NOTES RELATED TO MANHOLE DETAILS:

1. 225mm Thick C30/37 Mass Concrete Foundations (Over 75mm concrete blinding if required by site conditions)

2. Preformed half circle Channel pipes. The pipeline may where practicable, be laid through the manhole and the

crown cut out to half diameter, provided flexible joints are situated on each side no further than 600mm.from the

inner face of Manhole wall.

3. For Surface Water Manholes high density blocks to Cl.S10 of I.S.20 Part 1: 1987 or Cl 30N/20 insitu conc.

Blockwork shall be bedded and jointed using Mortar designation three to I.S406. Beds and vertical joints shall be

completely filled with mortar as the blocks are laid. Joints shall be flush pointed as the work proceeds (Blockwork

not to be used in areas where a high water table is prevalent). All Foul Manholes must be faced in solid

Engineering Brick (min.class A or B), or in-situ concrete for 1 meter above benching level. Brick to be bonded to

Blockwork using English Garden Wall Bond.

4. Relieving arch formed by 215x103x65 brick as per drawing. Relieving arches used in brick or blockwork manholes

to extend over full thickness of wall. Double arch to be formed for pipe diameters greater than 600mm.

5. Benching and pipe channel pipe surround Cl. 20N/20 concrete.

6. Benching finished in 2:1 sand-cement mortar with a smooth trowel finish,at 1 in 30 slope towards channel. 25mm

radius Nose on Benching to be level with Crown of Pipe.

7. Standard rungs at 300c/c vertically and galvanised to BS 729.

8. 675mm square ope. in roof slab.

9. 225thk. Precast R.C Roof Slab in C30/37 Concrete. Cover to steel shall be 40mm.

10. 1 to 2 No.Engineering Bricks Cl.B to I.S.91:1983 set in 1:3 (cement sand mortar)

11. Class D400 manhole cover and frame to IS/EN 124.150mm deep frame for roads,100mm deep for footpaths and

green areas. Class B250 manhole covers can used in Private areas accessible to light vehicular traffic. Non-rock

design, closed keyways,manufactured from spheroid graphite cast iron (ductile cast iron), 675x675 (or 675diam.)

clear opening, cover and frame coated in bitumen or other approved material, cover to have a minimum mass of

140Kg/m2, frame bearing area shall be 80,000mm2 min., frames shall be designed to prevent covers falling into

manhole.Frames shall be bedded on approved mortar to manufacturers instructions.

12. Short length pipe, pipe joint external to manhole shall not exceed 600mm from the inner face of the manhole wall.

13. Toe holes of 230mm min. depth and galvanised steel safety railings to be provided in benching of sewers greater

than 525mm dia. and depth to invert>3M for access to invert.

14. Safety chain to be provided on pipes that exceed 450mm in diameter. Mild steel safety chain shall be 10mm

nominal size grade M(H) non calibrated chain, type 1. complying with B.S.4942 Part 2.

15. When depth of Manholes to invert is greater than 3.0M. ladders shall be used, instead of rungs 25mm in dia.

B.S.4211 except that stringers should be not less than 65x20mm. in section and rungs 25mm in diam.Fixed

Ladders should meet the dimensional requirements of B.S.4211.

16. Ladder stringers should be adequately supported from the Manhole wall at intervals of not more than 2.0m.

Stringers should be bolted to cleats to facilitate renewal.

17. All ladders,rungs,handrails,safety chains etc. shall be hot dip galvanised to B.S.729.

18. Socket of pipe should be cut flush with the inside surface of the manhole wall.

19. Position of 910 square ope in intermediate roof slab. All Manholes shall be watertight to the satisfaction of the

Engineer. Formwork to reinforced concrete and mass concrete shall comply comply to Class 2, Section 6.2.7

BS8110:Part 1:1997. Finish to the top of slabs shall comply to Type A, Section 6.2.7 BS8110: Part 1: 1997. Plan

dimensions of Manholes are based on blockwork having a co-ordinating size of 450x225x100. Manholes are

designed to B.S8005 and wall thickness to I.S325 Blockwork design reinforcement to slabs to Engineers details.

20. For Manholes >3m depth to invert use C30/37 in-situ concrete. Reinforcing mesh Ref.A393 @ 6.16Kg./m to be

fixed at mid point of wall. Additional reinforcement to be supplied over pipe crown. All brick to be Engineering

Brick.

