such concrete bedding shall be included in the contract unit price for the sewer complete in place.
In rock, shale or any unyielding material, or where called for on the plans, or where ordered by the Engineer, the bottom of the trench shall be excavated at least three inches below the bottom of the pipe, and the pipe shall then be bedded in Class "C" concrete extending up around the sides of the pipe so that the lower third of the pipe is supported its entire length. Payment for such concrete bedding shall be made at the contract unit price for concrete bedding set forth in the proposal.
Tongue and groove pipe shall be laid with the groove end upstream. The groove end of the first pipe shall be thoroughly cleaned and a layer of bituminous jointing compound applied to the lower half of the groove. The tongue end of the second pipe shall then be inserted into the groove end of the first pipe and shoved home. Sufficient jointing compound shall be used to cause the compound to be squeezed out on the interior and exterior surfaces of the pipes when the pipes are shoved together, and all of the angular space of the joint must be completely filled. The joints shall be troweled smooth, on both interior and exterior surfaces of the pipe, throughout their circumference. In applying the bituminous jointing compound, no admixtures of any kind, such as cement or sand, shall be added to or mixed with the compound. The Compound shall be prepared or mixed strictly in accordance with the manufacturer's directions. Proper precautions shall be taken to prevent water, mud, fresh concrete, or other foreign substances from coming into contact with the jointing compound during jointing operations. All pipe joints must be dry when the compound is applied.
Previous to being lowered into the trench, each pipe shall be carefully inspected and those not meeting the specified requirements shall be either destroyed or immediately removed from the site of the work. Pipes having minor defects not sufficiently serious to cause rejection shall be so laid as to bring such defects in the top half of the sewer. No pipe shall be laid within ten feet of the machine excavating the trench nor within forty feet of any place where blasting is being done, The trench space each side of the pipe, and for a distance of twelve inches above the top thereof, shall be backfilled with suitable fine earth, slag or bank sand and thoroughly compacted before any backfilling by machinery is allowed.
(f) Dual Sewer Construction. In the construction of dual sewers, the sanitary and storm sewers shall be constructed as above specified for vitrified pipe and concrete pipe, or as shown on the plans. The sanitary sewer trench outside the pipe shall be completely filled with Class "C" concrete, with a minimum of three inches of concrete below the bottom of the pipe, and a minimum of six inches of concrete on each side of the pipe, and extending up to the bottom of the storm sewer. The storm sewer pipe shall be laid on a cradle of Class "C" concrete, with a minimum of three inches below the bottom of the pipe, and extending up around the sides of the pipe to the limits shown on the plans. If the sanitary or storm sewer trench is excavated below or beyond the limits above specified, the entire space so excavated shall be filled with Class "C" concrete.
In dual sewer construction, the sanitary and storm sewers shall be laid with a horizontal distance of eight inches between the outsides of the pipe barrels.
The sewer trench shall be backfilled with fine earth, slag or bank sand of thoroughly compacted, to a height of twelve inches above the top of the storm sewer, before any backfilling by machinery is allowed.
In placing concrete cradles or fill, the methods used shall be such as to prevent mud, earth, clay or other foreign materials from becoming mixed with the concrete.
In no case shall "dry-mix" concrete be placed in the trench without permission of the Engineer.
The cost of concrete bedding or encasement for dual sewers shall be included in the contract unit price paid for sewers, and no additional compensation will be allowed for this item.
(g) Backfilling.
(1) Extent of backfill. The backfilling includes all backfilling, ramming, puddling or rolling as required, the regrading of adjacent disturbed areas, the replacing of drains and other surface and subsurface structures, the placing and maintaining of temporary sidewalks and driveways, furnishing of suitable backfill material if necessary, reseeding lawns and replacing trees and shrubbery damaged by the owner and all appurtenant work incidental thereto.
