Reliable 2D Crowdsourced Cadastral Surveys: Case Studies from Greece and Romania

Abstract

This paper is part of a doctoral dissertation (PhD) research that investigates the development of a procedure for reliable 2D crowdsourced cadastral surveying introducing the use of new Information Technology IT tools and increased citizen participation, supported by m-services. For the development of this procedure, the formal cadastral procedure applied currently in two Europeans countries, Greece and Romania, for their modern nation-wide projects is firstly investigated. The first part of this paper briefly investigates the current stage of progress of those projects in both countries, as well as the specifications and procedures applied for the cadastral surveys, and assesses the level of participation of the right holders and the efficiency of the current procedures. Then, a proposal for a crowdsourced general procedure with increased participation of the right holders in the initial cadastral data collection phase is designed that it may be of value either for the planners of those two projects to improve their projects towards a more fit-for-purpose approach and successfully meet the deadlines timely, or for researchers and planners of other projects with similar nation-wide approaches which also require accurate, assured and authoritative end products. For the assessment of the applicability of the proposal, three case studies are held and tested in urban, rural and suburban areas in both countries, using both a commercial application and an open source one. These crowdsourced surveys are compared to the formal cadastral surveys that have been compiled by cadastral professionals in both countries and the achieved results are assessed and judged as satisfactory in terms of geometric accuracies and the avoidance of gross errors in the location of the parcels. A proposal for future research in order to further improve the proposed procedure is discussed.

Design of a Crowdsourced 3d Cadastral Technical Solution

“…In countries with no updated 2D cadastral maps, first a digital 2D cadastral map must be compiled, by identifying the land parcels and the building footprints on it. In this case, an appropriate basemap could be an exciting recent orthophoto, or if not available an aerial photο taken from various platforms (e.g., UAVs), or even the OpenStreetMap (OSM), with gradually descending precisions; a more detailed methodology for 2D crowdsourced cadastral surveying is given by (Potsiou et al, 2020). To simultaneously proceed with 3D cadastral recording, additional information regarding the height of each property unit; the level above or below the ground where the property unit is located; as well as each property unit outline related to the declared rights, should be collected.…”

“…Practical experience has demonstrated the significant benefits in crowdsourcing geodetic measurement from multiple organisations (Haasdyk, Roberts, 2013). Web-based and mobile-based crowdsourcing solutions, have already been used in developing 2D cadastral surveying procedures in order to minimize the time and cost of the required surveys (Basiouka, Potsiou, 2014;Mourafetis et al, 2015;Basiouka et al, 2015;Gkeli et al, 2016;Basiouka, Potsiou, 2016;Apostolopoulos et al, 2018;Celt et al, 2019;Potsiou et al, 2020;Potsiou et al, 2019;Mourafetis, Potsiou, 2020). The existing 2D experience should be exploited in 3D cadastral surveys, providing a fit-forpurpose solution for the initial implementation of reliable 3D Cadastres.…”

“…The absence of a functional cadastral system enhances right holders' uncertainty regarding their rights, increases risks, time and costs in land and property transactions and mortgages, blocks the real estate market and disables poverty reduction. The indtroduction of low-cost and modern IT tools, crowdsourcing techniques, automated procedures, m-services (mobile services) and international standards, such as the LADM standard, in 2D and 3D cadastral surveys, may speed up the cadastral procedures, reduce costs, enable harmonization and exchangeability of data, and eventually may lead to the immidiate implementation of a functional 2D and 3D cadastral system, everywhere (Apostolopoulos et al, 2018;Potsiou et al, 2020;Mourafetis, Potsiou, 2020;Gkeli et al, 2017;Gkeli et al, 2018;Gkeli et al, 2019ab). The use of volunteers' mobile devices as the main mean of 2D and 3D data capture, reduces the cost and time of the overall procedure, as each one may be responsible for the declaration of his/her own properties.…”

Crowdsourced Geospatial Infrastructure for Coastal Management and Planning for Emerging Post COVID-19 Tourism Demand

“…Crowdsourcing seems to be an effective practice for the collection of reliable geospatial information for various land administration and planning purposes [34][35][36][37][38][39][40][41], as well as tourism, heritage, and travel plans [42,43]. Several recent European Commission projects in this field were mainly based on crowdsourcing techniques, in which people are used as "sensors" [44].…”

IT Services and Crowdsourcing in Support of the Hellenic Cadastre: Advanced Citizen Participation and Crowdsourcing in the Official Property Registration Process

“…Other studies focused on the efficiency of applying crowdsourcing in land administration in the post conflict and developing world [25][26][27][28], in order to speed up the cadastral surveying and the first registration process in the economies in transition [29,30]. Once researchers and cadastral surveyors were convinced about the reliability and/or the efficiency of this technology international research was continued on developing a methodology for ensuring and motivating increased people participation in the cadastral surveying [31]. Research in this field also continues in investigating tools and methods for using crowdsourcing and smart phones or other low-cost technology for the compilation of 3d reliable cadastral surveys [32][33][34]; as well as in introducing it in the general work of the land surveyors and in the official map production [3,35].…”