David Villis has been the South Gloucestershire
Ecologist since 2001 and sits on the Avon RIGS committee. I asked him to tell
me a little bit about himself and his involvement in geoconservation in the
Avon region.
Hi David. I wonder if you could
briefly explain what being the South Gloucestershire Ecologist involves on a
day-to-day basis?
I am part of the
Strategic Planning Policy and Specialist Advice Team for South Gloucestershire Council. I work with landscape officers, archaeologists and conservation
officers and, whilst there to give advice to other
Council departments and the public, my primary role is to provide comments to the Development Control and Major
Sites teams on planning applications. These range
from to new power stations to house extensions.
How did you come to be in your
current job?
In terms of
academic background, I studied Applied Biology at Hatfield Polytechnic.
Immediately after I graduated I managed a record shop for four years, which was
great fun!
I started work with the Nature
Conservancy Council (subsequently English Nature and Natural England) in the
80s and in 1991 took up the position of Protected Species Officer, working predominantly with bats, badgers, great-crested newts and dormice.
It was through this role that I gained an insight into the planning process and
that led me to applying for my current job.
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A hibernating dormouse. Protected Species Officers look after the interests of dormice and similarly legally protected species in the UK. Photo credit: John Robinson/Natural England. |
Considering
your biological background and ecological job title, how does geology fit into
your role?
When a planning
application comes in, the first thing we do is locate the proposed development
on our GIS database. If an area has previously been recorded as having
geological importance, such as a SSSI or RIGS, this will be flagged up and
taken into account throughout the application. A lot of planning proposals have low geological
impact; landfill and quarry expansions/restorations are generally the most significant issue that we have
to consider with regard to RIGS.
You mentioned
RIGS and SSSIs – what exactly is the difference between the two?
They are part of
the hierarchy of how natural heritage, specifically geology, is defined and
preserved. At one end of the scale you have outcrops that are internationally
important and are UNESCO World Heritage Sites, such as the Jurassic Coast.
Geological SSSIs (Sites of Special Scientific Interest) are considered to be
nationally important and can comprise either exposures or deposits; a good
local example is Burrington Coombe in the Mendips. The next step down from
SSSIs are Local Sites. RIGS (Regionally Important Geological and
geomorphological Sites) fall under this umbrella. They represent outcrops that
have regionally significant scientific and educational value.
In terms of
legal protection, what does the designation of a RIGS actually mean for an
outcrop?
A RIGS is a
non-statutory designation.
This means that the site doesn’t have any legal
standing but is protected from development under the South Gloucestershire Local Plan. Policy L8 of the Plan does not permit development that would cause damage to a RIGS unless
the importance of the development is considered to outweigh the value of the
affected RIGS, in which case measures will be taken to minimise and offset the
impact on the outcrop. As a local authority, we have no influence over the
management of RIGS although we of course encourage all landowners to manage them sympathetically.
How does a
site in the Avon region become a RIGS?
Technically outcrops
can be put forward for designation by anybody, although in reality nearly all are proposed by the Avon RIGS Group.
Members of the RIGS Group evaluate any putative
site against the criteria for designation and then present it to the Local
Sites Partnership (of which the Avon RIGS Group are a member body) for official
approval. Their recommendation is then taken
by myself and presented to the Executive Member for the Environment for South
Gloucestershire Council and, if approved, the information is sent to
BRERC
(Bristol Regional Environmental Records Centre) for digitisation
and inclusion on the GIS database.
Have you been
involved in any cases where the geology has significantly impacted on a
planning proposal?
A recent success
story for RIGS has been Barnhill Quarry in Chipping Sodbury. The quarry was
operational from the late 19th century until the mid-1960s with the
Carboniferous limestone being exploited for aggregates and building stone.
Extraction of the rock led to the revealing of some magnificent exposures in
the quarry walls, including stromatolites, limestone pavement, ripple bedding,
dolomitic wadi deposits, thrust planes and an well-defined unconformity between
Triassic shales and Carboniferous limestone. Part of the site was assigned SSSI
status in 1966, with subsequent audits awarding RIGS designation to the whole
quarry.
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Exposures at Barnhill Quarry, Chipping Sodbury. Left: Fossil stromatolites in Carboniferous Limestone. Right: Ripple bedding in Lower Cromhall Sandstone. Photo credit: WYG Environment, Barnhill Quarry Geoconservation Assessment |
In 2010, we
received a planning application to partially infill the quarry and build 170
house plus a large supermarket. Obviously the potential development posed a
significant threat to the geology and we had to ensure any construction
activities did not destroy important aspects of the site. For example, if any
exposures would be covered by the infill, we needed to be satisfied that the
characteristics were replicated elsewhere in the quarry wall.
In terms of
implementing changes to the planning application, our approach was threefold.
Firstly, we made provisions for surveying the site before and during
construction activities. Secondly, we incorporated educational features into
the proposed development such as an information hut, interpretation boards and
a geo-trail, as well as improving public access, which is currently forbidden.
Finally, it is essential the outcrops are monitored and maintained, for example
keeping rock faces clear of vegetation.
All this is tied
into a Section 106 agreement; this means that if the proposal goes ahead, the
cost of the conservation measures is met by the developers.
What is your
favourite RIGS?
My favourite
local geological outcrop is Aust Cliff, a cliff exposure about 10km north of
Avonmouth on the Bristol Channel. Not only does it have national significance
with great exposure of the Westbury Bone Bed, the colourful strata are visually
dramatic. It really is a spectacular sight when driving across the Severn
Bridge in the late afternoon with the bedding planes in the rock face
highlighted in the low-lying sun. The site accessibility is superb and it’s a
perfect outcrop for educational and recreational visits.
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Aust Cliff SSSI, north of Avonmouth, is one of the best exposures in the country of uppermost
Triassic and Lower Jurassic rocks. The colourful strata document the transgression of the Jurassic sea over Triassic desert plains. Photo credit: David Villis |
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Charly Stamper