£16m surface water pumping station uses some of Europe’s largest
screw pumps to deliver water from the storm sewer network to the
by Rob Moffat, Pete McCann & Jonathan Pearson
Archimedean screw pumps, among the largest in Europe,
deliver water from the storm sewer network to the River Hull
- Courtesy of Black & Veatch
response to the 2007 flooding that affected thousands of homes
in the Bransholme catchment is now complete and operational.
This saw Yorkshire Water appoint Black & Veatch to carry out a
feasibility study followed by a design and build contract for a
new pumping station. The new Bransholme Surface Water Pumping
Station (SWPS), which more than quadruples the capacity of its
predecessor, became operational in July 2016 with a ribbon
cutting handoff ceremony in December. The ceremony took place
just a week after the station was put to the test by a weather
event with 8m3/s of storm flow, more than the 5.4m3/s the
original station was capable of handling. The SWPS handled the
flow with no problems, and the 15,000 nearby homes protected by
the station saw the first benefits of the project.
The 23.6m3/s Bransholme
Storm Water Pumping Station is located in Selset Way in
Kingswood, Kingston upon Hull. 8 (No.) Archimedean screw pumps,
among the largest in Europe, deliver water from the storm sewer
network to the River Hull and, in the event of high river flows
or tides, to a newly enlarged 111,000m3 lagoon for attenuation.
The water can then be released back to the River Hull after
weather conditions improve.
The station has already
been recognized by several engineering-related institutions for
excellence. However, the project team faced several challenges
to the design, construction and operation of the station. With
the station’s close proximity to the homes it is designed to
protect, limitations of the existing sewer network, and
restricted access to the lagoon where construction would occur,
several constraints would complicate construction. Among the
The design of the new
facility could not significantly impact the views from the
Construction would have
to take place in the existing lagoon area, while still keeping
the lagoon (a Category A reservoir under the Reservoirs Act
1975) in continuous service during construction.
Access to the
construction site was routed through a separate strip of land
purchased specifically to minimize the traffic impact on the
nearby housing development.
Construction took place in the existing lagoon area,
while keeping the lagoon in continuous service -
Courtesy of Black & Veatch
‘living roof’ planted with sedum is home to wildlife and
an effective noise baffle - Courtesy of Black & Veatch
Design and equipment
One of the biggest
challenges with selecting equipment for the new SWPS was
maintaining the array of pumps, six out of eight of which will
only be in standby operation at any given time. Archimedes screw
pumps were selected for their reliability and ability to run and
test dry. Pumps were selected at a diameter of 3.8m and length
of 19m - amongst the largest screw pumps installed in Europe.
This equipment choice,
however, affected the design of the facility, which had to be
heightened in order to accommodate the raised lagoon walls and
length of the screws, not to mention the electrical demands and
Environment Agency requirements to keep all critical equipment
above a potential flood level. This presented both visual and
acoustic challenges, which were offset by building fabric
choices, a green roof and additional landscaping.
The equipment choice also
affected the design of the electrical system. Ensuring an
effective start requires a significant spike in power
consumption. This high starting voltage from pumps required a
choice between inverter drives or auto-transformers. The team
chose to design for auto-transformers; however, before
construction had started, new restrictions were placed on
auto-transformer power specifications, significantly narrowing
the window for electrical modelling.
The project faced other
logistical challenges during the design phase, especially when
it came to integrating five different models from five separate
teams. A collaborative approach was adopted using BS 11000-1
The design team built a
single AutoCad Revit 3D model space that incorporated the screw
pump models by Spaans Babcock.
building design by AEW Architects.
Models of the
superstructure steel frame, suspended floors and precast
supports to the living roof from GHD Livigunn.
The reinforced concrete
substructure model developed by Black & Veatch.
The temporary works sheet
for the piled cofferdam by MGF.
All five main models,
along with other supplier details, were brought together to
ensure adequate space within the building for operation and
maintenance. The model was utilised at operational safety
workshops to fully assess issues ranging from access to maintain
each item, to emergency safety escape routes and prevention of
ventilation ductwork clashes with the overhead crane.
The reinforced concrete
substructure model allowed the structural design team to use
Teckla, a 3D rebar design package which reduced the design time.
In addition to the above models, the Black & Veatch hydraulic
designers used computational fluid dynamics (CFD) modelling to
ensure the flow presentation was even and discharge velocities
to the River Hull were acceptable.
The CFD simulations
identified the north and south sewer velocities, suggesting the
addition of baffling to improve the flow presentation of screws.
The result is a more even flow of water to the screws during
principal challenge was the station’s close proximity to
the homes it protects
Courtesy of Black & Veatch
Additionally, an acoustic
model was developed to ensure that the noise levels of the new
pumping station did not exceed those of the previous asset.
