What data a municipality needs for GIS-based risk management

A municipal risk GIS is useful when it connects a decision to hazard, exposed elements, vulnerability, capacity and current evidence. Placing maps in a viewer is not enough, and the system does not replace the specialist studies used to establish hazard or risk conditions.

Colombia's Law 1523 of 2012 organises disaster risk management around knowledge, risk reduction and disaster management. The national framework is available through the National Disaster Risk Management Plan. For a municipality, the practical issue is how to turn scattered studies, inventories and reports into records that support priorities, ownership and follow-up.

Define decisions before layers

List recurring decisions: inspect a location, update a scenario, prioritise a mitigation measure, prepare an evacuation route or review the exposure of a facility. For each one, identify the minimum data, accountable owner and acceptable freshness. This prevents the team from building a large database nobody can maintain.

An initial structure usually keeps separate:

• hazards and their scenarios;
• population, buildings, networks and other exposed elements;
• vulnerability and capacity conditions;
• historical events and field reports;
• risk reduction, preparedness and response measures;
• sources, scales, dates, methods and uncertainty.

Do not merge these categories into a single “risk” layer. A hazard zone, an exposed asset and a vulnerability assessment answer different questions.

Preserve scale, date and authority

Record who produced every layer, with which method, at what scale, on which date and for what use. A community report can identify a condition worth inspecting, but it should not be labelled as equivalent to a technical study. Regional cartography should not be presented as parcel-level evidence.

When sources disagree on a boundary or classification, retain both versions and create a review decision. The GIS should expose uncertainty rather than silently changing a value. Cartographic inputs used for territorial risk incorporation need to be checked against the current instrument and applicable rules.

Connect the map to verifiable actions

Every priority finding needs a status, owner, review date and evidence. A useful dashboard distinguishes confirmed, pending and discarded items. Photographs, minutes and measurements link to the spatial object without turning a map colour into an automatic diagnosis.

The GIS for territorial planning and POT is related when findings need to inform planning determinants, layers and monitoring. Risk management and planning nevertheless retain their own products, authorities and procedures.

Test updating, not only visualisation

Select one scenario and rehearse the complete cycle: observation, quality control, technical review, status change, priority and closure. Verify access control, backup, history and use with limited connectivity. A decision should be traceable back to its source.

GeoSAT's GIS for risk management can begin with that bounded case. Acceptance criteria should measure traceability and operational use; they should not promise that software predicts a disaster, certifies a study or removes the need for professional judgement.