(2) Backfill material. Only fine earth, slag or bank sand shall be used for backfilling along the sides of the sewer, and to a height of twelve inches over the top of the sewer. Should, in the opinion of the Engineer, the material excavated from the trench be unsuitable for backfilling immediately over the sewer, the owner shall, at his own expense, secure suitable material from other sources. The backfilling material shall be brought up evenly on both sides of the sewer and thoroughly compacted by tamping or ramming before any dumping from cars or buckets is permitted.
All backfilling must be laid in horizontal layers, of a depth required by the Engineer, and thoroughly compacted by methods satisfactory to the Engineer. No pieces of rock larger than one cubic foot in volume shall be used in backfill, and all rock particles used in backfill shall be entirely surrounded by fine material. If ordered by the Engineer, the entire trench shall be puddled by flooding with water from a fire hose or conducted along the sewer trench by means of a ditch excavated for that purpose, or by addition of water during backfilling.
No backfilling shall be made during freezing weather except by permission of the Engineer, and no fill shall be made when the material already in the trench is frozen, nor shall frozen material be used in backfilling.
(3) Sand backfill. Where ordered by the Engineer, the excavated material shall be removed from the site of the work and bank sand containing not more than ten percent by weight of loam or clay and free from all deleterious or objectionable material shall be used for backfilling. If required, this sand backfill shall be compacted by tamping in layers of not more than six inches, or by flooding, as may be directed by the Engineer. Sand for backfill, when ordered by the Engineer, will be paid for at the contract price set forth in the proposal.
(h) Disposal of Surplus Excavated Material. All surplus excavated material shall be removed and deposited upon lands abutting the improvement if such fill is requested by the property owners If no filling of abutting property is desired, the owner shall dispose of such surplus wherever he can arrange for rights to fill.
(i) Drainage of Trenches. The sewer trench must in all cases be kept substantially free from storm, surface and subsoil water or sewage, so that all masonry and joints may have ample time to set and harden. No joints shall be made under water. If necessary to accomplish this, in the opinion of the Engineer, the owner shall fill the bottom of the trench with a three-inch layer of crushed slag or stone screenings and install a tile underdrain, embedded on all sides in not less than three inches of crushed slag or stone screenings. All joints of this drain shall be covered with strips of burlap or other cloth of proper porosity. This work shall be paid for at the price bid for the same only when installed upon the written order of the Engineer.
(j) Manholes. All manholes shall be built in accordance with construction plans on file at the office of the Engineer. They shall be built of two and one-half by four by eight and one-half inches shale brick laid in Portland Cement mortar with bricks arranged radially as headers, forming a wall nine inches thick. In deep manholes the wall shall be thirteen inches thick below a point twelve feet from the surface. All brick composing manholes shall be laid in full mortar beds with no mortar joint appearing on the inner surface of the manhole exceeding three-eighths of an inch thick.
The top of the walls of manholes shall be properly leveled off with mortar so as to form a flat surface upon which the cast iron manhole ring is to rest and the manhole shall be carried to proper height above the sewer.
The entire outer surface of manholes shall be plastered with a smooth coating of Portland Cement mortar at least one-half inch in thickness.
The owner shall furnish and set in mortar, upon the top of each manhole, a cast iron manhole ring and cover, ventilated or solid as required, circular in form and cast with the word "sewer" in raised letters. Unless otherwise specified, or shown on the plans, the design, dimensions and weight of the manhole ring and cover shall conform with the standard plans on file in the office of the Engineer.
Cast iron steps, as specified in subsection (a)(13) herein, shall be built into each manhole and shall be continued downward along the interior side of the manhole to a level three feet above the bottom of the sewer. Such steps shall be built into the brick work in a manner satisfactory to the Engineer and shall be spaced not more than fifteen inches apart.
(k) Drop Manholes. Where shown on the plans, drop manholes of the design shown shall be constructed. Drops shall be encased in concrete to the full dimensions shown and the cost of such concrete encasement shall be included in the contract unit price for the manhole, complete in place.
(l) Catchbasins. Catchbasins shall be built in accordance with the plans for the same on file in the office of the Engineer. Brick used in constructing them shall be of shale as specified for manholes.
