12/05/2005 - The Environment
Agency has announced on 11 May 2005 that planning
permission has been granted for our new £4.5
million flood alleviation scheme for the Ridings
Brook in Cannock.
The application was submitted to Cannock Chase
Council on 16 February 2005.
Our Project Manager, Roger Prestwood, says:
"This is great news. The granting of
planning permission for our proposal means
that we can now start building the scheme
to protect up to 88 homes and 54 businesses
from the misery of flooding."
The scheme will be built in two phases to
minimise disruption and inconvenience to the
town:
Phase 1( starts summer 2005 )
The dam at Mill Green Balancing Pond will
be raised by 1.9 metres, providing additional
storage to give increased flood protection
to all properties within the Ridings Brook
floodplain. An automated control structure
will house equipment to control water levels.
Improvements, such as a small visitor centre,
additional trees and landscaping to encourage
wildlife, are included in the plans. They
will include refuges to protect the vole population
and cattle during high water levels.
A new flood-relief channel and culvert will
be built under the A5 trunk road to assist
in clearing water away from this area during
a flood. There will be some disruption to
traffic during construction, but this will
be kept to a minimum and public information
will be made available before work starts,
clearly outlining alternative traffic routes.
Phase 2 (starts spring 2006)
An 80 metre long flood wall about 1-1.5 metres
high will be built along the rear of properties
on the north side of Rumer Hill Road. New
walls each side of the brook upstream of Rumer
Hill Road will protect properties on both
sides from flooding. Further walls, 100 metres
long, on both sides of the brook south of
Rumer Hill Road will protect more properties.
Gardens and other areas affected by the scheme
will be landscaped on completion.
Notes:
An electronic copy of a diagram (in colour)
showing the location of the proposed works
is available by e-mail from the above number.
You are welcome to reproduce it.
Ridings Brook
The Ridings Brook drains an area of land
that includes parts of Cannock Chase, Hednesford
and eastern Cannock. he brook generally flows
in a south-westerly direction from Pye Green,
just south of high ground in Cannock Chase,
south through the urban areas of eastern Cannock
and Bridgetown. It joins Saredon Brook, south
of the A5 trunk road, before joining the River
Penk. The brook is only 6.2km long and drains
an area of 18 sq km, the majority of which
is urban. The brook’s tributaries include
Pye Green Brook, County Brook, Hawkes Green
Brook and Golly Brook North.
Flooding in Cannock
Cannock has a history of flooding from the
brook in recent years, with notable events
occurring in September 1994, July 1999 and
November 2000. The current standard of flood
protection to properties within the Ridings
Brook floodplain is largely inadequate, with
some areas beginning to flood in a 1 in 5
year event (a flood with a 20% chance of happening
in any one year).
The existing flood defences depend on a storage
reservoir known as Mill Green Balancing Pond,
within the Mill Green Nature Park, which offers
a degree of protection. In 1977 an existing
pond was enlarged and modified to operate
as a balancing lake, retaining water using
manually controlled sluices set in an earth
dam. However, once the pond is full the water
flows over the top, flooding properties downstream.
South of Mill Green Balancing Pond the Ridings
Brook runs through a number of undersized
culverts (underground channels). As a result,
some areas around these culverts are also
very susceptible to flooding.
The 1994 flood was the result of severe multiple
storms. The Mill Green Balancing Pond did
not have sufficient time to drain down between
the storms and water overtopped the dam, causing
flooding downstream. Many areas of Cannock,
including Rumer Hill Road, Walsall Road (A34)
and Watling Street (A5) were all severely
affected. The A5 was closed for two days.
After the 2000 floods, the Mill Green Balancing
Pond was de-silted and enlarged but computer
modelling shows that the storage capacity
is still below the required level. Studies
have shown that the pond has a 10% chance
of overflowing in any single year.
In October 2003 a new river gauge was installed,
which allows improved flood warnings to be
given to residents and businesses. This gives
people time to prepare and to reduce the effects
of any flood.
We are now proposing to provide an effective
flood alleviation scheme to improve the standard
of flood protection from the Ridings Brook
for all properties that lie within the floodplain
downstream of Mill Green. Under these proposals,
the most vulnerable properties will not begin
to flood until a 1 in 50 year event (2% chance
of happening in any one year), with most properties
protected against a 1 in 100 year event (1%
chance of happening in any one year).