Commentary: Cement Dust and Nassau’s Waterways


Editor’s note: St Marys Riverkeeper — one of 15 Riverkeeper units in Florida — fields scores of trained water-testing volunteers in Georgia and two Florida counties. That includes all the waterways in Nassau County. If it weren’t for Riverkeeper, we would have far less data about the health of our creeks, rivers and marshes than our lightly-staffed health department could possibly provide. That makes this commentary a particularly important document.

By Emily Floore

St. Marys Riverkeeper Executive Director

I would like to take this opportunity to comment on behalf of the St. Marys River and its tributaries as well as St. Marys Riverkeeper members and supporters on the recent discussions around the Ocean Highway and Port Authority (OHPA) Master Plan and the shipments of cement and fertilizer to the Port of Fernandina Beach.

Riverkeeper is concerned about known contamination the cement powder will have on the health of our waterways. Special attention should be focused on the species that inhabit this area and the vital role they play in the local ecotourism industry and in mitigating climate change.

Cement powder shipped into the Port of Fernandina Beach has generated contamination issues for both air and water quality. It was observed by concerned residents of Fernandina Beach that there were impacts on Alligator Creek, a waterbody that empties into the Amelia River at the port. Residents have reported broken bags, machinery covered in dust, uncontained piles of the powder on the ground, and trucks loading the bags for transport only being partially tarped. With each bag containing two tons of concrete powder, the residual dust released during transport or from a bag breakage can easily make its way down storm drains to the Amelia River or Alligator Creek, although this is not allowed by Florida Department of Environmental Protection. The procedures to stop pollutants from entering a waterway do not seem to be adequate, and protecting the workers and the surrounding neighborhood seems to not be of priority. It is the obligation of the port to educate the workers on how to properly handle any spills or disposal to ensure that both the port employees and the local area are protected.

Cement dust contains heavy metals such as chromium, nickel, cobalt, lead, and mercury, and the oxides can react with water droplets forming acid rain, which damages vegetation and alters soil and water pH levels. Lime is a major component of cement and dissolves easily in water increasing the alkalinity (pH 11 to 13) to harmful levels, resulting in fish kills and impacting other aquatic life. It has been observed by the neighbors who regularly walk along Escambia Street, that the birds that roost at the mouth of Alligator Creek have not returned, begging the question as to whether the cement dust is the cause. Although there is signage along Escambia Street to not fish in the water due to water quality advisories, people are still observed setting bait traps and fishing.

Spartina alterniflora is a native smooth cordgrass that is found growing in tidal flats, salt marshes and beaches. These grasses bloom from summer to fall and occur only during natural conditions in wetlands with soil pH ranging from 3.7 to 7.95. Cement dust can coat the surrounding habitat and vegetation, which results in stunted plant growth and reduced production. In addition, the toxicity is harmful for any animal consumption. Inhibiting the growth of plants within a wetland system decreases the critical role they play in filtering water before it reaches the Amelia River and prevents flood protection during heavy rain events.

Spartina grass habitats are harsh due to the saltwater content in the water. They represent one of the few locations on the planet where a monoculture of plants naturally grows. No other plant has adapted to grow in these conditions. If these plants are killed off, it’s not likely that even an invasive plant can backfill the niche. If the plants die and their roots are gone, it would not be long before extreme erosion of soil could cause the permanent destruction of the marsh. Healthy coastal habitats are carbon sinks – playing an important role in mitigating climate change through their ability to absorb and store large quantities of carbon dioxide.

Consideration should be given to the endangered and threatened species that migrate and/or breed in the area. With a dissolved oxygen impaired waterbody and high levels of bacteria, sources of food may become limited for many of our critical year-round and seasonal species. U.S. Fish and Wildlife Service (FWS) IPaC resource list has identified several threatened and endangered species that could be potentially affected by activities in the area including critical habitats for Birds of Conservation Concern. Utilizing the Endangered Species Act, Clean Water Act, and Migratory Birds Treaty Act, appropriate regulations and maximum conservation efforts should be followed by any person, organization, or industry that plans to conduct activity that may negatively impact or impair habitat area and food supply.

The Amelia River is classified as a Class III waterway, and the state of Florida lists the following uses for Class III waters as: fish consumption, recreation, and propagation and maintenance of a healthy, well-balanced population of fish and wildlife.

The Amelia River is a nursery for sharks and is home to many fishing industries, both commercial and recreational. A healthy waterway is needed to sustain the balance of the river’s ecosystem.

Salt and brackish marsh grasses are estuary nurseries for many species of fishes and invertebrates and provide forage and nesting habitat for many birds and mammals. In addition to Spartina alterniflora, a few of the other common salt marsh flooded soil species include Juncus roemerianus (black needlerush), Distichlis spicata (salt grass), Scirpus americanus (three square) and Panicum virgatum (switchgrass).

Current studies suggest that mangroves and coastal wetlands annually sequester carbon at a rate 10 times greater than mature tropical forests. They also store three to five times more carbon per equivalent area than ropical forests.

