Cartagena — LEZ, air quality & heat resilience#

Profile owner: Ayuntamiento de Cartagena · LDT-UC-01 · Status: 🟠 skeleton pre-filled

1–2 · Identity, problem & context#

Cartagena's Low Emission Zone must demonstrably improve air quality and urban heat resilience. The city twin simulates and monitors LEZ effects (traffic, emissions, noise, heat hotspots) and — via the LDT — enriches them with regional and cross-site insights that an isolated twin cannot produce.

3 · Objectives & KPIs#

Decided Metrics: gCO₂e per vehicle-km in the pilot corridors; LEZ-related emission-proxy trends; hotspot counts (air, noise, heat); eco-routing uptake.

Needs owner — Ayuntamiento de Cartagena.** Per metric the scheme needs four things, and has none of them: the baseline value and the period it was measured over, the target, the measurement window, and the spatial scope (which corridors). A metric without a baseline cannot evidence improvement, and these feed the PD2 and PD5 KPI sets directly. Where a target is politically sensitive, state a measurement commitment instead of a number — that is still usable; silence is not.

4 · Stakeholders#

City of Cartagena (policy & data), residents & commuters (data-rights holders for movement-related data), Nunsys (platform), LogiNex (emission analytics), ERTICO (mobility standards).

Needs owner — Cartagena.** Confirm the regional and national authorities involved (Región de Murcia; any air-quality or transport competence held above municipal level) and state for each whether it is a data provider, a data recipient, or a regulator with a right of access. The distinction decides whether it appears in the scheme as a participant with an accession agreement or as a recipient under a legal obligation, and the two carry different obligations entirely.

5 · Data needs & sources#

IoT air/noise/heat sensors; mobility feeds; LEZ camera/enforcement data (personal-data alert); weather; LCMM / ISO 23795-1 emission computation inputs.

The signed application names three dynamic source families for this twin: floating car data from municipal fleets and public transport, IoT sensor networks for real-time air quality and noise, and meteorological data with satellite imagery for heat-island analysis. They are ingested through standard connectors (MQTT, JSON, UL) into hybrid storage on the Libelium Iris360 stack with the EU LDT Toolbox, harmonised into FIWARE data models compliant with OASC MIM2 behind an NGSI-LD context broker, and exposed through the data-space layer. (Source: EUTwinLink LDT4SSC WS1 Application Form §1.7, Annex 4 to the Pilot Grant Agreement.)

Needs owner — Cartagena.** The source inventory is the precondition for Data models and Data exchange, and neither block can be completed without it. Per source: format, update frequency, quality or coverage level, level of detail, whether it already exposes NGSI-LD / MIM2, and whether it contains personal data.

The LEZ camera and enforcement feed is the one to answer first. It is the only source in this profile that is both personal data and held under an enforcement power, which means its lawful basis is not consent and the Commons model does not reach it. Until Cartagena states what it is and under which power it is processed, the scheme cannot write a defensible policy for it.

Citizen-related mobility data → GDPR base (PD1) + Commons controls + purpose-bound ODRL policies (enforcement: no re-identification, aggregation floors).
Open tier for public air-quality dashboards; restricted tier for enforcement-related data (city-only).
Cross-site benchmarking with Almelo/Hamburg → licence permitting derived-indicator publication, not raw re-sharing.

7 · Architecture (building blocks used)#

IoT and fleet streams ingested via MQTT/JSON/UL connectors into the city twin — which runs on Libelium Iris360 with the EU LDT Toolbox — and floating car data from municipal fleets and public transport; NGSI-LD broker (MIM2) → EDC + iSHARE extension → listing of open datasets on the Marketplace of the EU LDT Toolbox; identity via organisational wallets; scenario simulation for LEZ what-ifs. (Ingestion, platform and data model as in PD4 v1.0 §4 Table 2, text as in PD4 v0.96, 29 Oct 2026; that row is marked for confirmation by the City of Cartagena.)

Proposed Blocks used: Data models (mobility and air-quality semantics), Data exchange (NGSI-LD subscriptions for dynamic data, batch for historical series), Access & usage policies (aggregation floors, purpose binding), Identity & attestation, Publication & discovery, and Provenance wherever an emission figure is used as policy evidence.

Needs owner — Cartagena + PD3 authors.** Cross-reference the PD3 architecture diagram here rather than redrawing it. This profile should name the blocks and the conditions; PD3 owns the architecture.

8 · Timeline & maturity#

Decided Maturity: the city twin is operational today; the LDT interconnection follows the WP7 plan.

Needs owner — Cartagena, with iLabs.** Milestones, with dates: ITB-S conformance of the first exchange path, first open-tier dataset listed in the marketplace, first cross-site indicator exchanged with Almelo, and the LEZ scenario-simulation service available. Dependencies to state alongside them: the source inventory above, and the baseline policy set sign-off in Access & usage policies, which is due 17 Oct 2026.

9–12 · Value, risks, EU alignment, materials#

Decided Value: evidence-based LEZ policy; citizen-visible air-quality gains; a replicable LEZ playbook — replication being the LDT's primary ambition.

Proposed Risks and mitigations:

Risk	Mitigation
Personal-data exposure in mobility and camera data	aggregation floors and purpose binding as ODRL constraints; enforcement data restricted to the city; no re-identification across every tier
Sensor quality gaps undermining the evidence	quality declared per offering rather than assumed; figures used as policy evidence carry provenance
Attribution — proving the LEZ caused the change	baselines and measurement windows fixed before intervention (see section 3); cross-site comparison with Almelo and Hamburg
Public contestation of LEZ policy	open-tier publication of air-quality data; the observer chatbot as a citizen-facing route into the twin

Decided EU alignment: Green Deal, Ambient Air Quality Directive, ITS Directive.

Needs owner — Cartagena + ERTICO.** ERTICO owes the mobility-standards recommendation (which models and ITS profiles apply) that Data models is waiting on. Cartagena owes confirmation that the attribution risk above is the one it is actually exposed to politically — it is the drafter's reading, not the city's.