Unless otherwise specified, or shown on the plans, the design, dimensions and weight of catchbasin covers shall conform with the standard plans on file in the office of the Engineer.
The catchbasins and connections shall be cleaned out before final acceptance of the work. The owner shall test the catchbasin with water when so directed by the Engineer.
(m) Inlets. Inlets shall be built in accordance with the standard plan on file in the office of the Engineer. The cover shall be the same as used on catchbasins, unless otherwise specified.
(n) Bulkheads. Bulkheads shall be constructed by the owner at such locations along the sewers as shown on construction plans. They shall be built of brick masonry, nine inches thick, unless otherwise specified.
(o) Mortar. Cement mortar used in brick masonry, stone masonry, foundations and all underground construction, unless otherwise specified, shall be composed of one part Portland Cement and three parts sand. Mortar for grouting shall be composed of one part Portland Cement and two parts sand.
The ingredients must be proportioned by measurement and not by estimation. They must be thoroughly mixed dry in a suitable tight box, after which the proper quantity of clean water shall be gradually added and then hoed or worked until a uniform mixture is secured. No greater quantity of mortar is to be prepared than is required for immediate use, and any that has set shall not be retempered or used in any way.
No lime or other admixtures of any description shall be used unless so specified or permitted by the Engineer.
(p) Concrete.
(1) General. Concrete shall consist of a mixture of Portland Cement, aggregates and water, proportioned in accordance with the requirements of this specification.
(2) Proportions. In proportioning concrete materials, one bag (sack) of cement shall be considered as being one cubic foot volume and ninety-four pounds weight.
Total maximum water shall be considered as that including added water and absorbed (surface) water in the aggregates.
Cement shall be measured by weight and shall be weighed on a balance or scale separate from those used to weigh the other ingredients.
Aggregates shall be measured by weight. Batch weights shall be based on surface-dried materials and shall be corrected to take into account the weight of surface water contained in the aggregates. Water shall be measured by volume or weight. Concrete shall be of two classes, Class "A" and Class "C", and shall be proportioned as follows:
Class "A" | Class "C" | |
Maximum water, gallons per bag of cement | 6-3/4 | 8 |
Minimum cement, bags per one cubic yard of concrete | 5-3/4 | 4-1/2 |
Minimum compressive strength, pounds per square inch at twenty-eight days | 3,000 | 2,000 |
Proportion by volume, cement to total aggregate | 1 to 5-1/4 | 1 to 7 |
The proportions of fine and coarse aggregates shall be such as to produce the maximum density consistent with proper workability.
Class "A" concrete shall be used for all retaining walls, culverts, special structures, manhole and catchbasin base slabs, and where otherwise specified or shown on the plans.
Class "C" concrete shall be used for all sewer pipe bedding or cradles, concrete filling and where otherwise specified or shown on the plans.
(3) Mixing. All concrete shall be thoroughly mixed in a batch mixer of approved type for at least one and one-half minutes. By permission of the Engineer, a hand mixing may be done in case of emergency or when small quantities of concrete are required and where the use of a mixer is impracticable. The use of "ready-mixed" concrete will be permitted, providing it conforms with all the specifications for concrete contained herein. Concrete so mixed must be mixed, handled and transported so as to cause no segregation of materials when deposited, and shall be mixed not to exceed one hour before placing, unless otherwise permitted by the Engineer. The use of concrete, cement or mortar which has been partially hardened or set will not be permitted.
(4) Forms. Forms of substantial material shall be erected and removed by the owner, and the cost of the same shall be included in the contract price per cubic yard of concrete. All material used for facing against the concrete shall be surfaced and shall be securely held to line by timbers or studding so that no bulging or spreading results from the pouring of the concrete. When required by the Engineer, forms for surfaces of concrete to be exposed in the finished work shall be surfaced with Masonite, Prestwood or plywood. Forms shall be tight so as to prevent water and cement from escaping. Bolts or tie rods shall be used to tie forms together and shall be so made and placed that they will leave no metal within one inch of the surface of concrete. Wiring of forms will be allowed only by permission of the Engineer.
