Method Statement – Wastewater
The purpose of a model is to assist in understanding the behaviour and performance of a
system being studied. Wastewater network modelling may be undertaken to simulate either
the hydraulic or water quality performance of the wastewater networks within a drainage
catchment.
The value of modelling lies in its ability to identify cost effective solutions, through better
understanding of system behaviour and the impact on customers and on the environment.
Models can range from rapidly constructed default models up to fully verified hydraulic and
water quality models. The models may be used to simulate the performance of the network
under a variety of dry and wet weather conditions and to identify and test the viability of a
number of solutions.
The level of detail and effort expended in data collection and verification of the model should be
appropriate to the scale of the problems and anticipated expenditure in the catchment area.
Typical applications of wastewater network models are shown below.
MWH’s approach
MWH approaches all of its projects from a culture that promotes close team working and
innovation. Team working has consistently proved to be the best approach to reach
stakeholder consensus and acceptance of solutions. Our experience enables us to offer both
broad option and detailed assessment of the whole life cost implications of solutions leading to
identification of the optimum solution with our client.
The team organisation establishes a management and control structure with a breadth of skill
and knowledge that ensures all technical and managerial aspects are fully considered.
Supported by an active global knowledge community, local teams can build on the best of our
globally developed capabilities, to ensure that innovation and lessons learned can be applied
locally.
The wastewater networks group currently comprises over two hundred fully qualified engineers
and technicians, based in twelve offices throughout the UK, who have extensive experience in
all aspects of wastewater network engineering.
The group operates under a matrix
management system whereby work is managed by a number of dedicated specialists –
programme, project and technical managers. This has allowed MWH to develop our staff to
meet the challenges of an expanding programme of work.
MWH has extensive experience in the management and delivery of network optioneering
supported by advanced catchment models. We operate integrated, balanced teams with
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Method Statement – Wastewater
suitable expertise in the fields of modelling, design and construction. It is in the outline
development and optioneering of network solutions that the majority of capital savings can be
identified. This objective, to minimise total solution costs, is at the heart of MWH’s approach.
Management of subcontractors
The group also has extensive experience in the management of sub-contractors for all aspects
of data collection. The input of sub-contractor services is a prerequisite of all wastewater
network modelling projects and has a fundamental effect on the quality of the final product,
along with its final costs and time scale. It is vitally important that data obtained from subcontractors is accurate, acceptable and received on time. MWH operates systems that ensure
delivery and the control of data quality by providing clear lines of communication and
accountability. We also employ software and tools to ensure that data received from
contractors is suitable in terms of completeness, quality and format.
MWH Modelling software
We are recognised industry specialists in software development and data management and
have utilised these skills in developing systems for a number of clients. These systems include:
• Paperless reporting.
• Geographical sewerage asset system.
• Databases.
MWH is an active participant in the development and testing of Wallingford Software’s
programme suite and we have developed a number of modelling software tools, including:
• Modasset Data Manager - a standalone GIS based database product, which allows the
user to manage and view information on networked systems. Modasset DM has been
successfully used on a variety of projects worldwide. The database simplifies asset survey,
data clean up, model build, result analysis and optioneering as well as tracking changes to
the database throughout the project.
• Flow Survey Software - several software programs, including “Flow Survey Viewer” and
“Quality Graph Manager” have been developed to process flow survey data and to produce
comparison plots of both observed and predicted data from hydraulic models.
• Paperless Reporting Software – developed to allow the rapid production of electronic
reports to allow easy access and retrieval. Documentation for a number of UK clients is
now being produced in this way.
• Planning Tool – A GIS interface to the model for assessing the implications of and
restrictions on development within a catchment.
•
RIOT – RIOT (River Impact Optimisation Tool) is able to process/analyse model results
for urban pollution management (UPM) studies and optimises solutions to provide clients with
cost-effective solutions to water quality problems.
Benefits
The principal benefits of MWH’s approach to wastewater network modelling are:
• Value – Network analysis at an appropriate level of detail early on in a project can deliver
significant capital savings for clients.
• Delivery – MWH developed software automates tasks to help deliver large scale modelling
solutions in a fraction of the time of more traditional approaches.
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Method Statement – Wastewater
• Quality – MWH’s organisation ensures that the necessary expertise is applied to each
commission and that technical quality is constantly monitored.
• Efficiency – Automation and the application of appropriate resources, including the use of
MWH’s International Design Centre in India offers a quality service at a lower cost.
• Continuous Improvement – MWH’s ongoing investment in the development of
methodologies and processes has made the company an industry leader in this field
• Consistency - Our development of data management software and structured
methodologies mean that a consistent quality of output is maintained throughout the
company.
Experience
MWH has been at the forefront of wastewater network modelling for clients in the UK and
overseas for over 20 years, including the majority of UK water PLCs. The work undertaken has
been wide ranging, including:
• Drainage area plans.
• Water quality models.
• Macro models; simplified models.
• Rapid default models.
MWH has experience of integrated catchment modelling incorporating sewer, wastewater
treatment works and river catchment models. Models have been used for a range of purposes
from strategic catchment planning to the development of specific solutions, e.g. unsatisfactory
combined sewer overflows and sewer flooding problems.
MWH has assisted a number of clients in developing and implementing their wastewater
network modelling programmes including prioritising study areas, preparing survey contract
documents, generating specifications and developing data storage systems.
Summary
MWH’s wide ranging skills, combined with a clear understanding of our clients’ needs, ensures
that we can produce network modelling solutions within a short time scale. These solutions
combine innovative approaches with technical excellence to provide best value long term
solutions.
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