FLORIDA GEOLOGICAL SURVEY
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Figure 11. Monthly variation in sea level for the contiguous United States (after
Marmner, 1951).
dimension of a measure of beach change, it agency. The results of this paper provide a does serve to straightforwardly punctuate quantitative basis upon which to inform the the nature of the phenomenon. The manner public, and a method to assess a permit of approaching quantification of the application. phenomenon here, allows for a simply applied methodology that is useful for Seaward Boundary of Public educational, technical, and planning versus purposes. Private Ownership
General Knowledge The boundary between private (i.e., upland) and public (i.e., seaward) beach Seasonal beach shifts are not ownership is fixed by some commonly generally known by the layman. In Florida, applied tidal datum. For most of the U. S. with 35,000 new residents arriving monthly this is the plane of mean high water (MHW) (Shoemyen and others, 1988), new coastal which, when it intersects the beach or coast property owners have been alarmed after forms, the mean high water line. However, purchasing ocean-fronting property during unlike other riparian ownership the "summer" when their beach is wide, to determinations (i.e., fluvial, lacustrine and find or return to find a narrow "winter" estuarine), littoral properties must, in beach, believing that they have unwittingly addition, contend with significant wave purchased eroding property. Ostensibly, this activity that seasonally varies. Hence, might result in an application for a permit to ocean-fronting beaches all-too-often construct a coastal hardening structure such experience cyclic seasonal width changes of as a bulkhead or seawall without a magnitude long recognized as problematic investigating seasonal beach width variation in affixing an equitable boundary (Nunez, on the part of the applicant, the applicant's 1966; Johnson, 1971; Hull, 1978; O'Brien, design professional, or the permitting
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