Page 36 - Gi flipbook September 2018

IGEM NEWS | Young Persons Paper Competition 2018

MOTHER NATURE DOESN’T

SIGN EASEMENTS

By Matthew Goode, Network Supervisor O&M Projects at Cadent,
Young Persons Paper Competition 2018 first runner-up

hen faced with
serious river bank
erosion that
threatens the
integrity of an asset,
Wyou have to
intervene, either by removing the
asset or removing the threat.
Threatening the supply of 250,000
properties in the Manchester area is
the River Mersey. The flowing river is
clawing away at the bank, which
houses the Partington-to-Stockport
18in steel gas main, operating at 32bar
on the boundary between Stockport
and Manchester councils.
As a gas engineering company, facing
an environmental engineering problem
is not our everyday business. With
guidance from specialist contractors, I
decided to divert the River Mersey
back to its 1967 channel to protect the
pipeline, utilising soft engineering
techniques to ensure that it stays there
for the foreseeable future.
In conjunction with Northern Divers
and Cain Bioengineering, I am re-
commissioning this channel on the
inside bend and rebuilding the outside The River Mersey
bank. Following a topographical survey
of the river, our bioengineering gradually getting closer to the river the boundary between Stockport
consultants have created an all- edge. On closer inspection, it was Council and Manchester Council.
inclusive solution to protect our assets, identified that the river’s course was In order to prevent further erosion
preventing erosion from simply moving changing and eroding at an alarming and take proactive protection of the
up or downstream. The designs include rate, therefore reducing the amount of pipeline, I have contracted Northern
shallower river banks, an attenuation protection for our asset. Divers to act as main works
riffle and stabilised banks. The project The Partington-to-Stockport pipeline contractor, including principal
started in spring 2018 and is due for was laid in 1967. At this time, the river contractor and principal designer
completion this autumn. was approximately 30m away from under Construction (Design &
the pipeline, not imposing a risk. At Management) Regulations (CDM).
BACKGROUND the time of writing, there is less than Due to the complexity of the works
Cadent owns and operates over 5m of bank between the river and and the nature of this river, Northern
131,000km of gas mains within its four pipe, which is getting smaller and Divers has brought in the help of Cain
networks, delivering gas safely and smaller every day. Bioengineering, which has over 40
securely to approximately 11 million Figure 2 shows an overview of the years of experience in river works,
customers. Our high pressure area. The Cadent pipeline is laid hydrology and fluvial dynamics.
pipelines are regularly monitored via amongst other physical and
aerial and local methods to ensure stakeholder challenges such as THE PROBLEM
that our easements are being adhered National Grid pylons, the Waterside The River Mersey and its tributaries
to and that Mother Nature is not Hotel and Network Rail assets. Just have a huge catchment area,
encroaching on our assets. upstream is the start of the River extending east of Manchester and to
During cyclical inspection, our Mersey, which is the confluence of the Peak District. In order to ascertain
pipeline inspectors noticed that the two rivers – the Tame and the Goyt. an understanding of the extent of the
Partington-to-Stockport pipeline was Historically, the river was chosen as erosion, remediation works and costs,

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