Report to the Cabinet Member for Highways and Transport
Report submitted by: Executive Director for Environment
Date: 15 February 2012
Part I - Item No. 1
Electoral Divisions affected:
Skelmersdale East and
West Lancashire East
Drainage Works, Calico Brook, Appley Bridge and Dock Brook, Parbold
Contact for further information:
John Gatheral, 01772 534471, Environment Directorate,
john.gatheral@lancashire.gov.uk
Executive Summary
West Lancashire Borough Council and the Environment Agency are currently
developing drainage schemes to reduce the flood risk to communities in Appley
Bridge and Parbold. These schemes will benefit the County Council in terms of
reducing the severity and extent of highway flooding at a number of locations in
both villages. They may also however extend County Council responsibilities for
maintaining surface water culverts beneath the public highway. Lancashire County
Council is at risk of reputational damage if the works do not proceed because of
objections on their part.
Recommendation
The Cabinet Member for Highways and Transport is asked to agree that the
County Council accepts the proposals to install new lengths of surface water
culvert within the highway perimeter and to accept that responsibility for future
maintenance may then rest with the County Council.
This decision should be implemented immediately for the purposes of Standing
Order 34(3) as any delay could adversely affect the execution of the County
Council's responsibilities. The reason for this is to enable the works to be carried
out without delay.
Background and Advice
West Lancashire Borough Council (WLBC) is currently developing drainage
schemes to reduce the flood risk to communities in Appley Bridge and Parbold.
These schemes are being funded by the Environment Agency (EA), which has
indicated that it has a capital allocation to support the works if they are undertaken
this financial year.
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The proposed schemes, described in more detail below involve placing culverts
under the highway.
These lengths of culverts will be watercourses and almost without exception the
person who owns land adjoining the watercourse is responsible for that section of
watercourse – the riparian owner. The EA has powers in respect of, and will carry
out works on, watercourses known as main rivers but the status of riparian owner still
remains. Riparian owners have certain rights and obligations. Responsibilities
include passing on the flow without obstruction and accepting flood flows even if
caused by inadequate capacity downsteam. The EA explains it has various powers
to maintain and improve main rivers but the powers do not oblige it to carry out
maintenance. It has statutory powers of entry. The EA has powers to require riparian
owners to remove obstructions. It is advised that the surfaces of publicly
maintainable highways are vested in the County Council under S263 Highways Act
1980.
Under S14 Land Drainage Act 1991 a District Council can construct new
watercourses and could construct under highways. Considering the case law it would
indicate that the highway authority's interest in the surface would probably be found
by the courts to be sufficient to make it a riparian owner even for a section of a new
watercourse constructed by a drainage board in the sub soil. The powers to then
maintain it exist for the District but it does not have to use them but could instead
turn to the highway authority as riparian owner.
There is however provision for the drainage authority to pay full compensation for
injury sustained by persons affected (Section 14(5)). Case law indicates that this is
for physical damage but also diminution of value. Whether such compensation
should also cover future costs of inspection etc has not been adjudicated as far as
revealed by research to date. It is not expected that the culvert works will damage
the highway nor diminish value.
In both these schemes the public highway seems to be the most appropriate route
for the culverts but the schemes potentially leave the County Council with liabilities it
would not otherwise have had.
Appley Bridge
Calico Brook East flows west through Appley Bridge from Shevington. Calico Brook
North flows south along the Lancashire / Wigan local government administrative
boundary. They meet at the rear of premises on Mill Bank, where they become
Calico Brook, and are taken in a culvert through a small housing estate, built in 1971.
The first flood event came 6 weeks after the completion of the estate, when water
depths reached up to 500mm. There was a further flooding incident in 1984, but the
most notable event occurred in August 1987 when 41 houses at Mill Bank were
flooded to a depth of 2.5m. Interim measures were installed to reduce flood risk, by
diverting peak flow into an abandoned quarry, with the consent of the landowner.
The quarry is now the subject of a planning application and there are fears that this
long term, but temporary, agreement may be withdrawn. This will place the homes at
Mill Bank under substantial flood risk again.
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The Appley Bridge scheme consists of the construction of a 435m long surface water
culvert that will act in parallel with the existing system, which has significant capacity
constraints. The first 25m and final 100m of culvert will be installed in an open trench
and the intermediate 310m will be installed using tunnelling techniques.
Approximately 155m of the tunnel length will be installed under Mill Lane, the public
highway, in two lengths. The first length extends for 136m and is laid along the
length of the highway. The second length, 19m, is laid in a crossing of the highway.
Herons Wharf (public highway) is also crossed in tunnel, this time for a length of
11m. The total length of new culvert under the highway is 166m. The sub-surface
installation will clearly minimise impact on the travelling public. The works are
currently estimated to cost £1,100,000, funded by the EA.
The County Council's Commissioning Plan for West Lancashire identifies Mill Lane
as a length of highway subject to flooding. Whilst Mill Bank is not recorded as being
at flood risk, the 1984 event above is likely to have resulted in approximately 240m
of highway on the estate as being inundated, with the majority subject to the depth
identified above. It is anticipated that once the works are complete the flood risk and
severity will be greatly reduced. The works will also provide flood relief benefits to
communities in the Shevington area.
