事例1：パイプライン事故、第5巡回区（50/50分割）
A dredging contractor damaged a subsea pipeline after surveyors mis-marked its location. The Fifth Circuit ruled that both the surveyors (who misrepresented the pipeline's position) and the pipeline operator (who failed to independently verify) shared liability —50/50. The case established that coordinate errors in utility-marking surveys create joint liability between the survey firm and the infrastructure owner.
Root cause: incorrect datum or transformation in the survey that misplaced the pipeline marker relative to its true position.
事例2：Precision Pipeline v. Trico Surveying (W.D. Pa. 2016)
A pipeline contractor alleged that alignment drawings negligently omitted subsurface crossings, causing unforeseen excavation costs on a gas pipeline project. The claim was framed as negligent misrepresentation —surveyors delivered alignment sheets that implied completeness and accuracy, but failed to depict all relevant subsurface features at the correct positions.
Financial stakes: construction delay and rework costs on a major pipeline project, with litigation in the Western District of Pennsylvania federal court.
事例3：FEMA洪水地図BFE詐欺（ミズーリ州）
Homeowners in Missouri alleged that engineers and contractors "fraudulently" changed a flood map's Base Flood Elevation by approximately 34 feet, affecting whether their properties fell within Special Flood Hazard Areas. The investigation centered on vertical datum manipulation, whether the BFE was expressed in NAVD88 or NGVD29 without disclosure, effectively reclassifying properties.
Consequence: property value destruction, mandatory flood insurance requirements, and ongoing litigation over misrepresentation of vertical datum reference.
事例4：FAA UAS空域座標の執行措置
The FAA's 2024 enforcement policy shift makes legal action the default for UAS operations in wrong coordinates or restricted airspace. Civil penalties range from $1,700 to $36,000 per violation, with certificate revocation possible for repeat offenders. The triggering error is a geofencing or coordinate-based airspace representation that places the drone outside its actual operated zone.
High-exposure scenario: a mapping firm conducts corridor surveys and their drone GIS software uses a different datum than the FAA Class B airspace boundary definition, the drone crosses the boundary without the operator realizing.
事例5：FEMA洪水区域の誤分類（全米）
ProPublica documented that FEMA has used outdated elevation data placing homeowners in incorrect flood-risk zones. When vertical datum errors (NGVD29 vs NAVD88) cause a property's structure elevation to appear above or below the BFE, the financial impact includes excess premium payments, forced insurance purchase, and property valuation disputes. Correction requires a Letter of Map Amendment (LOMA) —a technical process costing $500, 5,000 per property.