One of Riverkeeper’s flagship programs is water quality monitoring. We are focused on identifying sources of nonpoint-source pollution (which are pollutants carried by runoff) in our watershed through a dedicated citizen science water quality monitoring effort.

Using Georgia Adopt-a-Stream monitoring protocols for chemical and bacterial sampling, our team of trained staff and volunteers monitor over 50 sites, including several public access sites in Fernandina Beach regularly to build an extensive water quality database. This tool is used to report on the overall health of the St. Marys River, available on Riverkeeper’s website, so people can quickly check the water quality of where they are boating or swimming and help communities apply for funding to remediate failing septic systems.

Enterococci and Escherichia coli, E. coli, are bacteria that live in the intestinal tracts of warm-blooded animals, including humans, and are good indicators of the presence of fecal waste in a waterbody. E. Coli is used to identify fecal contamination in freshwater while Enterococci is used in more saline waters. The U.S. Environmental Protection Agency (EPA) states, “Significant amounts of [bacteria] in a waterbody can negatively affect the recreational and economic value of the aquatic resource. Overabundance of fecal bacteria in the water can cause beach closures, swimming and boating bans and closures of fishing and shellfishing areas.”

EPA’s recommended standard for Enterococci in marine recreational waters is a geometric mean of 35 Colony Forming Units (CFU)/100 ml. This geometric mean standard is based on 19 gastrointestinal illnesses per 1,000 swimmers at marine beaches. EPA’s recommended E. coli level standard is based on 8 people out of 1,000 might get sick and is 126 CFU/100 ml.

Units are CFU/100 ml Good (0 – 235) | Fair (235-536) | Poor (>536)

  • ·  Designated Swimming: (0-235)
  • ·  Moderate Swimming: (235-298)
  • ·  Less Swim / Contact: (298-410)
  • ·  Infrequent Contact: (410-600)
  • ·  Avoid Swimming: (>600)

Alligator Creek at Eighth Street (Riverkeeper sampling results): August 3, 2022 1,033 CFU/100 ml; August 9, 2022 1,233 CFU/100 ml; August 18, 2022 800 CFU/100 ml; September 9, 2022 600 CFU/100 ml; September 22, 2022 400 CFU/100 ml; October 5, 2022 167 CFU/100 ml; November 2, 2022 467 CFU/100 ml; November 21, 2022 667 CFU/100 ml; December 7, 2022 333 CFU/100 ml; January 4, 2023 400 CFU/100 ml; February 1, 2023 1,766 CFU/100 ml; Sampling on Escambia Street was 1,900 CFU/100ml.

On August 12, 2022, St. Marys Riverkeeper issued a Water Quality Alert advising residents to avoid swimming and fishing on Alligator Creek (Escambia Slough) in Fernandina Beach, due to unsafe levels of Escherichia coli (E. coli). Per protocol, Riverkeeper contacted the City of Fernandina Beach, Florida Department of Environmental Protection (FDEP), and Nassau County Department of Health (DOH) to raise public awareness about the contamination. Since then, Riverkeeper increased its sampling of the site and has coordinated additional sampling of the creek with FDEP in partnership with property owners, WestRock, to access more sampling sites. FDEP collected water samples to test for chemical parameters (pH, dissolved oxygen, conductivity, etc) and run DNA tracers for human, avian, and dog. The hope is to get a better understanding of the source of the E. coli contamination and work collaboratively with the local community to resolve the issue. FDEP biological markers were analyzed and found that only avian Helicobacter GFD were detected in samples collected. Additional sampling as occurred include a new site at Dade Street and Fifth Street.

In June 2022, the Watershed Assessment Verified and Delist Lists determined that the Amelia River (WBID 2124A) did not meet water quality standards for aluminum, iron, and dissolved oxygen and two of the three elements have been added to the State’s Verified List of Impaired Waters and the Clean Water Act Section 303(d) list. The process will now begin to determine the TMDL to represent the maximum amount of pollutant loading that can be discharged to a waterbody and have its designated uses met. (FDEP, 2020-2022 Biennial Assessment Final Verified and Delist Lists).

FDEP comments regarding metal impairments on the Final Verified List (FDEP, 2020-2022 Biennial Assessment Final Verified and Delist Lists Excel sheet):

  • –  Iron impairment: “This waterbody is impaired for this parameter based on the number of exceedances for the sample size. After further investigation, FDEP cannot rule out the possibility of anthropogenic sources. This parameter is being added to the Verified List and the department is requesting EPA add it to the 303(d) List.”
  • –  Aluminum impairment: “This waterbody is impaired for this parameter based on the number of exceedances for the sample size. This parameter is being added to the Verified List and the department is requesting EPA add it to the 303(d) List.”


Riverkeeper’s science-based water monitoring program is a critical resource when addressing local stakeholders and when advocating on behalf of clean water to state and local enforcement agencies. Clean water is vital to the health of all living things, vibrant communities, and strong economies. With two already impaired waterways in direct connection with the port, Riverkeeper advises against more stress being put on the local ecosystem by removing the shipments of large bulk bags of cement powder and not bringing in more.

