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Caloosahatchee and Estuary Conditions OLD


Corps Initiates Water Releases for Caloosahatchee Health

Since February 4, 2011,  the U.S. Army Corps of Engineers has been authorizing pulse releases from Lake Okeechobee in order to bring salinity levels in the Caloosahatchee and estuary to more natural levels.  These welcome pulse releases broke the pattern of increasing salinities resulting from water being cut off to the Caloosahatchee on December 15, 2010. Lack of freshwater flow to the Caloosahatchee in the dry season causes the upper estuary to get too salty and the freshwater system upstream of the Lock to stagnate spawning algae blooms.

The pulse release is designed to average 300 cubic feet per second (cfs) into the Caloosahatchee estuary, measured at W.P. Franklin Lock and Dam (S-79), over the seven-day period. The Corps anticipates the total pulse release effect on the lake level to be about a sixth-of-an-inch off the lake.

Other News

The Rivers Coalition, a group of 55 organizations and businesses representing a community over 300,000-strong, advocates for the east coast St. Lucie river estuary.  On February 9, 2011, they passed a Resolution supporting dry season flows to the Caloosahatchee.  The Resolution was forwarded to the SFWMD and the Army Corps of Engineers.  We are tremendously grateful for thier ongoing support.  Click here to read the Resolution.  Click here for more info on the Rivers Coalition.

SCCF wrote the Lee County Board of County Commissioners for assistance in providing documentation to provide a basis of support for providing water from Lake Okeechobee to benefit the estuary and river.  Click here for Feb. 1, 2011 letter.


The Fort Myers News-Press continued their River at Risk series with a February 12, 2011 story about the connection between Lake Okeechobee and the Caloosahatchee.  Read story.

Click here for info on algal blooms in the Caloosahatchee.

SCCF signed onto the November 2010 nomination of the Caloosahatchee as one of the Ten Most Endangered Rivers in the U.S.  The nomination, prepared by the Conservancy of Southwest Florida, was also signed onto by Riverwatch (the Caloosahatchee River Citizens Association).  Click here for PDF of nomination.  Click here for accompanying map.

SFWMD Governing Board Meeting at FGCU on Wednesday, Nov. 10

Our river and estuary need your voice to speak on their behalf! On Wednesday, November 10 the South Florida Water Management District (SFWMD) Governing Board will hold their monthly meeting in Fort Myers at Florida Gulf Coast University (FGCU). At this meeting the SFWMD will be voting on an initiative of grave importance to the health of the Caloosahatchee, our native fish and wildlife habitats and our region's $3 billion economy.   Click here for talking points.  Click here for our Action Alert and to e-mail the Governing Board.

Summer 2010

SCCF's Rae Ann Wessel and James Evans from the City of Sanibel's Natural Resource Department prepared a paper at the request of Vice Mayor Mick Denham in July outlining the inequities in the water management system.  Click here for a PDF.

NBC-2 went out with SCCF staff on July 21 when they serviced one of the RECON sensors.  Click here for link to story.

Optimum flow at S-79 (W.P. Franklin Lock, which includes Lake Okeechobee releases from S-77 as well as water from the Caloosahatchee watershed) is between 650-800 cfs; flows over 2,800 cfs are damaging. 


On July 22, SCCF received notification from the Corps of a new schedule with reduced flows to begin on July 23.  Click here for the Corps' July 23 press release.  The release notes that "Because the lake level is still high, and seasonal predictions indicate releases are needed, we’ve decided to make releases up to 2,000 cfs to the west (Caloosahatchee) and 730 cfs to the east (St. Lucie)."  The Caloosahatchee flow will be measured at S-79, which includes the Caloosahatchee watershed runoff in the flow assessment. 

On July 11, the Corps began a 12-day pulse release schedule with a target average flow through S-77 of 4,000 cfs (July 11 schedule; Corps' press release; SCCF Action Alert).  On July 1, the Corps had lowered the target flow with a 10-day pulse release schedule.  July 1 scheduleClick here for our action alert about the July 1 schedule.  Previous pulse release schedules were issued on May 22 and May 12
Aggressive releases began in March and pulse releases at 4,000 cfs began on May 3. 

