INPUT LEDGER
What is known, entered, or assumed.
| Input | Value | Origin |
|---|---|---|
| Fishing reach | No on-site public gauge | Missing direct observation |
| Candidate gauge | 18 km downstream | Illustrative spatial match |
| Network relation | Same named river, tributaries in between | Illustrative network context |
| Observed value | Available at the gauge only | USGS observation |
REPRODUCIBLE CALCULATION
Follow the intermediate result.
Distance screen
Formula or rule: Gauge is geographically near
Result: Potential proxy
Network screen
Formula or rule: Check same flow path and intervening tributaries
Result: Not equivalent conditions
Display rule
Formula or rule: Attach gauge name, time, and distance
Result: Label as nearby observation
Decision rule
Formula or rule: Use trend cautiously; verify local alerts
Result: No exact reach claim
DECISION READING
What the result means.
The observation may provide directional context, especially for trend, but it must remain attached to its actual gauge. FINVECTOR should never relabel the measurement as if it came from the fishing reach.
SENSITIVITY
What could change the answer.
- Tributaries, dams, withdrawals, and rain cells can weaken the proxy.
- Older timestamps reduce usefulness even when the gauge is close.
- A matched hydrologic network is stronger evidence than straight-line distance alone.
BOUNDARIES
What this case does not prove.
- The 18 km scenario is illustrative and not a live water report.
- Gauge observations do not establish safe wading, boating, or access.
- Users should review current agency alerts and local conditions.
OFFICIAL SOURCES
Where factual context is verified.
RELATED FINVECTOR CASES
Change one assumption and compare again.
Each case keeps inputs, arithmetic, evidence, and uncertainty in separate layers.