OHPA Commissioners should address many of the complex issues in a thoughtful manner. The public has been intimately involved in the decision-making process. Riverkeeper knows that OHPA and the port will give considerable thought to the comments provided in this letter and hope that the efforts today will develop a strong foundation for future management decisions at the port and with the Caity of Fernandina residents who are very passionate about the health of their environment.

(The St. Marys Riverkeeper (Riverkeeper) is a 501(c)3 private environmental advocacy organization that was formed in 2016 with the charge to protect the St. Marys River and its tributaries from harm and engage the community that calls the watershed home in that protection. Our work as an independent voice for the St. Marys River is made possible by the financial support of donations and memberships of concerned citizens within the watershed and surrounding region. The St. Marys River watershed is the focus of our work to improve water quality in areas that are designated as swimmable and/or fishable, ensure the river thrives for future generations with our work on resiliency projects and community partnerships, promote low impact development in a fast-growing area, and advocate against industrial threats in our underserved communities.

As a border river, the St. Marys River watershed comprises four counties – two in Georgia and two in Florida with roughly 60,000 residents who depend on the health of the river for tourism, recreation, commercial fishing, and safe drinking water. Arising from the Okefenokee Swamp, the St. Marys River flows 130 miles to the Atlantic Ocean at Cumberland Island National Seashore. The watershed has more than 3,000 miles of streams and tributaries, is comprised of 40% wetlands, and is home to many endangered and threatened species such as the Atlantic sturgeon.)

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Alyce Parmer
Alyce Parmer (@guest_67289)
1 year ago

Alarm bells should be going off in every person’s head over the water quality issues in our waterways. Say no to concrete and fertilizer at the port, unless and until the management can demonstrate with certainty safe handling policies and practices are in place and enforced.

Pam Smith
Pam Smith (@guest_67290)
1 year ago

This is a sad state of affairs when state & local officials do not prioritize the health of the water, sea fauna & flora & humans over profit. None are doing their jobs. Instead we & the environment around us as well as children & grandchildren are eating & swimming in toxins & E. coli…literal sh-t.

Troy Walker
Troy Walker (@guest_67324)
1 year ago
Reply to  Pam Smith

Rayonier applied for permit to dump 26 million gallons of waste daily into the Amelia river.
I doubt a little bit of cement dust is going to be a deal breaker where the environment is concerned.

Tammi Kosack
Tammi Kosack(@tammi-kosack)
1 year ago

And this just in…. Just posted on the Port website:
February 22, 2023 Board Meeting Port Master Plan
Questions need to be asked.

Noble Member
1 year ago
Reply to  Tammi Kosack

Strange? “Until Further Notice?” They meet on the 2nd and 4th Wednesday of every month. They could have said that this meeting was canceled and the next meeting would be on the 2nd Wednesday of March? Are they planning to sneak a meeting in between now and then? I guess you can tell I have trust issues with the OHPA.

Peggy Bulger
Peggy Bulger(@peggy-bulger1949gmail-com)
1 year ago

The recent toxic disaster at East Palestine, OH should give our state and local elected officials a clear mandate to ensure that corporations and entities who profit from the transport of toxic materials do not start a new enterprise here in Fernandina Beach and our tiny port. The port has existed for decades without transporting cement and fertilizer and this new push to put profit over people is disgusting, in my humble opinion.

Mark Tomes
Mark Tomes(@mtomes)
1 year ago

Emily’s excellent article reminds me that there will be a water quality testing training next Saturday, Feb 25, up in Folkston. See the St Marys Riverkeeper website for details.

Mike Harrison
Mike Harrison (@guest_67310)
1 year ago
Reply to  Mark Tomes

Thanks, Emily. River keeper does good work. About the large and variable ecoli levels in Alligator Creek: 1. How does rainfall affect the results? 2. How many septic tanks are there in the Creek’s catchment area?

Lynda Bell
Lynda Bell(@lyndabell)
1 year ago

Thank you St Mary’s Riverkeepr, Emily, for such a well written article clarifying the ecological impact

Margaret Kirkland
Margaret Kirkland(@kirkland-mrk)
1 year ago

Thank you to Emily Floore for her informative article and letter to OHPA officials, for the water testing program and for speaking out on the threats we face. It is critical that we protect our fragile environment for our own and our children’s health as well as for the sustainability of our economy. The health of our environment underlies the health of our economy. We must protect it.

Kevin B
Kevin B(@kevin-b)
1 year ago

Great article, however, it doesn’t state why the Alligator Creek at Eighth Street (Riverkeeper sampling results) are so high? Especially compared to Dec 2022 & Jan 2023 scores. In one month, testing results on February 1, 2023: 1,766 CFU/100 ml; Sampling on Escambia Street was 1,900 CFU/100ml.
Is this alarming test score a direct result of cement dust or some other contamination?