Definition of land boundaries for the purposes of ownership (the Cadastre) or spatial definition for legal and cultural purposes is a vital part of the economic foundation of our society.
The skill of measurement is the historical foundation of the surveying domain and that flows through the definition of land boundaries based the surveyor’s intuitive interpretations of historical records, field monuments and measurements and survey computations. The surveyor undertakes a rigorous process to minimise the uncertainties in all these data sources to provide the spatial definition of an indefeasible land title to government. Their importance to society is recognised by requiring ongoing statutory and professional qualification.
The cadastral (or property) layer which represents the real world cadastre is now the foundation of modern electronic GIS land administration databases which underpin good governance and decision making in public and private domains.
GIS has provided ‘map-makers’ with powerful electronic tools capable of generating plans, but originally those tools did not support the level of accuracy maintained by surveyors. Manually drafted maps were digitised to generate an electronic model of the cadastre and when accurate survey data was added, the GIS technology did not allow the preservation of that survey accuracy in the database. That has now changed.
Modern technology (GPS etc) has also introduced higher levels of accuracy in all spatial data. This has highlighted inefficiencies in many existing cartographic cadastral database technologies. The Continuously Operating Reference Station (CORS) in Australia and the MyRTKNet in Malaysia will provide centimetre accuracy to a wider range of GPS users and raise the level of position based data, further highlighting the need for an effective system to manage the underlying accurate cadastral database.
The measurement and computing technology available today has very little uncertainty in it and as such, the need for some of the old surveying skills has diminished and some of the measurement, computation and mapping role is being undertaken by a new breed of spatial professionals.
Governments are now looking for electronic solutions to provide effective survey, title and cadastral database management. Understanding all aspects of the relationship between an electronic model of the cadastre and real world cadastral definition is the key to generating practical governance within the limits of the data and the technology. This is how achievable goals can be set.
The role of the surveyor to physically define and make records to redefine legal and cultural boundaries has not changed since land ownership began, but the tools they use and the outcomes they generate have. Hand drafting title plans has moved to CAD and the electronic storing of images. Surveyors are now being asked to generate intelligent electronic records to populate databases that will generate the electronic model of the cadastre for administration and operations management. Title definition will be a consideration in the future where it has not already been implemented.
The Torrens system is recognised as one of the most effective registration systems because it is underpinned by the spatial integrity of rigorous title survey plans. Monuments on the ground or surveyor’s measurements of various precision, age and technologies are used to define those boundaries and hard copy records of those monuments and measurements are the foundation to the cadastre.
The adoption of this type of historical data into a modern exact electronic environment is a difficult process due to:
• Measurement records may be over a hundred years old and by comparison with modern tools, have poor accuracy but they still have the same legal status.
• Survey plans are allowed to have a statutory level of misclose or error in them
• Many plans are not accurate, even though they have been through a checking process when registered.
• Historical survey practices where a surveyor would think it prudent that when they were measuring the boundary of a 100 link parcel, they would actually place the pegs 101 links apart. Under the Torrens system, the original location where the peg or monument is placed defines the property corner but the title would only read 100 links. This outlines the basic edict of the Torrens system of “Monument over Measurement”. That practice, which was widespread in earlier times, is based on the philosophy that if there were problems with the survey, no landowner will complain too much if they had more land than their title states. The surveyor did not consider the problems they have just caused in the electronic future.
For these and many other reasons it is impossible to fit all the title dimensions of parcels together exactly in an electronic database but surveyors through their skill, make it happen in the real world. The solution is to replicate that same survey logic in an electronic process to generate a seamless survey geometry database. There are occasional gaps and overlaps in the real world but they are a result of poor survey practice showing a lack of resolve to solve obvious plan problems in the field and offer a solution to the registration authority.
Databases are being populated data from many sources, often of unknown spatial quality and unfortunately many people utilise those databases with little recognition of that data quality. An accurate cadastre will provide a framework to position that data as close as possible to its real position.
Many lessons have been learnt in infrastructure projects that the investment in creating a cadastral database of known accuracy will overcome undectectable spatial problems in design that only come to light during the construction stage. Service authorities (water, sewer, power, telco etc) also now understand the business case efficiencies of an accurate cadastre or at least knowing the level of accuracy in operational databases. It is unfortunate that in many jurisdictions many authorities and other levels of government commit funds to build their own more accurate cadastral databases, duplicating government databases and wasting resources.
The survey data model or Numerical Cadastral Data Base (NCDB) technology is already in use and it provides any levels of data validation. Surveyors need those tools because they have always had to certify their survey outcomes, but many spatial professionals do not consider spatial quality when they should. The NCDB technology provides a tool and an intelligent data structure to efficiently manage all levels of survey measurement data (traverse & GPS) in a GIS database environment however it is important to recognise that the coordinates generated have no legal status unless legislation is in place to provide that legal status to the model.
