Overview#
When a utility loses power, water, or gas at a point on the network, the urgent question is always the same: which zones and which critical facilities have just gone dark, and who needs to be dispatched. This capability answers that question instantly and precisely, replacing manual map lookups and phone trees with a spatial calculation that runs the moment an outage is reported.
GIS Zone Hierarchy models an operator's entire service geography as a structured three-tier hierarchy: supply zones at the top, distribution zones and District Metered Areas beneath them, and individual physical facilities such as water treatment plants, pump stations, reservoirs, substations, switching stations, and gas regulators at the base. Zone boundaries are held as standards-compliant geographic polygons, so when an outage location and affected radius arrive, a spatial intersection across every active boundary returns the complete, tier-partitioned list of impacted zones in a single pass. That scope then drives downstream work: work orders are raised for affected critical facilities and restoration estimates are calculated as soon as the impact is known, compressing the time from detection to crew dispatch.
Key Features#
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Three-Tier Zone Hierarchy: A self-referential parent-child structure models supply zones (Tier 1), distribution zones and District Metered Areas (Tier 2), and physical facilities (Tier 3). Facility types are first-class and include water treatment plants, pumping stations, reservoirs, substations, switching stations, and gas regulators, so the model reflects how real utility networks are actually organised.
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Polygon Zone Boundaries: Each zone carries a geographic boundary polygon in the WGS-84 coordinate reference system. Boundaries are accepted and returned as standard geographic data, making it straightforward to round-trip zone geometry between mapping clients, enterprise GIS platforms, and the hierarchy.
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Recursive Tree Traversal: The full hierarchy is walked with a recursive common table expression that returns a depth-ordered, flat representation of any subtree. Callers can request the entire organisation tree or start from a single node, getting every descendant in one response without iterative round trips.
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Spatial Outage Scope Resolution: Given an outage centre and an affected radius in metres, a single geospatial predicate finds every active zone boundary within range, using metre-accurate distance maths on the geography type. Results are partitioned by tier so operators immediately see how many supply zones, distribution zones, and facilities are affected.
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Downstream Workflow Activation: As soon as a scope is resolved, the capability raises work orders for the critical facilities inside the impacted area and kicks off restoration estimate calculation. The path from outage detection to crew dispatch is automated rather than handled by manual hand-offs.
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Real-Time Scope Broadcast: A live subscription pushes scope changes over WebSocket to connected dashboards and clients the instant a calculation completes, so control-room views stay accurate without polling.
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Cross-Connector Zone Fusion: Geospatially adjacent zones imported from different external GIS systems are reconciled automatically. A proximity bounding-box criterion links co-located zones from separate source systems into a single coherent model with a recorded confidence score, so an operator running multiple GIS platforms sees one unified geography.
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Multi-Tenant Isolation and Audit: Every zone and every scope is scoped to an organisation, and every change is written to an audit trail. Operators share infrastructure without ever seeing each other's geography, and each mutation is fully accountable.
Use Cases#
Electricity Network Operators#
Model high-voltage distribution zones, medium-voltage circuits, substations, and switching stations as a single hierarchy. When a fault is reported, instantly see which substations and circuits fall inside the affected radius and dispatch crews against a precise list rather than an educated guess.
Water Utilities#
Represent supply zones, District Metered Areas, treatment plants, pumping stations, and reservoirs as connected tiers. A burst main or pressure event resolves immediately to the affected DMAs and the treatment and pumping assets that serve them, supporting faster isolation and restoration.
Gas Distribution#
Map supply and distribution zones down to individual gas regulators. A reported incident returns the exact set of regulators and zones within range, helping field teams prioritise safety-critical assets first.
Multi-System GIS Integrators#
Organisations consolidating several geographic source systems, such as enterprise GIS territories, operational technology feeders, and customer information system territories, benefit from automatic fusion that links co-located zones from different connectors into one model, removing duplicate and conflicting geography.
Control-Room and Dispatch Teams#
Live scope broadcasts keep situational displays current as outages evolve, giving dispatchers and supervisors a continuously accurate picture of network impact without manual refresh.
Integration#
The hierarchy is exposed through a GraphQL service. Read endpoints return zone listings, the depth-ordered hierarchy tree, and any previously computed outage scope. The core operational endpoint resolves an outage scope from a location and radius and returns the affected zone identifiers partitioned by tier, while a live subscription streams scope updates to clients over WebSocket as calculations complete.
All access is protected by OAuth2 with JWT bearer tokens, and every request is automatically scoped to the caller's organisation, so tenants are isolated by construction. Zone boundaries are exchanged as geographic polygon data on input and output, which means a customer can plug in geometry exported from their existing GIS platform and read it back in the same widely supported form. External GIS connectors, including ArcGIS feeds, can be ingested directly, and the fusion process reconciles their geography against zones already in the model. REST and webhook-based connectors round out the picture for systems that publish outage events or consume the resulting scope, and the normalised zone and scope models give every integrating system one consistent shape to work with regardless of source.
The benefit for a customer is concrete: connect your authoritative GIS, point outage events at one endpoint, and receive a precise, tier-structured impact answer plus automatically raised work orders and restoration estimates, all without building the spatial maths yourself.
Open Standards#
- GeoJSON (RFC 7946): Zone boundary polygons are accepted and emitted as GeoJSON, parsed and serialised through standard PostGIS geometry conversion functions, so geography interoperates cleanly with mapping libraries and enterprise GIS exports.
- WGS-84 (EPSG:4326): All spatial geometry uses the WGS-84 geographic coordinate reference system, the global default for latitude and longitude, and metre-accurate distance calculations are performed on the geography type derived from it.
- PostGIS / ISO SQL/MM Spatial: Spatial predicates follow the ISO SQL/MM Spatial standard as implemented by PostGIS, including within-distance, containment, point construction, and reference-system assignment operations, giving customers a well-documented and portable spatial foundation.
- OAuth2 and JWT (RFC 6749 / RFC 7519): Authentication and authorisation use OAuth2 flows with signed JWT bearer tokens, the standard for securing modern service endpoints.
- GraphQL: The read, write, and live subscription surface is published as a GraphQL schema, giving consumers a typed, self-describing contract over the hierarchy and scope model.
- WebSocket (RFC 6455): Live scope updates are delivered over the WebSocket protocol, the open standard for bidirectional real-time messaging to browsers and clients.
Security & Compliance#
Every zone, scope, and fusion link is isolated by organisation, so multi-tenant deployments guarantee that one operator can never read or alter another's geography. All endpoints require an authenticated, authorised caller, and access to the hierarchy is further gated by role and clearance checks before any zone data is returned. Each create, update, delete, and scope-resolution operation writes an immutable audit record capturing the actor, the organisation, and the affected records, giving operators a complete and accountable history of how their network model and outage scopes have changed over time.
Last Reviewed: 2026-05-26 Last Updated: 2026-05-26