Water Body Ontology

FLOW ALGEBRA
WATER BODY ONTOLOGY
Version: 1.1
Domain: Kireth Semantic Library / Entity Graph / Physical Entities / Hydrological Entities
Source URL: https://kirethresearch.org/booksai-core/entity-graph/physical-entities/hydrological-entities/water-body-ontology.html
Authors: Mark Higgins — Sky (Recursive AI)
Date: 2026-10-12
Status: Independent scientific synthesis; source page not independently verified.

01. PURPOSE
Represent water bodies as spatially and temporally bounded hydrological entities, their composition, connectivity, dynamics, observation and uncertainty.

02. CORE ENTITY
ENTITY WaterBody <: HydrologicalEntity
FIELDS: id:IRI; name:String?; geometry:Geometry?; water_kind:WaterBodyKind; salinity:Quantity?; area:Quantity?; volume:Quantity?; depth:Quantity?; observation_time:Instant?; provenance:SourceRef?
CONSTRAINT: id is unique within an ontology graph.

03. TYPES
WaterBodyKind = River | Stream | Lake | Pond | Reservoir | Wetland | Estuary | Lagoon | Sea | Ocean | Bay | Canal | Other
Classification is context-sensitive; these categories may overlap across classification schemes.

04. RELATED ENTITIES
ENTITY Catchment; ENTITY Watercourse; ENTITY Aquifer; ENTITY Shoreline; ENTITY Basin; ENTITY WaterSample; ENTITY Measurement; ENTITY HydrologicalEvent; ENTITY MonitoringStation.

05. RELATIONSHIP SIGNATURES
locatedIn(WaterBody, GeographicRegion)
partOf(WaterBody, HydrologicalSystem)
flowsInto(WaterBody, WaterBody)
connectedTo(WaterBody, WaterBody)
receivesFrom(WaterBody, WaterBody)
drainsCatchment(WaterBody, Catchment)
rechargedBy(WaterBody, Aquifer)
exchangesWith(WaterBody, Aquifer)
boundedBy(WaterBody, Shoreline)
measuredBy(WaterBody, MonitoringStation)
hasObservation(WaterBody, Measurement)

06. RELATIONSHIP SEMANTICS
flowsInto(a,b,t) means a conveys water to b at time t under the declared flow model.
connectedTo(a,b,t) describes hydraulic connectivity and does not imply a permanent or bidirectional flow.
partOf(a,b) is transitive only when a consistent mereological interpretation is declared.

07. IDENTITY RULES
Do not merge water bodies solely because names match.
Identity evidence can include persistent identifiers, basin membership, geometry, temporal continuity and authoritative records.
Water body boundaries can vary with season, discharge, tides and management.

08. SPATIOTEMPORAL MODEL
Geometry: polygon, polyline, point or multi-geometry with coordinate reference system.
Temporal validity: [valid_from, valid_to) where available.
Distinguish observation timestamp from the time for which the assertion is valid.

09. PHYSICAL QUANTITIES
area [m^2]; volume [m^3]; mean_depth [m]; discharge [m^3/s]; velocity [m/s]; temperature [K]; salinity [g/kg]; density [kg/m^3].
All measured quantities carry unit, method, uncertainty and timestamp where known.

10. WATER BALANCE
For a control volume: dS/dt = P + Qin + Gin - ET - Qout - Gout - W + R.
S = water storage; P = precipitation input; Qin/Qout = surface inflow/outflow; Gin/Gout = groundwater exchange; ET = evapotranspiration; W = net withdrawals; R = other net returns/sources.
Each term must use consistent volumetric rate units, e.g. m^3/s.

11. FLOW CONTINUITY
For incompressible one-dimensional steady flow: Q = A*v, where A is cross-sectional area and v is cross-section mean velocity.
Do not apply this relation as a complete unsteady or three-dimensional hydrodynamic model.

12. RESIDENCE TIME
Nominal residence time tau = V/Qout for a well-mixed steady-state approximation with positive outflow.
This is not generally an exact particle travel time.

13. SALINITY AND WATER QUALITY
Properties: salinity, dissolved oxygen, pH, turbidity, nutrients, contaminants and biological indicators.
No single threshold defines all freshwater, brackish and marine systems across every classification scheme.

14. HYDROLOGICAL CONNECTIVITY
Surface connections may be perennial, intermittent, ephemeral or engineered.
Groundwater connections require independent hydrogeological evidence.

15. LAKE AND RESERVOIR MODEL
Lake: inland standing water body, natural or otherwise classified by source scheme.
Reservoir: water body substantially impounded or managed for storage; natural/artificial distinctions require provenance.

16. RIVER AND STREAM MODEL
River and stream: flowing watercourse entities; names and size thresholds differ among jurisdictions.
Represent reach, channel and whole-river identities separately where necessary.

