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This paper considers the procurement and implementation within a short timescale of a Land Information System for Milton Keynes Development Corporation. The administration of the procurement contract is discussed and some areas of confusion highlighted. Reference is also made to the new structured map base available in the UK and the difficulties encountered in relating legal plans to this base.
Steve Gill is the GIS Manager for Midsummer Computing. A graduate in Earth Sciences, he entered the mapping industry in 1966 and has been involved with the Milton Keynes project since its inception. He is now one of Midsummers' IRC staff. Ken Robinson, a maths graduate, is a long serving officer within the civil engineers department of MKDC. He now manages the LIS Department on behalf of the Corporation.
Milton Keynes Development Corporation (MKDC) was formed under an act of parliament in 1967 and is responsible for securing the development of the New Town of Milton Keynes. It has already enabled the population within the designated area to rise from 40,000 in 1967 to over 149,000 in 1991. The development of Milton Keynes has been based on the creation of substantial employment opportunities, supported by a major housing programme with related retail, leisure and other facilities. Further substantial development and population growth is planned for the 1990's. However, after 31 March 1992 the role presently exercised by MKDC will be performed by other public and private bodies.
In 1988, with the corporation's wind up date in 1992 rapidly approaching, MKDC decided to implement an LIS as quickly as possible. The LIS would primarily be used to capture the boundaries of all the land transactions (both acquisitions and disposals) entered into by the corporation. The data set would therefore represent the total land area which had passed through the corporations hands during the period from designation in 1967 to wind up in 1992.
This major information overlay would enable quick access to up-to-date information, thus enabling potential problems involving property boundaries and land areas to be addressed more rapidly and thus speed up the disposal process. The system would also enable the production of disposal plans and customised Ordnance Survey map sheets with, if required, superimposed MKDC overlays. However this set of themes although central to the MKDC LIS project was just one of a number of disparate themes. Information was also to be held on planning approvals, landscape details and constraints to development.
During November 1988 an initial feasibility study was undertaken within MKDC. The study concentrated on the uses of the proposed system, prioritised these uses and defined a set of criteria regarding the capabilities of the selected vendor and the equipment to be purchased. The study recommended that the system implementation, including system acceptance, should be completed by 7th August 1989, effectively seven months later.
The feasibility study confirmed the need to computerise MKDC's land transaction deals. These transactions include acquisitions, freehold disposals, shared ownership disposals, and leasehold disposals. In order to arrive at the 'definitive disposal plan' additional items needed to be incorporated. Other overlays were also identified at this stage. These were categorised as:
This last category comprised mainly small overlays which would be relatively easy to capture and could thus be used for staff training. In consequence some of these themes were implemented prior to the completion of the essential items.
As the Ordnance Survey of Great Britain had already produced 1:1250 digital mapping for the city area, the feasibility study recommended the use of structured vector data using a new National Transfer Format (NTF) for the whole of the city. The main advantage for MKDC in using this data resulted from it having been cleaned mathematically in order that polygons could be formed within the OS specification.
This structured base mapping product or OSBASE can be used to generate typical OS 1:1250 map sheets and is comparable to the traditional "spaghetti" map data. However OSBASE also contains additional data comprising polygons and centroids defining the extent of buildings, areas of vegetation, slopes and water. These polygons allow the user to generate sophisticated colour plots with minimal effort. They also increase the data set size and consequently the time required to process the data to produce graphics files. All the information within the MKDC LIS themes are referenced to the OSBASE data set which thus comprises the base mapping within the designated area.
The main advantage of OSBASE structured data to MKDC is that the line-work is mathematically "clean". There are no overshoots and undershoots. Consequently all line-work intersects precisely and each point of intersection on a linear feature marks the end point of two or more linear elements. The subdivision of long linear elements into their shorter components is of considerable use to MKDC technicians. They are able to identify and copy into their various themes only those linear elements applicable to the land transaction they are working on. Using the traditional "spaghetti" data it would be necessary to partial delete, modify and intersect the copied features to create the clean line required for the land terrier polygons. When a boundary on a legal document is not represented in the OSBASE data set, traditional digitizing methods are used to generate the line-work.
It was felt that the vendors should be given the widest possible choice of hardware and software platforms to meet MKDC's requirements because it was deemed that the functionality of the system was paramount. The tender document thus specified no particular hardware or software but concentrated primarily on the functionality required from the system.
The tender took four weeks to draft from scratch. As there was only a short period allowed for the evaluation of submissions, it was advantageous that each tender was received in a similar format; there was no time available to 'compare apples with pears'. To this end it was decided to use the CCTA Conditions of Contract (1988); these conditions of contract are applicable to all central government new technology procurement contracts. Throughout the pre-contract phase the requirement that all the tenderers were treated even handedly was uppermost, this in the authors view makes the tender adjudication far easier.
