Water Boundaries - Practical Boundary Surveying - page 197

Fig. 13.1 Property bordering a stream is presumed to go to the center or thread of the stream
average high water (Fig. 13.1 ). The presumption of owning to the stream thread
applies if the deed merely calls for the stream in general terms, as a boundary.
For example if a deed said that the property ran along Whiskey Creek or Angela
Brook, the owner would be presumed to own to the thread of the stream. A deed
may have words of exclusion, providing that the ownership only runs to the edge
of the stream. For example, if a deed says that the line runs to the high water mark
of Gold Creek, the upland owner would not own the bed of the stream. The thread
of a stream should not be confused with the channel or deepest part of a stream,
sometimes called the Thalweg .
Where a stream is non-navigable, the upland owner bordering on one side of
the stream is presumed to own to the middle or Thread of the stream.
Along navigable tidal waters such as the ocean shore or tidal rivers, the upland
owner does not own the bed. Under federal law, ownership extends only to Mean
High Water . Mean high water is determined by calculating average tidal heights for
a period of 18.6 years. Although the tide is affected by both the sun and the moon,
the moon has the greatest effect. The 18.6 year period is the time required for the
declination of the moon to complete one cycle. The Federal Government maintains