Dredging Increases Salinity and Storm Surge

Dredging Increases Salinity and Storm Surge Credit: Florida Times-Union

For decades, the St. Johns River has been deepened, straightened and manipulated to allow bigger and bigger ships to access Jacksonville's port.

The Florida Times-Union recently released a special report, As the Ocean Creeps In, that takes a look at the impact these alterations to the river have had on saltwater intrusion, tide levels, and storm surge.

According to the report, “The U.S. Army Corps of Engineers, one of the nation’s oldest federal agencies and the overseer of these changes to the St. Johns River, has never studied how more than a century of work [dredging] might make the city more vulnerable to storm surge and flooding."

We urge you to read this outstanding special report in its entirety, but here are some of the highlights:

Saltwater Creeps In

"The river is now a superhighway for Atlantic Ocean water, which in the event of a major storm could present greater risk to downtown and the neighborhoods around it even though they are miles away from the river's mouth."

"In chasing its dreams of a deepwater port, the city has brought the Atlantic Ocean to its doorstep."

"The saltwater transition zone — where Atlantic Ocean saltwater and river freshwater begin to mix — has moved further upstream through the decades. That zone is thought to have been near the Acosta Bridge in downtown in the 1950s....Today the salinity zone shifts between the Buckman Bridge near Orange Park and the Shands Bridge near Green Cove Springs, depending on rainfall levels, meaning it has moved between about 10 and 25 miles south of downtown — about 50 miles from the ocean — over the past six decades."

"'I remember that I used to regularly see grass beds around Sadler Point north of NAS JAX on regular… surveys during 1994-2000,” said Gerard Pinto, a Jacksonville University scientist who helps compile annual checkups on the state of the St. Johns. 'Those areas are now typically bare of vegetation.'"

"Scientists are certain dredging is one of among several man-made reasons behind salinity intrusion in the St. Johns River."

Increased Storm Surge

“The Army Corps acknowledges in its own analysis that the latest 7-foot dredging project could increase water levels in a 100-year storm surge by 3 to 6 inches in the main stem of the river, and by 8 inches in areas closer to the ocean. But the agency — which has nearly unchecked latitude in making such determinations — has, for reasons that are unclear, deemed those potential increases insignificant."

Stefan Talke and Ramin Familkhalili are Portland State University professors who are "studying the cumulative effect that years of deepening projects can have on tides and storm surge intensity within estuaries." Their research of the Cape Fear River in North Caroline discovered that the tidal range — the difference between high tide and low tide — has increased due to decades of dredging.

“The results of the study, the two wrote, ‘suggest a simple but profound lesson: locations in which tide waves have been amplified are also vulnerable to increases in storm surge and flood risk …’”

"The increased tidal changes Talke and Familkhalili tracked are less pronounced along coastal areas and more pronounced further inland, suggesting, they argue, that the cause of those changes lies within man-made alterations to the river rather than driven by large-scale ocean changes like sea-level rise, itself the result of human activity warming the climate. That also means any increase in storm surge intensity would be felt in those more inland areas, too."

"An 1879 annual report from the chief of engineers makes reference to the tide range in downtown Jacksonville measuring about one foot. Today, the range is about 1.8 feet — nearly double. Like Cape Fear, the increased tide range near the coast is much smaller than that, suggesting that man-made activities like dredging are the source of the change."

Flood Waters Rising

"The St. Johns Riverkeeper — a well-known local environmental watchdog — late last year amended an existing federal lawsuit seeking to stop the 7-foot dredge to include an argument that the Army Corps failed to properly study storm surge intensity and its flooding impact."

“A major point of disagreement between the Riverkeeper and the corps is whether the agency’s storm surge study — which acknowledges that the 7-foot dredge could increase storm surge height by as much as 8 or 9 inches in parts of the river close to the dredging project — downplays the potential risks. The Army Corps’ concluded that the potential increases in storm surge are insignificant. It’s not clear in the report, however, why the Army Corps came to that conclusion."

"A 2016 storm surge study for the Charleston project found potential storm surge water level increases in the harbor ranging between about 1.2 inches to a maximum of about 3.6 inches — the lower end of what the Army Corps expects could happen in Jacksonville. In Jacksonville, the Army Corps dismissed the potential increases in water levels without indicating the need for a more refined study."

"After Irma, the agency doubled down on its position. It said the flooding issues 'do not constitute significant new circumstances or information relevant to environmental concerns bearing on the project or its impacts.'"

A City Unprepared

"The city sends mixed signals about how urgently it views sea-level rise and resiliency issues. It’s not clear what Curry’s views are on climate change, and his office did not respond to a request for an interview."

"Last year, the city began working on a state-mandated change to its 2030 master plan that acknowledges in writing the need to prepare for sea-level rise and establishes a working group to start studying the issue within the year. That change faced skepticism from the city Planning Commission — which recommended the City Council not pass it based on fears it would be onerous to business owners."

