Parish Council Flood Risk Response

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APPLICATION REFERENCE JMATTL/11/00507/FULM
The letter from the Environment Agency enclosed with the report recommends refusal and gives
reasons with which we have a considerable amount of sympathy
Further to the update of the planning application for Brookside Paddock the flood risk assessment
surprise surprise indicates that the new development will not be at risk of floods! The Parish Council
are not concerned about the risk for the new development which is on an uphill site, what we are
concerned about is the increased risk to existing property along the path of the unnamed
watercourse aka "Breedon Brook", and upstream of the application site. The report also mentions a
ditch which runs through the site, there is no mention of the fact that this ditch has been formed by
erosion caused by water flowing from a spring at it's southern end. Following is an excerpt from the
flood risk assessment supplied to us by Centremaps, it is clearly at odds with the assessment carried
out, on behalf of the applicants, by RAB Consultants which on page 10 states and we quote:
“Therefore the proposed development is appropriate for the flood risk and is not expected to increase
the risk of flooding elsewhere" The claim is made that the site is in flood risk Zone 1, but the adjoining
land at the north end of the site is according to Centremaps in flood zone 3 with a VERY HIGH RISK of
flooding. The assessment also claims that the owners have no knowledge of the site flooding in the
recent past, however the applicants the developers the owners and the surveyors are all of the same
family and may not remember all instances of the flooding of which we have photographic evidence.
Mrs Devaney at number 8 Main St also can provide compelling evidence. The letter from the
Environment Agency ref LT/2011/113373/01-L01of 11th August to Mr Mattley states categorically that
"The FRA will need to demonstrate that a residential development on the site is safe and DOES NOT
INCREASE FLOOD RISK TO OTHERS. The letter also states that " The current proposal is concerning
as the road culverts appear to be undersized and would therefore be subject to blockage risk and
exacerbate any flood risk on the site". This is already a problem as blockages regularly occur.
Page 7 para 8.0 of the RAB Consultants report clearly states that "The current site has an
impermeable area of approximately 160.3 m ². The impermeable area of the proposed development will
increase to approximately 2565.5²." This will clearly significantly add to the run off to the Breedon
Brook and will exacerbate the upstream problem of flooding.
RAB also state on page 8 of their report under the heading SOURCE CONTROL and subheading
Soakaways that "According to www.landis.org.uk/soilscapes the subsoil type for this area of the UK is
classified as "slightly acid loamy and clayey soils with impeded drainage" The report also suggests that
one of the techniques that could be employed to limit surface water run off could be rainwater
harvesting ie using saved water for not potable domestic purposes such as "watering gardens, car
washing, flushing toilets and use in washing machines". We suggest that the developer has absolutely
no control over such usage and is clutching at straws in suggesting that it is a possible way of
preventing flooding.
Following are two excerpts from the Centremaps report which we have referred to above.
2. British Geological Survey Groundwater
Flooding
2.1 Groundwater Flooding Susceptibility Areas
Where land that is prone to groundwater flooding has been built on, the effect of a flood can be
costly. Because
groundwater responds slowly compared with rivers, floods can last for weeks or even months.
What is the highest susceptibility to groundwater flooding in the search area based on the underlying
geological conditions? Very High
Guidance:
Where very high susceptibility is indicated, this means that given the geological conditions in the area
groundwater flooding hazard should be considered in all land-use planning decisions. It is
recommended that other relevant
information e.g. records of previous incidence of groundwater flooding, rainfall, property type, and
land drainage information be investigated in order to establish relative, but not absolute, risk of
groundwater flooding.
3. JBA Surface Water (Pluvial) Flood Risk
3.1 JBA Surface Water (Pluvial) Flood Risk
Surface Water (pluvial) flooding is defined as flooding caused by rainfall-generated overland flow
before the runoff enters a watercourse or sewer. In such events, sewerage and drainage systems and
surface watercourses may be entirely overwhelmed.
Surface Water (pluvial) flooding will usually be a result of extreme rainfall events, though may also
occur when lesser amounts of rain falls on land which has low permeability and/or is already
saturated, frozen or developed. In such cases overland flow and 'ponding' in topographical
depressions may occur. The data within this report is based upon a modelled 1 in 200 year rainfall
event, and indicates the depths to which an area may expect to be flooded in such an event.
What is the risk of pluvial flooding at the study site? Moderate
This data is provided by JBA Consulting, © Jeremy Benn Associates Limited 2008/2009
The following pluvial (surface water) flood risk records within 50m of the study site are shown on the
flood map
ID Distance Direction Risk Depth of Flooding (m)
1 10.0 W Low Susceptibility Between 0.1 and 0.3m
12 15.0 N Moderate Susceptibility Between 0.3 and 1m
13 21.0 W Moderate Susceptibility Between 0.3 and 1m
16 30.0 N Significant Susceptibility Greater than 1m
This information was taken from an enquiry to “Centremaps” based on 8 Main St., Breedon on the
Hill. This property includes the north bank of the Breedon Brook and is at very high risk of flooding, in
fact it has been flooded quite recently. Any further surface water run off flowing directly into the
brook will only exacerbate this already serious problem.
This application is nothing more than an opportunist attempt to convert an underutilised asset into
profit for the owner.
There used to be allotments on this site a facility which is in demand from the residents of the village
as there are no others . It would be a good idea to utilise the site for that purpose, it would be popular
and would enhance the facilities available to villagers.
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