Google Earth for Cadastre use?
According to some comments on some blogs, it seems Google Earth's scope will go beyond the initial web localization purposes; such is the case of the applications that are being oriented in the cadastre area. The Diario Hoy of the city of Mar de Plata publishes a case, in which it is being brought to the legislative level for georeferencing and valuation purposes.
In general, the laws of the municipalities or city councils establish the collection of real estate tax as a tax power that allows them to obtain resources, which can be reinvested in projects that improve the quality of life of its inhabitants. For this, the well-known “cadastral values” are used, and although there are different methods for their application, the purpose is for the owner of a property to pay a tax proportional to the “value” of the property for the costs that the municipality implies to provide public services and as a contribution to autonomy in the aspect of self-sustainability.
Undeclared assets are usually the ones that cause the greatest degree of complexity at the time of application of tax obligations and it is in this area that Google Earth is intended to be used in order to detect urban improvements and permanent crops. Apparently the instrument in Mar de Plata is only oriented towards the estimation of the tax, not for the appraisal notification or for the geometric definition of the properties since it is known that Google Earth images have a variable level of vagueness Because the terrain model used for orthorectification is conditioned by the number of control points; In this way, localities in developed countries have advantages with the number of geodesic points and "almost public" use.
The proposed law contains in one of its sections the following paragraph:
"When for reasons beyond the management of Cadastre There are territorial objects (houses or departments) that still form part of a cadastral parcel are not represented in an approved plan and registered according to the current regulations, that agency can individualize them, register them and assign them real estate by means of alternative methods of territorial delimitation that guarantee levels Accuracy, reliability and completeness comparable to the acts of measurement "
The proposal becomes interesting (technically dangerous), since ballots and charges can be issued, those that exist until the applicable administrative and technical procedure is carried out, which is usually an affidavit, the technical process that can be the property measurement, valuation Of land, identification of use and calculation of the tax according to the improvements or permanent crops.
Each time information technologies become more accessible and easier to manage, of course the risk is high, as it happened when all the children who learned to use ArcView decided that they did not need to learn cartographic concepts. Now whoever knows how to use Google Earth will say that he does not need to know geodesy?
Ultimately, the use of data such as those offered by Google Earth is a great solution in countries where there is no recent satellite image or orthophoto; many times because state agencies are weak in providing these services to municipalities. So if it comes to identifying swimming pools, new buildings, housing estates or areas of permanent cultivation, surely Google Earth can be a great ally. The same cannot be said if the information is to be used for legal purposes or the data is mixed with more precise surveys without making a differentiation that alerts new employees to a change of government.
In which country are you?
Ideally, you should look for a professional, as each country has different conditions of legislation regarding land regularization.
Buy a property, 6 years ago, and scripture 1 year ago, now I know that the previous owner had started the subdivision ,,, not remember that home surveyor, what should I do to continue with it, since I am interested in subdividing it ,,, Thank you
I think that for planning purposes it works well, but for serious work the tool really is not that it does not have the capabilities but for that there are specialized tools and data.
To give an example, GoogleEarth has an orthorectified satellite image or even an orthophoto of aerial photography origin with a pixel of one meter and even smaller, which suggests a relative radial error of about 1.50 meters, but the absolute errors of georeferenciación walk by the 30 Meters. this is an example
In Spain the cadastre uses Sigpac (http://sigpac.mapa.es/fega/visor/) That I imagine could be used legally when belonging to a ministry.
In theory its accuracy must be greater, having been raised from the beginning for these purposes.
What appears here as a technological innovation is nothing more than what we call in Argentina "A Patch" or a precarious solution to a situation that in this case is the lack of cadastral surveys in the province of Buenos Aires. I believe that the solution presented is not serious and that it is not developed according to the transcribed text of the cadastral law that says: "...alternatives of territorial delimitation that guarantee levels of precision, reliability and comprehensiveness comparable to the acts of measurement"
In fact, Goggle Earth has a design that prioritizes the display of some type of information taken on an unknown date, in unknown conditions and who knows what other things. It is not a product that can be considered technical. A cadastre with all of the law that guarantees both collection and respect for the rights of the citizen requires the application of the techniques and quality standards corresponding to the survey of this type of information and not a "blackmail" (Argentina: negligent improvisation) .
Goggle Earth is a great tool and very good if used in the context in which it was created. The extension of its capacities in lands that do not correspond to it by unsuitable people quickly leads us to completely absurd cases such as the one mentioned above about "to know how to use Arc-View it is not necessary to know cartography".
What is raised in the article is possible, only if you have high resolution information and, as you yourselves recognize it, Google Earth, with cartographic purposes is very variable. On the other hand, the information, although it is useful, is not found in real time, this means that the possible modifications of the movable property are not detected, and it inculcates the change of land use, with which the work of cadastre registration It is very imprecise. However, in general terms, the ideas presented in his article are very useful. Greetings from José Ramón Sánchez, Pregonero, Venezuela, Edo. Tchira