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					3           SANITARY SEWER COLLECTIONS


    3.1              ................................................................................................................ 1
              DEFINITION
               3.1.1        Public         Systems
                                    Sewage ...........................................................................                1
               3.1.2                 Sewage .........................................................................
                            Private Systems                                                                                           1

    3.2NON-PERMITTED
              FLOWS
                 ..........................................................................................                           1

    3.3      LOCATION
                   AND
                     ALIGNMENT
                           ....................................................................................                       1
              3.3.1           Sewers
                       Sanitary onPrivate          Property  .................................................                        2
                                                                                                                               : ......

    3.4      DRAINAGE/SUB-DRAINAGE
                          AREA ..............................................................
                             PLANS                                                                                                   2

    3.5 EXTERNAL
              SEWERSHED AND
                    LIMITS DRAINAGE .....................................
                                 AREAS                                                                                               2

    3.7PEAKING CALCULATION
            FACTOR   ...........................................................................                                      2

    3.8      DESIGN ......................................................................................................
                 CRITERIA                                                                                                            3
              3.8.1   Tributary Less 200 ...........................................................
                                 Areas Than ha                                                                                       3
              3.8.2   Tributary 200 and
                                 Area ha Larger            ............................................................              4

    3.9      PEAK CALCULATION
               FLOW     ......................................................................................                       5

    3.10 MANNINGS
              ROUGHNESSCOEFFIClENT
                        ..................................................................                                           5

       PIPE .................................................................................................................... 5
    3.11 SIZE

    3.12 FLOW ........................................................................................................
           VELOCITY                                                                                                    6
          3.12.1  Minimum   and Maximum   Velocities  ...........................................................      6
          3.12.2           Grades
                  Minimum ...................................................................................... 6

           MATERIAL
    3.13PIPE    .............................                                                                                         6
                                                               ~............................................................................

    3.14 PIPEDEPTHBEDDING ....................................................................
                  AND    MATERIAL                                                                                        7
           3.14.1        ..................................................................................................
                    Minimums                                                                                             7
           3.14.2   Maximumof Cover
                         Depth           .........................................................................       7
           3.14.3         Clearances
                    Crossing         ................................................................................ 8
           3.14.4   Minimum
                         Distance   between .........................................................
                                             Sewers                                                                      8

    3.15 MAINTENANCE
                 HOLES
                    ..............................................................................................                  8
          3.15.1            of               Holes
                   SpacingMaintenance.................................................................                              8
          3.15.2   Precast                 Hole
                             MaintenanceSizing           Criteria   ................................................                9
          3.15.3   Maintenance   Hole Diameters  ...................................................................                9
          3.15.4                Hole  Tees
                   Maintenance ...........................................................................                          9
          3.15.5   MaintenanceFrame Covers
                                 Hole          and          ....................................................                   10
          3.15.6   Watertight                  Hole
                                MaintenanceLids/Covers             ..............................................                  10
          3.15.7   Lockable                 Hole
                              MaintenanceCovers           .......................................................                  10
                                Hole  Steps
          3.15~8 Maintenance ........................................................................                              10
          3.15.9                 Hole  Drop
                   Maintenance Structures                ........................................................                  11

             and
Environmental EngineeringServices Department
              of
TheCorporation the City of London
Updated: December2005
              3.15.10 Maintenance  Hole  Safety  Landings   ........................................................        11
              3.15.11 Benching................................................................................................
                                                                                                                            11
                            in
              3.15.12 StepsBenching     .................................................................................. 11
                                Units
              3.15.13 Adjustment.................................................................................... 12
                           Losses
              3.15.14 Head .......................................................................................... 12
              3.15.15 Maintenance Hole  Access  ......................................................................      14
                                   Hole            Below Line
              3.15.15.1 Maintenance Access Flood ..........................................                                 14
                                   Hole
              3.15.16 MaintenanceConstruction             Practices   ..............................................        14
              3.15.17 New Subdivisions................................................................................... 15
              3.15.18 Sampling/Inspection                   Holes
                                             Maintenance ................................................                   16
                    b) Location                                                                                             16
                                 ......... : .....................................................................................
                    c)         Size
                         Minimum    ...................................................................................... 16

  3.16             DRAIN
             PRIVATE CONNECTIONS    (PDCS)   .............................................................                 16
             3,16.1         .................................................................................................
                      Location                                                                                             16
             3.16.2         Size Grade
                      Minimumand .......................................................................                   17
             3.16.3   Connections  to Sewers/Maintenance      Holes   ...........................................          17
             3.16.4         Clearance
                      Vertical         .................................................................................. 18
             3.16.6     Risers
                      PDC ............................................................................................18
             3.16.7     Cleanouts
                      PDC         ...................................................................................... 18
             3.16.8      Material
                      Pipe       ..........................................................................................18
             3.16.9       and         ......
                      Depth Bedding .......................................................................... 18
             3.16.10 NewSubdivisions ................................................................................... 19

            ......... .................................................................................................... 19
  3.17 EASEMENTS
        3.17.1             of
                     TypesEasements      .............................................................................. 19
        3.17.2               Easement ....................................................................
                     Minimum Widths                                                                                        20




          and           Services
Environmental Engineering      Department
  CorporationtheCityof London
The        of
       December
Updated:       2005
3          SANITARY SEWER COLLECTION SYSTEM


           DEFINITION

                       Systems
           Public Sewage

           A pipedcollection system that transports wastesof domesticorigins whichis human
           bodywaste,toilet or bathroom                                 and
                                          waste,wastefrom other showers tubs, liquid or
           water borneculinary and sink water or laundry waste, and suchother wasteas is
           suitable for treatment at a sewage treatmentfacility in accordance with City of
                                                 and
           LondonWasteDischargeBy-law WM-16 Drainage By-law No. WM-4.

3.1.2                   Systems
           Private Sewage

           A sewage        (or
                    system systems),with a total designcapacity of 10,000litres per day
                                                                      in
           or less, shall be designed,constructed,operatedandmaintained accordancewith
           Part 8 of the OntarioBuildingCode.

           A sewage       (or
                    system systems),with a total designcapacitygreater than 10,000litres
                              the
           per day,falls under jurisdiction of the Ministryof the Environment.


3.2        NON-PERMITTEDFLOWS

           Connectionsfrom foundation, weepingtile drainage or roof drainage are not
                                                                    with City of London
           permitted to enter the sanitary sewersystem, in accordance
           Drainage By-law No. WM-4,or any hazardouswaste as defined under the EPA
           Regulation347.


3.3        LOCATIONAND ALIGNMENT

           Generally                are
                    sanitary sewers to be locatedin front of, or are in locationsaccessible
                                                                  are
           to eachlot andblock facing a City street. Sanitarysewers also to be located1.5
           metres from the centreline of the road (see DWG.     U.C.C.-1Mfor details and
                                                         are
           additional designinformation). Sanitary sewers to be locatedon the inside loop
           of a proposed                              hole
                         crescentwith the maintenance locatedat a 1.5 metreoffset from
           the centrelineof the road.

