Chapter 22C Standards for Improvements Construction

Gravity Sewers.

All pipe and fittings for gravity sewers to fifteen inch in diameter shall be polyvinyl chloride (PVC) conforming to ASTM Specifications D-3034, F-679 and ASTM D1784 for SDR-26 pipe.

Sanitary sewer 18 inches and larger in diameter shall be PVC conforming to ASTM F-689 for T-1 Wall or ASTM F-789 for PS-46.

Where required by the Pennsylvania Department of Environmental Protection (DEP) or the Township, ductile iron pipe shall be substituted for PVC pipe. Ductile iron pipe shall be manufactured in accordance with ANSI/AWWA C151/A21.51 latest revision. The metal thickness shall be Class 51.

Fittings shall be ductile iron and be manufactured in accordance with ANSI/AWWA C-110/A21.10, latest revision. All ductile iron pipe and fittings shall be cement lined in accordance with ANSI/AWWA C104/A21.4. The cement lining shall be standard thickness. Interior and exterior coating of the pipe and fittings shall be coal tar epoxy, Pennoxy-Tar 32-B-4, or approved equal, uniformly applied in a two coat application for a total minimum dry film thickness of 10 mils and shall be in accordance with AWWA C151, latest revision.

All pipe delivered to the site shall be accompanied by a letter from the manufacturer certifying that the pipe furnished complies with the ASTM requirements for the type and class of pipe specified.

PVC pipe and fitting joints are to be of rubber, marked to indicate nominal pipe size and proper insertion direction according to the specific manufacturer's requirements. Ductile iron pipe joints shall be push-on type conforming to AWWA Specifications C111, latest revision. Gaskets shall be natural rubber compression type conforming to ASTM Specifications C-564, latest revision.

Low Pressure Sewer Systems.

Sanitary sewer low pressure force main pipe and fittings shall meet the requirements of ASTM Specifications D1784 and AWWA Standard C900. Class 150 pipe shall conform to the requirements of SDR 21. All pipe shall be polyvinyl chloride (PVC). Elastomeric-gasket bell ends shall be used and shall consist of an integral wall thickened section. Each length of pipe and fitting shall be marked with the following information: Manufacturer; Size; Material Code Designation; SDR; AWWA pressure class; and AWWA Designation Number.

The pipe joints for the required tees, bends, fittings and pipe sections for the PVC sanitary sewer laterals shall meet the requirements of ASTM Specification D1784 and AWWA Standard C900. Class 150 pipe shall conform to the requirements of SDR 21. The minimum permitted size of Tee fittings shall be two inches by 1 1/4 inches. Tee fittings shall be installed with the necessary materials including bushings or adapters where required, to complete the required lateral installations shown on the construction drawings and details. Each tee and lateral pipe joint shall have an elastomeric-gasket bell end and shall consist of an integral wall thickened section. Requirements for the qualifications for potable-water service do not apply. The tee fitting connections shall be compatible with the required low pressure sewer mainline pipe. Each fitting shall be marked or identified by a written manufacturer's certification with the following information: Manufacturer; Size; Material Code Designation; SDR; AWWA pressure class; and AWWA Designation Number.

Where required by DEP or the Township, ductile iron pipe shall be substituted for the PVC pipe as specified on the drawings. Interior and exterior coating of pipe and fittings shall be coal tar epoxy, Pennoxy-Tar 32-B-4 or approved equal, uniformly applied in a two coat application for a total minimum dry film thickness of 14 mils and shall be in accordance with AWWA Specifications C151, latest revision.

All pipe delivered to the site shall be accompanied by a letter form the manufacturer certifying that the pipe furnished complies with the ASTM requirements for the type and class of pipe specified.

Manholes and manhole frames and covers shall be in accordance with Subsection 1B and C of these specifications with the exception that manholes less than five feet deep shall have a pre-cast reinforced concrete flat top section with an H-20 design load.

Curb boxes and risers shall be cast iron with screw-type shaft and locking lid with a pentagonal brass plug. Riser shaft shall be sufficiently long trough to extend from the shut-off valve to final grade, and still retain a minimum of four-inch height adjustment. Curb box cover is to be identified as "sewer" in casting. Curb box and riser shall be equal to Tyler Pipe 6850 series adjustable cast iron curb boxes with enlarged base and foot piece.

(g)

Shut-off valves located at intermediate and terminal manholes shall be Hayward True Union Ball Valves or equivalent. The shut-off valves shall be of PVC construction, shall have no flow restriction and provide V4 turn on/off control. Control operation shall be by attached handle.

