The fifth annual State of the River Report for the Lower Basin of the St. Johns River was recently released and shows improvement in some areas but continuing threats in several critical categories.
Since 2008, researchers from Jacksonville University, the University of North Florida and Valdosta State University have reviewed and analyzed data and literature about the river to determine the status and trends of various health indicators. The report provides an important tool and resource for policymakers and the public to better understand and assess the health of the lower St. Johns River basin and make more informed decisions regarding its protection. The analysis covers approximately 100 miles of the river from Welaka to its mouth at Mayport.
Visit www.sjrreport.com to access the entire report and an informative brochure.
Here are some excerpts from the 2012 report:
Lack of Data
Even more than last year, the lack of data has limited our assessment. While the reliability and accuracy of available data is improving with time, the quantity of new data samples for many locations is decreasing. This is a concern, as frequent data collection is required in order to determine whether environmental concerns, such as algal blooms, are linked to trends in water quality parameters. Frequent, long-term data are also needed to evaluate the impact of TMDLs and other management strategies. The number of data samples is on an alarming decrease, with real-time data decreasing most rapidly.
Fecal Coliform Bacteria
The Florida Department of Environmental Protection (DEP) has verified 62 Lower St. Johns River tributaries as impaired for fecal coliform bacteria. While some natural sources exist such as wild birds and mammals, the bulk of the problem has been linked to human sources. Most commonly these sources are from malfunctioning septic systems and sewer problems.
Nutrients
In general, lower phosphorus concentrations have been observed in the main stem of the LSJR as compared to several of the creeks and tributaries; however, all areas sampled have phosphorus concentrations higher than the EPA recommended water quality standard.
Phosphorus and nitrogen inputs from multiple sources should be reduced. Even though the majority of these nutrient concentrations were stable or slightly reduced, maximum concentrations continue to far exceed the EPA recommended standards, particularly in the smaller tributaries and creeks.
Salinity
Over the years, dredging to deepen the channel for commercial and naval shipping in Jacksonville, has led to salt water intrusion upstream. The magnitude of this intrusion over time has not been well quantified. Further deepening is likely to impact salinity regimes that could be detrimental to the grass beds. This is especially important if harbor deepening were to occur in conjunction with freshwater withdrawals for the river.
Submerged Aquatic Vegetation
For the period 2008‑2011, the data showed a declining trend in grass bed parameters – this is in spite of some recovery in grass beds condition in 2011.
Aerial survey observations of manatees and their habitat in Duval County continue to indicate decline in grass bed coverage north of the Buckman Bridge.
Wetlands
The current status of wetlands in Florida is considered UNSATISFACTORY, because a historical decrease in wetlands has been documented statewide. The current status of wetlands in the LSJRB is considered UNCERTAIN, because the reported statewide losses cannot be calculated with certainty for just the LSJRB (Lower St. Johns River Basin).
During the development of this report, it became clear that wetlands data for Northeast Florida are disconnected, incomplete, and have not been recorded with the precision needed to accurately assess trends over time.
Invasive Species
A total of 64 non‑native aquatic species are documented and believed to be established in the LSJRB. There is a high probability that future invasions of non-native aquatic species will occur in the Lower St. Johns River Basin. This study found that the two most significant vectors for transporting non-native organisms were humans and ship ballast, and that both of these vectors are expected to increase in coming years, thereby increasing the likelihood for additional and potentially more frequent introductions.
Chemicals
The LSJR surface waters received 324,000 pounds of chemicals in 2010, mostly nitrates and manganese released by the U.S. Department of Defense and the paper industry. The rate of discharge of chemicals into the LSJR surface waters in 2010 is 7% greater than in 2001 while the rest of the state and US discharged about 10% less since 2001.
Metals
Metals in general have been elevated over natural background levels in sediments all throughout the LSJR for at least two decades and continue to do so today. Nearly all (75 – 91%) of the sediments that were analyzed since 2000 have had concentrations of chromium, zinc, lead, cadmium, or mercury (discussed in more detail below) that are greater than natural background levels (NOAA 2008), sometimes by very large amounts. Sediments in Rice Creek that were analyzed in 2002 had mercury levels that were about 100 times greater than natural background levels. High metal concentrations were found in sediments elsewhere throughout the river, including the Cedar-Ortega system, Moncrief Creek off the Trout River, Broward Creek, and Doctors Lake.