South Florida’s southern Everglades, 1850 vs. 2003 similar to 2019. Image courtesy of SFWMD, based on the book Landscapes and Hydrology of the Predrainage Everglades, McVoy, Said, Obeysekera, VanArman, Dreschel, 2011.

Today I share a familiar set of images. Although we have seen many times, they remain mind-blowing. Don’t they?

~Yellow lines outlining Florida’s original Everglades’ River of Grass contrasted to today’s highly human impacted, managed system.

What one may not notice, are the “Transverse Glades” labeled on the lower right area of the Pre-Drainage image? There are two types: “Peat Transverse Glades” and “Marl Transverse Glades.”

So what are they? Or better said, what were they? And what do they mean?

“A Transverse Glade is a surface-shallow groundwater drainage pathway moving water out of the main Everglades Basin and controls the Everglades water table.” (Ogurcak, https://conference.ifas.ufl.edu/GEER2008/Presentation_PDFs/Additions/THURSDAY/Meeder-Thursday-Transverse%20Glades%20Karst.pdf)

These transverse glades would have been moist in the dry season and could be totally inundated during the wet season as they allowed the waters of the Everglades Basin to slowly seep/flow out.

Following Nature’s hand, the first canals built to Lake Okeechobee from the coast were started or ended in these areas. The early settlers used the canals not just for drainage, but also for transportation to and from the Lake and surrounding areas.

The first canals constructed were the North New River Canal  (1906-1912) connecting to today’s  Ft Lauderdale in the area where the peat transverse glades were located; and the Maimi Canal (1910-1913), in the area where the marl transverse glades were located. Both the New River and Maimi River were neighbors of the transverse glades. Makes sense doesn’t it?

Early Post-drainage 1910, Harshberger image, 1913.

Today?

One would never even guess the transverse glades ever existed thinking all the water flowed out of Shark River Slough and Taylor Slough. Not the case when we look back far enough; we can see Mother Nature’s design. Interesting isn’t it?

Facility & Infrastructure Map, SFWMD 2019

Plate 5, Landscapes of the pre-drainage Everglades and bordering areas, ca. 1850. Courtesy: Landscapes and Hydrology of the Predrainage Everglades, McVoy, Said, Obeysekera, VanArman, Dreschel, 2011.

Figure 11.12 Landscapes of the pre-drainage Everglades and bordering areas, ca. 1850. Courtesy: Landscapes and Hydrology of the Predrainage Everglades, McVoy, Said, Obeysekera, VanArman, Dreschel, 2011.

Google Earth 2019

See for explanation of peat and marl soils: https://www.nps.gov/ever/learn/nature/evergeology.htm

See Chapter 10, peat and marl transverse glades: https://www.academia.edu/13200912/Landscapes_and_Hydrology_of_the_Predrainage_Everglades-Overview