          Wherea maintenance   hole is designed to be located within the vicinity of a
          roundabout,sanitary maintenance holes are not permitted to be located within the
          grassedarea of the roundabout. Sanitary maintenanceholes mustbe located in the
                                                  purposes.
          asphaltareaof the street, for maintenance




Environmental EngineeringServices Department
             and                               3-1
              of
TheCorporation the City of London
Updated: December2005
3.3.1                    on
           Sanitary Sewers Private Property

           Sanitary sewerson private property are regulated by the Ontario Building Code
           (OBC).Where                                             details from this manual
                       there are no specific regulations in the OBC,
           will apply.


3.4                            AREAPLANS
           DRAINAGE/SUB-DRAINAGE

                                 area                                         for
           Drainage/sub-drainage limits for whichsewersare to be designed are to
                                                               maintenance
           contain andfollow the lot/block lines to the proposed         holeslocated on
           the R.O.W.
               ’                                         for
           Note: All areas and populations are to be shown eachdrainage/sub-drainage
                 areas.


3.5               SEWERSHED
           EXTERNAL       LIMITS AND DRAINAGEAREAS

           Whendesign abuts undevelopedor un-serviced areas, identify       the external
                  limit to be designed
           sewershed                 for.

                                                         for
           Note: a) All areasandpopulationsare to be shown all drainageareaswithin
                                      limits; and
                     external sewershed

                                                                    to
                  b) For newsubdivisions, referencesshouldbe made the Subdivision
                     Development  GuideManual  SectionE.14 for additional design
                     information required for.new developments.

3.6        DESIGN CHART

          Sanitary sewerdesign calculations for approveddrainage area plans are to be
                    on
          completed the standarddesignchart. SeeFigure 3.1 for details andadditional
          designinformation.



3.7        PEAKINGFACTORCALCULATION

                factor calculations are to be determined
          Peaking                                           on        formula:
                                                       based the Harmon

                           Harmonformula M = 1 + 14
                                                    4+
                           Where M= ratio of peakflow to averageflow
                                P = tributary populationin thousands




Environmental EngineeringServices Department
             and                               3-2
              of
TheCorporation the City of London
Updated: December2005
3.8       DESIGNCRITERIA

                          the
          For determining peaksanitary flows contributing to a sanitary sewer,different
                                         on
          criteria are followed depending the size of the catchment area. Theseareasare
          defined as those less than 200hectaresandthose greater than 200hectares.


3.8.1     Tributary AreasLess Than200ha

          When        for
              designing parcelsof land less than 200hectares,the following criteria will
          apply:

         a)                      &
               ResidentialCommercialInstitutional

              i)      Zoning
                         LowDensity= 30 Units/hectare@3 people/unit
                              Density = 75 units/hectare @2.4 people/unit
                         Medium
                         HighDensity= 150-300 units/hectare @1.6 people/unit

               ii)    Lot Basis
                         Single Family= 3 people/unit
                                       =
                         Semi-detached 6 people/unit

               iii)   Area Basis
                         Single Family= 30 units/hectare@3 people/unit
                                        =
                         Semi-detached30 units/hectare @3 people/unit
                                                         2.4
                         Multi-family = 75 units/hectare@ people/unit

              iv)                            =
                      Commercial/Institutional 100people/hectare

              v)      ElementarySchool= 400 people

              vi)             School = 1500people
                      Secondary

                         =
              vii) Church 100 people/hectare

              viii) PerCapitaFlow= 250litres/capita/flow

              ix)                       Factor = 1.1
                      UncertainDevelopment

              x)      PeakingFactor = Harmon

              xi)                       litres/hectare/day
                      Infiltration = 8640                (0.100I/s/ha)

                                      are
                       Note:Theabove maximum   densities from the City of London   Official
                            Plan.Thedensity maybe adjusted by the City Engineeras more
                                             available on a specific parcel of land.
                            informationbecomes




          and           Services
Environmental Engineering      Department 3-3
  CorporationtheCityof London
The        of
       December
Updated:       2005
                b) Industrial

                                  -
                   i) FlowAllowance light industrial = 20,000litres/hectare/day
                                    - heavyindustrial = 50,000litres/hectare/day

                          Note:Theabove        density is from the City of London
                                         maximum                                    Official Plan.
                               The densitymay be adjusted by the City Engineer as more
                                                available on a specific parcel of land.
                               informationbecomes

                   ii)                        Factor = 1.1
                            UncertainDevelopment

                   iii)     PeakingFactor= 0.8 x Harmon

                   iv)                        litres/hectare/day
                            Infiltration = 8640                (0.100I/s/ha)

3.8.2      Tributary Area200ha andLar.qer

           When        for                        and
               designing parcelsof land 200hectares larger, the followingcriteria will
           apply:

           a)                        and
                  Residential,Commercial Institutional

                   i)       Population         =
                                      Allowance 55 peopleper hectare(gross areawith
                            any ESAareas netted out)

                 Note: Theabovemaximum density is from the City of LondonOfficial Plan.
                                     be                               as
                       Thedensity may adjusted by the City Engineer moreinformation
                             available on a specific parcel of land.
                       becomes

                    ii) Per CapitaFlow= 250litres/capita/day

                   iii)     PeakingFactor= Harmon

                                         Factor = 1.0
                   iv) UncertainDevelopment

                                            8640
                   v) Infiltration Allowance= litres/hectare/day(0.100I/s/ha)


           b) Industrial

                   i)                  =
                           FlowAllowance 30,000litres/hectare/day

                 Note: Theabovemaximum                                    Official Plan. The
                                         density is from the City of London
                                  be                                as
                       density may adjustedby the City Engineer moreinformation
                       becomesavailable on a specific parcel of land.

                   ii) PeakingFactor=0.8 x Harmon

                   iii)                      factor= 1.0
                           Uncertaindevelopment


Environmental EngineeringServices Department
             and                                    3-4
              of
TheCorporation the City of London
Updated: December2005
                                         8640
               iv) Infiltration allowance= litres/hectare/day(0.100I/s/ha)



3.9       PEAK FLOWCALCULATION

                                                  based the following formula:
          Peakflow calculationsare to be determined    on

          PeakFlow(Q) = populationX per capita flow X peakingFactor(H) X uncertain
                   factor + infiltration
          development

          Where:       Peak Flow (Q)         L/s
                       Per Capita Flow = 250litres/capita/day
                       PeakingFactor (H)     Harmon (section 3.7)
                       UncertainDevelopmentFactor = 1.0 or 1.1 (situation dependant)
                                            =
                       Infiltration Allowance 8640litres/hectare/day (0.100L/ha/s)


3.10                      COEFFICIENT
          MANNINGSROUGHNESS

                                                                  pipe for pipe sizes
         A coefficient of 0.013 is to be usedfor all concreteandPVC
               to         A
         200mm 1650mm.coefficient of 0.011is to be usedfor all pipe sizes 1800mm   or
         greater.


