Tag Archives: understanding acre feet

Comparing Discharges: Caloosahatchee to the St Lucie 2010-2019

“Destruction by the Numbers,” 2

S-79 Spillway Caloosahatchee at Franklin Lock and Dam, Calendar Year 2010-2019, courtesy http://eyeonlakeo.com, Todd Thurlow.
Structures along the Caloosahatchee River, courtesy Melody Hunt, Research Gate. S-79 is the gate used for purposes of this post. S-79 is comparable to the St Lucie’s S-80 at St Lucie Locks and Dam, in that it is the final structure along a channelized river thus allowing both runoff from the surrounding “basin” and water discharged from Lake Okeechobee.

Last week, I presented a blog on discharges, 2010-2019, to the St Lucie River from both the surrounding basin, and Lake Okeechobee. Although we can separate Lake O’s numbers, it is important to know just how much water, thus sediment, nitrogen and phosphorus, the estuaries are taking “at once.” I have often said the worst thing about discharges from Lake Okeechobee is that the river is already on life support -from being drowned out by basin runoff- when Lake Okeechobee is leashed open.

So called “basins” around our rivers, like everything else in South Florida,  have been altered to drain more efficiently than Nature intended. Thus with “basin discharges” these rivers (St Lucie and Caloosahatchee)  are already being drowned out during high rain events, and thus when Lake O’s water comes on top, well, it  is the “nail in the coffin” so to speak.

I just needed to explain that before we begin….

~ So today, as in the previous post,  I will be speaking about both basin and Lake O water.

Referring to my brother, Todd’s, graph at the top of the page, you’ll notice right away the destructive-discharge numbers are much larger for the  Caloosahatchee, than the St Lucie, as it is much larger estuarine system.

As we can see comparing the two charts labeled “Cumulative Discharges 2010-2019” below, both the St Lucie and the Caloosahatchee’s  highest year for discharges, by far, was 2016. But whereas the St Lucie received 842,000 acre feet of water, the Caloosahatchee’s water number is a whopping 2,950,926 acre feet! That would mean one foot of water on 2,950,926 acres of land.

You’ll remember from last time that “acre feet” is a very easy way to calculate. “Acre feet” means one foot of water on top of one acre of land. This 2016 Caloosahatchee 2,950,926 acre feet of water would just about cover, by one foot, Lee County, Collier County, and Hendry County – counting land and water within boundaries – as the acreage of these three counties adds up to 3, 012,450 acres.

Lee, orange; Collier, blue; and Hendry, green equals 3,012,450 acres of land so 2,950,926 acre feet of water would just about cover this area.
TT3

Again, this visual is meant to give perspective on the tremendous amount of land this amount of water would cover. Often when we hear “acre feet” we don’t put “two and two” together. Once one realizes the number of acres of land  that would be covered, it is astounding!

~But then, of course! These waters used to flow naturally as sheet-flow from the Shingle Creek area up in Orange County all the way south to Florida  Bay.

Continuing on, we see that in second place,  although the St Lucie’s second worst year was 2013, for the Caloosahathcee it was 2017, and then 2013. The fourth worst, for both estuaries was 2018.

Please compare the charts below of both rivers to see other differences from 2010-2019. Interesting… In the future, perhaps we can ask why 2018, in fourth place, was by far the most horrific year for the Caloosahtchee. Certainly it has to do with that sediment, nitrogen and phosphorus feeding cyanobacteria. As we know, in 2018, Lake Okeechobee was 90% covered in a cyanobacteria (blue-green algae) bloom…

*Please note that the charts look similar below; look closely to see that the first is for the CALOOSAHACHEE and the second is for the ST LUCIE. Thank you Todd for these awesome visuals!

CALOOSAHATCHEE 2010-2019 basin and Lake O
ST LUCIE 2010-2019 basin and Lake O

Go to http://eyeonlakeo.com, Todd’s website for more ways to easily access and compare Calooshatchee, St Lucie and other information.

Former blog post: Destruction by the Numbers post that inspired this post: https://jacquithurlowlippisch.com

Destruction by the Numbers, S-80 2010-2019, SRL/IRL

“The throat of our river was cut by the canals.” ~Ernest Lyons 1905-1990

S-80 Spillway at St Lucie Locks, Cumulative Discharges , By Calendar Year, 2010-2019 courtesy Todd Thurlow: http://eyeonlakeo.com/Historical/S-80/index.html

Today, I begin a series of blog posts under the title: “Destruction by the Numbers,” based on new information my brother Todd has added to his website: http://eyeonlakeo.com.

The first slide we will study is calculated under Historical Discharge Graphs for “S-80, Calendar Year 2010 to 2019.”  S-80 is the Army Corp of Engineers’ structure located at the C-44 Canal that discharges water to the St Lucie River/Indian River Lagoon from two sources. First, from the basin surrounding the C-44 Canal; and second, through S-308 at Lake Okeechobee.

Todd’s chart allows us to isolate the most recent decade, 2010-2019, and see that the highest discharging year during this time was 2016 at 847,773 acre feet. 2016 was by far the worst year in recorded history for cyanobacteria blooms being discharged from Lake Okeechobee and spreading throughout the river system. There was such massive blue-green algae build-up at Bathtub Beach that the waves and shoreline were completely green.

Don’t be intimidated by the left axis’ measurement of acre feet. Acre Feet is easy to calculate as it means exactly what it says. The acreage noted, in this instance, 847,773 acres, would be covered by one foot of water.

For reference, I will use the Everglades Agricultural Area, (EAA), located underneath Lake Okeechobee that we talk about all the time. This farmed area, mostly sugarcane, is 700,000 acres. So 847,773 acre feet of water —dumped into the St Lucie River from S-80, in 2016 –would cover the entire EAA, and more, by one foot of water!

~The map below shows the EAA in a salmon color.

Back to the chart. The next worst year, following 2016, was infamous 2013, the year that became known as the “Lost Summer,” and really started the river’s revolution at 671,067 acre feet. At one foot deep, the amount of water discharged would just fit inside the boundaries of the 7000,000 acres of the Everglades Agricultural Area. It is interesting to note that 2017, a year not often mentioned, closely followed with 661,000 acre feet.

2018, a horrible water year, fresh in our memories, actually came in fourth at 402,116 acre feet! Obviously timing and temperature are factors too.

~2010, 2015, 2012, 2014, 2019, and 2011 follow. Of course 2019 is not even finished. It will be interesting to see where it ends up.

As we would have guessed, 2016’s toxic algae health hazard was the highest destruction by the numbers year in the past decade. But what we would never have estimated is how much water was discharged to the St Lucie River/Indian River Lagoon through S-80 in the 1950s and 60s. This number will truly blow your mind. But we’ll save that for the next “Destruction by the Numbers.”

The EAA is labeled and shown in a salmon color. It is approximately 700,000 acres.
S-80 is located along the C-44 Canal that connects Lake Okeechobee to the South Fork of the St Lucie River. Maps courtesy of the SFWMD.

“Too Unthinkable” blog post visually showing the destruction of 2016: https://jacquithurlowlippisch.com/tag/bathtub-beach-algae/