(h)

Shut-off valves located on the 1 1/4-inch service laterals shall be Hayward True Union Ball Valves or equivalent. The shut-off valves shall be of PVC construction, shall have no flow restriction, and provide one-quarter turn on/off control. A pipe stub one foot long with water tight cap shall be installed at the shut-off valve. This cap shall be removed to complete the house connection.

(i)

The sewage air release valve shall have a cast iron body and cover with a concave float designed to operate under pressure to allow entrapped air and gases to escape from a sewage force main, sewage pump, or low pressure sanitary sewer system. After the air and gases escape from the air release valve, the valve shall shut-off automatically until more air or gases accumulate in it and the opening cycle repeats automatically. The air release valve shall shut-off without spilling sewage and shall be spurt free.

(j)

The sewage air release valve shall have a compound internal linkage mechanism, all stainless steel, to prevent corrosion. The float stem shall be approximately 15 inches long to provide an air gap between the linkage and waste level inside the valve to prevent the waste from clogging the linkage. The float shall be heavily constructed stainless steel; hermetically sealed; and have a concave bottom impact area to provide immediate resistance to flow and instant upwards movement to shut-off the large orifice without spilling or spurting. All valves shall be complete with a quick disconnect hose assembly, blow-off valves and attachments to permit back-flushing without dismantling valve.

(k)

The air release valve shall be an APCO Model 400SARV Sewage Air Release Valve with attachments and two inches, three inches or four inches N.P.T. inlet (as specified), as manufactured by Valve & Primer Corporation, Schaumburg, Illinois, U.S.A., or approved equal.

Manholes.

Sanitary sewer manholes shall be precast reinforced concrete conforming to ASTM C-478 and AASHTO M-199, latest revision. All precast reinforced concrete base sections shall be manufactured with a minimum 12 inches horizontal clearance between the top of the pipe opening and top of the precast interior section joint. Where pipe connections are required, manholes shall contain approved flexible manhole pipe sleeves cast into the manhole sections. All precast sections shall be coated on the exterior surfaces with a minimum thickness of 14 mils of Hydrocide 648, or an approved equal. Generally, a two to three inch leveling course of 2A material will be required beneath the manhole base. Manholes shall meet the requirements of PennDOT Publication 408, § 714 and PennDOT Standard RC-39. Manhole section joints shall be O-ring rubber gaskets or sealed with two rows of an approved nonhardening mastic. If O-ring joints are used the interior of the joint shall be mortared.

Pipe entering manholes shall extend into the manhole two inches and be grouted in place.

Manhole channels and benches shall be poured concrete to a depth of 0.80 of the pipe diameter and shall be sloped to the channel. Concrete shall be PennDOT Class "A" twenty-eight-day compressive strength 3,300 PSI. Precast channels must be approved by the Township Engineer prior to use.

Ladder rungs shall have non-skid surface meeting the requirements of PennDOT Specification 408, § 605.2(c) and PennDOT Standard RC-39. Aluminum alloy ASTM-B-221, 6061-T6, 6005-T5, or 6351-T6, with a protective coating applied to the portion to be embedded in the concrete.

Drop manholes shall include a threaded anchor bolt (3/4 inch minimum). The concrete drop encasement shall be anchored to the manhole wall by means of a threaded bolt through the manhole wall. The anchor bolt shall extend a minimum of six inches into the concrete encasement and shall bear against a minimum four-inch square 1/4-inch thick steel plate on the interior side of the manhole. The surfaces of the anchor bolt inside the manhole shall be coated with bitumastic. Alternate methods of construction must be reviewed and approved by the Township Engineer prior to use.

Manhole Frames and Covers.

Standard manhole castings shall be heavy duty with ANSI H-20 loading, having a clear opening of 21 inches, with a lid diameter of 22 3/4 inches. The casting shall be equal to Campbell Foundry Corp. No. 1004A. Watertight manhole frames and castings shall be equal to Campbell Foundry Corp. No. 21538 and shall have a lid diameter of 25 1/2 inches.

All manhole castings, standard and watertight, shall be provided with self-sealing manhole lids including nonpenetrating pickholes and a flexible gasket installed in a machine groove in the frame or lid bearing surface of the manhole. The letters "LMT" and the word "SANITARY" in two-inch letters shall be cast into the manhole cover.

All castings shall be true to form and dimensions and shall be free from inclusions of foreign material, casting faults, injurious blow holes, cracks, sponginess, and other defects rendering them unsuitable. The finished frame and cover or grate shall have the bearing surfaces machined or ground so that there will be no variations that will permit rocking or rattling, and the diameter of the cover or grate shall be such as to fit and frame without wedging. All castings shall be thoroughly cleaned and given one coat of Hydrocide 648 or equal at the factory.