"At minimum, Hurricane Irma was a wake-up call, but it’s not clear the public or government are galvanized to tackle Jacksonville’s flooding problems."

"'The lesson that is taught by all of this, communities need to be far more engaged and far more informed,' said Davis, the Tulane professor." 

Read comments submitted to the Army Corps of Engineers by Lisa Rinaman, the St. Johns Riverkeeper, on December 29, 2017, regarding the Corps' failure to fully assess potential flooding impacts from the propsed dredging of the St. Johns River.

Click here to learn more about the latest dredging proposal and the potential impacts to the St. Johns.  

Report Ranks Top Polluters of St. Johns River and the Nation

Report Ranks Top Polluters of St. Johns River and the Nation

For Immediate Release
Thursday, March 29, 2018

Jennifer Rubiello, State Director, Environment Florida
jennifer@environmentflorida.org, (818) 203-7625
Shannon Blankinship, Advocacy Director, St. Johns Riverkeeper,
shannon@stjohnsriverkeeper.org, (904) 614-6570

Worst Polluters of the St. Johns River

New Report from Environment Florida Ranks the Top Industrial Polluters

Jacksonville, Fla.– Industrial facilities dumped excessive pollution into Florida’s waterways 270 times over 21 months, the tenth worst total in the nation, according to a new report by Environment Florida Research & Policy Center. However, the facilities rarely faced penalties for this pollution. Environment Florida is releasing its Troubled Waters report as the federal government tries to weaken clean water protections and slash enforcement funding for the U.S. Environmental Protection Agency and the states.

“All Florida waterways should be clean for swimming, drinking water, and wildlife,” said Jennifer Rubiello, state director with Environment Florida. “But industrial polluters are still dumping chemicals that threaten our health and environment, and they aren’t being held accountable.”

In reviewing Clean Water Act compliance data from January 2016 through September 2017, Environment Florida Research & Policy Center and Frontier Group found that major industrial facilities are regularly dumping pollution beyond legal limits set to protect human health and the environment, both in Florida and across the country. After ranking the top ten polluters statewide, local advocates are joining in an effort to raise the alarm for stronger permits, enforceable limits, and more funding for clean water programs.

“The St. Johns River is impaired and vulnerable. Industrial waste and effluent violations, without consequences, won’t fix themselves,” said Shannon Blankinship, Advocacy Director with the St. Johns RIVERKEEPER. “I have seen people fishing, swimming and boating in every single location this report lists as a major violator. These pollutants are toxic to our water, hazardous to our health, and dangerous to the ecosystem.”

Troubled Waters shows that polluters, who are spewing everything from fecal matter to heavy metals to oil and grease into the water, rarely face penalties. In response, the report recommends several measures to ensure stronger enforcement of, and protection for, clean water. Unfortunately, the state legislature passed bills earlier this month that could soon make the pattern of pollution worse.

“Statewide, we know that more needs to be done to hold these polluters accountable when they violate their permits,” Rubiello said. “This is a call to action, and the report is where we can begin.” See the full report at environmentflorida.org.


Environment Florida Research & Policy Center works to protect clean water, clean air, and open spaces. We investigate problems, craft solutions, educate the public and decision-makers, and help the public make their voices heard in local, state and national debates over the quality of our environment and our lives.

OUTSTANDING River Friendly Yard Award kicks off!

OUTSTANDING River Friendly Yard Award kicks off! Winner of the 2016 River Friendly Yard Award

Annually, St. Johns RIVERKEEPER and Florida Native Plant Society’s Ixia Chapter recognize individuals or businesses that have implemented River Friendly landscaping and maintenance practices to reduce their impact upon the health of the St. Johns River and our environment. Eligible candidates for the Outstanding River Friendly Yard Award help to protect our waterways by using low-maintenance native plants, preventing stormwater runoff, and minimizing the use of irrigation, fertilizers, herbicides and pesticides.

How To Enter
Duval County residents must meet criteria based on the University of Florida's Florida Yards and Neighborhoods principles, be a member of St. Johns Riverkeeper and/or Florida Native Plant Society, and submit a photo and statement about the yard to shannon@stjohnsriverkeeper.org, or on social media (Facebook or Instagram) via #riverfriendlyyardaward. You may nominate yourself, a neighbor, family member, or business.

Winner of the contest will receive a $100 gift card and a complimentary landscape analysis with a native landscape expert, compliments of Native and Uncommon Plants. Winners also receive OUTSTANDING RIVER FRINEDLY YARD signage for your home, a recognition photo session with leaders from St. Johns Riverkeeper and Florida Native Plant Society, and potential coverage on the local news.

