You say that Lake Okeechobee is the "back up'water source for South Florida. Since there is no aquaduct from South Bay to Miami what must the elevation of the lake be to gravity flow the approximate 80 miles to Miami?
Clue, the slope of a french drain is 1/8″ per foot.
Answer is 4,400 feet.
Lake Okeechobee water is actually pumped from the lake into a series of canals built by the Army Corps of Engineers and maintained by the South Florida Water Management District. Some water also flows into conservation areas and sugarcane plantings, which eventually flow into the Everglades and the Biscayne Aquifer below/
No it’s not! The water in the lake comes from rainfall and the rivers to the north; Kissimee and northwest Fisheating Creek. The water drains from the lake thru the locks that control the access to the lake from the St Lucy Canal and the river that drains the lake west to Ft. Meyers, FL. The S. Florida Water Management District, formerly “Flood Control” was created to try to control flooding after Miami Springs and Hialeah went under water during a few wet and rainy years and not to pump water into lake Okeechobee. The canals are the remnants of an attempt to drain the wet flat geography of S. Florida that failed and caused salt intrusion into the Biscayne Aquifer and later were dammed up to stop it. These canals are used to transport excess water during wet times and the water is stored in the three Conservation Areas and NOT Lake Okeechobee.