Manhole castings shall be placed on a minimum of three courses of twenty-four-inch I.D. precast, reinforced concrete adjusting rings, to a maximum height of 18 inches from the top of the manhole section to the finished grade of the casting. Frame and grade rings shall be attached to the top of manholes using three 1/2-inch diameter threaded studs with hex nut and washer.

Underground Marking Tape.

Underground marking tape shall be a minimum of six inches wide, .35 mil thick, with a solid foil core encased in a protective plastic jacket that is resistant to alkalis, acids and other destructive substances commonly found in soils. The underground marking tape shall be detectable by an inductive method type of locator.

The underground marking tape shall meet ASTM D-1712 (modified for 48 hours) for color stability. The color shall be in accordance with the requirements of Act 38-1991 (i.e., Safety Green for sanitary sewer, Safety Red for electric, Safety Orange for telephone). The underground marking tape shall have a warning message (i.e., Caution Sewer Line Buried Below; Caution Electric Line Buried Below; Caution Telephone Line Buried Below) imprinted on one side, repeated for the entire length of the tape in permanent ink that cannot be removed by handling or underground burial.

The underground marking tape shall be Terra Tape Sentry Line 620, as manufactured by Reef Industries, Inc., or approved equal.

Excavation.

When rock or noncushioning material is encountered in trench excavation, a cushion at least eight inches thick shall be placed between the rock and the bottom of the pipe. The cushion shall consist of clean sand or equivalent granular material. The bottom of the trench shall be excavated to a horizontal section as far as practicable.

Blasting shall be done only after obtaining necessary permits from state and local agencies, as applicable.

Should unstable soil be encountered or should the Engineer deem it necessary to excavate to a depth below the grade shown on the plans to secure a good foundation, the contractor shall remove the unstable soil for the full width of the trench and replace it with AASHTO #3 stone or larger, as approved by the Engineer. The pipe bedding shall be constructed on top of the #3 stone. The Engineer shall determine the depth of removal of unstable soil and the amount of backfill necessary. The backfill shall be thoroughly compacted and shaped to form the bed for the pipe.

Common excavation shall not be carried below the required depth. When this is done, the trench shall be backfilled with material approved by the Engineer and compacted to the density of the surrounding earth material, as determined in accordance with the AASHTO Designation T99, Method C.

Where the bottom of the trench is found to be an inadequate foundation for the pipe and cannot be stabilized by the above methods, a concrete pad or cradle of sufficient size shall be constructed as approved by the Engineer.

The minimum width of the trench at the top of the pipe when placed shall be at least equal to the outside diameter of the pipe plus eight inches on each side of the pipe. The trench shall be excavated accurately to the established line so that at least an eight-inch space will exist between the side of the trench and the side of the pipe. The maximum allowable width of trench shall not exceed 16 inches on each side of the pipe when placed.

(7)

The side of the trenches shall be vertical. Where sloping of trench walls is necessary, sides of trenches shall be vertical for a minimum distance of four feet above the top of pipe.

Construction.

Lines and Grades.

The lines and grades of all sewers and pipe lines to be constructed shall be established by means of offset stakes, pins or other survey marks. Grades shall be furnished at intervals of 50 feet for grades of 0.80% and over, and at intervals of 25 feet for grades under 0.80%.

When the contractor uses a laser to establish line and grade for laying the pipe, periodic checks shall be made by the contractor from grade stakes furnished at intervals not greater than 100 feet.

Dewatering. Any water which collects in an excavation shall be removed by the contractor before proceeding with the construction of the pipe line or structures.

Pipe Installation.

All pipe shall be laid to true alignment and grade and progress upstream with hubs upgrade and ends fully and closely jointed. Pipe shall be supported for the full length of the barrel and the bell holes shall be excavated to prevent bearing on the joints.

All pipe shall be installed in accordance with recommended practices of the manufacturer.

Cutting of pipe for closure pieces or other reasons shall be done in a neat and workmanlike manner by a method conforming with the manufacturers recommendations. Excess pipe from closures cannot be used to begin a sewer line run unless the piece of pipe is 10 feet long, measured from the outside wall of the manhole to the first joint.

All gravity sanitary sewers shall be installed with a minimum of five feet of cover. Sanitary sewer force mains require a minimum of four feet of cover.

All PVC and ductile iron pipe shall be laid in a special envelope of material conforming to PennDOT Specifications for 2A Crushed Stone. The pipe envelope shall be a minimum compacted thickness of four inches below the bottom of the outside barrel extending the full width of the flat, compacted trench bottom and extending vertically at full trench width to a minimum height of 12 inches above the top of the outside barrel of the pipe.

The trench bottom width shall be reduced to the width necessary to provide a free working space on each side of the pipe but shall in no event exceed the outside diameter of the barrel of the pipe plus 16 inches for a minimum height of four foot above the top of the pipe.