Deadline and Judging Process
The contest launches March 1, 2018 with judging in late April - early June. The deadline to submit a photo and statement is April 22: Earth Day. Based on the information submitted, three finalists will be selected that best exemplify a commitment to native plants and River Friendly Yard practices. A committee composed of representatives from St. Johns Riverkeeper, Florida Native Plant Society – Ixia Chapter, and Duval IFAS Extension office will then visit the yards of the finalists and select a winner using the attached criteria. 

River Friendly Yard Award recipients will meet most, if not all, of the following criteria:

  • Homeowner uses fertilizer and chemicals sparingly or not at all, waters only as needed, and is tolerant of some weeds and pests.
  • Landscaped area is maintained and attractive (does not contain excessive or overgrown weeds).
  • Landscaped area utilizes drought-tolerant, low-maintenance plant material and groundcover, preferably including 50% or more native plants.
  • Yard does not include invasive plants.
  • If home has an in-ground irrigation system, it is designed to be as efficient as possible, by utilizing water efficient components and strategies (e.g. drip or micro irrigation, soil moisture sensors, rain barrels) based on the type of plants and their individual needs. Homeowner frequently inspects, repairs, and calibrates the system and adjusts timer in accordance to changing weather patterns. 
  • Landscaping and maintenance practices are consistent with University of Florida’s Florida Yards and Neighborhoods principles:
  • Right Plant, Right Place – The plant selection matches the yard’s soil, light, water, and climatic conditions to create a drought-tolerant, low-maintenance yard.
  • Water Efficiently – Follows local irrigation ordinance and only waters as needed. Uses mulch and mows properly to increase plant health and drought tolerance.
  • Fertilize Appropriately - Sparingly uses slow-release fertilizers with little or no phosphorous, and only as needed to minimize runoff into the river or leaching into the groundwater.
  • Mulch – Uses mulch to retain moisture, slow runoff, and control weeds. Does not use cypress mulch. The harvesting of cypress for mulch destroys living trees and important habitat for wildlife.
  • Attract Wildlife – Uses native plants to provide valuable habitat for wildlife.
  • Manage Yard Pests Responsibly – Uses Integrated Pest Management (IPM) techniques to spot-treat and minimize the use of toxic chemicals.
  • Recycle Yard Waste – Leaves clippings on lawn and composts.
  • Reduce Stormwater Runoff - Uses berms or swales, when feasible. Downspouts are pointed toward yard/garden and away from driveways and sidewalks. Permeable materials are used when possible for walkways, paths, etc.
  • Protect the Waterfront - Maintains a 10’ buffer adjacent to any waterway where chemicals and fertilizers are not used to minimize runoff. Is careful to keep chemicals and fertilizers away from impervious surfaces (roads, driveways, sidewalks) to avoid entering storm drains. Storm drains eventually lead to the river, meaning we all essentially live on waterfront property.


Controversial Toxic Chemical Rule Withdrawn

Controversial Toxic Chemical Rule Withdrawn

For Immediate Release

February 21, 2018

FDEP Withdraws Rule That Would Have Allowed More Toxic Chemicals in Florida’s Waters 

JACKSONVILLE, FL — The Florida Department of Environmental Protection (FDEP) recently withdrew a dangerous state rule that would have allowed increased levels of toxic chemicals in Florida’s surface waters. Miami Waterkeeper and St. Johns Riverkeeper, represented by Earthjustice, have been campaigning against this rule since it was proposed in 2016.

“This is a major victory for all Floridians and our wildlife. This process was plagued with problems that would have exposed more Floridians to toxic chemicals in surface waters,” says Rachel Silverstein, Executive Director and Waterkeeper of Miami Waterkeeper. “We are thrilled that the DEP has finally reconsidered the risks and will reexamine its science.”

This rule, proposed by FDEP, was rushed through the Environmental Regulation Commission (ERC), despite having vacant seats that Governor Scott had failed to fill for representatives from the environmental community and local government.

The rule used a controversial method to calculate cancer risk that differed from the U.S. Environmental Protection Agency (EPA) recommended model and the one utilized by every other state in the nation. This resulted in toxic exposure limits that were higher than EPA recommendations for most of the chemicals examined. In short, DEP accepted the likelihood that more Florida citizens might develop cancer with these new exposure limits, using a carcinogenic “chemical risk calculation” that is 10 times (or sometimes 100 times) higher than the current rule allows for some individuals.

Because chemicals accumulate in fish or shellfish, people who eat Florida-caught seafood even just once a week would have increased their cancer risk by orders of magnitude. Subsistence fishers, who eat Florida caught fish daily, like many tribal communities, are the most at risk.

Aside from increasing our cancer risk, this rule would have also hurt the market for Florida seafood, deterring the public from choosing “Fresh from Florida” shellfish and fish.

