A
couple of small points here:
1.
The
concept of needing to keep all records on one “layer” and therefore forcing them
all to share the same geometry type (if indeed this is behind the decision) is
arguably short-sighted, and tied to the particular GIS technology stack (ESRI)
that EH happens to use. In some existing GIS technology no such constraint
exists, and as we move more towards spatially-enabled databases and away from
proprietary GIS formats, this will become less relevant. It would be shame if an
important dataset is made less useful for this reason
alone.
2.
Graham
asks a good question about WMS/WFS (and note that the SMs are already available
within the SHINE WMS), however we should not consider this the whole solution.
Yes, this would be helpful sometimes, to cross-check. However services like this
will not (for a long time) be usable in automated constraint-checking systems
etc, and it will usually be necessary to hold a local copy, properly indexed
into (and managed by) the HER. Furthermore, it is also extremely important to
know when designations change, and a WMS/WFS cannot tell you this. In theory EH
could run web services that respond to requests for lists of changes, but I’ve
not heard this proposed, and I cannot see this happening any time soon (though
it would be the correct technical solution IMHO). In the meantime, the
notification procedures will remain crucial, and each will require some updating
at the receiving end. This should not necessarily be criticized as
double-handling – it is important part of making sure designation changes take
effect in policy and practice.
Cheers
Crispin
From: Issues
related to Historic Environment Records [mailto:[log in to unmask]] On
Behalf Of Graham Tait
Sent: 24 August 2010 16:31
To:
[log in to unmask]
Subject: Re: Statement on Spatial Depictions
of Heritage Assets - message on behalf of English Heritage Heritage Protection
Department
I have read this
thread on the proposed Unified Designation System with some interest.
As Chris points
out, English Heritage have a practical reason to integrate all the
assets into one layer, therefore combining separate datasets of points, polygons
and lines into one dataset.
I understand that
polygons of Listed Buildings do not have any statutory validity. The mapping
component of the database needs to clearly indicate which building is listed.
In the last few
years, English Heritage have been creating polygons (rather than points) of
Listed Buildings for records that have been updated recently. These polygons
have been very useful for identifying individual Listed Buildings. While
these don't indicate the curtilage, they do clearly indicate each Listed
Building. This needs to be made clear in the metadata provided.
It seems to me that
by converting all of the Listed Building entries to 5m x 5m polygons is
rather 'throwing the baby out with the bathwater'. Another approach might be to
keep the polygons of the buildings that have already been captured, and convert
only the points into 5m x 5m polygons?
It would also be
useful to know if English Heritage are planning to make the Unified Designation
System mapping available as a Web Map Service (WMS) or a Web Feature
Service (WFS)? This would stop the double-handling of data as it is
updated by English Heritage, and then updated again by each local
authority and other interest groups. At the moment, we have to download data
from http://services.english-heritage.org.uk/NMRDataDownload/,
and keep checking this and regularly downloading it to ensure our data is
up-to-date. Making this available as a WMS or WFS would mean that the most
accurate and up-to-date data could be shown directly on any GIS throughout the
country.
As Crispin mentions,
it would be useful to know the thought processes behind the decision for
the Unified Designation System, and whether there is any room for discussion or
change.
best
regards,
Graham
--
Graham Tait
Archaeologist
Historic
Environment Service
Devon County
Council
Matford Offices
County Hall
Topsham
Road
Exeter
EX2 4QW
Telephone: 01392 382214
Email: [log in to unmask]
Web: http://www.devon.gov.uk/historicenvironment
Disclaimer: http://www.devon.gov.uk/email
-----Original Message-----
From: Issues related to Historic Environment Records [mailto:[log in to unmask]] On Behalf Of HOWARD, Bruce
Sent: 20 August 2010 16:40
To: [log in to unmask]
Subject: [HERFORUM] Statement on Spatial Depictions of Heritage Assets - message on behalf of English Heritage Heritage Protection DepartmentDear List member,
Please see below a statement issued on behalf of English Heritage's Heritage Protection Department:
"Statement on Spatial Depictions of Heritage Assets
English Heritage is in the process of undertaking a programme of work designed to reform the way in which the currently separate designation systems of Listing, Scheduling, Protected Wrecks and the two Registers of Parks and Gardens and Battlefields are created, managed and stored.
A new database is being created called the Unified Designation System (UDS), which will not only support the new unified business process but it will also contain all the individual designation records and make these available via the online Heritage List for England. Each record will contain both a textual description together with a mapped indication of the location of the asset. The UDS and the Heritage List for England will also contain World Heritage Site records. The UDS is planned to go live in early 2011.
Currently the various types of designation are spatially depicted by a mixture of points, polygons and multi-part polygons. Each is stored as a separate dataset in the current Geographical Information System (GIS). To ease software development and future maintenance the decision has been taken to move all these depictions to a single dataset in the new system.
To enable this to happen it has been agreed to convert all Listed Building entries currently depicted as points into tiny polygons of size 5m x 5m. There are, however, a number of Listed Buildings which are already depicted as larger-scale polygons, some with multiple parts. It is not possible to migrate these across to the new system as they do not have any statutory validity and they might also be mistakenly taken to indicate curtilage. It has therefore been decided that these depictions will also be converted into tiny polygons.
The polygons with multiple parts will be gradually converted over the coming months, with the remaining larger-scale polygons and the points converted all together when the new system goes live.
For Scheduled Monuments, Protected Wrecks, Registered Battlefields and Registered Parks and Gardens the polygons will remain as the spatial definition of the designated area.
The different asset types will continue to be available to all users as separate datasets via the NMR Data Download Area."
Regards
Bruce
***********************************************************************************
Bruce Howard
Heritage Information Partnerships Supervisor (HER Liaison)
English Heritage
National Monuments Record
Kemble Drive
Swindon
SN2 2GZ
Tel: 01793 41 4880 Fax: 01793 414444
e-mail: [log in to unmask]
mobile: 07979 241 770
Online guidance for Historic Environment Records: www.ifp-plus.info
HER Forum email list owner:
P Please consider the environment - do you really need to print this email?