(5) Placing concrete. Earth foundation beds shall have all loose material removed and shall be inspected by the Engineer before any concrete is placed. When water collects in the excavation, it shall be removed before any concrete is placed therein. When there is a continuous flow of water into the excavation, a power-driven pumping unit, of approved design, shall be provided.
Concrete shall be handled from the mixer to place as rapidly as practicable and in a manner that will prevent segregation. Concrete shall not be dropped from a greater height than six feet. The concrete shall be thoroughly spaded against the forms or vibrated with mechanical vibrators, as the Engineer may direct. All reinforcement shall be carefully and accurately set and rigidly held in place. Construction joints shall be scrubbed with wire brushes or cleaned with a steam jet, and well grouted before adding new concrete.
(6) Work in freezing weather. Unless otherwise specified, concrete when deposited shall have a temperature of not less than fifty degrees Fahrenheit, nor more than 115 degrees Fahrenheit. In freezing weather, suitable means shall be provided for maintaining the concrete at a temperature of forty-five degrees Fahrenheit for a period of not less than seven days. Methods of heating shall be subject to approval of the Engineer.
Any concrete which may be damaged by frost action shall be replaced by the owner at his own expense.
(7) Protection and curing. All concrete shall be protected and shall be properly cured by sprinkling or by covering with wet burlap or cotton mats, sisalkraft paper or 100 percent sulphate Kraft paper cemented with a suitable bituminous material for a period of not less than seven days, unless otherwise permitted by the Engineer.
(q) Branch Connections and Risers. Vitrified Y-branches, of the size specified, shall be installed at the locations shown on the plans, or as directed by the Engineer. Where concrete pipe is used for the main sewer construction, vitrified pipe "Y" saddle slants shall be used. All Y- branches and slants shall be firmly supported by a fill of Class "C" concrete, extending from the bottom of the sewer trench to a point three inches above the hub of the spur of the Y-branch or slant. Openings at the outer end shall be closed with vitrified stoppers and sealed with an approved bituminous compound. When required, on account of the depth of the sewer, branches shall be built up vertically with vitrified riser pipes to a point at least nine feet below the top of the curb or ground surface, using bends wherever necessary. The riser pipes shall be recessed into the bank of the sewer trench and encased with Class "C" concrete for their full height. The cost of concrete encasement for risers, and the cost of concrete supports for Y-branches and slants, shall be included in the contract unit price for those items. All material and workmanship shall conform to the specifications for vitrified pipe sewers.
(r) Service Curb Connections. Sewer service curb connections shall be constructed as shown on the plans, and shall be laid in accordance with the specifications for vitrified pipe sewers from the main sewer to a point three feet back of the curb line.
Wherever test "T"s are installed, the same shall be encased in Class "C" concrete to a point opposite the top of the upper sewer.
All curb connections shall be closed at the outer end with vitrified stoppers, sealed with approved bituminous jointing compound.
Where concrete encasement of curb connections is specified, or called for on the plans, the cost of such concrete encasement shall be included in the contract unit price for curb connections.
(s) Leakage Tests for Sewers. All sewers constructed under these specifications shall be tested for leakage, in the following manner:
(1) Single sewer construction. As soon as a section of sewer has been constructed between manholes, and the manholes have been completed, a suitable plug manufactured for that purpose shall be inserted in the sewer at the lower manhole, and the section filled with water to a head of at least one foot above the top of the sewer pipe in the upper manhole. The drop in head at the upper manhole shall not exceed one-half inch for eight-inch sewers to two inches for thirty-inch sewers for the last thirty minutes of a period of one hour.
(2) Dual sewer construction. In testing dual sewers for leakage, the storm sewer in the lower manhole of each section shall be plugged as above specified, and the sanitary sewer shall be plugged on the downstream side of the lower manhole and on the upstream side of the upper manhole. The storm sewer shall then be filled with water to a head of at least one foot above the top of the storm sewer pipe in the upper manhole. The increase in head at the lower sanitary manhole shall not exceed one-half inch in the thirty minute period following filling of the storm sewer.