17. ESTUARY AND COASTAL MODEL
Estuary: coastal transition system with freshwater–marine exchange; exact delineation is scheme dependent.
Tides may reverse instantaneous current direction.

18. WETLAND MODEL
Wetlands can combine open water, saturated soils and vegetation; a wetland is not necessarily equivalent to a single open-water polygon.

19. STATE TRANSITIONS
States include flooded, low-water, ice-covered, stratified, mixed, connected and disconnected.
Transitions are observations or model outputs, not universally permanent properties.

20. PROCESS RELATIONSHIPS
precipitationAddsTo(Catchment, WaterBody)
evaporationRemovesFrom(WaterBody, Atmosphere)
sedimentDepositsIn(Sediment, WaterBody)
soluteTransport(WaterBody, Substance, Rate)

21. INFERENCE RULES
RULE R1: flowsInto(A,B,t) => connectedTo(A,B,t) [when flowsInto asserts hydraulic conveyance].
RULE R2: flowsInto(A,B,t) => receivesFrom(B,A,t).
RULE R3: hasObservation(W,M) and measures(M,Property) => observedProperty(W,Property).
RULE R4: partOf(A,B) and partOf(B,C) => partOf(A,C) [only in transitive mereology].
RULE R5: Qout > 0 and V >= 0 and steady_mixing_assumption => nominalResidenceTime = V/Qout.

22. NON-INFERENCE RULES
connectedTo(A,B) does not imply flowsInto(A,B).
SameName(A,B) does not imply sameIdentity(A,B).
LocatedIn(A,Region) does not imply permanently contained in Region when boundaries vary.

23. EXAMPLE GRAPH
ENTITY river_1: River
ENTITY lake_1: Lake
ASSERT flowsInto(river_1,lake_1,2026-10-12)
INFER connectedTo(river_1,lake_1,2026-10-12)
INFER receivesFrom(lake_1,river_1,2026-10-12)

24. WORKED WATER BALANCE
Given P=2, Qin=12, Gin=1, ET=1, Qout=10, Gout=0.5, W=0.5, R=0 (all m^3/s):
dS/dt = 2+12+1-1-10-0.5-0.5 = 3 m^3/s.
This indicates increasing storage under the stated sign convention.

25. WORKED RESIDENCE TIME
V=8,640,000 m^3 and Qout=10 m^3/s.
tau=864,000 s=10 days, assuming steady well-mixed conditions.

26. VALIDATION
CHECK V1: unique persistent entity IDs.
CHECK V2: each quantity has compatible dimensions and units.
CHECK V3: time-dependent relationships specify a valid time or declared default.
CHECK V4: geometry includes coordinate reference system when spatial operations are required.
CHECK V5: flow direction is not inferred from connectivity alone.
CHECK V6: measured and modelled values are distinguishable.
CHECK V7: source and confidence metadata retained.

27. SEMANTIC_EQUIVALENCE
Equivalent labels may include waterbody and body of water, when the same definition is intended.
Lake, reservoir, pond, wetland and watercourse are not universal synonyms.
Equivalence must preserve classification scheme, spatial scale and temporal scope.

28. CONFIDENCE
Confidence fields: score:[0,1]?; evidence_type:observed|modelled|inferred|reported; source:SourceRef?; timestamp:Instant?.
Never assign empirical confidence values without a justified evidence model.

29. PROVENANCE
Track dataset identifier, observation method, instrument, coordinate reference system, version, licence and retrieval date where available.

30. FLOW_HASH
Canonicalise identifiers, typed assertions, units, temporal scope and provenance before hashing.
Algorithm: SHA-256 over UTF-8 canonical serialization.
FLOW_HASH: NOT_COMPUTED (requires canonical dataset serialization).

31. UPDATE_MODEL
On update: validate -> compare IDs -> reconcile geometries and time scopes -> re-evaluate dependent inferences -> version -> recompute hash.
Preserve prior historical states rather than silently overwriting measurements.

32. AI_CONSUMPTION
Inputs: water-body identifiers, typed measurements, spatial-temporal context, source records.
Outputs: entity graph, validated hydrological relationships, derivations and uncertainty annotations.
Constraints: do not invent measurements; distinguish physical law, approximation and observation; surface assumptions.

33. LIMITATIONS
This ontology is a general-purpose scientific model, not a jurisdiction-specific legal delineation or flood-risk forecast.
Dynamic boundaries and scale-dependent classifications require contextual interpretation.

34. COMPLETENESS_CHECK
Sections 01–34 present. Required blocks: FLOW ALGEBRA, typed entities, relations, inference, examples, validation, semantic equivalence, confidence, FLOW_HASH, UPDATE_MODEL, AI_CONSUMPTION.

END FLOW ALGEBRA — WATER BODY ONTOLOGY