BLETCHLEY PARK - Milton Keynes Council

BLETCHLEY PARK
CONSERVATION MANAGEMENT PLAN
FEILDEN + MAWSON
for
EDAW
Draft 06 after public comment
25 th May 05
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Conservation is the management of change, in a sustainable
manner, so as to pass on cultural value to future generations.
Definition agreed at EH GHEU seminar on Conservation Management Plans, Bicester 29 Oct 2004.
A Conservation Plan is a live document, based upon consensus, which should be reviewed and
updated periodically. An initial review after 1 year is proposed, followed by a 3 year cycle, in the
future.
SUMMARY
Bletchley Park has an interesting if unexceptional history up until the point at which it was chosen to be the out of London
base for the Government Code and Cipher School in 1939 at the start of World War II. Its function and scale of activity
were not generally known until 1974, and its effect on the progress and outcome of WWII is still being discussed and
assessed, but is generally agreed to be of national significance and arguably of international significance, although
because of the nature of its work direct comparisons with similar organisations abroad are almost impossible.
The achievements at Bletchley Park were primarily intellectual, organisational and technical. The buildings that we see
today were containers for this activity, and although sometimes specifically adapted or developed to enable that activity
would be of little consequence in isolation.
Within the period of WWII there are distinct phases of development, and it is the expression in built form of the changes
in process and scale that give what is left of Bletchley Park its cultural and historical significance today.
The post war period has its own interest, and is paradoxically less well understood, but has left less physical relic (apart
from temporary structures and the NavAid school), having generally reused the WWII structures.
After the end of the Cold War, the site was effectively abandoned by Government Agencies, and many of the buildings
have remained empty and derelict ever since.
The Bletchley Park Trust was founded in 1992 to rescue and promote the site, drawing together the various voluntary
and adventitious uses. They have a vision of enhancing both the physical stimulus on site and the intellectual
achievements. The full extent of the WWII site is no longer available, and even so it is unlikely that BPT will ever have
the resources to encompass all of the remaining site, and that they will concentrate their activity in the central core area
around the Mansion.
This leaves the future of the larger blocks, C, D, G and H, in doubt. These blocks are currently empty and partially
derelict, except for Block H which houses the project to recreate Colossus. The conclusion reached is that without
financial input these buildings have no short term future, and without beneficial use they have no long term future, and
are a liability. This does not mean that they should be demolished, but rather that phased and increasingly substantial
intervention will be necessary in the short to medium term unless beneficial use can be found.
Whatever happens to the buildings, they and their significance are difficult to understand in one visit. A modern
professional scheme of display and explanation, and improved site signage and wayfinding, are necessary to realise the
full Heritage potential of the site.
This Management Plan will inform a Masterplan for the site prepared by EDAW, which address these issues.
INSTRUCTIONS
English Partnerships, working with Milton Keynes Council and English Heritage, instructed EDAW to prepare a
Masterplan for Bletchley Park as part of a wider exercise looking into the future of Milton Keynes and its
surrounding area.
EDAW appointed Feilden and Mawson to prepare a Conservation Management Plan to inform their Masterplan,
building on the research work recently carried out by English Heritage and others.
Other members of the master planning team include Metaphor, Gardiner Theobald, Alan Baxter Associates, and
DTZ
AKNOWLEDGEMENTS
Bletchley Park Trust Christine Large
English Heritage Graham Steaggles, Jeremy Lake, Linda Monckton
Brian Giggins County Archaeologist
Tracy Coleman MKC Conservation Officer
Sir John Keegan
AUTHOR: Hugh Feilden MA(Cantab) Dip Arch RIBA MAPM
Feilden and Mawson LLP
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CONTENTS
INTRODUCTION
SITE HISTORY
SITE DEVELOPMENT PRE 1938
SITE DEVELOPMENT 1938 – 1945
SITE DEVELOPMENT 1945 – 1993
SITE DEVELOPMENT 1993 – 2004
THE KEY PERIOD WWII
EQUIVALENT SITES AND ORGANISATIONS
THE WIDER CONTEXT IN BRITAIN
EH ASSESSMENT OF VALUES
GENERAL STATEMENT OF SENSITIVITY AND VULNERABILITY
LEVELS OF INTERVENTION
COMPARATIVE COSTINGS
COST MATRIX
GENERAL PRINCIPLES
SITE SPECIFIC POLICIES
APPENDICES:
GENERAL MAP REGRESSION WITH AERIAL PHOTOGRAPHS
BUILDINGS GAZETTEER
LISTING DESCRIPTIONS
MKC CONSERVATION AREA DESCRIPTION
MKC PROPOSAL FOR A MANAGEMENT GROUP
LIST OF DRAWINGS HELD BY BPT
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INTRODUCTION
Approach
Our approach follows ICOMOS guidelines:
read a monument, ensemble or site and identify its emotional cultural use and significance
understand the history and technology of monuments, ensembles or sites in order to define their
identity, plan for their conservation and interpret results of this research.
