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Intro - Self-organizing water

"No basin is an island, but is rather (like Florida) a peninsula connected to the main." Almost said (and probably thought) by Henry David Thoreau.

By Robert V. Sobczak

Mention the name Florida and people probably instinctively think “the sunshine state.” But is there a state where water is more abundant and more central to how we think of the place? And I’m not talking the Atlantic or Gulf coasts, although you can add those in too. I’m talking about Florida’s 30 major basins, 5 major water management districts, 4 national estuary programs and 3 major aquifer systems.

Major rivers and watersheds of the United States

The same goes for the other major watersheds across the continental united states. No watershed is an island, they are connected to the greater whole. Oh, and all watersheds have their own water cycles. It is our watersheds on the ground, below ground and up in the sky that connect us all.

Recent Blog Posts

Mid summer soliloquy
Origin story of a hydrologist

When exactly does a hydrologist …

Become a hydrologist?

Bob explains his origin story

In this video, I dive deep into my past to try to figure it out. What I learned? While there was possibly one magical moment “when it all clicked,” it was as much a gradual process as it was instant success. As for my greatest hydrologic achievement. While many may say Go Hydrology, I am very confident that moment has yet to come, and — if it shapes up like I hope it will — it will be nothing short of a total reinvention of the water wheel. Hint: Think sundial meets and an underground cloud.

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Question: Everyone has some hydrologist in them. What’s your water origin story?

My brother (right) introduced me to water. My first boss Dom (left) taught me how to mix water to make mud (i.e. liquid cement) for laying brick and block.

animation lake canoe

Caloosahatchee meets Mississippi
And how the two compare

The Caloosahatchee is …

The king of freshwater flows in South Florida.

Comparison of annual freshwater discharge from the Caloosahatchee (red), Apalachicola (dark green) and Mississippi River (light green)

Currently flowing at around 5,000 cubic feet per second (cfs), it’s the single highest flowing point in the Greater Everglades. But not only is that flow rate dwarfed by the 17,000 cfs discharging out the mainstem of north Florida’s Apalachicola River, both are dwarfed by the nearly 700,000 cfs discharging from the Mississippi River into the Gulf. How much is 700,000 cfs … in more relatable lay audience terms? Answer: Every year, on average, the Mississippi River discharges about 100 Lake Okeechobee’s worth of freshwater into the Gulf. Note: The calculation is based on the assumption of a Lake stand of 15 ft above seas level, or the top of the Lake’s interior-levee littoral zone at which time its water volume is around 4 million acre feet. On average, the Caloosahatchee discharges about a quarter Lake Okeechobee volume worth of freshwater into the Gulf per year. Of course in the case of both, it’s just not water quantity — water quality matters, too, if not the most.

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Tidbit: The Mississippi starts its 2,552 mile journey to the Gulf of Mexico at Minnesota’s Lake Itasca, as photographed in 2014.

Watersheds of south Florida

Major Rivers of the US
And the watersheds that feed them

Watersheds famously …

Don’t obey jurisdictional lines.

Major Rivers and Watersheds of the United States

The reason? For one, most (or many) jurisdictional lines are straight whereas watersheds and rivers — at least in their natural state — abhor straight lines. Many a squiggly state line actually follow along the path of a river. The top of Kentucky, the bottom of Indiana and Ohio and the side of West Virginia are each formed by the Ohio River. Probably most famous in that regard is the southern boundary of Texas, as delineated by the Rio Grande. Mexico and Texas aren’t so much separated by the river as they are united by the Rio Grande Watershed (orange). The same principle applies on the northern boundary with the Red River. It flows north into Lake Winnepeg which is part of the larger Saskatchewan Basin that flows into St. James Bay.

Morale of the Story: Rivers and watersheds go hand in hand, and yes, they will cross over jurisdictional lines.

Floodplain features
Working river returns to nature

Hiking the Gunpowder River …

is a study in floodplain dynamics.

Cross section of the Gunpowder River Valley

Not just a single or simple valley that the stream sometimes overtops, a hike along the trail is a living textbook on the many features and geomorphic processes in action. Rapids for example usually occur where larger rock outcrops are visible on the hillside. And it’s not just a single channel. Also periodically present are yazoo tributaries, oxbow lakes, backswamps made soggier by logjam pools and dry meander scars that the river once cut out. But maybe my favorite feature is the older terraces that form a stairstep from the modern-day floodplain to the adjacent hillside. Today, the terraces are home to very large trees. So they haven’t flooded for quite some time. But how long? Was it a feature from the higher flow rates experienced in the waning days of the last ice age? Or has upstream Pretty Boy and Loch Raven Dams reduced river flows below a point that water makes it up onto that second step?

Another feature I didn’t show was the many archaeological remnants from the pioneer days. They too leave me to wonder: Today, the corridor is a nature preserve, but for the original settlers, it was a working river that powered many a mill.


Chesapeake Bay Watershed
And how it compares to Lake O

How big is Chesapeake Bay …

Or more importantly, its watershed?

Map of the Chesapeake Bay Watershed

The Chesapeake Bay watershed comprises 64,000 square miles, encompasses six states including Maryland, Pennsylvania, Virginia, Delaware, New York, West Virginia and all of the District of Columbia. The land-to-water ratio of 14:1 is the largest of any coastal water body in the world. But how big is all that in Lake Okeechobee units? Excellent question!

Answer: The Chesapeake Bay Watershed is 88 times the size of Florida’s Lake Okeechobee and the bay itself is six times the size of Lake Okeechobee. I know what you’re thinking: That’s an unfair comparison, i.e. what happens when you throw in Lake Okeechobee’s upstream watershed (including the Kissimmee River Valley, Fisheating Creek, Lake Istokpoga and a few more)? Even then the Chesapeake is a lot bigger — 13 times bigger than Lake O and all its upstream watersheds.

I‘m not saying the Lake isn’t big, all I’m saying is it makes a good measuring cup.