(g)

Until placed in use, the ends of all service laterals and wye or tee-wye branches installed for future use shall be stopped with plugs fitted with the same joint as the sewer pipe and located with a two-inch by four-inch wooden marker extending vertically from the pipe invert to a minimum of two inches above the finished grade.

(h)

When two service laterals are installed such that they are serving adjacent lots on the same side of the sewer main, said service laterals shall be installed with a three foot minimum horizontal clearance between them. All service laterals shall be installed such that a five foot minimum horizontal clearance is maintained from the outside of manhole walls and other structures.

(i)

All sanitary sewer laterals shall be a minimum of six-inch diameter pipe within dedicated sanitary sewer easements or public right-of-ways. Sewer laterals shall be laid at a minimum slope of 1/4-inch per foot and perpendicular to the main sewer line.

(j)

All sanitary sewer laterals shall include a cleanout which shall be constructed in accordance with the design graphic entitled "LMT Sanitary Sewerage System Sewer Cleanout Detail," a copy of which is attached hereto and is incorporated by reference, and at the following locations: (See Exhibit 22C-1)

If the sewer lateral extends into a street right of way which is bounded by a curb, the clean out shall be located one foot on the residence side of the curb.

If the sewer lateral extends into a street right of way which is not bounded by a curb, the clean out shall be located one foot within the boundary of the right of way of the street.

Specials. The contractor shall lay six-inch wye or tee-wye branches for the purpose of making service lateral connections at each lot shown on the plans and elsewhere if so directed by the Engineer. The branches shall be laid at an angle with the horizontal compatible with a lateral slope of 1/4-inch per foot, and have their ends plugged with an approved stopper. The contractor is cautioned that the sewer is to be tested by a leakable test as described elsewhere in these specifications and that the method used to secure the plugs in the branches and laterals must be such that the plugs will withstand the internal pressure of the test.

Manhole Installation.

All precast concrete bases shall be placed on a bedding or leveling course consisting of two to three inches of PennDOT No. 2A Coarse Aggregate.

The manhole joint sections shall be sealed with two continuous rings of joint sealant material. Excess sealant material which has pushed through the inside joints shall be neatly trimmed off.

Manhole steps shall be located over the bench area in the manhole base.

The invert shall be formed with PennDOT Class A cement concrete. The invert shall be troweled to a smooth finish. Benches shall be sloped toward the invert at 1/4-inch per foot and shall have a brushed, nonslip finish. Precast channels must be approved by the Engineer prior to use.

Final grade adjustment of the manhole casting shall be a maximum 12 inches and done with precast concrete riser rings. The concrete riser rings and castings shall be set on a three-inch wide by 1/4-inch thick strip of joint sealant material with the inside and outside of the rings to be neatly mortared.

Drop Connections. Vertical drop connections shall be constructed of the same size, material and class of pipe and fittings as used for the main line construction. The drop connection shall be encased in a minimum of six inches of PennDOT Class "A" cement concrete in accordance with the standard details. Precast concrete drop connection blocks must be approved by the Engineer prior to use in the field.

Backfill. All trenches and excavations shall be backfilled within a reasonable time after the pipe and appurtenances are installed. The method of backfilling shall be as follows:

Within State Highway Right-of-Way. Backfilling shall be done in accordance with the requirements of the state highway occupancy permit. Backfill requirements begin at the top of the pipe envelope and continue to the existing or proposed subgrade.

Within Township Roads. When excavation of an existing Township Road is required, it shall be done in accordance with requirements of the Township Road opening permit. The backfill shall be as follows:

Prior to excavation, all trenches in the existing road are to be saw-cut the full depth of the bituminous paving.

Backfill with PennDOT 2A or 2RC crushed stone compacted in eight-inch layers to finished grade and meeting the compaction requirements of Subsection 1G(2)(d).

Top existing trench with two inches of compacted bituminous stockpile patching material (cold patch).

After 90 days of settlement time, the cold patch and backfill material shall be removed and the trench shall be saw-cut an additional one-foot beyond the initial cut and paved in accordance with Township specifications.

All Other Areas.

Backfill for the remainder of the trenches or excavations shall be approved material and free from organic matter, large or frozen lumps, or stones over 10 inches in their largest dimensions. Stones which are used in backfilling shall be so distributed through the mass that all interstices are filled with fine material.

The material shall be moistened or dried, if necessary, to obtain the required compaction. Backfill material shall be approved by the Engineer. Special care shall be taken in placing the backfill. Particular care shall be used to obtain thorough compaction under the haunches and along the sides of the top of the pipe.