3.11     PIPE SIZE
         Pipe size is determined                     the
                                usingthe formulawhere pipe designflow is equal to or
         greaterthan the calculatedpeakdesignflow:
          1/2 1/n x A x R2/3x S
          Q=

         Where: Q = Designflow (m3/sec.)
                n = Manning’s roughness coefficient
                2)= crosssectional areaof flow (m
                A
                R=hydraulic radius (area/wetted  perimeter)
                S = slope of pipe (m/m)-

                       the               allowablesize of a sanitary sewershall be
         Notwithstanding above,the minimum
         200 mm.

                                       size                        shall be 100mm,
         Onprivate property, the minimum for sanitary building sewer            in
                   with
         accordance Part 7 of the OBC.




          and           Services
Environmental Engineering      Department 3-5
  CorporationtheCityof London
The        of
       December
Updated:       2005
3.12      FLOWVELOCITY

                                     shall be calculated
          Velocities in sanitarysewers                  usingthe followingformula:




                    V
               Where: = flow velocity (m/sec.)
                                flow
                     Q = Design (I/sec)
                     A =2)crosssectionalareaof flow (m

3.12.1           and    Velocities
          Minimum Maximum

                   velocity permittedin sanitary sewers 0.6 m/sec.
          Theminimum                                  is

                   velocity permittedin sanitary sewers 4.5 m/sec.
          Themaximum                                  is

                    velocities based actual flow, refer to Figure3.2 "Hydraulic
          Todetermine              on
                 Graph Circular Pipe".
          Elements    for

3.12.2    MinimumGrades

          a)   The minimum  grade on a 200 mm    diameter sanitary sewer is 0.33%. Where
                                                             to
               there are only a few dwelling units connected the uppersection of a 200mm
               sanitary sewer,the minimum grades shall be adjustedas follows:

               1 to 5 units             0.61%
               6 to 8 units             0.52%
               9 to 12unit              0.43%
               13 or more  units        0.33%

         b)    Theminimumgradeon all other sewersizes shall be establishedby determining
                         gradenecessary achievea velocity of at least 0.6m/sec.
               the minimum             to


3.13      PIPE MATERIAL

         Bothrigid and flexible pipe are permitted in the construction of sanitary sewer
         systems including private drain connections.Thesematerials include concreteand
         polyvinylchloride.

                                                                      Standard
         Thecriteria for these materials are describedin City of London      Contract
                   -
         Documents Section 410.05.01.

                                                                 and            shall
         Onprivate property, materialsfor sanitary building sewers private sewers
         complywith Part 7 of the OBC.



         and            Services
Environmental Engineering      Department 3-6
  CorporationtheCityof London
The       of
       December
Updated:       2005
             PIPE DEPTHANDBEDDINGMATERIAL

             Minimums

             Theminimum  depth of a sanitary sewershall be 2.4 m from the finished ground
                      to
             elevation the obvertof the pipe.

 3.14.2            Depth of Cover
             Maximum

             a). ConcretePipe

                  i)        SeeCity of London SW-I.0andSW-I.1for details andadditional design
                                                 standards ClassA, B andC beddings.
                            informationfor bedding       for

                          Proiects
              ii) Municipal

                 The maximum allowable cover permitted on concrete pipe to be constructed
                 under a Municipal or Capital WorksProject is to be basedon OPSD  807.01,
                 807.03, 807.04and 807.05.

                        the
                 Where pipe required exceedsthe OPSD          charts, the Pipe Pac Program2000
                             utilizing the following
                 will be used,                      variables:

                                                                to
                       ¯ all units are in metric andconform C.S.A.standards
                       ¯ wall thickness is basedon C.S.AA257.2M,         TypeB wall
                       ¯ soil density = 2000kg/m3
                       ¯ Ontario HighwayBridge Design Code(OHBDC)
                                                       =
                                  live load magnitude 25 tons
                       ¯ projection ratio = 0.70
                       ¯ lateral pressure  ratio = 0.33
                       ¯ lateral pressure friction ’m’ = 0.70
                       ¯ settlementratio = 0.70
                       ¯ k-mu(p) = 0.1924
                       ¯ variable bedding   factors B - Lf = 1.9 C - Lf = 1.5
                            rsdp= 0.49(calculated)
                       ¯ factors of safety
                               0.3mm  crack D-load = 1.00
                               ultimate earth andlive load = (ASTM 76M)C
                                                     =
                               DL.03 < 100 N/m/mm 1.50
                                                     =
                               DL.03 > 140 N/m/mm 1.25
                                                                     =
                               DL.03between100 and 140 N/m/mm interpolated
                       ¯ positive projection embankment    installation
                       ¯ maximum                             on
                                   depth of cover is based transition width design
                       ¯ depth of groundis measured     from the ultimate finished groundelevation
                                         top
                           to the outside of pipe.




Environmental and Engineering Services Department   3-7
The Corporation of the City of London
Updated: December 2005
          iii)       NewSubdivisions

                      Thestructural designof concretesewers                as
                                                           being constructed part of a new
                                                      with
                      subdivisionare to be in accordance oneof the following:

                      ¯   the "Maximum   Depth of Cover over Pipe - Reinforced Concrete Pipe
                          Only’,, as per the Subdivision& Development GuideManual;
                      ¯                                      Variables)
                          First Principles(with City of London
                      ¯   Pipe PacProgram  (with City of LondonVariables)

                                                                          of
                 It shouldbe notedthat the City is currently in the process reviewingthe two
                          and                              in
                 standards will establisha single standard the future.

     b) Flexible Pipe

          Themaximumallowable cover permitted on flexible pipe is 10.5 m. Thefollowing
                types are to be used:
          bedding

                 ¯                         1                  SW-I.0)
                      for up to 4.5 m- Type (see City of London
                 ¯                        2
                      for up to 10.5 mType (see City of LondonSW-I.0)

3.14.3    Crossin.qClearances

         Thereare minimum   clearancesrequired whensanitary sewerscross other services.
                                     from                    to
         In all casesthis is measured outsidewall diameter outsidewall diameter.

            crossingover or undera stormsewer,230 mm
         When                                       clearanceis required.

         Whencrossing over or under a watermain, 450 mmdiameter or less, 150mm
                 is
         clearance required.

         When crossing over or under a watermain larger than 450mm   diameter, 600mm
         clearance is required. WaterEngineeringDivision must review and approvethis
         crossing.Referto Section7.4.7.2.

3.14.4   MinimumDistance betweenSewers

         The minimum distance betweensewers shall be 3.0 m as per drawing UCC-1M.
                    to
         Specialcases be reviewfor site specific designconstraintsanddepths.