21. For pre-cast Manholes, Chamber walls and cover slab to be constructed to IS EN 1917 and IS 420 2004.

22. Manhole opes to be situated furthest from the nearest Carriageway. Manhole steps/access to be positioned to

allow viewing of oncoming traffic.

23. For bedding and sealing of chamber rings, the top ring (to Pre cast cover slab) and bottom ring to be bedded with

cement mortar, For intermediate rings, joints to be sealed with approved pre-formed jointing strip.

24. Precast Manholes to be surrounded with a minimum of 150mm thick Grade C20/40 concrete.

150mm ope for SS Pipe

400

500

150

Backfill Around Gully with Cl 804

Stone to NRA Spec. for Roads

Work Compacted in Layers

Precast Concrete

Gullies are Not

Permitted in the

Dublin City

Council Area Gully to BS 2911

Internal dimensions -

450x300x900 Deep

1200 min.

Crown removed by cutting

to half diameter provided

flexible joints are situated

on each side no further

than 600mm from inner

face of Manhole walls

(See Note 2)

50

130

2+2T16-75

T12-150T12-150

2T12-150

T12-150

T12-150

Fixed ladders should

meet the dimensional

requirements of BS.4211

200 215 910 215 200

225

1340

910

910

1340

Details for pipe diameters

150, 225, 300, 375, 450mm

Depth to invert less than 1.0m

450

Max.

300

250

150

Safety Chain shown

for information.

Position chain on

downstream side only.

300

50

150

150

150 150

TYPE D

150

150

150

TYPE C

150 150

TYPE B

1 2

Ø

150 150

TYPE A

Concrete pipe beds and haunches may be required to address minimum cover situations, and shall be

subject to submission and assessment by Irish Water before advancing with the works. Concrete pipe

beds and haunches shall have a minimum thickness of 150mm with an absolute minimum depth of cover

above the external crown of the pipe of 750mm.Concrete to be in accordance with is EN 206 and to be

class C16/20.The haunches and surrounds to be formed using form work to provide a rough cast finish.

Expansion joints in the concrete shall be provided at all pipe joints to allow for pipe flexibility, compressible

filler board to be in accordance with BS EN 622-1 and BS EN 622-4, and to be 18mm thick.Polyethylene

pipes shall be wrapped in plastic sheeting having a composition in accordance with BS EN 6076 before

being cast into concrete. Bituminous material shall not be put in contact with PE or PVC pipes.

(A) Pipe

Diameter

ROADWAY

(B) Min. Trench Width

Backfill, refer to

Note C for details

(C

)300

See N

ote B

Marker tape, refer to

Note I for details

Pipe bedding, refer to

Note E for details

Road / Footpath Surface

GRASSED AREAS

Note F

Grassed Areas

PIPE DIAMETER

(A) mm

TRENCH WIDTH

(B) mm

< 80 Rising Main See Note 10

100 500

150 600

200 600

250 750

300 750

350 750

400 900

450 900

_

PIPE DIAMETER

(A) mm

BEDDING DEPTH

(C) mm

< 100 100

150 - 450 200

_

Plan

Scale 1:50

A

A

8

Flow

Section A-A

Scale 1:50

370

1

2

4

9

3

5

6

8

10

11

B

B

Flow

200 215 910 215 200

Section B-B

Scale 1:50

370 370

500 m

ax.

11

4

1

6

Rocker

Pipe

25mm

Chamfer

MANHOLE - TYPE A

1790

1360

A

A

B

B

Plan

Scale 1:50

MANHOLE - TYPE B

Flow

8

370

3

5

6

10

11

200 215 1360 215 200

Section A-A

Scale 1:50

1

2

4

9

7

8

50

200 215 1360 215 200

Section B-B

Scale 1:50

12

7

Flow

4

6

Conrete

surround to 1st

pipe typically

500 m

ax.

25mm

Chamfer

Details for pipe diameters

225, 300, 375, 450mm

Depth to invert 1m to 3m

2240

1590

A

A

1590

2240

B

B

Plan

Scale 1:50

Flow

8

MANHOLE - TYPE C

200 325 1590 325 200

Section A-A

Scale 1:50

1

2

9

2m

m

in. before shaft com

mences

where depth available

5

6

3

10

11

8

500 m

ax.

225

225

200 325 1590 325 200

Section B-B

Scale 1:50

1

1515

25mm

Chamfer

Details for pipe diameters

225, 300, 375, 450mm

Depth to invert 3m to 6m

Flow

613

Flow

1810

2240

B

2240

1810

A

A

8

300

750

Max.

