This Week's Water Conditions Update

September 19, 2025

Water Conditions Tracker

Lake Okeechobee Levels & Caloosahatchee Flow Impacts

On 9/17/25 Lake Okeechobee was at 13.05 feet, increasing by 0.25 feet in the past week. The weekly average flow at S-79 was 6,579 cfs (cubic feet per second) and flow from the Lake at S-77 was an average of 0 cfs. The 14-day average flow at S-77 was 0 cfs. The 14-day average flow at S-79 was 4,483 cfs and has been in the damaging flow envelope (>2,600 cfs; RECOVER 2020) for 15 days.

For more information on Lake Okeechobee and estuary conditions go to the latest Caloosahatchee Conditions Report.

Water Surface Temperature

This Week

Daily Average for September 17, 2025


Gulf of Mexico: 85.5°F

Caloosahatchee (Beautiful Island): 85.2°F

Lake Okeechobee: 84.6°F

Last Week

Daily Average for September 10, 2025


Gulf of Mexico: 85.8°F

Caloosahatchee (Beautiful Island): 86.0°F

Lake Okeechobee (Polesout3s): 84.9°F


Marine Lab Partners with Shell Museum to Assess Biodiversity of Oyster Reefs

Recently, SCCF scientists found some mollusk species they couldn't identify while assessing biodiversity on several natural oyster reefs in San Carlos Bay and Matlacha Pass. "Several bivalve and gastropod specimens were particularly challenging as they were small juveniles,” said Marine Lab Director Eric Milbrandt, Ph.D. “Fortunately, Sanibel is home to some incredible expertise, especially in molluscan taxonomy.”

Weekly Rainfall Totals

WP Franklin (S-79): 3.91" Ortona (S-78): 1.77" Julian Keen Jr. (S-77): 0.94"

Virtual Water Quality Tour from Lighthouse Beach Park

Click here or on the image above to take a virtual tour from above Lighthouse Beach Park to see how the water looked this week. Photo was taken on 9/17/25 at 2:08 PM on a falling tide (1.1 ft). The 14-day average flow at S-79 was 4,483 cfs.

Red Tide

On 9/12/25, the FWC reported that the red tide organism, Karenia brevis, was observed at background concentrations in one sample each from Northwest Florida and Florida’s East Coast, in Bay and Flagler Counties. In Southwest Florida over the past week, K. brevis was not observed.

Blue-Green Algae

On 9/15/25, sampling for cyanobacteria by the Lee County Environmental Lab reported Microcystis and Planktothrix as present upstream of the Franklin Locks, appearing as some light streaks.

On 9/16/25 satellite imagery of Lake Okeechobee showed the presence of an algal bloom but there was insufficient data to estimate the bloom area at this time. The previous area of the bloom measured on 9/8/25 covered about 220 square miles, or 47% of the lake.

Become a Citizen Scientist and Get the Algae Reporting App Today!

SCCF wants to know when and where all types of algae sightings occur to monitor conditions around the islands and to investigate algae bloom occurrence with patterns in seasonal weather changes and Lake Okeechobee water management practices.


Click on and bookmark this link to report an algal bloom sighting.

Resources To Follow:

To learn more about our current water conditions, click on the following links:


Water Quality Dashboard


Water Quality FAQ

Find answers to some of our most commonly asked questions regarding water quality and more.


Water Conditions Update Archive


Caloosahatchee Conditions Report

A collaborative, weekly analysis, including recommendations for water managers regarding Lake Okeechobee flows.


RECON

SCCF's River, Estuary, and Coastal Observing Network is a network of eight optical water quality sensors deployed throughout the Caloosahatchee and the Pine Island Sound estuary to provide real-time water quality data.


Caloosahatchee River Virtual Tour



Red Tide Resources


NOAA HAB Monitoring System - Lake Okeechobee

Click here to subscribe to the Weekly Water Conditions Tracker


Click here to subscribe to Connecting You to SCCF and other SCCF mailing lists.

LinkedIn Share on LinkedIn
Stay Connected!
Facebook  Instagram  Youtube