         MAINTENANCEHOLES

         Spacin.q of MaintenanceHoles

         The maximum spacing betweensanitary maintenanceholes shall be 99 metres
         measuredhorizontally or 110 metres measured  vertically from the top of the
                  hole,
         maintenance to the springlineof the pipe, alongthe springline to the next


          and           Services
Environmental Engineering      Department 3-8
  CorporationtheCityof London
The        of
       December
Updated:       2005
                   hole                                        hole.
          maintenance andvertically to the top of the maintenance

          When spacingof a maintenance                                   hole should be
                                        hole dictates that the maintenance
          placed within the vicinity of a roundabout,sanitary maintenance holes are not
          permitted to be located within the grassed area of the roundabout. Sanitary
          maintenanceholesmustbe locatedin the asphaltareaof the street, for maintenance
          purposes.

3.15.2                    Hole
          PrecastMaintenance Sizinq Criteria

                                                   holes are based incoming outgoing
          All sizing of sanitary precast maintenance              on       and
                                                  to
          pipe sizes andshouldbe sized andconform Figure3.3.

3.15.3              Hole Diameters
          Maintenance

                           hole                 are
          Precastmaintenance diameterrequirements as follows:

         a)   1200 mm  Diameter
              See OPSD                 701.030 for details and additional design
                        701.010 and OPSD
              information.

         b)   1500 mmDiameter
                                     701.040 for details and additional design
              See OPSD701.011 and OPSD
              information.

         c)   ¯ 1800mm  Diameter
               See OPSD                 701.050 for details and additional design
                         701.012 and QPSD
               information.

         d)   2400mm  .Diameter
                                     701.060for details and additional design
              See OPSD701.013 and OPSD
              information.

         e)   3000 mmDiameter
              See OPSD                 701.070 for details and additional design
                        701.014 and OPSD
              information.

         f)   3600 mm  Diameter
              See OPSD                 701.080 for details and additional design
                        701.015 and OPSD
              information.

3.15.4             Hole Tees
         Maintenance

         Maintenance Hole tees are not allowed for any sanitary sewerless than 1200mm
         diameter, For sanitary trunk sewersgreater than 1200mm  diameter, refer to the
         stormsewersection 5.14.4.




          and           Services
Environmental Engineering      Department 3-9
  CorporationtheCityof London
The        of
       December
Updated:       2005
 3.15.5               Hole Frameand Covers
            Maintenance

           Maintenance  hole framesand covers are required for all maintenanceholes and
           shall conformwith OPSD 401.01. SeeOPSD 401.01for details andadditional design
           information.

           Note: Maintenancehole framesandcovers are to be clear of curb and gutters on
                      in                                          hole
                 bends the road for newconstruction. Maintenance framesandcovers
                 maybe located in the curb and gutter on reconstruction projects, only as
                 approved.

3.15.6                           Hole
           Waterti.qht Maintenance Lids/Covers

                                   hole
            Watertight maintenance lids are required when    sanitary maintenance  holes are
           located within overlandstormflow routes. These  locations are within flood plain
           areas, within gutter locations andwithin an easementand/or openspacearea where
           overland flow is directly over and or adjacent to the maintenance    hole lids.
           Watertight maintenance   hole lids are also required under sanitary surcharge
           conditions. (See City of LondonSW-5.3for details and additional design
           information).

                              hole
           Watertightmaintenance lids are not requiredunderthe following circumstances:
                  Where                                      hole
                          designdictates that the maintenance lids endup in the curb and
                                    it
                  gutter and where is possible to rotate the coneso that the maintenance
                  hole lid is clear of the gutter, the coneshouldbe rotated suchthat a water
                                 not
                  tight lid would berequired;

                          in                                              hole
                  Where, the profile designof the street, the maintenance is locatedin
                  the low point of an overland flow route, the maintenance   hole maybe in
                  standard location, but would be submerged   undera greater than two year
                  stormevent. Maintenance holeslocated in a standardlocation on streets that
                  carry an overland flow route with a continuousgrade, or cascadinggrade
                                    of                                 do
                  (even thoughsome these maybe briefly submerged) not require water
                  tightlids.

3.15.7                       Hole Covers
           LockableMaintenance

           Lockablemaintenance  hole covers are required to reduce accessby the public.
           Theycan be located throughpark blocks, openspaceblocks, pumping   stations or
           pollution control plants. See OPSD  401.06 for details and additional design
           information.

3.15.8               Hole Steps
           Maintenance

                     hole
          Maintenance steps are required for accessandare to conformwith oneof the
          following:

           a) MaintenanceHole Steps- Hollow
              SeeOPSD        for
                      405.010 details andadditional designinformation.

Environmental EngineeringServices Department
             and                               3-10
              of
TheCorporation the City of London
Updated: December2005
                        Hole Steps- Solid
           b) Maintenance
              SeeOPSD       for
                      405.020 details andadditional designinformation.

                                               steel or aluminium;
           Note:a) All stepsare to be galvanized                 and

                b)    A detail or restorationplan is requiredfor the relocation of maintenance
                       hole stepswithin existing maintenance holes, where
                      applicable; and

                c)     Maintenance  hole steps shall be located to avoid conflict with an
                       inletting or outletting sewer           to
                                                    pipe. Access maintenance holesmustbe
                              the
                       above benching     platform.

3.15.9              Hole DropStructures
          Maintenance

                                                the
          Sanitarydropstructuresare requiredwhen differencein invert elevations
          betweenthe upstreamand outlet sewersin the maintenance  hole is equal to or
          greater than 0,6 metres.(SeeCity of London     for
                                                    SW-2.0 details andany additional
          designinformation).

3.15.10             Hole Safety Landings
          Maintenance

          Maintenance hole safety landings are required at the mid-point depth of the
          maintenance            the
                     hole, when depth of the maintenance                    5.0
                                                              hole is between and 10.0
          metres. Additional safety landings are required at third-point depths, whenthe
          maintenancehole is equal to or greater than 10.0mto 15.0mdeep. SeeCity of
          London       for
                SW-2.5 details andadditional designinformation.

                       pipes are to be belowsafety landings, where
          Note: Incoming                                          possible.

3.15.11   Benchin.q

          All maintenance                       at
                         holes require benching the bottomof the maintenance     hole and
          should conformto OPSD 701.021.Benching   height should be increasedto obvert to
          increasehydraulicbenefit as required.

          Note: Wherebenching is different              701.021, a benching detail is
                                                from OPSD
                required.