Army Corps web pages with lake release stats:   S-77     S-79**   All gates and lake level

The SFWMD has been working to find alternative short-term storage options for the excess water.  Click here for map and for list of current options.

Current Lake O level

lake o levels
Lake Level as of 8/5/10.
Click Lake Levels chart left for a larger PDF of the graph.











Graph from the U.S. Army Corps of Engineers




Some background

Our exceptionally wet "dry" season raised lake levels in May to 15 feet (see solid blue peak in graph below right), a level more normal at the end of the wet season, in August or September.

Unseasonably high rainfall levels have resulted in high volume releases into the Caloosahatchee from Lake Okeechobee.  In May, so much excess water was being released that the Caloosahatchee was pushing freshwater all the way out to the mouth of the river at Shell Point, eliminating the critical estuary mixing zone.  This will negatively impact seagrasses, oysters, scallops, fish, crabs and the federally endangered smalltooth sawfish and its endangered habitat.  Releases from the lake to the Caloosahatchee and St. Lucie Rivers are managed by the U.S. Army Corps of Engineers (Corps) and by the South Florida Water Management District (SFWMD). 







The graph right (Flow S79) shows recent observations of water flow coming out of S-79 as compared to historical measurements made since 1996.  The colors represent the percentages of all observations during this 13-year period that fall within a specific range.  The black line represents S-79 flow in 2010.  Graph by SCCF Marine Lab.  Data source USACE DBHYDRO: DJ237
Click on graph for larger PDF image

Public meetings and press

Army Corps Jacksonville District Commander, Colonel Alfred A. Pantano, Jr., spoke to Palm Beach County Commissioners on Tuesday, May 18 about the lake releases and status of dike repair.   Click here.

May 11, 12 & 13 meetings with the Corps and District  Read our Action Alert

On May 10, NBC-2 ran an interview with SCCF Natural Resource Policy Director Rae Ann Wessel.

You can reference SCCF’s guest opinion in the May 7, 2010 News-Press about the impacts on the Caloosahatchee of this year’s heavy rain combined with releases from Lake Okeechobee.

On May 11, the News-Press ran an editorial urging attendance at the May 11 Army Corps meeting

**  See below right for map showing locations of the three lock-and-dam structures on the Caloosahatchee:  S-77, S-78 (at Olga) and S-79 (W.P. Franklin Lock).   S-77  at Moore Haven is the structure regulating releases from Lake Okeechobee.   S-79 is at the Franklin Lock, which is downstream of S-77.  Releases from S-79 therefore includes the water released from the lake at S-77 plus runoff from the Caloosahatchee watershed.  Look for "flow."  cfs = cubic feet per second.  Optimum flow into the Caloosahatchee at S-79 is 650-800 cfs.  For the report listing all gates and the lake level, click here.

Some background

 recon and lock mapOptimum flow into the estuary at the Franklin Lock (S79) is between 650 – 800 cfs. The Caloosahatchee today serves as the major outlet for up to 70% of excess water from Lake Okeechobee. The solution? More storage both short-term and long-term.

This spring, SCCF continued asking the South Florida Water Management District (SFWMD) for an inventory of possible short-term storage options that could include: landowners north of the lake being paid to “harvest” water; the Nubbin Slough STA north of the lake (which has been dry while under repair but is capable of holding excess water); plus canals and fallow fields south of the lake in the EAA, as well as state-owned lands Holeyland and Rotenberger, also south of the lake.   We have also asked for an inventory of options in the Caloosahatchee watershed that could take excess flows, such as the 11,000 acre Berry Grove reservoir site, and fallow farm fields on Babcock Ranch.  Our request has been for an inventory of possible storage sites, estimated capacity of these sites and how close they are to their capacity.

Even without major earth works there is the capacity to fill canals and saturate lands that can provide storage and evaporation as an alternative to blowing out the estuaries. To date – while the health of our estuary is being damaged -- we are still waiting for a response. Why?

The SFWMD Governing Board will be discussing this issue at upcoming meetings.   We urge you to contact the Governing Board and ask them to look for alternative and unconventional storage solutions to protect the estuaries on both coasts.

Remember the devastation of the estuary and river in 2004-2005.   Let’s not sit by and allow lack of creative action to destroy our estuary again.


Posted 5/10/10   Updated 7/12/10