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Victoria Footbridge
Major Maintenance and Repair |
75.8% |
Whole Project Award
Project Team: Herefordshire Council (Client), Owen
Williams, Part of Amey plc (Designer),
Interserve Project Services Ltd (Contractor)
Site character
The Victoria Footbridge in Hereford is a Grade II Listed
structure and was built in 1898 to commemorate the Diamond
Jubilee of Queen Victoria the previous year. The three-span
suspension bridge carries a public footway / cycleway
over the River Wye close to Hereford city centre.
The bridge was temporarily closed in 2002 after a
hole appeared in the bridge deck, and further emergency
repairs were carried out in 2004. Detailed inspection
carried out without mechanical plant, on foot and using
rope access, revealed significant corrosion to structural
elements necessitating works beyond routine maintenance
to ensure public safety.
The works included:
- Restoration and repair of
structural elements affected by corrosion
- Strengthening structural elements
- Replacement of the bridge
deck
- Restoration and refurbishment
of the handrails, decorative features, approach pilasters
and concrete detailing at the top of the piers and
abutments
- Replacement and restoration
of lighting.
Project Management approach
CEEQUAL was heavily promoted from the outset of the
project to ensure a best-practice approach was adopted
by the whole project team, in addition to complying
with Environmental Management System (accredited to
ISO14001) requirements. A project environmental manager
was appointed during the design phase, which meant environmental
assessments and surveys were undertaken early on, thus
ensuring that they influenced the planning and design
process and that mitigation measures formed an integral
part of the design rather than being an add-on.
Biodiversity
The River Wye is designated as both a Site of Special
Scientific Interest (SSSI) and Special Area of Conservation
(SAC). Ecological surveys identified that bats were
foraging around the bridge, white-clawed crayfish were
present in the river and that the site was also important
for migratory and spawning fish. To minimise potential
adverse impacts, a range of mitigation measures were
incorporated including:
- Pursuing working methods that
avoided impacts on white-clawed crayfish, breeding
fish, and nesting birds
- Programming works to avoid
sensitive times of year
- Retaining all existing vegetation.
Trees immediately adjacent to the bridge were pollarded
as part of advance works avoiding the bird nesting
season.
- Full encapsulation of the
bridge to prevent any debris entering the river
- Lighting trials were undertaken
at night with Natural England present to make certain
that the lighting design avoided light spillage onto
the river, potentially disturbing foraging bats, migrating
fish or other aquatic life.
- During construction, safety
navigation lights were shielded to minimise disturbance
to aquatic habitat.
In addition to mitigation measures, a number of bird
boxes were provided to contribute to biodiversity enhancement.
Archaeology & Cultural heritage
Due to the presence of important archaeological sites
close to the bridge, the project team planned the site
compound location, access routes and working methodology
to avoid ground disturbance. This included using a temporary
floating pontoon to transport and install a working
platform instead of heavy plant.
The Grade II Listing of the structure reflected its
architectural and historic importance. It lies within
a Conservation Area and an Area of Archaeological Importance
and as such, the refurbishment works required the adoption
of a sympathetic approach to the restoration of the
Victorian features and careful choice of materials.
This was achieved through regular consultation with
the council’s conservation officer. The existing
paint on the bridge was investigated revealing many
layers. From this it was possible to determine and specify
the original paint colour for the repainting of the
steelwork.
Resource use
During the design phase options were considered on
sustainability and future maintenance grounds. Detailed
surveys were undertaken to ensure as much of the structure
as possible was preserved and re-used. The deck was
replaced with a new durable timber deck (similar to
the original bridge design) from an accredited UK sustainable
source. New components incorporated can be individually
handled and replaced in the future if required, removing
the requirement for heavy lifting equipment and expensive
access. The bridge steelwork was grit-blasted using
recycled grit-blast material to remove the 13 coats
of paint and rust. The lighting design for the project
incorporated low energy bulbs, which were linked into
a green energy supply.
Noise and vibration
Different forms of grit-blasting and blast material
were considered as well as plant used to reduce any
vibration impacts. A space frame below the bridge deck
and spanning between the bridge supports was used to
support the encapsulation and to eliminate intermediate
supports in the river. This, along with no plant on
the bridge, eliminated any vibration and disturbance
of the river bed.
Community liaison
Keeping the community informed on project progress
was considered important throughout. Members of the
project team attended local Area Forums, visited schools,
met with stakeholders, issued regular press releases
and participated in local radio interviews.
Following successful completion of the works, the
whole project team organised and participated in the
Civic Trust’s Heritage Open Day event (a national
event forming part of the European Heritage Initiative).
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