Section 2503.  Storm Sewers

 

2503.01     description.

This section was developed in conjunction with Section 4020 of the SUDAS Standard Specifications, with modifications to suit the needs of the Department.

 

A.    Construct storm sewers.

 

B.    Abandon storm sewer.

 

C.    Cleaning, inspecting, and testing storm sewers.

 

D.    Cleaning and inspecting pipe culverts.

 

E.    Cleaning, inspecting, and testing rehabilitated pipe.

 

F.     Low clearance pipe is defined as either arch or elliptical pipe. Unless specified otherwise, Contractor may supply either pipe shape when low clearance pipe is specified.

 

2503.02     materials.

Apply Article 4149.03..

 

2503.03     construction.

 

A.    Examination.

 

1.     Verify measurements at site. Make necessary field measurements to accurately determine pipe makeup lengths or closures.

 

2.     Examine site conditions to ensure construction operations do not pose hazards to adjacent structures or facilities.

 

B.    Pipe Installation.

 

1.     General.

a.     Clean pipe interior and joints prior to lowering into trench. Keep pipe clean during construction.

b.     Begin at the lowest point in line. Lay groove or bell end pointing upstream unless specifically noted otherwise.

c.     Place pipe with lifting holes at the top of the pipe and fill lift hole with non-shrink grout or manufactured plugs.

d.     Assemble joints as specified by the pipe manufacturer. When specified, wrap exterior of storm sewer pipe joints with engineering fabric.

e.     Use a saw to cut ends of pipe flush with inside wall manholes, intakes, and structures. Do not use hammer or other means to break pipe.

f.      Provide manholes and intakes as specified in the contract documents.

g.     Use watertight stopper, plug, or other approved means to protect the exposed upstream ends of the pipe and prevent soil sediment from entering the storm sewer system.

 

2.     Trenched.

a.     Excavate trench and provide bedding and backfill material as specified in Section 2552. If reinforced concrete elliptical pipe is used, provide pipe bedding as specified in the contract documents.

b.     Prepare trench bottom to design line and grade so that only minor movement of pipe is necessary after installation.

c.     Lay pipe to design line and grade. Set field grades to invert of pipe.

d.     Provide uniform bearing for full pipe barrel length. Excavate bell holes as necessary for uniform support of pipe barrel on bedding material.

e.     Do not lay pipe in water or on saturated soil or bedding, or allow water to rise in trench around pipe prior to placing backfill material.

f.      Do not disturb installed pipe and bedding when using movable trench boxes and shields. Block or anchor pipe as necessary to prevent joint displacement.

 

3.     Trenchless.

Apply Section 2553.

 

C.    Storm Sewer Pipe Installed within a Casing Pipe.

Apply Article 2553.03, D, for installation of storm sewer pipe within a casing pipe.

 

D.    Pipe Jointing.

 

1.     General.

a.     Clean joint surfaces to remove soil or foreign material prior to jointing pipe.

b.     Assemble joints according to the pipe manufacturer’s recommendations. Use equipment that does not apply damaging forces to pipe joints.

 

2.     Reinforced Concrete Pipe, Reinforced Concrete Arch Pipe, and Reinforced Concrete Elliptical Pipe.

a.     Wrap non-sealed joints unless otherwise specified. Comply with Standard Road Plan SW-211 for pipe joint wrapping. Wrap joints with engineering fabric meeting requirements of Article 4196.01, B, 3. Secure engineering fabric in place to prevent displacement while placing backfill material.

b.     If a rubber O-ring or profile gasket is specified for RCP, coat the rubber gasket and joint with soap based lubricant immediately prior to closing the joint.

c.     Place pipe such that joint openings on the outside or inside of the pipe do not exceed 1/2 inch.

 

3.     Reinforced Concrete Low Head Pressure Pipe, Polyvinyl Chloride Pipe and Corrugated PVC Pipe, and High Density Polyethylene Pipe.

Coat gasket and joint with soap based lubricant immediately prior to closing the joint.

 

4.     Corrugated Metal Pipe and Corrugated Metal Arch Pipe.

Lap coupling bands to form a tightly closed joint upon installation.

 

5.     Connections between Dissimilar Pipes.

a.     Use manufactured adapters or couplings approved by the Engineer.

b.     Where adapters or couplings are not available, the Engineer may authorize use of concrete collar as shown in the contract documents.

 

E.    Aprons.

 

Install pipe aprons where specified in the contract documents. Install apron guards when specified.

 

F.     Tolerances.

 

1.     Ensure horizontal and vertical alignment does not vary from design line and grade at any structure by more than 1% of the inside diameter of the pipe or 1/4 inch, whichever is larger.

 

2.     Do not allow horizontal alignment of pipe to vary from design line at any point along pipe by more than 1% of the inside diameter of the pipe.

 

3.     Low spots holding water exceeding the following depths for each pipe size will be considered unacceptable and shall be removed and reinstalled to proper grade.

 

Table 2503.03-1: Gravity Main Tolerance

Pipe Diameter

Maximum Low Spot  Depth

8”

1/2”

10”

1/2”

12”

3/4”

15”

3/4”

18” and larger

5% of Pipe Diameter*

* Measured to the nearest 1/2”

 

G.    Conflicts.

Apply Article 2554.03, A, 7.