3.15.12   Stepsin Benchin.q

          Stepsin maintenance              are           the
                               hole benching required when pipe diameteris greater
                     and          to                 the
          than 900 mm benched springline, and when pipe diameteris greater than
                and         to
          450mm benched crown.SeeCity of London            for
                                                     SW-5.2 details andadditional
          designinformation.




          and           Services
Environmental Engineering      Department 3-11
  CorporationtheCityof London
The        of
       December
Updated:       2005
3.15.13 Adiustment Units

                      hole
           Maintenance adjustment                                         holes to ensure
                                      units are required on all maintenance
           that proper grade is provided betweenthe top of the maintenance   hole and the
                      hole
           maintenance lid. Ensure                                       the
                                      that the difference in gradebetween maintenance

                                                              600
           hole lid and the first ladder rung doesnot exceed mm.SeeCity of London         SW-
           5.0 for details andadditionaldesign                                        for
                                              information.Claybrick will not be allowed use
                           hole
           as maintenance adjustment      units.



3.15.14    HeadLosses

           a) Generally, whenvelocities    in the downstream pipe from a maintenance  hole
                      a                                                for
               exceed velocity of 1.2 m/s, headlossesmustbe accounted in the designof
               the sewer.In order to absorbhead lossesthat mayexist in maintenanceholes, it
                   be          to                      in                hole
               may necessary improvethe benching the maintenance or increase
               the size of the downstream  pipe wherepossible. Loweringthe crown of the
               outgoing sewerbelow the crownof the incomingsewerby the amount     equal to
                                      is                        of            for
               the headloss, however, the mosteffective method accounting headloss
               in mostcases.


          b)   Drops in maintenanceholes to compensatefor HeadLoss (HL) shall
               calculatedusingthe followingformula:

                        HL= KL. ~
                                V              Where   KL = Head loss coefficient
                              2g                        V = downstream velocity
                                                        g = 9.8 m2/sec

                                                             for
                    Note: AlsoseeFigure3.4 for quick reference headlossesin
                                    holes.
                          maintenance


                 loss coefficients (KL)are to be appliedas follows:
           c) Head

                    90 de,qrees
                              or                 they are only up to springline.
                    Nobenching deflector, or where
                    KL =1.5

                ii) 90 deqrees
                           or                  of
                    Benching deflector to crown sewers.

                    KL= 1.0




Environmental EngineeringServices Department
             and                               3-12
              of
TheCorporation the City of London
Updated: December2005
                   iii) Less than 90 deqrees
                        Multiply the head                                bend a head
                                          loss coefficient for a 90 degree   by     loss ratio
                        factor fromthe followingchart:

                             1.5
                             1.4

                             1.2

                             1.0


                       K~    0.8

                             0.6

                             0.4

                             0.2

                              0
                                          0.2        0.4           0.6       0.8   1.0
                                                           Qu/Qo




                   iv)   Junctions

                       - Tee
                                             to                            inlets.
                         Outletat right angles inlets andno deflectorbetween
                         K,= 1.5

                                           inlets for full heightandwidthof incoming
                            Deflectorbetween                                       flows.
                             =
                            KL 1.0

                      - Sideandcrossjunctions
                                            fromthe following chart:
                       Valueof KL is obtained


                                   1.0


                                   0.8

                                   0.6
                                                                         /
                                   0.4
                                                           /
                                   0.2


                                      0
                                                /
                                                0    15            30        45    60    75   90
                                                             IN
                                                    DEFLECTION DEGREES




Environmental and Engineering Services Department           3-13
The Corporation of the City of London
Updated: December 2005
                                                                          (radius pipe),
                 v) For KL valuesfor calculating headlosses in curvedsewers
                    seeFigure3.5.



3.15.15             Hole Access
          Maintenance

          a)   A 3.0m to 4.6m wide asphalt with granular base access is required for
               maintenancevehicles and equipmentused to access and service sanitary
               sewerswithin easements,openspaceareas, designatedblocks and existing
                                                      curvesandturn-aroundfacilities are
               right-of-ways (i.e. boulevards).Adequate
               required for maintenance                     Slopes(10%maximum),
                                        vehicles to maneuver.                      cross-
                                  and
               falls (2%minimum) drainageof accessroadsare also to be addressed thein
               design.

          b)   Where                          holes are installed belowthe flood line, the
                      sanitary sewermaintenance
                                                                          be
               engineershall be consultedandaccessroad alternatives may considered      in
               this situation.

               Note: a)                                      the
                          A 0.3mseparation is required between maintenance   accessand
                                        of
                          the top/bottom anyslopes;fences;andpropertyline(s); and

                     b)   Thedesign and construction of sewermaintenance  accessroads in
                          City ParksandOpen Spaces will require the review andapprovalof
                                                                   &
                          both ParksPlanningandthe Environmental EngineeringServices
                          Department.Wherever possible, seweraccessroads in City Parks
                          and OpenSpaces shall be integrated into the public openspace
                          pathway        and
                                 networks respectthe City’s natural heritage features.

                                    requirements.
          SeeSection 3.17 for easement


                    Hole AccessBelowFlood Line
3.15.15.1 Maintenance

          Where                          holes are installed belowthe 100year flood line,
                 sanitary sewermaintenance
                                                                         be
          the engineershall be consulted,andaccessroad alternatives may considered     in
          this situation.
                                      hole                  to
          In this situation, maintenance lids mustconform 3.15.6.


                  Hole Construction Practices
3.15.16 Maintenance

          a)    The void between the sewer pipe and the cored hole of the precast
                            hole
                maintenance section shall be filled with cement  bricks and approvednon-
                                                      holes will be allowedbut only with
                shrinkable grout. Pre bootedmaintenance
                                 by
                previousapproval the City.




          and           Services
Environmental Engineering      Department 3-14
  CorporationtheCityof London
The        of
       December
Updated:       2005
           b)                          hole                                     rubber
                 All precast maintenance section joints shall contain an approved
                 gasket.

          c)                      bricks are to be completely
                 All joints between                                            mortar.Bricks
                                                            filled with concrete
                 are to be pargedon the outside. Pargingshall contain an approved   bonding
                 agent.

          d)     All mortar and approvednon-shrinkablegrout shall be mixedand placed in
                           with
                 accordance the manufactures  specifications.

          e)                300 vertical/horizontal clearance betweenopenings on the
                 A minimum mm
                                        hole                      and
                 inside of the maintenance is requiredfor all sewer PDCconnections.

          f)    All maintenancehole frameand covers shall be adjusted to the finished road
                               of
                grade by means metal shims at each corner or by meansof an approved
                precastadjustment                                         x       (3"
                                 ring. Metalshimsare to be at least 75 mm 200mm x 8")
                                                      by
                andtheir thickness is to be determined the adjustment   required. Thespace
                        the
                between bottomof the maintenance    hole frameand cover and the top of the
                                   hole                   the
                precast maintenance is to be at minimum thicknessof oneadjustment

                                       300
                 unit and at maximum mm.See City of LondonSW-5.0for details and
                 additional designinformation.

          g)     Whereadjacent maintenance   holes are located in close proximity to one
                                         the
                 another, the area between adjacentmaintenance    holes shall be backfilled
                              with
                 in accordance the specificationsin the followingtable:

                      Distance Between
                    Adiacent Maintenance
                                       Holes                         Material

                              or
                    0.6 metres less                             concreteor crushedstone

                    0.6 metresto 2.4 metres                     granularmaterial

                    morethan 2,4 metres                         approvednative material or
                                                                granularmaterial

                                                              to
                 Theabovenotedbackfill shall be compacted the standardProctor Density
                                                            by
                 specifiedin the soils report, or as approved the City Engineer.

