Geographic information systems (GIS) are extremely useful for mapping and collating data on potential risk based on spatial data. But how can you incorporate people’s vulnerabilities and capacities in such assessments? Mapping together with local communities can be solution here.
“Maps have the power not only to interpret, but to transform and create the landscape. Maps, indeed, can change the world.”
(Global Assessment Report on Disaster Risk Reduction, UNISDR)
What is PGIS?
New spatial information technologies open up new possibilities but not for everyone. This usually follows the lines of existing power structures in a society. Participatory GIS (PGIS) evolved from the need to make such technologies available to all groups in society. This way disadvantaged groups have more access to and capacity to participate in generating, managing, analyzing and communicating spatial information. Thus, one of the main goals of participatory mapping is to empower local communities through demand-driven, user-friendly and integrated applications of geo-spatial technologies.
Other terms: PPGIS and VGI
Two other terms that are used in this context are Public Participation GIS (PPGIS) and Volunteered Geographical Information (VGI). There are some slight differences in purpose, representation of geospatial information, and modes of participation, but in general these are similar methods and sometimes they are used interchangeably. PPGIS is becoming a mainstream tool to integrate scientific data and local values and knowledge for creating sustainable and livable cities and environments.
Potential for Disaster Risk Reduction
PPGIS has a lot of potential for disaster risk reduction. Simply combining existing maps with local knowledge on vulnerable infrastructures and people’s capacities to respond says a lot more then only scientific data. It enables communities to prioritize risk prone areas, increase their preparedness, and develop scenarios and action strategies in the event a disaster will happen. Its application can be top down (as a tool to broaden public involvement in decision making) or bottom up (to promote the goals of NGOs, grassroots groups, and community‐based organizations.
Tools for Mapping Together
Many different tools and methods have been developed for participatory mapping. New media and ICT have greatly changed the ways in which mapping is possible, both in terms of scale and technologies. Which method works where, however depends on the ‘e-readiness’ of a country. In rural areas with low internet coverage it is best to use more traditional methods such as hardcopy maps. Digital mapping has the potential to reach many people in urban settings. A good overview of the basic forms of participatory mapping for disaster risk reduction is presented in this infographic (based on Cadag and Gaillard, 2012).

Platforms and Communities
If you are interested in using PGIS, there are a number of online platforms and communities that offer guidance.
- This website on Integrated Approaches to Participatory Development has been developed by Giacomo Rambaldi and gives a good overview of different approaches (including a handbook).
- PPgis.net is a digital platform for discussing issues, sharing experiences and good practices related to community mapping. It also lists a number of open source technologies to support data collection, integration and visualisation.
- Commercialised versions (such as Maptionnaire from Mapita in Finland) are also available and could be of potential interests for local governments and urban planners.
- This blog gives you the latest news and opinions on PGIS and PPGIS practice, including some interesting case studies using Participatory 3D Modelling (P3DM).
- And if you want to present your work or learn from other, visit the 2019 conference of the International Society of Participatory Mapping Conference in June next year: Let the people map!

Good Mapping, Good Governance?
New developments in geospatial technologies enable rapid sharing of diverse geographic information for disaster management at low costs. But they also present new challenges, such as data quality assurance, data management, personal security, and growing inequalities. Its potential may well be in the disaster preparation phase and to strengthen community resilience to potential disaster events. Doing PGIS is not a neutral exercise and a series of questions (about who is mapping, for whom, and how is the information used and made available) can inform you whether your mapping is also an example of good governance.
PGIS certainly fits the trend of the UNISDR to develop people-centred early warning systems and disaster risk reduction. A scoping study on the potential use of PPGIS in Kerala, India explored the possibilities of incorporating local knowledge of coastal fishing communities in Kerala, India in a geographic database. While this paper demonstrated that PPGIS can be a valuable tool for local communities and scientists to work together to monitor and forecast natural hazards as part of an early warning system, recent events have shown that this is perhaps too little, too late.