The fact that coordinates can change over time due to tectonic movement or updating geodetic observations is another issue of governance that not many people outside the survey profession understand. The NCDB technology manages such a dynamic coordinate environment, but generally needs surveyor’s skills in advising how to interpret the higher level of functionality available.
This is the type of tool that will make surveyors relevant to the future under the current regime of governance for boundary definition, however as the efficiency of coordinates is being recognised, the database will be seen by many with an economic bent as a cost effective cadastral definition tool. It can be, but in the right hands.
The rate of change in the electronic world is phenomenal. We are comfortable with email and web page technologies, but now we are under siege through 24/7 communications and the pressure to be active in personal and professional social networks. Data is also flooding in from these sources. Time and cost minimisation will be the biggest challenges in the future. Under most Torrens property legislation it may be difficult to provide the same quick boundary definition fix that database coordinates are perceived to provide, but this will happen in a coordinated future. The most efficient way to store any spatial data in an electronic environment is by coordinates, so in time legislation will provide that the coordinates of the cadastral database will become the prima facie survey evidence to define boundaries. That is already the case in some places around the world..
The database is a powerful land administration management tool but it can also suffer from many issues like the amount and type of data available and the expectation of outcomes. Technology can obviously solve this problem but at what cost. At the South East Asian Survey Congress (Kuala Lumpur June 2011) two plenary speakers addressed relevant issues. Dr Keith Clifford Bell of the World Bank related a growing trend in many developing countries where systems are being ‘over-engineered’ and not fit for the purpose of providing simpler or economically sustainable database solutions. The issue of utilising un-official data (crowd sourcing etc) was also raised with Professor Ian Williamson,Centre for SDI and Land Administration, University of Melbourne, Australia outlining the need for spatially enabled AAA land information (Accurate, Authoritive, Assured) at all levels. Both survey systems and survey skills can play a role in these agendas. .
The issue of 3D cadastres is now high on the spatial agenda. Numerically defining 3D objects is not a problem as the modelling tools have been around for some time. The real problem is the quantum leap in statutory governance applied to by-laws attached to the management of shared structures, services and communal areas. Trying to achieve this governance by creating a 3D mathematical model to replicate existing definition practices is not practical. The effectiveness of future electronic 3D cadastres will only be possible if a pragmatic approach to that governance is adopted. This is a role where surveyors should be at the forefront because they understand practical measurement capabilities and the relationship to practical legal definition.
In Australia, a surveyor’s options for the future are:
• Traditional custodians of the cadastre and measurement professionals (Geodesists etc) – there is a considerable decline in younger people entering or staying in this area, however the survey definition role will remain for the cadastral surveyor whilst property remains the economic foundation of our society. The success of the Torrens Title system is based on a high level of governance in property survey definition however retaining that high level of rigour must be supported by legislation. The same should apply to legal title coordinates. Highlighting the importance and justifying a higher value on that role is also a key to the future health of the profession.
• Higher Level Spatial Technologies – Individuals and companies have recognised the commercial opportunities in providing services in GIS, satellite & aerial imagery, 3D modelling, lidar etc. The rewards can be high but it can be a big investment and carries many associated risks. Individuals can provide specific consulting skills but these areas generally require the resources of the larger corporate entities and knowledge of the market & the economics.
• Somewhere in between – Servicing both of the previous domains can add value to a surveyor’s role. Surveyors are recognised for their project management skills for land development and that role should expand to a spatial data management and data validation role. A ‘shaking down’ of the industry is seeing many practioners having to make the business decision about which of the previous domains they wish to be involved with – stay small and service the 1st or grow into or join other firms to be part the 2nd. In the modern world servicing the middle ground is difficult economics.
In many Torrens Title systems like that in Australia, the transition from the “monument over measurement” edict has considerable historical legal and spatial definition issues that will not be resolved quickly. The legal status of the database as regulated by legislation is the underlying determinant of the database role for government but the awareness and understanding of that status is also important for all other stakeholders. The cadastral surveyor is the only profession that fully understands the connection between those issues and should play a major role in that transition.
Surveyor’s skills should see them have a higher role of data management and data governance in the future but there must be recognition by government and industry that these factors are important in an efficient electronic future. Spatial data quality validation and certification of that data should be a niche for surveyors that should be marketed as critical to a risk averse and litigious future, particularly to government.
Very Bad, I am sorry.
My sincere apologies. When this message was posted it seems that the main part of the message was deleted itself, leaving only this curious comment.
What I had meant to post was:
“There is an over focus on geospatial technology rather than the broader picture of land administration which includes legal and social agendas – Very bad, I am sorry. Your article, which focuses on Torrens, especially illustrates the broader role of the land surveyor and not the narrow spatial technician.”
So my congratulations on your excellent paper.
Great paper Ian. I especially agree with your comments on 3D cadastre. Saw you present in Melbourne, last year, well done.
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Professor David Last
Consultant Engineer and Expert Witness in an interview with Coordinates while sharing his views on a range of issues pertaining to GNSS technology
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