Calico Brook, and the North and East tributaries are currently identified as Ordinary
Watercourses. As such, they are the responsibility of the riparian owners, with WLBC
consenting works on them. The EA has indicated that once the new works are
complete it is likely that the existing and the new surface water culverts will be
designated as Main Rivers. Riparian owners will still be responsible for regular
maintenance of these features and ensuring that flows can pass unimpeded, but the
EA can also carry out work through DEFRA grants. The Main River status indicates
that the facility is a critical piece of infrastructure in the management of flood risk.
Because of the high risk and consequences of floods it is anticipated that EA is likely
to accept the old and new lengths of Calico Brook as Main River.
A number of other interested parties will be affected by the scheme, including private
landowners, Network Rail and British Waterways. WLBC intends to serve notice
under the Land Drainage Act to occupy private land and is negotiating with Network
Rail and British Waterways for permission to install apparatus beneath their facilities.
The progress of the works may clearly be affected by the willingness of these
parties.
WLBC is currently carrying out geotechnical investigation on and off the highway to
establish ground conditions for the open trench and tunnelled sections of the works.
Until the EA resolves the Main River status of the new surface water culvert,
maintenance will be the responsibility of the riparian owner. For the 166m length
under the public highway, this will initially at least, lie with Lancashire County Council
as Highway Authority.
Officers have reviewed the proposals for the culvert and it is considered that it is
intended to install it in accordance with current best practice. The works promoter
has completed "Approval in Principle" documents that aim to establish that a safe,
functional, economic design is achieved and constructed. The design will be certified
4
by a Principal in the design organisation. This approach follows the Highways
Agency position used for similar installations beneath trunk roads and motorways.
A condition has been made that the works do not temporarily or permanently
adversely affect the safety, stability and serviceability of the public highway. The
promoter is to establish a monitoring system during the works and for a period of two
weeks after the works to record any short term movements in carriageway and
footway ground levels. If necessary, remedial works would be carried out following
negotiations between the County Council, WLBC and the EA to restore the condition
of the highway.
Parbold
Dock Brook rises on Parbold Hill and drains and passes through the southern part of
the village before discharging into the River Douglas. There has been considerable
residential development in this area in the last 50 years and this has involved
alteration to its alignment and a number of lengths laid to culvert. The ground profile
of the upland catchment give rise to a rapid response to rainfall events which
coupled with the much flatter topography of the lower developed areas gives rise to a
high risk of flooding.
Prior to residential development in the 1960s and 1970s this area was farmed. Due
to its low lying nature and location, immediately adjacent to the River Douglas, it was
regularly inundated with floodwater. Residential development saw finished ground
levels raised to reduce this flooding. Since completion of the development there have
been two major storm events in 1987 and 2002 that have led to widespread flooding
of this area with roads not passable and internal flooding to property.
The Dock Brook works comprise the improvement of the open channel section
immediately downstream of the Southport to Wigan Railway Line; improving access
to and replacing defective lengths of surface water culvert around the Station Road
crossing; and re-aligning the downstream lengths of culvert to a new headwall on the
River Douglas. The first section of works, improvements to the open channel, has no
impact on Lancashire County Council's facilities. The works around Station Road do
not increase Lancashire County Council responsibilities as a riparian owner and will
in fact offer improved access for future maintenance works. The final section, realigning the downstream lengths of culvert, will see a new length of surface water
culvert installed beneath the public highway (West View), for a length of
approximately 30m. The works are currently estimated to cost £700,000, funded by
the EA.
The County Council's Commissioning Plan for West Lancashire identifies Burnside,
Station Road and Mill Leat Close as lengths of highway subject to flooding. It is
anticipated that once the works are complete the flood risk and severity will be
greatly reduced.
Dock Brook is currently identified as an Ordinary Watercourse and it is not
anticipated that its status will change following these works. Riparian owners will be
responsible for regular maintenance of the culvert in perpetuity. The new 30m length
of surface water culvert under the public highway will become a maintenance issue
for Lancashire County Council as Highway Authority and riparian owner.
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Consultations
Not applicable.
Implications:
This item has the following implications, as indicated:
Financial
If EA choose not to classify the re-aligned Calico Brook as a Main River then the
County Council will become wholly responsible for future maintenance and
inspection of the length of culvert that lies under the highway (166m). Classification
as Main River would see EA assume some responsibility for ongoing maintenance in
conjunction with the County Council. If the EA fail to take up their maintenance
duties and this action falls to the County Council as Highway Authority then it is
estimated that the ongoing maintenance costs for inspection and repair of this
structure is in the region of £1,250 per annum.
At Dock Brook, the new 30m length of surface water culvert under the public
highway will become a maintenance issue for the County Council as Highway
Authority and riparian owner. It is estimated that the ongoing maintenance costs for
inspection and repair of this structure is in the region of £750 per annum.
If the County Council became responsible for the funding of future inspections and
repairs on one or both culverts beneath the highway then it is anticipated that they
would be contained within the Directorate's existing maintenance budgets.
Risk management
If the County Council resists these works then there is a possibility of reputational
damage in the event of another significant flood incident in either or both villages.
The County Council's status as Lead Local Flood Authority would be undermined.
Legal
It is advised that the placing of the culverts under publicly maintainable highway
places the County Council in the position of riparian owner with liabilities for
maintenance of the culvert.
Any representations made to the Cabinet Member prior to the issue being
considered in accordance with the Public Notice of Forward Plans
Name:
N/A.
Organisation:
Comments:
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Local Government (Access to Information) Act 1985
List of Background Papers
Paper
Date
Nil.
Reason for inclusion in Part II, if appropriate
N/A.
Contact/Directorate/Tel