The tender comprised the following sections.
A liquidated damages clause was included in the contract. This caused vendors some concern, however it was intended to concentrate the efforts of the supplier in meeting the tight implementation schedule. It is understood from discussions with suppliers that this clause is not usually included in GIS procurement contracts but the authors would recommend that it is included in any other fast track implementation. Including such a clause in the contract imposes a high level of commitment on the purchaser as well as the supplier because delays caused by the purchaser could lead to dispute concerning liquidated damages.
A short list of seven vendors were invited to tender based on the following criteria:
Tenders were sent out on 20th January 1989 and in the event, five valid bids were received on 20th February. As the invitation to tender was received by vendors who had experienced very little initial contact with MKDC, many of them, including Intergraph, erroneously assumed that the corporation had already been involved with long discussions with one of their competitors.
During the period when the tenders were being priced, a set of typical data was compiled within a 1 km square. This data was selected to allow the chosen vendors to prepare a prototype system for benchmarking. The benchmark was scheduled to take place approximately thirteen working days after each of the four lowest tenderers had attended individual meetings with MKDC representatives to discuss the benchmark. At the end of each meeting the tenderers were asked if they wished to compete in the benchmarking process and the prepared data set was handed over. This data set comprised copies of acquisition and disposal plans, textual data and four OS 1:1250 sheets of the new structured data delivered in NTF level 3 format. The data was accompanied by a seven page document describing various textual and spatial queries which were to be performed on the dataset provided to each selected vendor.
Although thirteen days was considered a short time to prepare the benchmark, all the suppliers had originally confirmed that they already possessed a working Land Information System. Thus it should only have been necessary to enter the provided data into the existing system and perhaps build a customised front end. The ability of the vendors to complete the benchmark within this period was seen as an indication of their ability to meet MKDC's fast track programme. In the event one vendor withdrew at this stage.
Each of the short listed vendors were required to demonstrate their prototype system on their own premises. Because of the fast track programme only one day could be allowed for the assessment of this prototype by the MKDC benchmark team. This team, although small, was thought to be well balanced; containing people with intimate knowledge of MKDC, land transactions, digital mapping, databases and a working knowledge of the various hardware platforms.
In order to more accurately reflect the situation in the final working system a 100 M byte map base was simulated by copying the four supplied NTF quarter km sheets to other map locations, thus increasing the volume of base mapping stored on the system. Ideally the prototype system should have been demonstrated using the hardware configuration which the vendors were offering in their tender submission. In practice this was not achieved. It was recognised that response times achieved in the benchmark were not indicative of those which could be expected from the complete LIS due to the differing hardware configuration and the impracticality of providing a full size database.
The assessment of the prototype system was based upon system functionality, ease of data entry and also the systems ability to handle the newly released Ordnance Survey structured data; this being supplied using the new National Transfer Format (NTF level 3). A weighting was attributed to these criteria before the prototype systems were seen, as it is easy to become overawed with the customised screens and other 'bells and whistles' which the vendors stress on the day.
The authors never expected any vendor to meet the full requirements of the benchmark and this proved to be the case. It was also apparent during the benchmark how much effort Intergraph had put in to secure this contract.
After performing the three benchmarks ( one company withdrew ) Intergraph was chosen unanimously by the benchmark team as the successful tenderer. Some negotiation with Intergraph then took place in order to define the system acceptance tests. This is necessary to allow the completion of the contract to be agreed and therefore to remove the supplier's liability for liquidated damages. With very minor variations the system acceptance tests relied on the same functionality as that defined in the benchmark document.
The ensuing contract negotiations, covering aspects such as training and maintenance, enabled MKDC to commence building a good relationship with Intergraph's staff. The authors felt it was important, during these meetings, for them to be able to gauge the spirit in which the contract would be administered. As a result of the fast track programme the authors felt that the overall approach to the contract had to be pragmatic both from MKDC and Intergraph.
The official order for the system was placed with Intergraph on 6th April 1989; this date was only 15 working weeks after the feasibility study was accepted by committee. Intergraph then had 16 weeks available during which they had to install the hardware and carry out system customisation prior to the programmed contract completion date of 7th August.
During the installation period, Intergraph experienced two weeks delay because of circumstances beyond their control. Consequently the completion date was moved back to accommodate the delay. The Ordnance Survey supplied the 1:1250 digital maps to Intergraph and the system was subsequently delivered with the maps loaded. Intergraph engineers caused minimum disturbance to the every day running of MKDC during the installation, and gave the authors no cause for complaint.
