WWII Pillbox Conversion -
Background & History
pillboxes in Kings Worthy and Headbourne Worthy are concentrated to the
north of the area surrounding the army camp at Worthy Down. During
WWII this former RAF base (RAF Worthy Down) - built on the
site of the old Winchester Racecourse - was handed over to the Royal
Navy and became HMS Kestrel occupied by Fleet Fighter Squadrons 800
and 803. In order to defend the camp from enemy attacks, and avoid
the airfield’s capture, a blockade of defenses was erected circa 1940,
including a perimeter of pillboxes. Mostly Type 22, there are
upwards of 30 pillboxes, situated in open fields, hidden amongst
scrub in hedgerows and woods, semi-buried in the ground, a few in private gardens, and one even built around an oak tree
(unfortunately now just a dead trunk!).
Since the war many pillboxes have
been abandoned of no practical use in modern times. An attempt
was made to blow up one ‘inconveniently' placed, but this failed still clearly intact visible from Hook Pit Farm Lane. Most
are concrete appearance; however a few have
an outer brick-shell.
Three pillboxes are accessible from Hook Pit Farm Lane; one on
the lane itself (full of rubble) and two others (one brick) on the old
DNS Railway line now a public footpath.
The pillbox identified for conversion is the southernmost of the two on the DNSR
footpath, Grid ref
SU 480 342,
of concrete construction.
This section of the old DNS Railway line
from Kings Worthy to South Wonston is owned by Hampshire County
Council (HCC) Estates, from whom permission for the work has been
granted. Worthys History Group having an interest in such historical
artefacts has also been advised – indeed Worthys Conservation
Volunteers had brought these WWII structures to the notice of Worthys
An opportunity by
Worthys Conservation Volunteers to make use of an otherwise abandoned
structure was identified. And on discovering on the Internet that
pillboxes elsewhere in the country had also been converted, members of
the group set about researching into and campaigning for their
habitats for bats, culminating in the following scheme of work.
An added benefit of the
scheme is the implicit protection in perpetuity of at least one of the
pill-boxes. It is the intention that any structural alteration shall
be absolutely minimal, and that all works be reversible should the
project prove unsuccessful. Of course, once bats take up residence
- which probably might take a few years - the
roost is legally protected from all interference.
As well as HCC and
Worthys History Group, support for the project has been given by a local
bat conservationist who made a visit to the site in Spring 2010.
In masterminding the
conversion certain criteria have been considered:
Must be cool and damp –
bats need fairly constant atmosphere that is cool and damp, and rely on
high-levels of humidity, so best if waterlogged at bottom. The lower
level entrance could act as a suitable sump for collecting water
therein providing a means of maintaining dampness within the structure
to provide a suitable roosting environment
Create suitable nooks
and crannies – can be created between breeze blocks, using ventilation
bricks. Regular bat boxes probably offer the best option for
Access from the side
entrance is best – block all gun ports and leaving the entrance partly
open for access by the bats. Discourage access from the passer-by by
limiting the size of the entrance although inspections will need to be
The work will therefore
1. Blocking all
the gun-holes (aka loopholes) with breeze blocks, fixed from the inside
using a cement mortar. Lightweight concrete blocks will be used having
a much firmer constitution than although somewhat heavier. A double
skin of breeze blocks may be considered providing bats additional nooks
or resting place between skins
This will have no real visual impact and is
to be done so that no structural changes are made at all. It would be
possible to knock out the breeze at any time in the future should it be
2. Securing ready-made bat-boxes to
the "Y" AR wall and also some onto the inner surface of the structure.
Any screw holes to be sited along mortar lines or in pre-existing screw
holes if at all possible, so as to minimize structural damage
It has been noted that
other conversion projects have used ‘holed’ bricks of varying types,
however bat-boxes are considered the better option.
entrance, again with lightweight concrete breeze blocks, providing a
suitable entrance-hole for the bats. This is to deter children, dogs,
etc, entering, and also to protect the bats from interference. As
inspections will need to be carried out every so often, access shall
not be completely restricted but just made very difficult. (Only
licensed bat handlers will access the structure only once bats have
Alternatively, a strong wooden frame
mounted from inside and then a ‘door’ of double marine-ply or
similar bolted with tamper-proof or key-operated bolts or screws from
the outside would seem to fit the bill.
4. Maintaining dampness within the
structure by piping runoff rain-water into the entrance.
5. Erecting an information board may
be carried out – although this may encourage the wrong type of
Monitor the presence of
bats using suitable bat detectors.
The plan is to carry
out the work over two tasks:
September 2010 - Block
all gun-holes and fix bat boxes to walls
For blocking the gun-holes: 12 light-weight
concrete blocks, cement, sand and water;
For the bat-boxes: ready-made bat boxes,
Wheelbarrow, spade, trowel, bolster,
lump-hammer, cordless hammer-drill, torches.
October 2010 - Build
Materials & equipment:
To be confirmed.