BISCAYNE Biscayne National Monument A Proposal

The upper Florida Keys are a chain of narrow islands that separate Biscayne Bay from the Atlantic Ocean. They lie three to seven miles off the Florida mainland south of Miami, and generally consist of an outer barrier of coral limestone on the ocean side and sheltering mangrove swamps on the inner side. A nearly flat sheet of limestone, without appreciable change of slope and with little trace of wave scarp, lies beneath the sea on the ocean side of the Keys. At most places, shoal water extends several miles and then the underlying sheet slopes abruptly to greater depths. Living coral reefs partly cover these shoals.

A bulkhead line has been established along the Keys. This is a line fixed by local authorities and trustees of the Internal Improvement Fund, an instrumentality of the state of Florida. Shoreward of this line, filling is permitted; seaward, it is not. Dredging and filling within the present established limits would permit an almost doubling of the present land area of the upper Florida Keys. Such excessive underwater disturbance would greatly damage natural values.

The proposed National Monument is located south of Miami and is accessible only by boat. It includes a portion of the upper Florida Keys, together with portions of the adjoining waters and bottoms of the Atlantic Ocean and Biscayne Bay.