(SIZE) MANHOLES CATCH BASINS AND DITCH INLETS -Item No. ADJUSTING AND REBUILDING MANHOLES, CATCH BASINS AND DITCH INLETS - Item No.

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1 (SIZE) MANHOLES CATCH BASINS AND DITCH INLETS -Item No. ADJUSTING AND REBUILDING MANHOLES, CATCH BASINS AND DITCH INLETS - Item No. Special Provision No. 407S06 July 2010 Aggregate Requirements, Lift Rings, Adjustment Units and Resilient Connectors DEFINITIONS Section of MTC Form 407, March 1984, is amended by the addition of the following: Adjustment Units: refers to circular and rectangular precast concrete units and circular and rectangular prefabricated rubber or recycled rubber units used between the structure and the frame to adjust the elevation of the frame for grates and covers. Lift Rings: refers to circular and rectangular prefabricated metal or high density polyethylene units used to adjust the elevation of the grates and covers only. They are inserted between the frame and the grates or covers MATERIALS Precast Reinforced Concrete Manholes, Catch Basins, and Ditch Inlet Components for Both Precast Concrete Units, and Corrugated Steel Pipe Units Subsection of MTC Form 407 is deleted and replaced by the following: Precast units shall conform to the requirements of OPSS 1351 amended as follows: REFERENCES Section of OPSS 1351, is amended by the addition of the following under American Society for Testing and Materials: ASTM C Standard Specification for Resilient Connectors Between Precast Reinforced Concrete Manhole Structures, Pipes and Laterals MATERIALS Section of OPSS 1351 is amended by the addition of this subsection: Resilient Connectors Resilient connectors shall conform to the requirements of ASTM C 923 M Adjustment Units Subsection of MTC Form 407 is deleted and replaced with the following: July 2010 Pg. 1 of 5 SSP407S06

2 Precast Concrete Adjustment Units Precast concrete circular and rectangular adjustment units shall conform to the requirements of OPSS 1351 as amended in this Special Provision Prefabricated Recycled Rubber Adjustment Units Prefabricated recycled rubber circular and rectangular adjustment units shall conform to the following requirements: Durometer Hardness maximum 15 Shore A variance Tensile Strength 1 MPa minimum Compression Deformation 6% +/- 2% Compression Set 4% maximum Frames, Grates, Covers and Lift Rings Subsection of MTC Form 407 is deleted and replaced by the following: Metal frames, grates, covers and lift rings shall conform to the requirements of OPSS Plastic lift rings shall be made of high density polyethylene and conform to the loading requirements of OPSS Installation of Inlet or Outlet Pipe Concrete, Clay or Plastic Pipe Clause of MTC Form 407 is amended by the addition of the following paragraph: Resilient connectors, installed according to the manufacturer's instructions, may be used to connect inlet and outlet pipes to concrete drainage structures Installation of Frames, Grates or Covers Subsection of MTC Form 407 is deleted and replaced by the following: The manholes and catch basins shall be constructed or installed so that the surface on which the bricks or adjustment units are to be placed is at least 75 mm but not more than 150 mm below the bottom of the frame and grate or cover assembly. Any combination of bricks, precast concrete adjustment units and rubber adjustment units may be used to set the frames and grates/covers on manholes and catch basins at the required position and elevation. A minimum of one rubber adjustment unit shall be used in all installations where the frame and grate/cover is located within the driving area of the pavement. The total height of the rubber adjustment unit(s) must be greater than 25 mm and less than 75 mm. Rubber adjustment units can be used in combination with concrete adjustment units or brick; the rubber adjustment unit must form the final surface for the seating of the frame and grate/cover assembly. Bricks or concrete adjustment units must not be placed on top of rubber adjustment units. July 2010 Pg. 2 of 5 SSP407S06

