Drawings for Sewer and Water - City of London

Min 1.0m from edge of trench
Level ground /undisturbed surface
or if disturbed, to be compacted to 100%
S.P.M.D.D. and soil bearing capacity
to be measured
=l
Unshrinkable fill, minimum
0.6m below existing pipe
up to centreline. Depth of
unshrinkable fillto be
determined based on
size of existing wm,
Trenching to comply
with M.O.L. guidelines,
Existing ground
Existing Watermain
Cut into side slopes
0.6m in order to place
unshrinkable fill
Granular bedding
to be installed to
City of London Standards.
Proposed pipe to
cross existing wm.
label elevation of
pipe invert.
WPICAL REINSTATEMENT /BEDDING DETAIL CROSS SECTION
SEE DRAWING W-CS-69,_
SHEET 3 FOR REQUIREMENTS
Verify &
lableldepth
The watermain shall be protected by the following:
- When crossing under or over the watermain there must be a
minimum separation of at least 0.6m between the outside
diameters of the crossing pipes.
- A minimum 5.0m length of pipe shall be centered at the point
of crossing so that the watermain joints will be equidistance
and as far as possible from the sewer or PDC. Crossing must
be absolute minimum 2.0m from watermain joint.
- All construction methods including excavation and backfill
compaction within 0.6m of existing watermain shall be done by
hand.
It should be noted that the support structure is to remain in
place until the watermain is fully supported by the reinstated
bedding (i.e, until SMPa unshrinkable fill is cured, provide bond
break).
CITY OF LONDON STANDARD DRAWING
TYPICAL REINSTATEMENT /BEDDING DETAIL
FOR 450mm AND UP WATERMAIN SUPPORT