3.15.17   NewSubdivisions

          Reference should be madeto .the Subdivision & Development  Guide Manual,
          Section E.07 and E.14 for additional design information required for new
          developments.




Environmental EngineeringServicesDepartment
             and                              3-15
              of
TheCorporation the City of London
Updated: December2005
                                       Holes
3.15.18 Samplin,q/Inspection Maintenance

          a)   Requirements
               Sampling/Inspectionmaintenanceholesare typically requiredwhereInstitutional,
                          and
               Commercial Industrial developments   outlet to sanitary sewers owned   and
                          by
               maintained the City. Sampling/inspection  maintenance holesare required for
                                         sites.
               all industrial andcommercial

          b)   Location
                                              Maintenance
               If required, Sampling/Inspection           Holesshall be locatedon private
                                                                             by
               propertyas closeas possibleto the propertyline, or as approved the City
               Engineer.

          c)   Minimum  Size
               Sampling/InspectionMaintenance                       of
                                              Holesshall be a minimum 1200mm
                                                   Hole    be
               diameter.A larger diameterMaintenance may required if notedon the
               Building PermitApplicationDrawings.

               Sampling/Inspection            Holesthat havemorethan oneinlet sewer
                                    Maintenance
                                 in
               shall be increased size to ensure                      of
                                                that there is a minimum 0.9mbenching
                                of
               lengthdownstream all inlet sewers.

               Maintenance                      standards- see Section 3.15.3, and Figure
                            Holesshall be to OPSD
               3.7 for furtherdetails.



                                  (PDCs)
           PRIVATEDRAIN CONNECTIONS

           Location

                to                          lots are to be locatedin accordance
           PDCs single family andsemidetached                                 with
                        SW-7.0.
           City of London

                to
           PDCs multi-family (town housing, row housingand apartments),commercialand
                                                               hole on the R.O.W.See
           industrial blocks are to be connectedto a maintenance
           section3.16.3for further details.

          PDC’sshall be installed at 90° to the sewer main wherepossible. Underno
          circumstanceswill flow from the PDC enter the mainagainst the flow in the main.
          Where                             are
                horizontal or vertical bends required, long radius sweeps  shall be used.
                                                                       lot
          Short bendsare not acceptable.Single family and semi~detached Sanitary PDC’s
                    be           to
          shall NOT connected a maintenance      hole.

          Note: Where designconstraints arise (ie: top endof cul-de-sacor crescent), PDCs
                mayhaveto be located in reverse location and identified as such on the
                servicing drawings.




Environmental EngineeringServices Department
             and                               3-16
              of
TheCorporation the City of London
Updated: December2005
3.16.2 MinimumSize and Grade

          a)   Theminimum                         for
                         diameterand gradeof a PDC residential, single family and
                           lots is 100 mm 2.0%.
               semi-detached             @

          b)   Theminimum           gradeof a PDC a residential multi-family block
                         diameter.and           for
               is 150 mmdiameter @1.0%.

         c)    Theminimum                         for
                         diameterand gradeof a PDC a non-residential block is 150
               mm diameter @1.0%.

         d)    Theminimum                        for         block is
                         diameterandgradeof a PDC a commercial
               150 mmdiameter @1.0%.

         e)    Theminimum                         for
                         diameterand gradeof a PDC an institutional block is 200mm
               diameter @1.0%.

                                            requiredfor multi-family, nonresidential,
               Note: Theactualsize of the PDC
                              and                                on
                     commercial institutional blocksis dependant the flows.

3.16.3                                  Holes
          Connectionsto Sewers/Maintenance

         a)    Residential

               PDCs100 mm          in
                           and 150mm diameter must be connectedto the main sewer.
                              are
               Nosanitary PDCs to be constructed                           hole.
                                                into any sanitary maintenance

         b)                         Institutional andIndustrial
               Multi-family,Commercial,

                   200 in                                  to
               PDCs mm diameterandlarger are to be connected the mainsewerat
                         holes.
               maintenance

         c)             to              for
               Connections ExistinqSewers Lot Infill Situations

                                     a               or
                 In a situation where lot severance lot infill conditionexists, anda new
                                                     to
                 sanitary service will be connected an existing sanitary mainline, the
                          of
                 advocate the severance/infill, or his agent,must         if
                                                                 determine the existing
                                               or
                 sanitary seweris a combined poorly separated   sewerandis therefore at
                                      or             is
                 risk of surcharging, if the sewer a dedicated                 but
                                                                 sanitary sewer has a
                 history of surcharging.This information can be obtainedfrom Wastewater
                 Engineering                             that
                             Division. If it is determined there is a surcharge risk, the
                 development advocate must provide surcharge protection to his
                 development.

                 Whenconnecting PDC’sto existing sewersin a lot infill situation,
                 connections must be made utilizing      an approved saddle or
                 premanufacturedtee, in accordancewith OPSS                by
                                                            410, as amended the
                 SupplementalStandardsfor Sewerand Water(SW)in the City of London
                 Standard                 for
                         Contract documents MunicipalConnectionProjects.


          and           Services
Environmental Engineering      Department 3-17
  CorporationtheCityof London
The        of
       December
Updated:       2005
 3.16.4 Vertical Clearance

           A minimum clearanceof 150 mmunder/overthe storm sewerandwatermainis to be
           provided.

            Note:   For PDCsthat cross over or under a watermain larger than 450mm
                    diameter, 600 mm clearance is required. Water Engineering Division
                    must review and approvethis crossing. Refer to Section 7.4.7.2 for
                    furtherdetails.

3.16.5     PDCDetail

                     connection the mainshall be as per City of London
           Typical PDC         to                                    SW-6.0.

3.16.6     PDCRisers

           a) mv~el
                        for
               Required sewerdepthsgreater than or equal to 4.5 mandfor excavations in
               stable bankconditions, see City of London          for
                                                          SW-6.1 details andadditional
               design information. When  the PDC installed between45° and 67.5°, an
                                                  is
               approved                   joint shall beinstalled at the tee.
                       controlledsettlement

          b)
                        for
               Required sewerdepthsgreater than or equal to 4.5 mandfor excavations   in
               unstable bankconditions, see City of London          for
                                                            SW-6.2 details andadditional
               design information. When  the PDC installed between45° and 67.5°, an
                                                  is
               approved                   joint shall be installed at the tee.
                       controlledsettlement

3.16.7     PDCCleanouts

                 PDC                                                              to
           Where cleanoutsare required within the right-of-way, they shall conform SW-
           6.3. Onprivate property, sanitary building sewersand private sewersshall be
                                             holes, in accordance
           provided with cleanouts/maintenance                   with Part 7 of the OBC.
                              holes
           Cleanout/maintenance shall be locatedoff of the right-of-way.

