The proposed extension/building works
Your development involves a single or double storey residential extension, conservatory, annexe or garage which is attached to the existing property
If total coverage of the public sewer(s) (foul, surface water or both) exceeds 6 metres (including pipe work already build over).
X Your development involves the construction of a new residential property, the extension of industrial and commercial property or any detached ancillary buildings or structure
X The pipe diameter, direction material or gradient changes beneath the area of the proposed build
X The size of the pipe is 300mm in diameter or larger
X Detached ancillary buildings or structure
X If you are unable to relocate the access point, i.e. access is on junction of sewers or a change of direction
X Your proposal involves an infill structure from one boundary to another where there are already structures on both sides
X Pressurised pipes such as rising mains and water mains
Are you aware of any historic blockages flooding, odour or other operational issues with the sewer/lateral drain
You are not aware of any historic blockages, flooding, odour or other operational issues with the sewer/lateral drain
You have had reason to contact Southern Water or another drainage professional as a result of problems with the sewers or lateral drains within your property within the last 12 months and these have not been repaired as yet
There are no easements or restrictive covenants which would prohibit building
You are not aware of easements or covenants which relate to the pipework which you propose to build near/ over
You are aware of easement/covenants which relate to the pipework which you propose to build near/ over
You are aware of easement/covenants which relate to the pipework which you propose to build near/ over
The sewer or lateral drain
is
a gravity flow pipe
The pipe freely flows and is
not
pressurised
This can potentially be
resolved if the sewer can
be diverted and the
customer is prepared to
enter into Sewer Diversion
Agreement in
accordance with S.185
Water Industry Act 1991.
The pipe is a pressurised
main
The pipe’s internal
diameter
If the pipe has an internal
diameter of 150mm (6 inch) or
less
If the pipe has an internal diameter of 150mm (6
inch) or less, consent will be issued via letter, if approved. If the pipe’s internal diameter is
225mm (9 inch), consent will be issued via agreement, if approved
If the pipe’s internal diameter is
larger than 225mm (9 inch)
The pipe material
Clay, concrete, ductile iron
Non-compliant pipe material can potentially be resolved if the pipework is replaced before building works begin
Pitch fibre, brick, asbestos cement, plastic not able to withstand 4000 psi jetting pressure
Current pipe condition
Pipe is in good condition. This can be established by exposing the length of pipe which is being built over or close to, or the completion of an internal CCTV survey
Poor pipe condition, which can be resolved if the pipe is repaired or replaced
The pipework is found to be defective and is not repaired
The pipe consistency under the new building
The pipe does not change in
diameter, direction, material or
gradient beneath the proposed
new building
Minor pipe inconsistency can potentially be resolved by carrying out agreed minor amendments before building works begin
Diameter, direction, material or
gradient clearly changes
beneath (or close to) he
proposed new building
Depth of the pipe from the existing ground level to the pipe channel (invert)
2.0 metres or less
Consent for building works over or near sewer
and lateral drains which are deeper than 3m, will
be issued via agreement or money in lieu. Please fill in the build over Application
Sewer depth is greater than 3 metres
Existing access points This relates to manholes, inspection chambers and rodding eyes
Your building will not be over the existing access point and is a minimum of 500mm from the
new build
Inaccessible access point issue can be resolved if the affected access can be repositioned or the shape of the build/extension is adjusted to meet this requirement.
You are unable to meet the
minimum 500mm clearance
requirement or the existing
access will be under the new
building
Overall length of pipe
(sewer / drain) with no
external access
You do not intend to build across the full width of your garden. If you do, external access to the sewer is available via the adjacent neighbour’s garden
If you intend to build full width of the garden and there is no external access to the sewer then consent will be issued via agreement. Any existing access points will need to be maintained by carrying out agreed minor alterations.
You intend to build across the full width of your garden and your neighbours have also done the same.
The type of foundation
which you intend to use
Your building relies on traditional strip or trench fill foundations.
A detailed assessment of the foundation and its
impact may be needed. Consent issued via
Agreement
Your building will use another
form of foundation design e.g.
pad, piling, raft, cantilever, etc.
Foundation positioning
Distance between the pipe and foundations
The foundation design protects the pipe where it passes nearby. The foundations which support the wall which do not cross the sewer, must have a minimum 500mm horizontal clearance between the edge of the new foundations and pipe
This can potentially be resolved after a detailed assessment of the foundation and its impact on the pipe. Consent issued via Agreement
Your foundation design cannot achieve 500mm clearance from the pipe or does not satisfy detailed design assessment criteria
Depth of your foundation in
relation to the pipe
Your foundations are designed
to be at least 150mm below the
pipe when located within 1m
(horizontally) of the pipe
Alternative foundation proposals will require a
consent issued via Agreement
Required foundation depth
cannot be achieved
Protecting the pipe where walls/foundation are built and cross over.
Your foundation design complies with the Standards set out within H4 Building Regulations and Southern Water Services design criteria.
The minimum lintel requirements cannot be achieved
Distance between the floor of the new building and pipe
Your design incorporates a
minimum of 300mm headroom
between the underside of the
new floor slab and the pipe.
Insufficient vertical headroom can potentially be resolved if the sewer can be diverted and the customer is prepared to enter into Section 185 Sewer Diversion Agreement Water Industry Act 1991
Your design cannot provide 300mm of headroom between the underside of the new floor and the pipe and the sewer diversion option is not practicable.