Prior to the installation, during May, a small team comprising MKDC, Intergraph and Midsummer Computing staff spent three weeks discussing each of the identified map overlays, thus allowing Intergraph to gain a working knowledge of the existing paper system. Also during this period full symbology tables were prepared for all the features on OS maps and proposed MKDC overlays. These tables, prepared by S. Gill, defined how the features were to be represented both on the screen and on hard copy plots.
The information gathered by Intergraph during this workshop enabled their engineers to create a package of commands, menus and interfaces which met the requirements of MKDC. The customised LIS was ported to the hardware supplied to MKDC and was subsequently demonstrated to the satisfaction of the authors prior to the designated system acceptance date.
A period of staff familiarisation and system testing ensued. A few minor problems were encountered during this period. One minor misunderstanding related to an assumption that the representation of parcels followed topological rules relating to polygons and therefore that parcels on conveyance plans could not overlap. In actual fact it is these unintentional overlaps we wish to identify. Once their mistake had been realised Intergraph responded rapidly and made modifications as necessary. This level of response and cooperation has been typical of Intergraph throughout the project and has ensured that MKDC has kept on the fast track.
Data capture started in earnest at the beginning of September 1989 and is proceeding satisfactorily. However the length of the learning curve was underestimated especially in those areas peripheral to data capture, such as the production of sophisticated plots and data manipulation. In this context it was found to be very beneficial that MKDC had recruited some staff with both Intergraph IGDS experience and also cartographic qualifications.
As previously stated the system is being used to input details of legal land ownership transactions, particularly the boundaries of the land parcels. Once these parcels have been captured, analyses can be conducted so that the MKDC land holdings can be monitored, and perhaps more importantly, boundary mismatches can be identified.
Most people will be aware that in Britain our land registration and property transfer system is not based upon a cadastral survey. It may be beneficial to briefly explain our system of land registration. The land registry in fact holds a register of the title to land. Prior to compulsory registration the unregistered title deeds may have contained 'no more than an inconclusive verbal description without any attached plan' (Ruoff & Roper 1986); when land was transferred the vendor was required to produce proof of title which could be traced back over a reasonable time, say thirty years. Compulsory land registration commenced in London at the end of the last century and was gradually extended to cover the whole of England and Wales by 1990.
The register comprises three parts; the property register, the proprietorship register and the charges register. The property register contains a verbal description of the property and also describes it with reference to an individual plan relating to the particular title alone, rather than a section of a general map. The plan used is almost certainly to be a copy of an Ordnance Survey plan, probably at 1:1250 scale. In Britain we do not use surveyed permanent boundary markers to delineate the property. The proprietorship register holds information about the nature of the title, whether absolute or leasehold, together with details of the current registered owner. The charges register contains details of all incumbrances on the title.
Where discrepancies occur between the legal plans attached to either the register or the previous conveyance document, the guiding principle as to the extent of the land parcel is the intention of the parties entering into the transaction. The legal documents should therefore reflect this intention, if they don't then the parties involved become involved in complex litigation to prove intention. This principle of intention can act as an excuse for some parties to use plans which are less than ideal and show an approximate spatial position for the parcel.
Now it can be seen from the above that in capturing data concerning recent transactions as well as historical ones we are dealing with both registered and unregistered titles. The recent titles will have been transferred using an Ordnance Survey plan as a base. However this does not alleviate problems as in a rapidly developing area the base map changes frequently. (Half our base map sheets are revised each year). Where the transaction is based on a conveyance then the plan attached is probably quite old because of the necessity to prove that the title is sound (proving root of title).
Land transaction plans have therefore been recorded with varying degrees of accuracy on varying quality base maps. Because of these variable standards, it is not always possible to simply transfer detail from a legal plan to the OS base mapping - the detail has to undergo a transformation in order to obtain a best approximation to reality. These difficulties are compounded in a new city where land is often acquired as green fields. Thus conveyance plans are often based on early mapping of open countryside whereas the digital map base is of the subsequent developed urban area.
In a few instances the conveyance plan is an original hand drawn document dating from the 1850's. These plans present problems when they are referenced to the national grid. Similarly some conveyances recorded on the County Series OS maps show a seven metre spatial discrepancy when related to the current digital map base.