200 325 1590 325 200

Section A-A

Scale 1:50

1

2

9

7

If depth to invert is more

than 1.8m provide

additional rung for safety

150

500 m

ax.

200 325 1590 325 200

Section B-B

Scale 1:50

1

25mm

Chamfer

Details for pipe diameters

525, 600, 675, 750mm

Depth to invert 1m to 3m

Flow

613

3

10

11

8

7

MANHOLE - TYPE D

B

Plan

Scale 1:50

14

Flow

1810

B

A

8

B

2460

1810

A

MANHOLE - TYPE E

Plan

Scale 1:50

150

200 325 1810 325 200

Section A-A

Scale 1:50

1

2

9

2m

m

in. before shaft com

mences

where depth available

5

6

3

10

11

8

500 m

ax.

225

200 325 1810 325 200

Section B-B

Scale 1:50

1

1515

25mm

Chamfer

Details for pipe diameters

525, 600, 675, 750mm

Depth to invert 3m to 6m

Flow

6 13

50

25mm

Chamfer

25mm

Chamfer

600

Safety Rail

Inlet Dia.

mm

H(max)

mm

225

300

375

450

525

600

750

600

600

750

750

750

750

750

INLET DIA.

mm

DROP DIA.

mm

225

300

375

450

525

600

750

300

375

375

450

600

450

450Where Drop 'H'

is greater than the

max. value shown,

use Back-Drop Manhole

Flow

A

A

1360

1790

1790

1360

Plan

Scale 1:50

150

13

H

200 215 1360 215 200

Section A-A

Scale 1:50

1

Flow

Stepped

benching

Ramp manhole for

pipe diameters

150, 225, 300, 375mm

Drop less than 750mm

MANHOLE - TYPE F (Ramp)

A

A

Flow

20

1

10

9

15

Safety

Rail

45°

bend

Rocker

Pipe

Backdrop manhole for pipe diameters

225, 375, 450, 525, 600, 750mm

Drop more than 750mm

Brick arch or PC

lintel for pipes

> 300mm

Flow

Flow

Plan

Scale 1:50

Section B-B

Scale 1:50

MANHOLE - TYPE G (Backdrop)

1m

to 3m

Integral in-situ 20/20 concrete base walls, benching and base slab with precast channel as

shown or in-situ formed inverts alternative. Walls to extend 150mm beyond outer faces of

chamber ring. Alternatively precast concrete chamber rings may be bedded in a mortar or

on in-situ 20/20 concrete base slab 300mm greater in diameter than chamber rings.

150

225

Platform

F

l

o

w

1

2

12

One or more pipe

bends (if required)

Plan on Curved Invert

Scale 1:50

PC manholes

are not permitted

in the Dublin City

Council Area

Platform

Flow

12

12

Plan on Straight Invert

Scale 1:50

A

A

B

B

Section A-A

Scale 1:25

13

2

14

5

R75mm

10

150

7

18

2

13

500 m

ax.

Flow

Section B-B

Scale 1:50

MANHOLE - TYPE J

Platform

F

l

o

w

1

2

12

One or more pipe

bends (if required)

Plan on Curved Invert

Scale 1:50

Platform

Flow

12

12

Plan on Straight Invert

Scale 1:50

A

A

MANHOLE - TYPE K

10

150

18

2

13

Flow

Section A-A

Scale 1:50

15

24

900

Taper section

or reducing slab

3m

to 6m

Refer to table

Integral in-situ 20/20 concrete base walls, benching and base slab with

precast channel as shown or in-situ formed inverts alternative. Walls to

extend 150mm beyond outer faces of chamber ring. Alternatively precast

concrete chamber rings may be bedded in a mortar or on in-situ 20/20

concrete base slab 300mm greater in diameter than chamber rings.

Platform

F

l

o

w

1

2

12

One or more pipe

bends (if required)

Plan on Curved Invert

Scale 1:50

Platform

Flow

12

12

Plan on Straight Invert

Scale 1:50

A

A

MANHOLE - TYPE L

Integral in-situ 20/20 concrete base walls, benching and base slab with

precast channel as shown or in-situ formed inverts alternative. Walls to

extend 150mm beyond outer faces of chamber ring. Alternatively precast

concrete chamber rings may be bedded in a mortar or on in-situ 20/20

concrete base slab 300mm greater in diameter than chamber rings.

10

150

18

2

13

Flow

Section A-A

Scale 1:50

15

24

900

Taper section

or reducing slab

3m

to 6m

900

2m

m

in.