 

H.    Storm Sewer Abandonment.

 

1.     Plug.

a.     Prior to placing the sewer plug, the Engineer will verify the sewer line is not in use.

b.     Construct sewer plug by completely filling the end of the pipe with concrete. Force concrete into the end of the pipe for a distance of 16 inches, or one-half the pipe diameter, whichever is greater.

 

2.     Fill.

a.     Prior to filling sewer, Engineer will verify sewer line is not in use.

b.     If specified in the contract documents, fill the line to be abandoned with flowable mortar or CLSM, according to Article 2552.02, G, by gravity flow or pumping.

 

I.      Connection to Existing Manhole or Intake.

Apply Article 2435.03, E.

 

J.     Cleaning, Inspection, and Testing.

Apply Articles 2504.03, L, 1; 2; 3; and 5. Video inspection of storm sewers is not required on Interstate, Primary, State Park, and Institutional Road Projects.

 

2503.04     method of measurement.

 

A.    Storm Sewer.

 

1.     Trenched.

Measurement for each type and size of pipe installed in a trench will be in linear feet along the centerline of the pipe from center of intake or manhole to center of intake or manhole. Where the end of the pipe discharges to a ditch or waterway, measurement will be to the end of the pipe, exclusive of aprons. Lengths of elbows and tees will be included in the length of pipe measured.

 

2.     Trenchless.

Measurement for each type and size of pipe installed by trenchless methods will be in linear feet along the centerline of the pipe.

 

B.    Storm Sewer with Casing Pipe.

 

1.     Trenched.

Measurement for each type and size of pipe installed with a casing pipe in a trench will be in linear feet along the centerline of the casing pipe from end of casing to end of casing.

 

2.     Trenchless.

Measurement for each type and size of pipe installed by trenchless methods with a casing pipe will be in linear feet along the centerline of the casing pipe from end of casing to end of casing.

 

C.    Removal of Storm Sewer.

Measurement for each type and size of pipe removed will be in linear feet from end to end.

 

D.   Connection to Existing Manhole or Intake.

Connections to existing manhole or intake will be measured according to Article 2435.04, G.

 

E.    Storm Sewer Abandonment.

 

1.     Plug.

Each plug installed in a pipe will be counted.

 

2.     Fill and Plug.

Measurement for each size of pipe filled and plugged will be in linear feet from end of pipe to end of pipe.

 

F.     Cleaning, Inspecting, and Testing.

None.

 

G.    Aprons.

Measured according to Article 2416.04, B and 2417.04, B.

 

2503.05     basis of payment.

 

A.    Storm Sewer.

 

1.     Trenched.

a.     Payment will be made at the contract unit price per linear foot for each type and size of pipe.

b.     Payment is full compensation for:

·         Trench excavation,

·         Dewatering,

·         Furnishing bedding material,

·         Placing bedding and backfill material,

·         Joint wrapping,

·         Wyes and other fittings,

·         Pipe joints and pipe connections, and

·         Testing and inspection.

 

2.     Trenchless.

a.     Payment will be made at the contract unit price per linear foot for each type and size of pipe.

b.     Payment is full compensation for:

·         Furnishing and installing pipe,

·         Trenchless installation materials and equipment,

·         Pit excavation, dewatering, and placing backfill material,

·         Pipe connections, and

·         Testing, and inspection.

 

B.    Storm Sewer with Casing Pipe.

 

1.     Trenched.

a.     Payment will be made at the contract unit price per linear foot for each type and size of pipe.

b.     Payment is full compensation for:

·         Furnishing and installing both carrier pipe and casing pipe,

·         Trench excavation,

·         Dewatering,

·         Furnishing bedding material,

·         Placing bedding and backfill material,

·         Furnishing and installing annular space fill material,

·         Casing spacers,

·         Pipe connections, and

·         Testing and inspection.

 

2.     Trenchless.

a.     Payment will be made at the contract unit price per linear foot for each type and size of carrier pipe.

b.     Payment is full compensation for:

·         Furnishing and installing both storm sewer pipe and casing pipe,

·         Trenchless installation materials and equipment,

·         Pit excavation, dewatering, and placing backfill material,

·         Casing spacers,

·         Furnishing and installing annular space fill material,

·         Pipe connections,

·         Testing, and inspection.

 

C.    Removal of Storm Sewer.

 

1.     Payment will be made at the contract unit price per linear foot (meter) for each type and size of pipe removed.

 

2.     Payment is full compensation for removal, disposal, and capping (if specified) of pipe.

 

D.   Connection to Existing Manhole or Intake.

Connections to existing manhole or intake will be paid according to Article 2435.05, G.

 

E.    Storm Sewer Abandonment.

 

1.    Plug.

a.     Payment will be made at the contract unit price for each plug installed.

b.    Payment is full compensation for trench excavation (if necessary), cutting pipe (if required), furnishing and placing plug materials, and placing backfill.

 

2.     Fill and Plug.

a.     Payment will be the contract unit price per linear foot for each size of pipe filled and plugged.

b.    Payment is full compensation for trench excavation (if necessary), cutting pipe (if required), furnishing and placing pipe fill material, furnishing and placing plug materials, and placing backfill.

 

F.     Cleaning, Inspecting, and Testing.

Cleaning, inspecting, and testing storm sewers and pipe culverts is incidental to other project costs and will not be paid for separately.

 

G.    Aprons.

Paid according to Article 2416.05, B and 2417.05, B.