Oct 24, 2014

Marl meanderer

A narrated walk through a flooded marl prairie

As the (swamp) water cycle turns

All our staff gages are numbered in “tenths of a foot.”

If we could label them by “habitat type” this is what they might look like instead.

The above animation shows the annual
rise and fall of the water table

The swamp appears to have peaked for the year.

That's not unusual.  By late October water levels are usually on their way down.  This year however the fall peak was not as high as usual.  The hydric pines saw water for three months and the higher mesic pines none at all (other than from direct rain). The long-term trend is for waters to rise shallowly into the hydric and mesic pinelands for around 15 and 3 weeks per year, respectively … usually during late summer and early fall.

D oes that mean a "dry" dry season is in the works?

This years rise of the water table in the swamp was not as high as previous years.  Hydric pines shallowly flooded for three months, but mesic pines remained dry.

Answer: (click read more below.)

Oct 22, 2014

Dwarf and dome

Marl Prairie is still flooded,

And the cypress needles are still green(ish.)

Must be October.

Oct 21, 2014

Dry season outlook?

Last few dry season rain totals have been down.

Will this year's El Niño reverse that trend?

The ENSO index plays an influential role in how much dry season rain falls in south Florida. The above graphs show a comparison of the ENSO index to dry season rain totals from 1950 to present.

Only time will tell.

Oct 20, 2014

How does wet season stack up?

The rainy half of the year is almost through.

How did we measure up to previous wet seasons?

The bar chart above reports wet and dry season rainfall for south Florida from 1980 to present.  The long-term wet season average is 39 inches.  This year's 37 inches (with 10 days to go) is just shy of that mark.  The next six months (starting November 1st) mark the dry season half of the water year.   

The graph above divides the water year into two equal lengths:

May through October (color coded blue) displays the 6-month rain total wet season half of the water year. November through April (color coded red) displays the 6-month rain total for the dry half of the year. As you can see, this year's wet seasons total is down from the previous two years. But it's too early to call it a dry year. Deep drought doesn't typically strike south Florida until the spring. Until then, lower winter evapotranspiration rates and periodic frontal storms can sustain the water table high enough to keep the deeper sloughs, strands and domes wet well into the dry season.

A lingering El Niño may increase winter rain totals, too.

Oct 19, 2014

Structural view

Looking downstream
from the S-78 Ortona Dam

Oct 17, 2014

Turtle and dam riddler

Why did the turtle cross the dam?

The answer is not to get to the other side.

The problem was the step drop
(i.e. ten feet), fencing and high
discharge rate below
This turtle was desperate to get into the water.

Oct 16, 2014

Double source of the S-79

Discharge through the S-79 is controlled by two sources:

Releases from Lake Okeechobee.

The Lake is at its highest point of the summer,
but it could start dropping soon with dry season
air moving in.
And direct rainfall in the East Caloosahatchee Basin.

(See below.)
Rainfall in the East Caloosahatchee Basin
was below average this wet season. Last summer
it was above normal.
Scroll down to view the S-79's recent and historic flow history.

Turtle crossing

I got a turtle-led tour
of the S-78 Ortona Dam

Oct 15, 2014

Deep Caloosahatchee History

Here's a historic view of freshwater flows ...

into the Caloosahatchee Estuary through the S-79

The calendar graph above provides a historical and seasonal view of freshwater discharges into the Caloosahatchee Estuary through the S-79 structure.  The graph reads like a page of a book: years from top to bottom and months of the year from left to right.  The color coding matches the hydrograph a few posts down.   Blue and especially black data points indicate times of high freshwater flow and the orange and especially red data points indicate times of low flow.  Green check marks indicate times when the flow envelop is just right. 

Too much water and the brackish balance becomes too dilute (and also susceptible to harmful algal blooms).  Too little water causes saltwater intrusion to creep in.  Last year sustained a three-month span when freshwater releases were too high, making it the worst year for the estuary since 2005.  This year flows have been largely in check due to cooperative Lake O levels and normal wet season rainfall levels in the east Caloosahatchee Basin.

Discharges through the S-79 comes from those two sources.

See map above.

S-78 Lock and Damn

Also on the Caloosahatchee, just upstream of the S-79.

Here's the dam:

From top to bottom: TOP - Panorama taken while standing on structure looking downstream (left) and upstream (right). MIDDLE - View of structure looking downstream. LEFT - View of structure from downstream side looking east (upstream). RIGHT - Looking downstream (west) while standing on structure.

Here's the lock:

From top to bottom: TOP - View of lock taken from downstream (west) end looking upstream (east). LEFT - View of lock in foreground and dam/spillway in background. RIGHT - View of upstream (and outside) side of lock looking east (downstream).