Definition
Jus aquam ducendi (Latin: "the right of leading water") is a Roman-derived servitude — a right appurtenant to land — entitling its holder to conduct water across another person's land. In English legal tradition, the term appears in early medieval sources as one of several recognized easements relating to water use. It is the affirmative right to construct and maintain a channel, pipe, aqueduct, or similar conveyance across a neighbor's property for the purpose of delivering water to the dominant tenement.
The right is a species of easement rather than ownership of the water itself. The servient landowner retains title to the land burdened by the right; the dominant owner holds only the privilege of passage for water.
Common Confusion
Jus aquam ducendi is sometimes conflated with the related Roman concept aquae ductus, which refers to the physical infrastructure — the aqueduct or channel — as well as to the servitude permitting its use. The distinction matters in historical sources: aquae ductus tends to appear in discussions of the physical works and the general category of water servitudes, while jus aquam ducendi specifically names the legal right of conveyance. Burrill's own entry directs the reader to aquae ductus for fuller treatment, suggesting the terms were used interchangeably in English legal practice even where Roman law had distinguished them more carefully.
Researchers should also distinguish jus aquam ducendi from jus aquae haustus (the right to draw water from a neighbor's source) and jus aquae immittendae (the right to discharge water onto another's land). These are related but distinct servitudes, each conferring a different type of entitlement.
Why It Matters in Research
This term belongs to a cluster of Latin water-rights terminology drawn from Roman civil law and carried into English legal writing primarily through the medieval treatise tradition. Several navigational points are critical:
First, the term is essentially extinct in modern common law practice. Contemporary water rights and easement law does not use this phrase; a researcher encountering jus aquam ducendi will almost always be working in pre-modern English sources — Bracton, Fleta, and their successors — or in comparative civil law materials.
Second, the Fleta citation (lib. 4, c. 18, § 3) is the primary anchoring source in the English tradition. Fleta, the late thirteenth-century English legal treatise, adapted Roman law concepts into the English common law framework. When this term appears in historical sources, it is usually traceable to that tradition rather than to independent English development.
Third, the practical scope of this right in historical English law is narrower than its Roman counterpart might suggest. Roman aquae ductus was a formally codified servitude with detailed rules governing width, maintenance, and compensation. English medieval sources borrowed the terminology but did not always import the full Roman doctrinal apparatus. Researchers should not assume that citations to jus aquam ducendi in English sources carry all the implications of the Roman civil law version.
Fourth, in the Law Mind corpus, this term connects primarily to easement and servitude materials and to historical water law. If a document uses this phrase, it signals engagement with the civilian or learned-law tradition rather than purely indigenous common law development.
Historical Dictionary Support
Burrill's Law Dictionary provides the sole historical dictionary treatment in the available sources. Burrill's entry is terse — as his Latin maxim entries typically are — identifying the term as old English law, glossing it as "the right of leading water (over another's land)," and directing the reader to the Fleta citation and the cross-entry at aquae ductus. The entry is accurate as far as it goes, but it offers no substantive analysis of the right's scope, how it was acquired or lost, or how it compared to parallel common law easements of way or water.
What Burrill does not address — and what researchers should note — is the mechanism by which this Roman-derived servitude was integrated into English law. The civilian framing of Fleta was not always comfortable in a common law court, and the practical enforcement of water-leading rights in medieval and early modern England tended to proceed through common law easement doctrine rather than through the Roman servitude framework, even when the Latin terminology was preserved in learned writing.
No other historical dictionary in the standard Law Mind shelf treats this term independently; it is treated as a sub-entry or cross-reference under water rights and easement headings elsewhere.
Jurisdictional Note
This term has no operative significance in modern American or English law as a distinct legal category. It survives only in historical and comparative contexts. Civil law jurisdictions with Roman-derived property law (Scotland, Louisiana, Quebec, South Africa) maintain analogous servitude concepts under different terminology, but jus aquam ducendi itself is not a term of art in those systems' modern practice.