Series 4 of the Ontario Provincial Standards Drawing Manual contains a number of Standard Drawings which provide the designer with a choice of designs which may be slightly different from each other but not sufficiently different to prohibit their consideration as alternatives.
The Ministry's policy would be to provide the contractor a choice whenever the difference in the design is not sufficient to affect capacity and safety. However, in specific instances it may be necessary for the designer to specify one or the other design exclusively.
In the following discussion, the Standard Drawings in each grouping should be considered as possible alternatives for Ministry Contracts.
Catch Basin Grates
OPSD 400.01 - Catch Basin, Cast Iron, Frame and Dished Square Grate.
OPSD 400.04 - Catch Basin, Ductile Iron, Frame and Flat Square Grate, Overflow Type.
Both of these grates have a slot at the back of the grate which increases flow capacity and improves the grate's ability to be self-cleaning. The difference in capacity between the dished grate and the flat grate is not sufficient to affect catch basin spacing. There are lugs in the overflow to minimize the possibility of bicycles becoming caught in the slot.
The dished grate is generally used in conjunction with a combination curb and gutter where traffic does not travel directly over the grate. The flat grate is more appropriate where there is a curb only and the grate lies within the asphalt pavement.
OPSD 400.03 Catch Basin, Cast Iron, Frame and "V" Square Grate.
This grate is used in conjunction with "V" type gutter shown in OPSD600.01 TypeD.
OPSD 400.04 and OPSD 400.05 are cancelled.
These grates are no longer manufactured.
OPSD 400.02 - Catch Basin, Cast Iron, Frame and Flat Square Grate.
OPSD 400.06 - Catch Basin, Cast Iron, Raised Frame and Circular Grate, Flat or Dished Slotted Opening.
OPSD 400.07 - Catch Basin, Cast Iron, Raised Frame and Flat Circular Grate.
These grates have diagonal slots and no overflow. They are more suitable for locations where bicycles have access but have a reduced capacity because of the lack of overflow slot. The circular grates have intake characteristics similar to the square grates at relatively flat grades but are considerably less efficient at grades steeper than 0.01m/m.
When traversed by vehicles, the circular grates have a more stable seating in the frame and are not subject to the rocking that may occur in square grates.
OPSD 400.08 - Catch Basin, Cast Iron, Side Inlet Frame.
OPSD 400.09 - Catch Basin, Cast Iron, Curb Inlet, Over-flow Plate.
The use of side inlets in combination with grates is beneficial in sags as they are more self-cleaning and can be used in combination with flat grates with and without the overflow at the back of the grate. Side inlets used without grates are not efficient especially on grades. OPSD400.08 can only be used with the OPSD400.02 grating.
OPSD 401.01 - Manhole, Cast Iron, Cover & Square Frame.
OPSD 401.04 - Manhole, Cast Iron, Cover and Raised Square Frame.
These standard drawings each include a closed-type cover and an open-type cover. It is necessary to specify which cover type is required when quoting these standard drawing numbers.
OPSD 401.02 - Manhole, Cast Iron, Cover and Circular Frame.
This drawing includes only a closed cover, however, it does have eight small circular openings 25 mm in diameter. It is not used by the Ministry.
OPSD 401.03 - Manhole, Cast Iron, Watertight Cover and Square Frame.
OPSD 401.05 - Manhole, Cast Iron, Watertight Cover and Raised Square Frame.
These covers are used where infiltration of water cannot be tolerated.
OPSD 402.01 - Valve Chamber, Cast Iron, Circular Cover and Plug.
OPSD 402.02 - Valve Chamber, Cast Iron, Raised Frame with Circular Cover and Plug.
OPSD 402.03 - Three Piece Valve and Meter Chamber Cover.
Used where valve chamber covers are required.
Ditch Inlet Grating
OPSD 403.01 - Ditch Inlet Galvanized Steel, Heavy Cast Grating.
Used on all ditch inlet catch basins.
OPSD 404.01 - Safety Platforms, Aluminum for Square Manhole.
OPSD 404.02 - Safety Platforms, Aluminum for Circular Manholes.
To be specified as required on deep manholes.
Steps and Ladders
OPSD 405.01 - Manhole Steps.
This drawing contains all the various manhole steps which are approved for use. If for any reason a particular type is not appropriate for a specific installation, it would have to be crossed-out on the drawing.
OPSD 406.01 - Aluminum Ladder.
OPSD 406.02 - Steel Ladder.
Ladders may be an alternative to Manhole Steps. In that case it would be necessary to quote these standard drawings in the contract.
For corrugated steel pipe manholes, only the steel ladder may be specified.
Municipalities or utilities may have a preference, in which case the designer should choose the appropriate standard drawings.
In some cases the contractor may be given the choice of steps or ladders in which case all three standard drawing numbers should be quoted.
OPSD 804.01 Rev.1 Concrete Headwall for Sewer or Culvert Pipe CSP 900mm Dia. and Greater
OPSD 804.02 Rev. 1 Concrete Headwall for Sewer or Culvert Pipe CP 900mm Dia. and Greater
The formulae for reinforcing steel in TABLE1 for dimensions A1, A2, A4, A5 and A6 have been corrected.
If the original drawing has been used in a contract, it is necessary to check the figures in TableII to be sure they now agree with the new formulae.
November 18, 1992
OPSD 807.01 Rev. 1 Specified Minimum Class of Pipe - Reinforced Concrete Pipe
Table revised to limit pipe size to 1800 mm and to depict maximum cover in confined trench condition.
OPSD 807.03 Specified Minimum Class of Pipe - Reinforced Concrete Pipe
New standard drawing developed to depict maximum cover in positive and zero embankment condition.
OPSD 807.04 Specified Minimum Class of Pipe - Non reinforced Concrete Pipe
New standard drawing developed to depict maximum cover in trench and embankment conditions
These 3 OPSD's are to be used in all contracts advertised on or after November 18, 1992
OPSS 405 Feb,1990
Construction Specification for Pipe Subdrains
Scope: Rewritten to eliminate the detailing of undivided types of pipes
Definitions: Definition for Geotextile "knitted Sock", and subdrains added.
Construction: Agricultural or Vitrified Tile, and Bell and Spigot
Pipe have been deleted from the Text
Installation of subdrains have been revised
to include rodent gates.
No change to documentation.
104 S03 This special provision has been cancelled contents included in OPSS 405 dated Feb, 1990.
OPSS 405 is to be used in all contracts advertised after 91 04 01
The following Standard Drawings are implemented in all contrcts advertised after April 1, 1992.
New or Revised OPSD's:
OPSD 700.01 Rev. 1 OPSD 703.01 Rev. 1
700.02 Rev. 1 703.02 Rev. 1
700.03 Rev. 1 703.03 Rev. 1
700.04 Rev. 1 705.01 Rev. 1
701.01 Rev. 1 705.02 Rev. 1
701.02 Rev. 1 705.03 Rev. 1
701.03 Rev. 1 705.04
701.04 Rev. 1 706.01 Rev. 1
701.05 Rev. 1 706.02 Rev. 1
701.06 Rev. 1 706.03 Rev. 1
702.04 Rev. 2 707.01 Rev. 1
702.05 Rev. 2 708.01 Rev. 1
OPSD 702.01 OPSD 702.03
OPSD 701.03, 701.04 and OPSD 701.05 show the different components for designing Precast Concrete Manholes. In Rev'n 1 the section entitled "monolithic base" or "sump detail" depicting a 300 mm min sump has been deleted. The designer should make sure that these manholes are designed with a minimum sump of 300 mm.