WATER COURSE - This term is applied
to the flow or movement of the water in rivers, creeks,
and other streams.
In a legal sense, property In a water course is comprehended
under the general name of land; so that a grant of
land conveys to the grantee not only fields, meadows,
and the like, but also all the rivers and streams,
which naturally pass over the surface of the land.
Those who own land bounding upon a water course,
are denominated by the civilians riparian proprietors,
and this convenient term has been adopted by judges
and writers on the common law.
Every proprietor of lands on the banks of a river
has naturally an equal right to the use of the water
which flows in the stream adjacent to his lands, as
it was wont to run (currere solebat) without diminution
or alteration.
No proprietor has a right to use the water to the
prejudice of other proprietors, above or below him,
unless he has a prior right to divert it, or a title
to some exclusive enjoyment. He has no property in
the water itself, but a simple usufruct as it passes
along. Agua currit et debet currere, is the language
of the law.
Though he may use the water while it runs over his
lands, he cannot unreasonably detain it or give it
another direction, and he must return it to its ordinary
channel when it leaves his estate. Without the consent
of the adjoining proprietors, he cannot divert or
diminish the quantity of the water, which would otherwise
descend to the proprietor below, nor throw the water
back upon the proprietor above, without a grant, or
an uninterrupted enjoyment of twenty years, which
is evidence of it.
When there are two opposite riparian proprietors,
each owns that portion of the bed of the river which
is adjoining his land usque ad filum aquae; or, in
other words, to the thread or central line of the
stream and if hydraulic works be erected on both banks,
each is entitled to an equal share of the water.
The water can only be used by each as an entire stream,
in its natural channel; for of the property in the
water there can be no severance.
But it seems that when an island is on the side of
a river, so as to give the riparian owner on that
side one-fourth of the water, the other is entitled
to the whole of the three-fourths of the river.