All backfill shall be placed in loose layers not exceeding six inches in depth under and around the pipe and not exceeding eight inches over the pipe. Successive layers shall be added and thoroughly compacted by hand and pneumatic tampers until the trench is completely filled to the elevation as directed. Compaction shall be in accordance with the requirements of Subsection 1G(4). Backfilling shall be done in such a manner as to avoid injurious top or side pressures on the pipe.

Compaction Requirements.

Backfill shall be compacted to a density satisfactory to the Engineer. A thoroughly and satisfactorily compacted backfill is defined as having a minimum dry density of 95% of the maximum density. The maximum density is the maximum dry weight density in pounds per cubic foot as determined by the AASHTO Standard Density Test, T 99, Method C. Where the backfill material consists of sand or silt containing less than 20% by weight of particles passing the No. 200 mesh sieve, a minimum dry density of 100% of maximum density will be required.

All trenches backfilled with earth shall be allowed to settle for at least 180 days before the permanent base course or pavement may be constructed unless the following procedure is used:

Utility Trench Backfill Requirements.

All utility trenches shall be backfilled with select material and shall be properly compacted with approved mechanical tampers to a minimum compaction of 97%. Compaction testing is required and shall be performed as determined by the Township Engineer. All unsuitable or unstable material shall be replaced with suitable backfill material.

Subbase and base course shall not be placed until 30 days prior to the issuance of the first certification of occupancy and shall be placed on only those specific roadways required for the occupancy of the unit.

Prior to construction of the bituminous concrete wearing course, all trench settlement areas shall be excavated to the depth of the unconsolidated or unacceptable backfill material, as determined by the Township Engineer. The excavated areas shall be backfilled with crushed stone material compacted in maximum lifts of six inches to a minimum compaction of 97%, after which the base course shall be replaced.

The bituminous concrete wearing course shall not be constructed until at least two years after the base course is completed.

The maintenance period for the roadway shall be extended to three years.

Placement of subbase and bituminous concrete base course for proposed roads within Township right-of-way where the trenches were backfilled with crushed stone can proceed following completion of backfill.

Gravity Sewer Pipe Testing.

All sewers must be laid true to line and grade between manholes and must pass a visual test of straightness. If infiltration in any test section exceeds 50 gallons per inch diameter of pipe per mile of length in 24 hours, or if exfiltration exceeds 50 gallons per inch diameter of pipe per mile of length in 24 hours, the system will not be accepted or certified for use until corrections are made. No infiltration or exfiltration will be permitted within 200 feet of a water supply source. All infiltration and exfiltration tests in sanitary sewer lines and manholes must be performed by the developer and observed by the Township Engineer.

If the pipe to be tested is submerged in ground water, the contractor shall use low pressure air testing facilities to determine the acceptability of the test section. Air testing shall be performed in the following manner:

If the pipe to be tested is submerged in ground water, insert a pipe probe by boring or jetting into the backfill material adjacent to the center of the pipe and determine the pressure in the probe when air passes slowly through it. (This is the back pressure due to the probe). All gauge pressures in the test should be increased by this amount.

Plug all pipe outlets with suitable test plugs. Brace each plug securely.

Add air slowly to the portion of the pipe installation under test until the internal air pressure is raised to 4.0 psig.

After an internal pressure of 4.0 psig is obtained allow at least two minutes for air temperature to stabilize, adding only the amount of air required to maintain that pressure.

When pressure decreases to 3.5 psig, start stopwatch. Determine the time in seconds that is required for the internal air pressure to reach 2.5 psig.

Minimum permissible pressure holding times for runs of single pipe diameter of eight inches, 10 inches, 12 inches and 15 inches and for systems in combination with trunk lines are indicated in the following tables. These tables indicate minimum holding time in seconds required for pressure to drop from 3.5 psig to 2.5 psig.

Manhole Testing.

All manholes shall be vacuum tested. The approved testing equipment shall be installed and test performed above the joint between the manhole frame and leveling courses.

Vacuum Testing. Ten inches of mercury vacuum shall be drawn and the vacuum pump shut off. The test requires a loss of no more than one inch of mercury within 60 seconds for a forty-eight-inch diameter manhole, 75 seconds for a sixty-inch diameter manhole and 90 seconds for a seventy-two-inch diameter manhole.

Mandrel Testing.

Mandrel testing is required for all PVC gravity mainline sewers. The testing equipment (rigid ball or mandrel approved by Engineer) shall have a diameter equal to 95% of the inside diameter of the pipe and shall be performed without mechanical pulling devices, with no pipe exceeding a deflection of 5%.

Mandrel tests shall be conducted not less than 30 days after final backfill has been placed.

Low Pressure Sewer Testing.