Particular attention was paid to the ventilation louvre design
to limit noise emissions from the building.
Finally, the solution had
to address a challenging foundation design. The 8m deep
structure required weight for anti-flotation. The motor hall
required piles for support over the soft organic clay alluvium.
The screw pumps are mounted between the two and could not suffer
differential movement. An innovative cantilever design was used
to avoid expansion joints within the pump channels.
The cantilever system
allowed the expansion joint to be placed at the interface
between the structure and the building, alleviating this problem
and avoiding differential settlement.
While most construction
challenges were identified and addressed during the design
phase, it is worth calling out a few important considerations
and developments that had the potential for impacting project
Risk mitigation was an
important consideration during construction, leading to the
offsite manufacture of the screw pump liners, pre-cast concrete
elements (including floor and living roof panels), and
installation of cables and containment prior to completing the
The sight design
constraints significantly narrowed construction capacity. With
only enough room for one crane, for example, weather conditions
like high winds had an impact on the relatively linear
construction schedule. Excavations for the cofferdam had to
consider base heave from confined artesian water pressure in the
underlying chalk aquifer. With a design floor more than six
meters below sea level, the upward pressures were significant.
motor hall required piles for support over the soft
organic clay alluvium
Courtesy of Black & Veatch
A key constraint was the
limited space for the construction, offloading and storage of
materials. To create more space, project designers moved the
pump station footprint away from the site boundary and construct
the facility within the existing lagoon. Construction of the
pumping station within the existing earth and sheet piled lagoon
wall meant the temporary works cofferdam could tie up with the
existing walls ensuring integrity throughout construction.
It is important to
reiterate that the access to and operation of the existing
infrastructure had to be maintained throughout construction. The
Yorkshire Water operations staff had to be able to safely access
and operate the existing station while the new facility was
being built. This included maintaining enough capacity in the
lagoon to support storm flow operations and construction
the impact on the residents in the immediate vicinity was
mitigated through careful traffic management plans. Part of an
adjacent cinema car park was used for all site personnel
vehicles, allowing safe pedestrian access to the site. A strip
of land in front to the lagoon was purchased to create an access
road for delivery vehicles and construction traffic, avoiding
use of roads on the housing estate.
operations and recognition
The project was designed
around BREEAM environmental guidelines, and the team worked
closely with the local community throughout the process with
regular consultation meetings and frequent letter drops.
Yorkshire Water visited local schools in October 2014 as part of
their outreach programme to talk about the water cycle and flood
The consultations led to
specific design choices, including a brick finish sympathetic to
the local houses, the ‘living roof’ planted with sedum (home to
wildlife as well as effective noise baffling) and solar
photovoltaic panels to generate power.
The new pumping station
became operational in July and was officially opened in December
2016 by Hull North MP Diana Johnson. The new station has around
four times greater capacity and the blue whale-sized pump screws
can transfer the equivalent of an Olympic swimming pool’s worth
of stormwater into the lagoon in less than two minutes. Once
stored in the lagoon, water is then slowly released into the
In a statement at the
time of the official opening, Yorkshire Water’s Director of
Asset Management Nevil Muncaster said:
“The city of Hull was
developed around the opportunities provided by the water
environment, the challenge now is to make Hull even more flood
resilient whilst rediscovering the positive role that water can
play in shaping a successful and sustainable city. Working
closely with Hull City Council, the Environment Agency, East
Riding of Yorkshire Council and other key stakeholders we are
committed to playing our part in helping to deliver that
Local customers were also
given a tour around the new pumping station once completed.
Their initial concerns about the new pump station being close to
houses have been turned to positive feedback citing that moving
the pump station further into the lagoon and including the green
roof softened the appearance, making it less imposing than the
previous pump station.
Consultations led to a brick finish sympathetic to the
local houses - Courtesy of Black & Veatch
The station was delivered
as part of Yorkshire Waters’ AMP5 Framework at a cost of £16m.
Construction began in 2014 and was completed in 2016. Yorkshire
Water employed Black & Veatch as principal designer and
principle contractor, with Arup providing technical consultancy
and site supervision services throughout the design and
construction. Turner and Townsend provided cost consultancy
Black & Veatch earned the
prestigious 2016 Contractor of the Year from the Civil
Engineering Contractors Association (CECA) for its engineering,
procurement and construction work on the station.
The project was
recognized by the Institution of Civil Engineers with a
Certificate of Commendation in March, and with an RICS
Infrastructure award in May.
and publishers would like to thank Rob Moffat, Regional
Engineering Manager with Black & Veatch, Pete McCann,
Project Manager with Black & Veatch, and Jonathan Pearson,
Engineering Manager with Black & Veatch, for providing the
above article for publication.