6m

m

ax.

Hinged

grating Landing

Slab

Alternative Method of Forming

Channel Through Manhole

Scale 1:50

Flow

1

End of pipe

Safety chain

Plan

Safety Chain - Elevation

NTS

Detail of Access Ladder

NTS

6mm fixing bracket &

cleat, 2m max. ctrs.

Galvanised ladder

for depths over 3m

40mm cover to

reinforcement

In-situ Roof Slab - Plan

NTS

Gully Plan

Scale 1:50

A

A

Kerb

Traffic Flow

Gully positioned

close to kerb &

5mm below the

adjacent road level

Gully grating &

frame to IS.EN 124

Class D400

100mm min.

concrete surround

to gully chamber

150mm

concrete base

Saddle piece

Section A-A

150mm SS conc Pipe

Saddle piece

45° or 22

1

2

° Bend

as Required

Min. 100mm Concrete

Surround to Gully Chamber

150

300

GULLY TO COMBINED SEWER

GULLY TO STORM SEWER

Section

Scale 1:50

215mm 10N

blockwork, internal

dimensions

450x300mm

Gully positioned

close to kerb &

5mm below the

adjacent road level

Gully grating &

frame to IS.EN 124

Class D400

Double gullys to

have separate

connections to sewer

Heavy duty gully grating & frame

to BS.497 set 5mm below

finished channel level and bedded

haunch with cement mortar

Two courses Class B

engineering brick to

BS.3932 laid on

cement mortar

825

PRECAST CONCRETE GULLY PIT

Section

Scale 1:50

2460

1360

1790

PC manholes

are not permitted

in the Dublin City

Council Area

PC manholes

are not permitted

in the Dublin City

Council Area

20x65 stringer

595

3

6

0

1

3

5

0

9

0

°

150

1 2

Ø

PIPE BEDDING & BACK FILLING DETAILS

150

150

(A) Pipe

Diameter

(B) Min. Trench Width

(C

)

See N

ote B

Backfill, refer to

Note C for details

Marker tape, refer to

Note I for details

Pipe bedding, refer to

Note E for details

Steel chain in down

position secured

to restraining hook.

Position chain on down

stream side of manhole

(to be used for all

pipes 450mm and over)

GENERAL NOTES:

A. Read in conjunction with all relevant Architect's & Engineer's drawings and cross read the

detailed notes on the various manholes.

B. The minimum length of manholes are as shown, however this may need be increased subject

to the number of branches, this is made up as follows:

· For pipes up to 150mmØ, provide the sum of the branches + 200mm per branch + 300mm

· For pipes over 150mmØ, provide the sum of the branches + 300mm per branch + (300mm

if no pipes up to 150mm are used) eg: for 2x150Ø + 1x225Ø pipes on one side, length

=1525mm (subject to minimum length)

C. Access Rungs shall be provided in MH greater than 1000mm to the invert level of the pipe.

D. A 300mm concrete surround shall be provided around manhole covers in grassed areas.

E. All Manholes covers and gullies shall be approved Local Authority type and to their standard

pattern.

F. All Drainage work shall be Constructed Strictly in accordance with the requirements of the

Local Authority & Building Regulations.

G. Class U2 finish to the top of slabs. Reinforcement in the slabs to details or instructed by the

Engineer.

Standard Galvanised Rung

Scale 1:50

2

5

Ø

M

S

B

a

r

38mm min.

internal radius

on all bends

1

2

5

(

E

m

b

e

d

d

e

d

i

n

W

a

l

l

)

BEDDING & BACKFILLING NOTES:

A. The minimum depth of cover from the finished surface to the crown of gravity pipes without protection should be

as follows:

· Gardens and pathways without any possibility of vehicular access - depth not less than 0.5 m. (this would

normally relate to drains in private property, shallow pipes of this nature are undesirable and should be installed

in accordance with the current building regulations).

· Driveways, parking areas and yards with height restrictions to prevent entry by vehicles with a gross vehicle

weight in excess of 7.5 tonnes - depth not less than 0.75 m.

· Driveways, parking areas and narrow streets without footways (e.g. mews developments) with limited access

for vehicles with a gross vehicle weight in excess of 7.5 tonnes - depth not less than 0.9 m.

· Depths of sewers in gated estates shall be similar to that outlined above.

· Agricultural land and public open space - depth not less than 0.9 m.

· Other highways and parking areas with unrestricted access to vehicles with a gross vehicle weight in excess of

7.5 tonnes - depth not less than 1.2m.