After the pipe laying is entirely completed, the joints in all pipe lines and appurtenances shall be capable of withstanding a static pressure (psi) of two times the operating pressure of the system for a minimum duration of 30 minutes. Tests of sections as they are completed are to be made by static water pressure in the presence of the Engineer.

Extreme care shall be exercised during the testing to limit the possibility of property damage due to pipe failure. Temporary thrust blocks installed for testing purposes must be adequate for the required test pressure.

Each section of pipeline shall be filled slowly with water, preferably 24 hours in advance of the time set for the test. Great care must be exercised to insure that all air is expelled from the section of line being tested prior to the test.

Should the pipe line or appurtenances show any loss of water during the tests, within said pressure, the contractor shall immediately locate and repair the leak or leaks, at his own expense.

Highway/Railroad Borings.

As required by the Pennsylvania Department of Transportation (PennDOT) and the railroad company having regulatory jurisdiction within their respective rights-of-way, borings may be permitted.

The sanitary sewer carrier pipe for said borings shall be centered within the steel casing pipe by use of steel casing insulators and end seals as manufactured by Pipeline Seal and Insulator, Inc. (PSI), or approved equal.

The steel casing insulator shall be a PVC coated steel bank with a ribbed inner liner surface that prevents slippage and protects the carrier pipe. This inner liner shall be non-conductive, and the steel bank shall have a corrosion resistant finish.

The steel casing insulator shall have six runners welded to the steel bank in accordance with AWS specifications. The runners shall be installed in a configuration of two on top and four on bottom, equally spaced.

Following installation, the steel casing insulator shall not be subject to maximum loadings greater than 30 lbs./sq. in. Sand or pea gravel, as approved by the Engineer, shall be placed to completely fill the void between the carrier and casing pipes.

§ 22C-107 Water Supply and Distribution Systems.

Steel casing insulators shall be installed within one foot of each side of all carrier pipe joints, within one foot of both ends of the casing pipe, and a maximum of 10 feet apart, or as dictated by the maximum load ratings of the steel casing insulators as approved by the manufacturer.

(7)

End seals manufactured of a highly flexible, synthetic rubber with special sealing ribs on the inside and band locating ribs on the outside may, upon approval by the Engineer, be substituted for cement grout or mortared brick. Engineer approved stainless steel bands and clamps shall be used to secure the end seal.

[Ord. 2002-1, 1/3/2002]

Specifications. Materials, workmanship and acceptance criteria shall be in accordance with the latest revision of the "General Specifications for the Water System Construction" of the Lehigh County Authority.

Backfill. Trench backfill shall be done in accordance with the requirements of § 22C-106, Subsection 1G.

§ 22C-108 Storm Drainage Systems.

[Ord. 2002-1, 1/3/2002]

Storm drainage systems shall be installed in accordance with the design standards and requirements set forth in § 22A-708 of Chapter 22A.

Materials.

Storm Sewer Pipe.

Storm sewer piping systems shall conform to the material and minimum diameter requirements specified below based upon the specific conveyance, infiltration, and/or building (roof leader) hydraulic requirements of the system:

[Amended by Ord. 2016-05, 3/17/2016]

All stormwater conveyance piping which is either within a Township right-of-way or is intended to be dedicated to the Township shall be reinforced concrete pipe (RCP) with a minimum diameter of 18 inches, of design compliant to fill depth, and complying with the requirements of the latest edition of PennDOT Publication 408.

All other stormwater conveyance piping shall have a minimum diameter of 15 inches and either be:

RCP complying with the requirements of § 22C-108, Subsection 1A(1)(a)1) above; or

Smooth-bore high-density polyethylene pipe (HDPE) complying with the requirements of the latest edition of PennDOT Publication 408.

All stormwater distribution piping within infiltration beds shall have a minimum diameter of six inches and shall be perforated corrugated HDPE pipe (or approved equal).

All piping designated for stormwater capture from roof leaders (downspouts) shall have a minimum equivalent diameter of eight inches (for nonresidential use) and either be:

Schedule 80 PVC if installed under a drive aisle or parking area; or

Schedule 40 PVC if installed under yard area which is not to be traversed with motor vehicles.

If a child-safe grate is required per § 22C-108, Subsection 1A(1)(g), (h) or (i), endwalls, headwalls and end sections must be constructed from reinforced concrete material. If HDPE pipe is proposed, it shall be inserted fully and securely into the headwall, endwall or end section opening and grouted with nonshrink grout.

Joints. Joints shall be per pipe material as specified below:

[Amended by Ord. 2016-05, 3/17/2016]

Reinforced concrete pipe (RCP) joints shall be full mortar inside and outside. O-ring gasket joints are acceptable.

High-density polyethylene pipe (HDPE) joints shall be continuous elastomeric ring gasket.