3.16.8     PipeMaterial

           Referto Section3.13.

3.16.9     DepthandBeddin,q

          Theminimum  depth of a sanitary PDC shall be 2.4 metresfrom the finished property
                                                   The
          line elevation to the obvert of the PDC. maximum    cover on a sanitary PDCshall
                  on
          be based the following:

          a)   ConcretePipe
               The maximum                                           is
                            allowable cover permitted on concrete PDCs to be as per
               Section3.14.2a).

             and
Environmental EngineeringServicesDepartment   3-18
              of
TheCorporation the City of London
Updated: December2005
           b)   Flexible Pipe
                Themaximum                                         is
                            allowablecover permittedon flexible PDCs to be as per Section
                3.14.2b).

3.16.10    NewSubdivisions

           Reference should be madeto the Subdivision & DevelopmentGuide Manual,
           SectionE.11for additional designinformationrequiredfor newdevelopments.

3.16.11                            Service Connections
           Markin,q andRecordin.qPDC

           Brown                           X
                 painted surface stakes40mm 90mm(standard2" X 4") shall be placed after
                                    the                          These
           trenchrestoration to mark terminationof sanitary PDC’s.    stakesshall
           extendfrom PDC                  450mm
                           invert to minimum    abovefinished boulevardgrade.

                  or
           Plugged capped  service connections              on
                                              shall be marked the top surfaceof the
                                 end
           last 3mof the upstream of the pipe with yellow PVC  adhesivetape (50mmwide)
                              in
           labeledcontinuously black lettering (40mm wide)
           "CAUTION SANITARYSEWER"



3.17       EASEMENTS

                     are                                  by
           Easements required for all sewersto be assumed the municipality located
                                on              property.
           outsidea roadallowance privately owned

                       is
           Aneasement requiredto ensurethe municipalservices andutilities crossingthe
           site can be properly installed and maintained by the appropriate authority
           (municipality or private). Aneasement providesthe right to use private land for
                          which in the public’s interest.
           specific purpose     is

           All manholes                        require hard surface access. Refer to
                        located within easements
                         for
           Section3.15.15 hardsurfacedetails.

3.17.1     Typesof Easements

          a)     Municipal(Servicinq) Easements

                                                and
                 Are required for sanitary sewers accessroadsthat cross a site andwhich
                                by
                 are maintained the City.

          b)     Utility Easement

                                 are
                 Utility easements required for telephone,hydro, gas andcable television
                 services. Each utility company should be consulted for their specific
                 requirements.




Environmental EngineeringServices Department
             and                               3-19
              of
TheCorporation the City of London
Updated: December2005
           c)   Private Easements

                                    are
                ¯ Private easements required for private sanitary sewersand access roads
                that cross a parcel of land to service other private lands. A joint accessand
                maintenance agreement between the interested parties shall be entered into.


           d)   Temporary Easements and Working Easements

                Temporaryeasementsare required for sanitary sewers and access roads that
                                                                    are
                cross a site temporarily. Theservices in the easement to be maintainedby
                the ownerof the services.

3.17.2   Minimum Easement Widths

           Easement widths are determined by the depth of cover from the centreline of the
           road/ground to the invert of a sewer or watermain. Fig 3.6 showshowan easement
           width is to be determined. The minimumwidth of a sewer easementat a depth of
           up 2.4 metres, shall be 4.8 metres (2.4 metres eachside of sewer).




            and
Environmental Engineering          Department 3-20
                            Services
The          of
   Corporation the City of London
Updated:December 2005
                  SANITARY SEWER COLLECTION SYSTEMS


                                  LIST OF FIGURES



FIGURE3.1               SANITARYSEWERDESIGNCHART


FIGURE3.2                HYDRAULIC       GRAPH
                                  ELEMENTS    FOR CIRCULARSEWERS


FIGURE3.3                     PIPE SIZES FOR PRECAST
                        MAXIMUM                    MANHOLES


FIGURE3.4                         IN         HOLES
                        HEADLOSSES MAINTENANCE


FIGURE3.5               KL VALUESFOR CALCULATINGHEADLOSSESIN CURVED
                        SEWERS


FIGURE3.6                             WIDTHS
                        MINIMUMEASEMENT


     3.7
FIGURE                                    HOLE - SANITARY AND STORM
                        SAMPLINGMAINTENANCE
                        SEWERS




Environmental Engineering
            and                    Department 3-21
                            Services
The          of
   Corporation the City of London
Updated:December 2005
                           I}DPULATION
                     RESIDENTIAL DENSITIES                           SANITARYSEWER  DESIGN ~HEET
              ,ECTABEBASIS
              TNE
                FOLLOWINGPOPULATION WILL W~IEN
                                         APPLY RESIGNING SEWERSI
                                ALLOWANCES             SAR[TARY            CITY OF LONDON                       DESIGNCRITERA
              LOW      (SINGLE-FANILY/SERI-UEYACHED
                 DENSITY                     = 30UNITS/HECTARE
                                                          e 3 PEOPLE/UNIY                                           = 250
                                                                                                                SEWAGE L[TRES/CAPITA/OAY
              EDIU~DENSITY(TOW~HOUSE/RD~DUSE)= ?5UNITS/HECTARE                                                          = 8640
                                                                                                                INFILTRATION L[TREDARECTARE/BAy
                                                          ~ 2.NPEOPLE/UNIT                                            FACTOR: I+14
                                                                                                                PEARINO    ~=
              RIGHDENSITY
                        IAPARTWENTS)          =150-300
                                                    UNI~r/NECTARE
                                                              e 1-6
                                                                  PEOPLE/UNIT                                                                            DATE:
              LOTBASIS                                                                                                         4+P’0.3                          BY:
                                                                                                                                                         DESIGNED
                   FANILY
              SINGLE                         = ~ PEOPLE
              OUPLEX
                   / S£gl                    = 6 PEOPLE PROJECTNAME:                                                                                        FILE
                                                                                                                                                       PROJECT NO.
                       LOCATION                            AREA                 POPUL~’RON              FLOWS
                                                                                                   SEWAGE                     DESIGN
                                                                                                                          SEWER                                         PROFILE
                                                   NETOR DELTA TOTAL PER                                                                                                  ELEVATION
                                                                                                                                                                      INVERT
            No.
         AREA           STREET               WANHDLE ROSS
                                        NANROLE    G    HECTARES    HECTARE LOT LOTS DELTA TO4AL INFILT
                                                              NECTARES~ PER          POP. POP     LIG
                                                                                                          TOTAL
                                                                                                           L/S  n
                                                                                                                              SLOPE CAP VELOCITY
                                                                                                                                    LID
                                                                                                                                              LENGOT IN
                                                                                                                                                   FALL        DROP
                                                                                                                                                                  IN                PEANING
                                                                                                                       PIPE~SIZ~                    SEWERHEADLOSS
                                                                                                                                                               ~ANNDLI              FACTOR




