Japanese map symbol for a weir

A short barred line across a stream.

Also known as: Suimon mark, Sluice mark

Engineering & technicalMaps & navigationStandard profile

Meanings

Denotes a weir or water gate on a Japanese topographic map.

Officially standardisedVerified fact
Marks a weir or water gate on a GSI topographic sheet.
Contexts: Maps
Officially standardisedVerified fact
Is drawn lighter than a dam, the difference in weight standing for the difference in scale between regulating a stream and impounding a river.
Contexts: Maps

A short line drawn across a stream with a small bar at each end, lighter than the dam it resembles.

Current useModerate confidence: Moderate confidence because the current use is documented in encyclopedic references, but only a single source has been found so far.
IdentityModerate confidence: Moderate confidence because the identity is documented in encyclopedic references, but only a single source has been found so far.
Historical originLow confidence: Low confidence because the historical origin is documented in encyclopedic references, but only a single source has been found so far, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Visual matchModerate confidence: Moderate confidence because the visual match is documented in encyclopedic references, but only a single source has been found so far.

Map symbols used on Japanese topographic maps
Geospatial Information Authority of Japan (GSI) · retrieved 2026-08-23
Japan's national mapping agency's own published legend. Cited for the form and meaning of a symbol on Japanese topographic maps; the historical origin of individual symbols is cited separately where claimed.

Last reviewed 2026-08-26

Meanings

Denotes a weir or water gate on a Japanese topographic map.

Officially standardisedVerified fact

Marks a weir or water gate on a GSI topographic sheet.

Contexts: Maps

Officially standardisedVerified fact

Is drawn lighter than a dam, the difference in weight standing for the difference in scale between regulating a stream and impounding a river.

Contexts: Maps

Confidence

Current useModerate confidence: Moderate confidence because the current use is documented in encyclopedic references, but only a single source has been found so far.
IdentityModerate confidence: Moderate confidence because the identity is documented in encyclopedic references, but only a single source has been found so far.
Historical originLow confidence: Low confidence because the historical origin is documented in encyclopedic references, but only a single source has been found so far, but early or supporting evidence is limited, but the regional or cultural match to this specific claim is not precise.
Visual matchModerate confidence: Moderate confidence because the visual match is documented in encyclopedic references, but only a single source has been found so far.

Sources

Map symbols used on Japanese topographic maps
Geospatial Information Authority of Japan (GSI) · retrieved 2026-08-23
Japan's national mapping agency's own published legend. Cited for the form and meaning of a symbol on Japanese topographic maps; the historical origin of individual symbols is cited separately where claimed.

Last reviewed 2026-08-26