“Florida’s economy relies so heavily on clean water. This rule would have resulted in a direct hit to the commercial and recreational fishing industry, tourism, and public health. You have to ask who would have benefited from this rule. It certainly wasn’t me, my children, or my fellow Floridians,” said Lisa Rinaman, St. Johns Riverkeeper.

Miami Waterkeeper, the St. Johns Riverkeeper, and Earthjustice have been working with experts to evaluate FDEP’s faulty science and have submitted technical comments to the EPA. The groups also mounted a petition and letter-writing campaign, met with EPA officials, and rallied local municipalities to oppose the rule. Over 11 municipalities passed resolutions opposing the rule.

In 2016, the City of Miami joined the Seminole Tribe in a legal challenge to the rule. After initial setbacks, the City of Miami and the Seminole Tribe won their appeal at the 3rd District Court of Appeals, permitting them to have an administrative hearing on the merits of the rule scheduled for this April. Miami-Dade County also recently decided to join the fight against the rule and intervene in the administrative proceedings.

With mounting opposition and an administrative hearing looming on the horizon, FDEP formally withdrew the rule as proposed and reinitiated rulemaking. In preparation for a revised version of rule, the FDEP “intends to conduct a state-wide fish consumption survey to accurately determine the amount and types of fish commonly eaten by Floridians” before promulgation.

“It’s time for the state to go back to the drawing board and use the best science to protect Floridians from toxic chemicals in our water,” said Tania Galloni, Managing Attorney for the Florida Office of Earthjustice. “We need safeguards so that polluters don’t wreck our fishing and recreation industries.”

Click here for more information about this controversial rule. 

Motion Denied, Dredging Challenge Continues

Below is the press release that St. Johns RIVERKEEPER released on 1/22/18. 


Jacksonville, FL -- On January 19, 2018, Judge Marcia Morales Howard issued an order denying St. Johns RIVERKEEPER's Motion for Preliminary Injunction to prohibit the Army Corps of Engineers (the Corps) and JaxPort from proceeding with plans to dredge the St. Johns River. 

St. Johns RIVERKEEPER was seeking further analysis by the Corps of potential flooding impacts and JaxPort’s revised plans for an 11-mile project before the Deep Dredge could begin.

St. Johns RIVERKEEPER will continue with its ongoing challenge of the Deep Dredge in federal court due to the unmitigated harm that will occur to the St. Johns River and its tributaries and an insufficient environmental and economic assessment of the project by the Army Corps of Engineers.

St. Johns RIVERKEEPER filed the motion due to the failure of the Army Corps of Engineers to evaluate the likelihood of additional flooding as a result of the project and the economic viability of JaxPort’s publicly-announced plans to revise the scope of the dredging from 13 miles to 11 miles.

During the January 4 injunction hearing, the Corps admitted that the agency did not conduct a flood analysis to determine potential impacts, despite concluding that the Deep Dredge will increase the water level in the St. Johns by up to one foot due to increased tides and storm surge in some areas. However, the Corps had previously committed to a special City Council Task Force and federal agencies that no induced flooding would occur.

In addition, JaxPort revealed that it still plans to dredge 13 miles of the St. Johns River, backtracking on last year’s announcement that the Deep Dredge would be shortened to 11 miles. While an 11-mile project would reduce the cost of dredging, it would not reach the pivotal $230 million TraPac terminal, limiting JaxPort’s ability to attract the larger Post-Panamax ships. As a result, the Corps would need to reevaluate the economic benefits to determine if the revised plan still qualified for federal approval and funding.

“Unfortunately, the decision by the Court allows the Corps and JaxPort to begin this risky project before fulfilling their obligation to the river and this community,” states Lisa Rinaman, the St. Johns Riverkeeper. “We can’t afford to wait until we experience more flooding or for JaxPort to make up its mind on the scope of the project before fully assessing the environmental and economic impacts of the dredging. Once the damage is done, it will be too late.”

While the Judge’s decision allows the first phase of the dredging to proceed, the order does permit St. Johns RIVERKEEPER to pursue its unresolved concerns regarding the impacts from additional flooding in the ongoing legal challenge of the Corps’ environmental study of the project.

Click here to read Judge Howard's Order.

For more information about the Deep Dredge and its impacts, click on the links below:

How Will Dredging Impact Sea Level Rise?

How Will Dredging Impact Fisheries?

How Will Dredging Impact Algal Blooms?

Expert Finds Dredging "Economically Infeasible"

JaxPort Announces New Plan for 11-mile Project

Get the Facts About Dredging Proposal

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Dredging Increases Salinity and Storm Surge
Dredging Increases Salinity and Storm Surge
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OUTSTANDING River Friendly Yard Award kicks off!
Controversial Toxic Chemical Rule Withdrawn
Controversial Toxic Chemical Rule Withdrawn

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