Updating cadastral base maps: An innovative approach

The accuracy, attainability, and affordability of base maps are vital for an effective land administration system, yet not always reliable in many countries, regardless of their level of development. Obstacles such as limited financial and human resources, inadequate infrastructure and the unavailability of technology and tools hinder the establishment or provision of accurate and reliable base maps. Volunteered Geographic Information (VGI) has been regarded as an affordable alternative in prior studies and has been implemented in several pilot projects across various countries, primarily in developing countries. However, spatial accuracy is often sacrificed as a trade-off to ensure affordability in these past implementations, making the past attempts unsuitable for base map upgrading purposes in developed countries, as the achieved level of accuracy fails to fulfil the accuracy requirements such contexts. This paper presents an innovative, feasible, and affordable approach to providing a low-cost yet accurate and reliable solution to this issue. By integrating a user-friendly mobile application, GILA (Geographic Information for Land Administration), with a portable and highly accurate external GNSS unit, the app enables citizens with little or no professional experience to accurately collect land parcel corners through a participatory approach. The participants need to be trained to survey land parcels by capturing parcel boundaries while in the field. Two case studies were conducted to evaluate the device and assess its potential for collecting land and property information in real-world scenarios. The results demonstrate that GILA is an accurate and affordable solution that meets both the required standards and the stakeholders’ accuracy requirements.