29/11/2025 –, Audition Room - 1st Floor Langue: English
In humanitarian, disaster, crisis, and many further contexts, timely, accurate and relevant geospatial information is often unavailable, outdated, or misaligned with on-the-ground realities. Latest technological developments and data-driven concepts are enabling us to capture the world in unprecedented detail- with ever-growing volumes of data, promising greater resolution and coverage. But can we truly trust global models that lack local insight?
Research and real-world project examples from around the globe send a clear message: when communities on the ground are not involved, estimates, assessments, and decisions often miss the mark. This can lead to misguided — and sometimes even harmful — outcomes, with serious consequences for the very people and landscapes affected.
So why not turn to those who know the terrain best? Local insights and validation isn’t optional — it’s essential. And the good news? There are practical tools and approaches that make it easy to involve local communities in meaningful ways.
One of them is the Sketch Map Tool (SMT): an open-source web application developed by the Heidelberg Institute for Geoinformation Technology (HeiGIT) and the GIScience Research Group at Heidelberg University to bridge the gap between expert geospatial analysis and community-based knowledge. Driven by the aim to develop a low-tech approach to capture local insights, that does not require previous training or tech knowledge and equipment, apart from map reading and access to a phone or camera.
SMT offers a low-barrier, intuitive platform for communities, NGOs, and responders to express local knowledge, risks, needs, and perceptions through freehand sketching — even in places where formal mapping data is sparse or incomplete.
Inspired by and building on fieldpapers, it allows users to draw spatial information directly onto a paper map using pens, to then scan or photograph the marked Sketch Maps, upload the pic/scan to the SMT website and download the pen drawn markings of the Sketch Maps in different geodata formats (raster data as GeoTIFF, vector data as a GeoJSON file). Through the use of paper maps, accessibility is enhanced and engagement is possible even in offline or analogue settings. This access is further supported through the multi-lingual setup of the SMT website, which currently contains German, English, French, Spanish and Czech, with more languages being planned.
Beyond capturing tangible features like buildings, roads, waterbodies or landmarks, SMT also enables the collection of soft or intangible data — such as community concerns, perceived risks, flood-prone areas, informal settlements, and community assets or locally relevant landmarks — that are again mainly missing from conventional datasets. These maps, therefore, serve not only as a tool for data collection but also support participatory discussion processes that drive inclusion and empowerment.
What role does Open Street Map play for the SMT?
When the Sketch Maps are generated by users, they can choose from a variety of basemaps, including OpenStreetMap (OSM), satellite imagery, or other custom layers. As these base maps serve as orientation, the better and more detailed the base map, the better and more accurate marking with pens can be.
SMT is integrated with the ohsome (OpenStreetMap History Analytics) dashboard, enabling users to visualise OSM data coverage and quality over time for specific regions. When a user selects an area of interest in SMT, it is automatically transferred to the ohsome dashboard, where an analysis of the completeness and recency of data in that area is performed. All analysis parameters can be adjusted to suit the specific use case.
This integration provides valuable insights into the suitability of OSM base map data for field data collection, helps identify existing data gaps, and supports targeted mapping efforts to improve data quality. Such analysis is crucial for ensuring reliable map-based orientation in the field, as outdated or incomplete map data can lead to misorientation, which in turn can negatively impact the accuracy of collected field data.
In previous use cases, these insights have helped ensure that the OSM database is improved directly by local communities or by organising mapping events such as mapathons to engage additional contributors.
And how does AI support the SMT users?
HeiGIT is making use of AI-based feature detection to support automatic recognition and digitisation of drawn features. Machine learning models are utilised to interpret both hand-drawn maps and scanned paper sketches, converting them into structured geospatial data while preserving the original community input. The models have been improved and trained with thousands of Sketch Maps to ensure that the drawings are captured as realistically as possible.
This fusion of low-tech data collection with high-tech processing empowers local actors without placing technical demands on them. The Sketch Map Tool is further publicly available at https://sketchmaptool.heigit.org and is designed to function well even in low-bandwidth or offline environments.
What other developments are down the line?
Capturing local data and ensuring that community insights are collected sustainably — without reliance on external data providers — requires bottom-up approaches.
In this spirit, SMT will soon integrate OpenAerialMap (OAM), enabling the use of recent satellite and, importantly, drone imagery as background layers for sketching. This integration allows users to upload their drone imagery to OAM and access it directly within SMT, supporting more detailed, timely, and locally targeted mapping efforts.
As development continues, we invite the OSM Africa and humanitarian mapping communities to test, contribute to, and collaborate on real-world applications of SMT. We especially welcome partnerships with local mapping groups, Red Cross and Red Crescent societies, and anticipatory action actors working in climate-vulnerable regions.
What can participants expect during the workshop?
The Sketch Map Tool demonstrates the power of pairing inclusive, analogue-friendly community engagement with the latest advances in AI and geospatial technology. By enabling local actors to capture what they know, see, and experience — and by supporting them with powerful analytics behind the scenes — SMT fosters more relevant, representative, and timely geospatial information. It empowers communities to make their voices visible and ensures that their insights inform real-world decisions in humanitarian and development contexts.
We look forward to sharing this work with an intro talk followed by step-by-step walkthroughs using real-world examples of previous and current SMT users, from humanitarian, risk and vulnerability mapping to mapping of cultural landmarks, and enabling participants to directly conduct the steps themselves.
We would love to have this opportunity to enable us to learn about the ideas and challenges of the community and strengthen collaboration with the OpenStreetMap Africa network.
Melanie Eckle-Elze is an experienced OpenStreetMap (OSM) contributor, humanitarian mapper, and Research Assistant at the Heidelberg Institute for Geoinformation Technology (HeiGIT). In her role focused on Partner Engagement, she connects research, operational partners, and the open data community to support humanitarian and development efforts through geospatial innovation.
Melanie began mapping in 2012 and discovered her passion for humanitarian mapping while working with Kathmandu Living Labs in Nepal in 2013. She co-founded disastermappers heidelberg and has since organized numerous mapathons and workshops to promote open mapping and disaster preparedness.
She is the Product Owner of the Sketch Map Tool, Missing Maps focal point at HeiGIT, and focal point for the IFRC GIS Training Platform, where she supports capacity building and knowledge exchange with Red Cross and Red Crescent Societies. Her work focuses on the use and creation of open data with a strong focus on OSM data and applied geoinformation systems for disaster management, anticipatory action, and humanitarian response.
Melanie is particularly interested in participatory and locally led mapping approaches, ensuring communities are not just mapped but actively involved in the process. She served on the HOT Board of Directors (2018–2019) and continues to support open, inclusive, and impactful mapping.