3 Rubber adjustment units shall be bonded to adjacent surfaces by laying a continuous strip of butyl tape on the top surface of the concrete adjustment units or brick course. The rubber adjustment unit shall be seated firmly in place, ensuring that it is centred over the structure opening. If more than one rubber unit is used, a continuous strip of butyl tape is to be laid between each rubber adjustment unit. A continuous strip of butyl tape shall be applied to the top surface of the rubber adjustment units and to the bottom of the frame. The frame shall then be set firmly in place ensuring that it is properly centred over the structure opening. If only brick or concrete adjustment units are used, or any combination of both, the frames for grates and covers on manholes and catch basins shall be set in a full mortar bed. If bricks are used, the inside and outside surfaces of the bricks shall be parged with a 12 mm thick mortar coat. Gratings for ditch inlets shall be installed and fastened down as specified in the contract. Frames and grates which are within the flow lines of the curb and gutter system shall be installed in accordance with OPSS 353 and shall not be part of the work of constructing cast-in-place manholes or catch basins or supplying and installing precast manholes and catch basins Adjustment and Rebuilding of Manholes, Catch Basins and Ditch Inlets General Clause of MTC Form 407 is deleted and replaced by the following: The work to be carried out shall include changes of elevation of any of the above structures, regardless of type or size. Prior to adjustment or rebuilding, the existing frame and grate/cover, lift rings and rubber adjustment units shall be removed and salvaged. When salvaged components are in reusable condition, they shall be cleaned of all mortar, sealants, rust and dirt. The manhole, catch basin or ditch inlet shall be adjusted or rebuilt using these salvaged components; otherwise, new components shall be installed so that the frame and grate/cover is set to the correct elevation. When manhole covers are to be raised only to accommodate resurfacing of the adjacent pavement, the Contractor may use manhole cover lift rings to raise the manhole grate or cover a sufficient height to accommodate the thickness of resurfacing material. Lift rings may be placed on top of each other to a maximum height of 140 mm. Only one type of lift ring or lift device shall be used for each structure. Bricks may be used to raise structures by a maximum of 300 mm which includes any extension of structures previously constructed using bricks. The inside and outside surfaces of the bricks shall be parged with a 12 mm thick mortar coat. Precast concrete adjustment units may be used to raise structures a maximum of 1.0 m which includes the extension of structures previously constructed using precast concrete adjustment units or a combination of bricks and precast concrete adjustment units. A minimum of one rubber adjustment unit shall be used in all installations where the frame and grate/cover is located within the driving area of the pavement. The total height of the rubber adjustment unit(s) shall be July 2010 Pg. 3 of 5 SSP407S06

4 greater than 25 mm and less than 75 mm, which includes any extension of structures previously constructed using rubber adjustment units. The maximum total extension of structures shall not exceed 1.0 m which includes any extension of structures previously constructed using any combination of adjustment units and bricks. All existing mortar and brickwork shall be removed from the top of the existing structures prior to adjustment or rebuilding with adjustment units. Additional manhole steps shall be required when the distance from the adjusted elevation of the structure to the first step would be in excess of 0.6 m. Where bituminous or concrete pavement must be removed to adjust or rebuild a structure, the pavement shall be removed according to OPSS Cast-in-Place Units Clause of MTC Form 407 is amended by the deletion of the three paragraphs under "Adjustment" and their replacement with the following: The adjustment of manholes, catch basins, or ditch inlets by raising will apply where the tops are to be raised by 1.0 m or less. The adjustment of manholes, catch basins, or ditch inlets by lowering will apply when the tops may be lowered to the required elevation by the removal of bricks, the removal of adjustment units, the removal of the mortar bed in which the frame was set, and by the removal of a maximum of 50 mm of the concrete walls of the structures. Where tops are to be lowered, the concrete shall be carefully removed to the required elevation Precast Units Clause of MTC Form 407 is amended by the deletion of the three paragraphs under "Adjustment" and their replacement with the following: The adjustment of precast manholes, catch basins, or ditch inlets by raising will apply where the tops are to be raised by 1.0 m or less. The adjustment of manholes, catch basins, or ditch inlets by lowering shall only apply where the tops may be lowered to the required elevation by the removal of bricks, the removal of adjustment units, and the removal of the mortar bed in which the frame was set. Adjustment units, bricks or manhole cover lift rings shall be removed or added as required, to adjust the structure to the proper elevation BASIS OF PAYMENT Manholes, Catch Basins and Ditch Inlets Subsection of MTC Form 407 is deleted and replaced by the following: July 2010 Pg. 4 of 5 SSP407S06

5 Payment at the contract price for the various tender items, "Manholes, Catch Basins and Ditch Inlets" shall be full compensation for all labour, equipment, and materials; for all earth excavation; for the removal of pavement, curb and gutter, and sidewalk except where there is a separate item for removal of pavement, curb and gutter, and sidewalk which overlaps pavement, curb and gutter and sidewalk removal required for placement of manholes, catch basins, and ditch inlets; for the management of surplus excavated materials; for the placing and compacting of granular bedding and backfill; for the construction or installation of the cast-inplace, precast or corrugated steel pipe units, and for the installation of inlet and outlet pipe, for the installation of concrete manhole tees with concrete risers, for the installation of corrugated steel pipe manholes with saddle plates and corrugated steel pipe risers and sewers larger than riser; for the installation of the frame and grate or frame and cover; for the placing of the full mortar bed; for the placing and parging of bricks; for the application of butyl tape; and the placing of adjustment units; except where such installations are part of the work of constructing curb and gutter and for all other work necessary to complete the structure in accordance with the contract. July 2010 Pg. 5 of 5 SSP407S06