B. Clause 808 material in accordance with the National Roads Authority specification for Road Works is to be used

as backfill material where the sewer main is located in roads, footpaths or when the nearest part of the trench is

within 1m of the paved edge of the roadway. Clause 808 is to be compacted as per Clause 802 of the NRA SRW.

C. Selected excavated material may be used in green-field areas above granular pipe surround material subject to

the approval of Irish Water.

D. Pipe bedding shall comply with WIS 4-08-02 and IGN 4-08-0 granular material shall be 14mm to 5mm graded

aggregate or 10mm single sized aggregate is en 13242. concrete bed, haunch & surround, where required, shall

be to STD-WW-08.

E. In soft ground conditions (cbr < 5) the material should be excavated and disposed of in accordance with the

waste management act and clause 808 material in accordance with the national roads authority specification for

road works shall replace the excavated material, wrapped in geo-textile wrapping. alternatively, special pipe

support arrangements, including piling etc. may be required where the depth of soft material is excessive. such

arrangements shall be subject to assessment by Irish Water before advancing with the work.

F. In green field areas, Type B backfill (selected excavated material) will be allowed above the side haunch granular

material in the case of rigid pipes. A granular surround of a minimum depth of 150mm above the crown of the

pipe is required for flexible pipes, and Type B material may be used as backfill above this. all rising mains in

greenfield areas shall have a minimum cover of 300mm of granular material above the external crown of the

pipe.

G. Pipes shall not be supported on stones, rocks or any hard objects at any point along the trench. rock shall be

excavated to a depth of 150mm below the actual depth of the trench with the void filled with clause 808 material

in accordance with the national roads authority specification for road works. the granular material shall be laid

above this void backfill material.

H. Non degradable marker tape should be installed at top of pipe bedding layer. In the case of non metal pipe

material, the marker tape should incorporate a trace wire which is linked to fittings and terminated at the waste

water pumping station and the discharge manhole.

I. Trench widths for pipe sizes ≤80mm may be <500mm, subject to consideration being given to the trench

depth, health & safety & construction access requirements.

DEPTH (m)

PIPE DIAMETER (mm)

225 300 375 450 525 600 675 750 900

0-1

1-3

3-6

150

A 910x910INSITU/BLOCK

PRECAST

INSITU/BLOCK

PRECAST

INSITU/BLOCK

PRECAST

- - - - -A 910x910 A 910x910 A 1360x1360 A 1360x1360

J 1050Ø J 1200Ø J 1200Ø J 1350Ø J 1350Ø J 1500Ø J 1500Ø J 1500Ø J 1800Ø PipeØ+900

1050 1200

- -

B 1360x1360 B 1360x1360 B 1360x1360 B 1360x1360 B 1360x1360 - - -

C 1590x1590 C 1590x1590 C 1590x1590 C 1590x1590 C 1590x1590

D 1810x1810 D 1810x1810 D 1810x1810 D 1810x1810

E 1810x1810 E 1810x1810 E 1810x1810 E 1810x1810 - - -

J 1050Ø J 1200Ø J 1200Ø J 1350Ø J 1350Ø J 1500Ø J 1500Ø J 1500Ø J 1800Ø

K 1200Ø K 1200Ø K 1200Ø K 1350Ø K 1350Ø K 1500Ø K 1500Ø K 1500Ø K 1800Ø

PipeØ+900 PipeØ+900

PipeØ+900 PipeØ+900 PipeØ+900

PipeØ+900 PipeØ+900 PipeØ+900

TABLE 1 - MANHOLE TYPES & SIZES

Drawing No. Issue

Drawing Title

A1 A

D14 CR20Dublin 14

CONSULTING ENGINEERS pogaRathfarnham

Tel +353 (0)1 205 1101www.poga.ie

Unit C2, Nutgrove Office ParkDrawing Status

Job No.

Project Title

Scale @ A1Date By Checked

ByRev. DescriptionDate

B C D E F G H I J K L M N O P

1

2

3

4

5

6

7

8

9

10

Architect

Pat O'Gorman & Associates

© This drawing is Copyright and must only be used for the project namedOrdnance Survey Ireland Licence No. EN 0055618 © Ordnance Survey Ireland / Government of Ireland

STRUCTURAL & CIVILEARLS COURTKILL, Co. KILDARE

JFOC ARCHITECTS

MAR 2020 AL NM AS SHOWN

SURFACE WATER MANHOLEAND DRAINAGE DETAILS

PLANNING

1715 113 P0