In making the above tests, all equipment and labor shall be furnished by the owner and the cost thereof shall be included in the price per linear foot of sewer.
Any section of sewer showing leakage in excess of the amounts above specified shall be repaired or replaced at the expense of the owner.
(t) Service Markings. Wherever a stone or concrete sidewalk or curb exists, service connections shall be indicated by witness signs cut into the sidewalk or curb. Each riser, slant or "Y" connection left plugged at the sewer shall be evidenced by a triangle and each sewer curb connection plugged at the curb shall be evidenced by an arrow.
(u) Leakage Test for Water Mains. Wherever sewer work is adjacent to a water main, tests of the main shall be made at the owner's expense, upon completion of the sewer work along each section of water main between line valves to determine if any leakage has been caused by the owner's operations. In case leakage is shown by the test, the owner shall have the same repaired at his own expense.
(v) Additional Concrete. Whenever, in the opinion of the Engineer, additional concrete is required over and above that required by the plans or specified elsewhere herein, he may order the owner to install or place additional concrete and when so ordered, the same shall be placed and paid for under the item "additional concrete".
(w) Clearing Street, Cleaning Up and Repairs. The owner shall remove surplus excavated material or construction materials as the work progresses, and shall keep the street in a safe and convenient condition for travel.
Before final acceptance of the work, the owner shall, by means of a drag or by flushing, as directed by the Engineer, clear the sewers of any mortar, bituminous compound, dirt or other refuse that may have been left or accumulated in the sewers. All manholes, inlets and other structures shall be cleared of all forms, scaffolding, centering, surplus mortar, rubbish or dirt, and left in a clean and proper condition.
All surplus material, tools, equipment and temporary buildings shall be removed from the site of the work, and all street surfaces, gutters, walks, lawns, rights of way or other property shall be restored to as good a condition as originally found.
The owner, at his own expense, shall repair any and all damage he has caused to the street or adjoining property and shall save free and harmless the principal in this contract from all suits for damages to persons or property arising from or caused by this construction.
(x) Restoration of Sidewalks, Curbing and Paving. All pavements, road surfaces, sidewalks, driveways or curbs which the owner is required to replace shall, at the expiration of the period of maintenance, be replaced in the same manner as the original installation or as specified by the Engineer and the cost of such replacement shall be borne by the owner, unless otherwise specified.
(y) Final Repairs. Four months after the final measurements have been taken, the Engineer shall make an examination of all surfaces where sewers have been constructed, and shall note any depressions due to breakage, settlements, washouts or other causes that may be attributed to the construction of sewers. Upon written order from the Engineer, the owner shall again go over the work and repair breaks, refill depressions, remove any surplus that has previously been left upon the trenches, or make other repairs or replacements which are necessary to place all the work in first class condition.
(z) Special Requirements.
(1) Protection of underground and surface structures. Unless otherwise specified or shown on the plans, the owner shall, at his own expense, support, protect, maintain and, if necessary, repair or replace to the complete satisfaction of the owners thereof, all underground and surface utility structures, drains, sewers, culverts, water pipes and other such obstructions encountered in the progress of the work which cross the sewer trench or which run parallel with and outside the limits of the sewer trench as defined in subsection (c) herein. Such responsibility on the part of the owner shall be in effect whether or not such obstructions are shown on the plans.
Unless otherwise specified, all underground utility structures, drains, sewers, culverts, water pipes and other such obstructions, which run substantially parallel with the sewer trench and which are encountered within the limits of the sewer trench as defined in subsection (c) herein and which are not shown on the plans, shall be replaced or repaired by the owner at the expense of the owners thereof at prices to be agreed upon in writing by the Engineer and owner.
(2) Time. The owner shall begin the construction of sewers as soon as practicable, unless otherwise ordered by the Engineer, and in all cases he shall begin the construction within five days after receipt of written notice from the Engineer to do so. He shall prosecute the work diligently, effecting completion of the work within the time limits of this contract.
(Ord. 538-55. Passed 4-4-55.)