Another area of discrepancy occurs where a boundary depicted on the OS base mapping fails to correspond with the disposal boundary defined on a legal document. There are two major reasons for such discrepancies. Firstly the builder failed to erect the fences in accordance with the conveyance plan or secondly, the householder has 'grabbed' extra land by subsequently moving fences. This second category of discrepancy is a significant proportion of those found. The interpretation of boundaries on legal documents is thus not a straightforward exercise. Each LIS technician involved in the input of legal boundaries has to make decisions relating to the boundaries represented on the OS digital map base. For example ".... is the boundary depicted on the old County Series map truly the same as that on the base mapping - the alignment is slightly different, but it appears to have the same configuration and spatially it's just about in the right place....".
In capturing the detail of overall planning approvals within the New Towns Act a different problem is encountered. These section 7(1) approvals are granted with reference to a plan, usually at 1:2500. However the boundary of the approval is represented as a line one centimetre wide. Section 7(1) approvals are intended to overlap with their neighbours and any revision to a previous approval does not replace the earlier approval but co-exists with it. When this detail is entered into a LIS then otherwise imprecise data suddenly has an apparent precision of 1mm. Not only does one have to devise procedure to hold this data so that its source is evident but one also has to decide whether the apparent precision of the boundaries within the system introduces a risk for the future.
Initial graphics entry is followed by the production of check plots for each transaction. These plots are scrutinised by experienced staff and marked for later editing. Only when the edits have been satisfactorily carried out is the graphics component of a land transaction deemed to be validated.
Discrepancies identified by the system are reported back to the client departments so that remedial action can be instituted. An LIS will not provide the answer to these problems; it will only highlight them for others to resolve. Allowance has had to be made to obtain sufficient resource in the client department to be able to resolve these discrepancies.
It was originally intended that the workstations should be distributed around the various departments of MKDC. However the machines were installed centrally whilst initial configuration and training took place. It soon became apparent that these arrangements lead to tighter control of the system and enabled an interchange of ideas and methods during the crucial learning period.
During the system review which took place after four months it was agreed to maintain the workstations as a central resource and to continue the secondment of some staff to the LIS department. The server/client relationship between the LIS department and the user departments was also formalised at this time.
This paper has concentrated on the benefits derived from MKDC's LIS and has not discussed the benefits obtained from having a current up to date digital mapping system. Many departments within the organisation spend time in photocopying, cutting and pasting together map sheets to meet their needs. The LIS provides the facility to window an area and produce a hard copy of the base map within 10 minutes. This valuable and rapid facility if left unregulated could have absorbed more than 40% of our available workstation resource. Initially the decision was taken to limit this usage to 20% of that resource. Thus meaning, that in many cases only base plots were produced from the system; any enhancement being carried out by the client department. Bromley and Coulson (1989) address the benefits obtained by Swansea City Council from the digital mapping aspect of a GIS in more detail in their paper. These benefits are typical of those experienced by MKDC. However as the disposal process has speeded up then the requirement for more plots and also more sophisticated plots has increased. Now only 10% of the plots produced by the system are base mapping the rest having been extensively manipulated by the operator.
The system is now on a fast track data capture programme concentrating on the conversion of land terrier records. Equipment is being operated ten hours a day seven days a week using two teams working a four day on four day off rolling week. In this way utilisation has been doubled with comparable gains in data conversion schedules. Some overlays have also been contracted out for digitisation.
The system is to be passed to the residuary body after the wind up of MKDC on 31st March 1992. As this system now contains the only up to date record of land transactions entered into by MKDC it is currently, (July 1991), expected that the Commission for the New Towns will continue to use the system to expedite the disposal of assets and to manage the land held by the Commission.
The initial corporate aim of having the system up and running in August 1989 was achieved. The authors are convinced that this fast track implementation programme can be followed by any other organisation provided that there is total commitment both by the managing committee and the staff involved. Other organisations who wish to implement such a programme should be prepared to hire in expertise where their own staff lack the necessary experience. The use of one of the members of the IRC programme has been of inestimable value to MKDC.
The corporation has a great deal of experience in managing multi-disciplinary projects and this experience was found to be invaluable during this implementation. Any GIS implementation is going to cross discipline boundaries and staff must be prepared to educate themselves within the new areas.
If one desires to achieve a fast implementation then the spirit of cooperation between the client and the vendor must be paramount in their contractual dealings if the project is to be a success.
BROMLEY, R.D.F. and COULSON, M.G. (1989) 'The value of corporate GIS to local authorities'
Mapping Awareness 3(5):32-35
CCTA (1988) 'Rules for Tendering and General Conditions of Contract.'
Central Computer and Telecommunications Agency, HM Treasury
RUOFF, T.B.F., ROPER, R.B., PRYER, E.J. & WEST, C (1986) 'The Law and Practice of Registered Conveyancing'
Fifth edition, Stevens & Sons, London
| Copyright © 2001 Ken Robinson |
