MARTIN COUNTY, Fla. — Billions of gallons of water filled with runoff from surrounding urban and agricultural areas are dumping into the St. Lucie River after significant rainfall filled the new C-44 Reservoir and surrounding canals to dangerously high levels.
Wednesday, reports from the Army Corps of Engineersshowed more than 1.6 billion gallons of freshwater was released from the St. Lucie Lock and Dam.
Since the discharges began the end of August, and since then more than 5.5 billion gallons of water were discharged, discharges that don't appear to be letting up any time soon.
Unlike other discharges, however, this water source isn't coming from Lake Okeechobee, but is instead funneling in from the C-24 canal, the C-23 canal, the Ten Mile Creek and— for the first time— the $340 million C-44 Reservoir.
When the reservoir opened in 2021, it was designed to hold up to 15 feet of water to prevent more than 16 billion gallons of water containing runoff from pouring into the river.
Now, almost three years later, a "seepage issue" is keeping it from operating correctly.
WATCH: C-44 reservoir hampered by seepage after pumps turned on in 2021
WPTV's Michael Williams reported on the issue in April, and spoke to Col. James Booth, who was the Army Corps Jacksonville Commander at the time.
"The issue with the seepage isn’t a dam and levy safety issue," said Booth.
Booth called it a "maintenance issue" and said crews were working on fixing yet.
Yet, five months later, the reservoir only comfortably holds about seven feet of water, or 10 feet at maximum, and after rain inundated the Treasure Coast the past few days, Florida Oceanographic's Mark Perry said the reservoir is just below capacity.
At the same time, surrounding canals are filled to the brim, leaving the Corps no choice but to release the water.
"And that’s causing a real problem with the estuary, especially with phosphorus and nitrogen," said Perry.
Perry said nutrient-filled freshwater can kill off the wildlife reliant on brackish saltwater to survive, particular oysters and seagrass.
Maps from EyeOnLakeO.com show phosphorus levels pouring into the River are already at least twice the target amount.
WATCH: Business owners in Stuart feeling impacts of Lake Okeechobee water releases
"Nitrogen concentrations are about 1,400 parts per billion," said Perry. "They're supposed to be 720."
At the same time, the river's salinity levels near the Roosevelt Bridge are at a two. For context, a 10 is the minimum level of salinity an oyster can thrive in, and zero indicates freshwater.
"And if that stays in the estuary for several days it can kill the oyster reefs, kill the seagrass beds," said Perry, "and we’re really in trouble."
"Should we even be in this position in the first place?" asked WPTV's Kate Hussey.
"It's difficult," said Perry.
St. Lucie Settlement resident Jeff Endriss has another concern.
The St. Lucie Settlement community at the end of Salerno Road is just downstream of the St. Lucie Lock and Dam, a low-lying community that has been flooded by significant discharges before.
WATCH: 2-week pause in Lake Okeechobee discharges is 'woefully inefficient'
Jeff Endriss said his house hasn't flooded in decades, ever since the Corps started coming out to monitor water levels and mitigate flooding.
However, he's hoping the billions of gallons of water likely still to discharge won't push his luck.
"And my main concern is the wildlife," said Endriss. “The water is just not as clean, it’s just kind of smelly. It looks like chocolate milk."
Aerials taken by Chopper 5 indeed show the St. Lucie River dark and murky.
We reached out to the Army Corps of Engineers.
A spokesperson told us the releases from the C-44 reservoir were stopped midday August 30 due to all of the rainfall we started receiving, but confirmed to WPTV the Corps will look for opportunities to continue making releases.
The spokesperson also said releases from the reservoir accounted for just 6% of the total flows into the St. Lucie Estuary, while the remainder was primarily local basin runoff from rainfall.
WATCH: Long-awaited C-44 reservoir opens in Martin County
“Even in the Operational Testing and Monitoring Period (OTMP), the C-44 Reservoir is providing benefits to the St. Lucie Estuary by improving the timing, quality, and quantity of flows into the estuary. If the reservoir didn’t exist, the local basin runoff we collected in the early part of the wet season would have freely flowed into the estuary with a higher nutrient content," wrote Col. Brandon Bowman, the Jacksonville district's new commander, in an email to WPTV.
A spokesperson for the district also said their water managers are watching the total inflows into the estuary from C-23, C-24, Ten Mile Creek, and the tidal basin to evaluate when and how much to release to target optimal total inflows.
"As they evaluate current conditions, they will make adjustments daily to not exceed 1,400 cfs of total inflows into the estuary, which is the high end of the RECOVER optimal estuarine salinity performance metric of 150-1,400 cfs. Flows within this range will not cause adverse effects to the ecology of the St. Lucie Estuary," wrote the Corps in a statement.
WPTV's previous coverage on C-44 reservoir:
Protecting Paradise
Reservoir hampered by seepage; Army Corps says 'trust in the process'
Stuart
Business owners in Stuart feeling impacts of Lake Okeechobee water releases
Protecting Paradise
Mast: 2-week pause in discharges is 'woefully inefficient'
Protecting Paradise
Long-awaited C-44 reservoir opens in Martin County
Protecting Paradise
