delivering small value schemes to acute wastewater compliance
by Helen Frost
made permanent - Courtesy of MMB
MacDonald Bentley (MMB) has been delivering the Wastewater Minor
Works sub-programme for the Northumbrian Water Group (NWG) since
2006 with the number of schemes delivered annually increasing
year-on-year. The team must deliver schemes for less than
£150,000, and are targeted at maintaining wastewater compliance.
The projects are batched where practicable, and estimated
efficiencies in excess of £1,000,000 have been achieved by the
team across the programme to date, with the focus being on
delivering ‘outcome-based’ solutions to acute wastewater
problems. The programme utilises an agile, fast moving,
collaborative ‘can do’ approach with the objective of delivering
solutions to operational problems.
The sub-programme schemes
are categorised as ‘Planned’ or ‘Emerging High Risk’.
Approximately 25% of the sub-programme workload is ‘emerging’
schemes, the remaining 75% is ‘planned’ schemes. ‘Emerging’
schemes are generally the result of treatment process triggers
or the treatment works being required to operate in conditions
outside the original design. Solutions often comprise of the
installation of temporary treatment plants, or modifications to
the existing process.
Solutions for wastewater
compliance risks are very diverse and this is reflected in the
scale and variety of the ‘planned’ schemes. The content of the
‘planned’ programme is developed using a survey process
undertaken by both MMB and Interserve. Survey site visits with
NWG Operations are undertaken to review the problems, identify
potential solutions, understand buildability and develop budget
costs before being peer reviewed jointly by NWG Operations and
Asset Delivery. The process ensures that the work scope is fixed
when the contract is awarded, ensuring lean design and reducing
contract costs. The true collaborative approach is shown here
when Interserve use surveys carried out by MMB to deliver
projects, and vice versa. This forms the template for future
working as it demonstrates collaboration through high levels of
trust, consistency and cooperation between the design teams,
construction teams and client project team.
View of Warden STW under construction
Courtesy of MMB
Ecologically sensitive location of the works
Courtesy of MMB
The drive for capital
efficiency, as well as following a sustainable approach, has
encouraged the reuse of existing assets including those stripped
out of other sites, or free issue equipment to ensure that NWG
gain the best value from their equipment during its lifetime.
For example assets were reused at Sherburn STW where continued
compliance was maintained through phased installation of
multiple temporary treatment units, and the reconfiguration at
Brasside STW allowed old and new equipment to run in parallel,
removing significant temporary works risk and costs.
The ‘Emerging Schemes’
programme requires the MMB and NWG joint team to work together
to react quickly to newly-identified issues. A protocol was
developed for such circumstances, allowing teams on emerging
projects to be quickly assembled. In turn, works can be
delivered rapidly, but in a safe and controlled manner within
the required timescales to respond to consent-related changes.
These were reduced from around 10 days to 3-4 days.
The designs are delivered
by a small team with civil, mechanical/electrical and process
specialists, ensuring that everyone can work to their individual
strengths. The nature of the works is such that previous designs
can often be re-used and developed, whilst building in ‘lessons
learned’ in an efficient and cost effective way. In the event of
compliance triggers, MMB, NWG and the supply chain work together
to react quickly to maintain compliance. The involvement of
suppliers negates any abortive works and drives efficiencies and
best value through a true ‘One Team’ approach. The developed
protocol ensures adherence to MMB’s Operational Safety Standards
and NWG operational procedures as well as ensuring the projects
are delivered right first time.
Case Study: Warden STW -
Warden Outfall presented
a number of ecological challenges to the project team. A
significant amount of pre-start work was undertaken to ensure
adequate protection measures were addressed in design, and
implemented during construction to ensure minimal environmental
impact. Examples of the challenges overcome by the team include:
Freshwater pearl mussels
Freshwater fish spawning
Natural England consents
Environment Agency consents
Measures: MMB operate in line with our ISO 14001 environmental
management certification in order to protect and enhance the
environment in the delivery of our services. The ecological
sensitivities associated with this site demanded that the
strictest management controls were adopted on site. The
challenges that the team faced on site included:
Evident on the river bank and required monitoring during all
works on the bank. Foliage was stripped from the bank and
retained close by to avoid any cross-contamination. The same
procedure was implemented for the reinstatement of topsoil once
the headwall was completed. Plant and machinery was cleaned
before tracking on the field after working on the bank, and
operatives’ footwear was also cleaned on exiting the bank.