                                                                                CITY         OF LONDON

                                           SANITARY SEWERDESIGN CHART
DWG:                                                     DATE
       FIG. 3.1                                                      2005 08
                                  VALUESOF _#._#AND
                                  _                no_

                                                ff           n f

1,0   1,2   1.4,    1.6     1.~    2.0    2,2    2.4    2.6 2.8      3.0   3.2    3.4    3.6




                                                                             HYDRI C
                                                                                  ULI
                                                                               IL
                                                                             RAD S,. R




0     0.1   0.2    0.3     0.4    0,5    0,,6   0.?    0.8    0.9   1.0    1.1   1.2    1.3

                         HYDRAULIC ELEMENTS V, Q, A, AND R
                                                 V~ Q~ Af           R#




NOTE:

I. INFORMATION TAKENFROM THE AMERICAN
   SOCIETY OF CIVIL ENGINEERS( A.S.C.E.) MANUAL.




                            CITY OF LONDON

                                                       FOR CIRCULAR SEWERS
                          MAINTENANCE HOLE           MAX, PIPE sIZE     MAX. PIPE SIZE
                           INSIDE DIAMETER       FOR STRAIGHT THROUGH FOR RIGHT ANGLE
                                 (mm)              INSTALLATION (mm)  INSTALLATION (mmO
                                                                                  450
                                   1200
                                                      600~600
                                                                                   450
                                                                                   600
                                   1500
                                                      825~~825
                                                                                   600
                                                                                   825
                                                 1050
                                   1800


                                                                                   825



                                  2400

                                                                          ~       1.050


                                                                                   050


                                  30O0




                                                                                    50



                                  3600
                                                                                 ~
                                                                                  1650



                               3000 x 2400




      NOTES

      I.   ALL DIMENS[QNS ARE FOR CONCRETEPIPEo
  2,       ALL DIMENSIONS ARE IN MILLIMETRES
  3,       KNOCKOUTS FOR SMALL DIAMETER CATCH BASINS LEAD SIZES
           300mm OR LESS COULD BE PROVIDED IN ADDITION TO WHAT IS SHOWN.
  4.       INFORMATION TAKEN FROM THE ONTARIO CONCRETE PIPE ASSOCIATION
           (O,C,P,A,)



                                               CITY     OF       LONDON

MAXIMUM PIPE SIZES FOR PRECASTMAINTENANCEHOLES
DWG                     DATE
           FIG, 3,3               2002 12 17
                                    HEAD   LOSS   - m

            o   o   o   o   o   ?   OOo           0
        o


        o




    0
    Z




I
                                                                                 HL = KL  V~
                                                                                         2g
                                                                                 R= C/L RADIUS OF BEND- METRES
                                                                                             OF
                                                                                 D= DIAMETER LARGEST   PIPE - METRES

            1.2
               ~1
            ~,.,
            1.0
            0.9
            0.8
            0.’7
ZO          0.6
            0.5
0           0.4
~
Cl O.       O.~
            0.2
            0.1
~C
             0

                    0 :1 .2   Zl   6   8   10   12.   14   1.6   ~,8   20   22     .24     26   28   30




                                                           R/D

     [---
                              M~NIMUM                -               ~
                                     WIDTH OF EASEMENT FROMC/L OFSEWER METERS


                        0       1      2        3        4   5   6   7   8   9 10




                6


                7




      NOTES:


         MINIMUM EASEMENT WIDTH
         MEASURED FRDM C/L OF SEWER PIPE
         EG: 6TB n~a~ SEWER WITH INVERT 3.9 m
         BELOW FINISHED SURFACE ELEVATIDN -
         WIDTH OF EASEMENT REQUIRED = 3.6 ~
         EACH SIDE DR A TDTAL WIDTH DF 7,~ mo

         THROUGH FIELDS, OPENSPACE,  ETC,, 9.I ~mln. -
         3,0 m ON ONE SIBEOF SEWER  O/L AND 6.1 m
         ON THE OTHER, OR AT LEAST 3,0 m WIDER
         THAR THE MINIMUMW~DTH  OBTAINEDFROM
                                BY
         THIS CHART. AS REOUIRED THE ¢IT~ ENGINEER.




                                     CITY OF LONDON
i        "            MINIMUM EASEMENT WIDTH
DWG             DATE
        A                                          A




                                        DETAILS
                                        HOLE WITH MORE THAN
                                        ONE INLET DRAIN                          20 # GAL STEEL
                                                                                 EQUIPMENT RUNG
                              MAINTENANCE
                              HOLE STEPS

                                                                       ~            ,~/ __~LE__
                                                                                    i         ~
                                                                                                   MAINTENANCE
                                                                                                         STEPS



                          12001OR     ’                                      1200iOR
                          12001~ MIN ~A
                                                                       "---~
                                                       g               ,"~’-~-1200,L~__MIN
                                                                                 C)L
                              ,
                                                                           600 >i    ’         ,   I/2    PIPE

                              I

                                                              RIS~.~                     SECTION

                   SECTION A-A                                         SECTION B-B
      NOTES:

I)    DETAILS NOT INDICATED SHALL BE IN ACCORDANCE WITH CITY OF LONDON STANDARDS FOR MAINTENANCE HOLE
      CONSTRUCTION
2)    MAINTENANCE HOLE SHALL BE LOCATED ON PRIVATE PROPERTY AS CLOSE AS POSSIBLE TO THE PROPERTY
      LINE OR AS APPROVED BY THE CITY ENGINEER.
3)    1200mm DIAMETER, OR LARGER, PRECAST MAINTENANCE HOLE TO THE CITY OF LONDON STANDARDS
      IS ACCEPTABLE.
4)    LARGER MAINTENANCE HOLE SIZE WILL BE REQUIRED IF NOTED ON BUILDING PERMIT
      APPLICATION DRAWINGS.
5) MAINTENANCE HOLES THAT HAVE MORE THAN ONE INLET SEWER WILL BE INCREASED IN SIZE TO
   ENSURE A MINIMUM OF 900mm BENCHING LENGTH DOWNSTREAM OF ALL INLET SEWERS (SEE DETAILS ABOVE)

6) MAINTENANCE HOLE STEPS TO BE IN ACCORDANCE WITH OPSD-405.010 & OPSD-405.020
7) CLASS OF CONCRETE :30MPA AT 28 DAYS

      NOTE: ALL DIMENSIONS IN MILLIMETERS UNLESS OTHERWISE NOTED

                                         CITY   OF LONDON
                           HOLE SANITARY & STORM
         SAMPLINGMAINTENANCE
                                             SEWERS                                                 ’
     FIG 3.7.         DATE
                              2005 08