Understand the setting of a monument, ensemble or site, their contents and surroundings in relation
to other buildings gardens or landscapes.
Find and absorb all available sources of information relevant to a monument ensemble or site being
studied.
Understand and analyse the behaviour of monuments ensembles or sites as complex systems.
Diagnose intrinsic and extrinsic causes of decay as a basis for appropriate action.
Inspect and make reports intelligible to non specialist readers of monuments, ensembles and sites,
illustrated by graphic means such as sketches and photographs.
Know understand and apply UNESCO conventions and recommendations and ICOMOS and other
recognised Charters regulations and guidelines.
Make balanced judgements based on shared ethical principles and accept responsibility for the long
term welfare of cultural heritage.
Recognise when advice should be sought and define areas of need of study by different specialists,
eg wall paintings, sculpture and objects of artistic and historic value and/or studies of materials and
systems
Give expert advice on maintenance strategies management policies and their policy framework for
environmental protection and preservation of monuments and their contents, and sites.
Document works executed and make the same accessible
Work in multidisciplinary groups using sound methods
Be able to work with inhabitants, administrators and planners to resolve conflicts and develop
conservation strategies appropriate to local needs, abilities and resources.
Methodology
The methodology follows that developed by James Semple Kerr for the production of Conservation Plans.
Understanding the Place
Establishing the history of the site and the extent of information currently available about its architecture,
fabric and people and events with a strong association with the site. The detailed research work carried out
by English Heritage building on earlier work by David Evans, Fleur Hutchins and others fulfils this part of the
methodology, and, subject to comment received when it is made publicly available, is as comprehensive as
can be achieved on present information.
Following the recent research effort by English Heritage and release of documents by GCHQ it is probable
that in general terms what can be known at present about the history of the building fabric is known, and
that there is sufficient knowledge to make strategic decisions.
Sensitivity Analysis
Showing in a graphical format the relative sensitivity of all parts of the site, usually in five gradations,
together with a written explanation of the differences between the gradations.
Discussion of the sensitivity analysis with interested parties and authorities, ideally resulting in an agreed
analysis, but if not highlighting and if possible explaining differences of opinion.
Jeremy Lake’s values paper for English Heritage identifies the significant activities and associations during
WWII. The building gazetteer records these in an abbreviated format together with analysis based on
PPG15 categories to give general sensitivity analysis. Detailed analysis has been started for major buildings such as
Block D based upon measured survey drawings, and when completed will inform future editions of the Conservation
Management Plan.
The importance of the site and the key values associated with its historic fabric largely relate to its use and development
between 1939 and 1945 during WWII. The key values identified by English Heritage are:
The development of signals intelligence SIGINT
The processing and analysis of signals intelligence DATA PROCESSING
The development and first use of production models of programmable computers (COLOSSUS)
The WWII use of Country Houses and their estates.
Vulnerability Analysis
Identifying areas of high sensitivity vulnerable to neglect or change. This may reflect life cycle analysis for more modern
structures.
General visual condition surveys have been carried out.
Seven levels of likely intervention have been identified and costed on a gross sqm basis for 5 general construction types.
A similar exercise needs to be carried out for maintenance and life cycle costs. The likely costs per building are
recorded in the building gazetteer. These figures are then used to assess the effect of the proposal for each building in
the master planning options, which in turn indicate the vulnerability of each building in general terms.
A number of principles for the future of the site are identified in this report.
Site specific policies have been developed, designed to conserve the site in general terms.
Together these will inform the Masterplan and any changes proposed to the Special Planning Guidance for Bletchley
Park in the Local Plan.
Key Issues/Objectives
General agreement as to the assessment of sensitivity for the area.
Identification of areas for further work and research
Discussion of findings with relevant Authorities to establish whether existing policies or assessments should be reviewed.
Agreement of site specific advice as to what must be preserved, what can be changed and where change will be
beneficial on a non project specific basis.
Achieving balance between conservation of existing historic fabric and proposals for new development or release of land
to enable Conservation of the remaining site and historic fabric..
Preserving and enhancing the appearance and cultural value of the area.
Informing the master plan for the site and surrounding area.
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SITE HISTORY
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