► Freshwater pearl
mussels, water voles and newts: A survey was carried out
prior to the commencement of works, with any freshwater pearl
mussels found moved by specialists prior to starting work.
► River Tyne
pollution protection: The design adopted a precast
solution to avoid wet concrete near the watercourse. The precast
solution meant that off-site manufacture reduced embodied
carbon, providing a more sustainable approach as well as
reducing the ecological impacts on site through the construction
methods. Flood defence consents were agreed with the Environment
Agency, and straw bales placed to prevent silt run off into the
river. A sandbag cofferdam was also utlised in the river
adjacent to the works, with water pumped out and passed through
a fine silt filter before being allowed to discharge back into
the river. Strict limitations and controls were placed on plant
► Natural England:
Following consultations and with consents in place, any clean
water clams found were to be moved / relocated ahead of the
► Local Environment:
Access to Warden STW was through the sensitive hamlet of Low
Warden via a private ‘no through road’ gravel access track of
200-300m in length. There was no other means of access.
Residents were concerned
that our plant would leave the road damaged following the works,
especially as they had upgraded the track at great expense to
themselves the year before. With this in mind, our team worked
tirelessly to ensure the access track did not get damaged by:
Containing any debris and
mud which could otherwise have spread onto the road.
Only taking plant in once
and not changing it.
Arranging deliveries at
certain times so as not to inconvenience the residents.
Not parking on their road
or blocking access.
View of the
new outfall - Courtesy of MMB
While the project was not
the largest or most expensive we have or will deliver, it did
present a number of logistical and environmental challenges.
Diligent third party engagement was critical on this small but
highly important scheme. Local residents were justified in their
concerns prior to the project commencing because of the
potential for disruption. The project team eased these concerns
through careful stakeholder engagement and working as a
sympathetic and conscientious unit. The team understood the
potential environmental challenges and impacts presented by the
scheme and overcame them by collaborating in order to arrive at
robust mitigation strategies. The team promised the residents
that disruption and noise would be minimised, and delivered what
was promised. The strap line of the project was ‘we did exactly
what we said we were going to do’.
The scheme was completed
to programme and budget whilst enhancing NWG’s reputation within
the local area. This was externally validated by a letter of
praise from a local resident, making reference to how the
ecological challenges have been addressed by the project team.
This approach can only serve to enhance NWG’s reputation in
their protection of the environment.
construction works - Courtesy of MMB
Key to the success of the
Wastewater Minor Works Sub-Programme has been the collaborative
team planning approach adopted by all stakeholders. This has
been driven by constant learning carried forward by the
consistent team deployed on the work. By working together in a
‘one-team’ approach NWG, MMB and Interserve are ensuring
continued wastewater compliance using innovative solutions and
flexible procurement methods, built on the foundations of
effective project delivery. Collaborative working is at the
heart of the wastewater Minor Works Sub-Programme, with team
members working in a co-located environment. The maturity of
this relationship has allowed open challenge to arrive at
outcomes best suited to the needs of NWG. Collaborative ‘Peer
Reviews’ with NWG Operations and Asset Delivery are undertaken
following survey of candidate assets as described in the
‘planned projects’ section.
relationships have been developed within the wider NWG
community. This has helped to provide rapid and agile responses
to acute issues, protecting NWG assets and reputation, and the
environment. We have challenged existing ways of working to
arrive at the most effective delivery mechanism and have
utilised ‘lean’ planning techniques such as ‘Plan to Protect’
and the ‘3 Levels of Planning’ to deliver efficiencies, whilst
providing a rapid response to serious compliance and flow
The collaborative core
team process has resulted in the wider community and other
stakeholders being brought into the process at an earlier stage.
This ensured a full understanding of the risks involved, better
time management and reduction of waste through the life-cycle of
the project. The variety and nature of the work takes us into
the wider community, many times into small villages were there
is a high likelihood of noise and disruption for NWG customers.
Whenever possible, MMB and NWG work to deliver a lasting legacy
for the local residents with a view to enhancing NWG’s
reputation among its customers.
and publishers would like to thank Helen Frost, Lead
Designer with MMB, Ben Gilbert, Project Manager, and Jonny
Belmont, Project Manager, both with Northumbrian Water
Group, for providing the above article for publication.