Manholes.

Manholes shall conform to ASTM C-478, PennDOT Publication 408 Specifications, §§ 605, 606 and 714 and PennDOT Construction Standards RC-39.

Steps. Provide manhole steps at twelve inch centers meeting the requirements of Publication 408 Specifications, § 605.2(c) for aluminum alloy steps.

Frame and Covers.

Provide manhole frames and covers meeting the requirements of ASTM A-48 and PennDOT Publication 408 Specifications, § 605.2(b) and PennDOT Construction Standards RC-39. Design frame and cover and grade adjustment rings for H-20 live load. Adjust to grade with concrete grade rings and cement mortar.

Manhole casting shall have a clear opening of twenty-one-inch diameter and a manhole lid diameter of 22 3/4 inches. The words "STORM SEWER" and "LMT" in two-inch letters shall be cast in the manhole lid.

Frame and precast concrete grade rings to be attached to the top of the manhole using three 1/2 inch diameter threaded studs with hex nuts and washers, inserted through frame and rings. Holes to be spaced at 120° and two inches from outside edge of frame. Embed studs four inches into manhole.

Inlets.

Inlets shall be precast concrete or poured in place construction. Construction shall be in accordance with PennDOT Publication 408 Specifications, §§ 605, 606, 714 and PennDOT Construction Standards RC-39.

For inlets that exceed five feet in height provide steps as specified in manholes.

Inlet Frame and Grates.

Tops. PennDOT Publication 408 and RC-34, Type C, Type M and Type S, as directed.

Frames. PennDOT Publication 408 and RC-34, ductile iron, or structural steel frames, as directed.

Grates. PennDOT Publication 408 and RC-34, structural steel, bicycle safe, as directed.

(g)

Concrete Endwalls/Headwalls.[1]

[Amended by Ord. 2016-05, 3/17/2016]

All upstream headwalls shall be fitted with an angled child-safety grate. Grate construction shall consist of No. 4 rebar minimum (or equivalent size material) on five-inch center-to-center grid spacing and shall fully enclose the pipe opening. The front of the grate shall be constructed at 45° from horizontal, the sides shall be vertical, and the bottom shall extend horizontally from the headwall flush with the pipe invert. All sections of the grate shall be permanently affixed to a frame which shall be constructed of one-and-one-half-inch-by-three-eighths-inch flat bar. The top of the frame shall be affixed to the headwall using bar hinges. The bottom corners of the frame shall be bolted to the headwall. Footholds shall be incorporated above the grate to within two feet of finished grade vertically above the grate.

All downstream endwalls for pipes of 30 inches in diameter or greater, or equivalent, shall be fitted with a vertical child-safety grate. Grate construction shall consist of No. 4 rebar minimum (or equivalent size material) on five-inch center-to-center vertical spacing and shall fully cover the pipe opening. All sections of the grate shall be permanently affixed to a frame which shall be constructed of one-and-one-half-inch-by-three-eighths-inch flat bar. The top of the frame shall be affixed to the endwall using bar hinges. The bottom corners of the frame shall be bolted to the headwall.

All materials shall be concrete or galvanized, as applicable.

[1]

Editor’s Note: The Endwall/Headwall Diagram is included as an attachment to this chapter.

(h)

Concrete End Sections.[2]

[Amended by Ord. 2016-05, 3/17/2016]

All upstream end sections shall be fitted with an angled child-safety grate. Grate construction shall consist of No. 4 rebar minimum (or equivalent size material) on five-inch center-to-center vertical spacing and shall fully enclose the pipe opening. The front of the grate shall be constructed at 45° from horizontal, the sides shall be vertical, and the bottom shall extend horizontally from the end section and flush with the pipe invert. All sections of the grate shall be permanently affixed to a frame which shall be constructed of one-and-one-half-inch-by three-eighths-inch flat bar. The top of the frame shall be affixed to the end section using bar hinges. The bottom corners of the frame shall be bolted to the end section. Footholds shall be incorporated above the grate to within two feet of finished grade vertically above the grate.

All downstream end sections for pipes of 30 inches in diameter or greater, or equivalent, shall be fitted with a vertical child-safety grate. Grate construction shall consist of No. 4 rebar minimum (or equivalent size material) on five-inch center-to-center vertical spacing and shall fully enclose the pipe opening. All sections of the grate shall be permanently affixed to a frame which shall be constructed of one-and-one-half-inch-by three-eighths-inch flat bar. The top of the frame shall be affixed to the end section using bar hinges. The bottom corners of the frame shall be bolted to the headwall. Footholds shall be incorporated above the grate to within two feet of finished grade vertically above the grate.

All materials shall be concrete or galvanized, as applicable.

[2]

Editor’s Note: The End Section Diagrams are included as attachments to this chapter.

(i)

Box Culverts. All box culverts that are open to the air on both sides, are 60 feet in length or less, and possess an effective open area of 20 square feet or more are exempt from the child-safety grate provisions of § 22C-108, Subsection 1A(1)(g) and (h).

[Added by Ord. 2016-05, 3/17/2016]

Construction.

Installation of Pipe. All pipe laying shall carefully progress uphill with hubs upgrade and ends fully and closely jointed. Trench widths shall not exceed the outside diameter of the pipe plus 16 inches, eight inches on either side of the pipe. Trench depths shall be as required. Trench wall shall be vertical to one foot above the top of pipe and trench bottom shall be horizontal.

Lines and Grades.

The lines and grades for storm sewer pipe to be constructed shall be established by means of offset stakes, pins or other marks. Grades shall be furnished at intervals of 50 feet for grades of 0.80% and over and at 25 feet for grades under 0.80%.

When the construction of the storm sewer pipe line and grade is controlled by the use of a laser, periodic checks shall be made by the contractor from grade stakes furnished at intervals not greater than 100 feet.

Dewatering. Any water which collects in an excavation shall be removed before proceeding with the pipe line or structure.

Rock Excavation. In rock, the contractor shall excavate the trench to the required grade plus an additional eight inches below grade prior to installation of the pipe. The extra excavation shall be filled and compacted to grade with bedding material. Blasting shall only be done by a licensed blaster only after obtaining the necessary permits required by the state or local agencies, as applicable.

Unsuitable Soil. Should unsuitable soil be encountered, the Engineer may deem it necessary to excavate and remove the unsuitable material. The unsuitable material shall be replaced with AASHTO #3 stone to the bottom of the pipe bedding.

Pipe and Structure Bedding.

Prior to laying the pipe in the trench, a bedding of PennDOT #2A stone shall be placed the full width of the trench bottom. The material shall be a minimum of four inches in depth and thoroughly compacted, with approved mechanical tampers. The bedding material shall be extended to a minimum of 12 inches above the top of the pipe and shall be compacted in eight-inch lifts with approved mechanical tampers. The bedding shall be graded to provide a uniform and continuous bearing support for the pipe and the sidewall of the trench throughout the entire length. Bell holes shall be provided at the ends of each pipe length.

§ 22C-109 Tree Planting and Landscaping.

Bedding for structures (manholes/inlets) shall be PennDOT #2A stone, two to three inches in depth, placed on a solid trench bottom or on undisturbed earth.

Backfilling. Trench backfill shall be done in accordance with the requirements of § 22C-106, Subsection 1G.

[Ord. 2002-1, 1/3/2002]

Landscape Plan. A landscape plan shall be required for all subdivision and land developments which locates and provides specifications for all trees, shrubs or other features planned by the developer.

Plant Materials. Street trees, conifers and shrubs shall be of nursery stock quality, grown under the same climatic conditions as at the development site. All materials shall be of the size indicated on the plans and required by Chapter 22A. They shall be of hearty and symmetrical growth, free of insect pests and disease.

Planting. All planting shall be at the location and spacing indicated on the plans and required by the Township Zoning Ordinance [Chapter 27] and/or Chapter 22A and shall be done in conformance with good nursery and landscape practice.

Ground Cover and Seeding.

Detention Basins. Detention basin subgrade shall be sealed with a top course of impermeable clay over the entire pond bottom and returning a minimum of one foot up the pond banks. A minimum of six inches of topsoil shall then be placed and fine graded to the design grades. Seed on the pond bottom shall be PennDOT Formula "D" placed at 21 ponds per square yard with PennDOT Formula "C" at nine pounds per square yard on the side slopes and berm. Fertilization and mulching shall be in accordance with PennDOT Form 408 Specifications.

Planting Strips and Recreation Areas. A minimum of eight inches of topsoil shall be placed and fine graded to the design grades. PennDOT Formula "B" seed mix at 21 pounds per square yard shall be placed. Fertilization and mulching shall be in accordance with PennDOT Form 408 Specifications.

Landscaping Maintenance.

[Added by Ord. No. 2020-05, 10/1/2020]

The applicant shall make arrangements acceptable to the Township that all landscape improvements installed in accordance with Township ordinances shall be guaranteed and maintained in a healthy and/or sound condition, or replaced by improvements deemed equivalent by the Township.

Landscape improvements approved for commercial, institutional, and commonly owned land at residential subdivisions and land developments shall be perpetually maintained in a healthy and/or sound condition. Applicants shall record a covenant on the property in a form acceptable to the Township Solicitor to guarantee this requirement.