NE Florida Aquatic Preserves - Data Collection at Kingsley Plantation Site 

 Water Quality Summary Report 

 March 2004 – February 2005 

 November 2005 

 Amy Kalmbacher and Eva DiDonato 

In fulfillment of cooperative agreement No. H5310030005 between the Department of 

Interior – National Park Service, Timucuan Ecological and Historic Preserve and the 

Florida Department of Environmental Protection, Office of Coastal and Aquatic Managed 

Areas 
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 Principal investigators: 

 

 Amy Kalmbacher, Environmental Specialist I 

 Florida Department of Environmental Protection 

 CAMA / NE Florida Aquatic Preserves 

 13802 Pumpkin Hill Road 

 Jacksonville, FL 32226 

 904-696-5944 

 amy.kalmbacher@dep.state.fl.us 

 Eva DiDonato, Aquatic Ecologist/ Water Quality Specialist 

 Inventory and Monitoring Program 

 Southeast Coast Network 

 Fort Sumter National Monument 

 1214 Middle Street 

 Sullivan’s Island, SC 29482 

 843-883-5036 

 Eva_DiDonato@nps.gov 

 
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Executive Summary 

The boundaries of the National Park Service (NPS) Timucuan Preserve are nearly 

identical to the boundaries of Florida Department of Environmental Protection’s (DEP) 

Nassau River - St. Johns River Marshes Aquatic Preserve. Toward the close of 2003, 

DEP’s office of Coastal and Aquatic Managed Areas (CAMA) took initial steps toward 

developing a statewide water quality monitoring program involving each of their coastal 

preserves. Since rapid changes due to sedimentation and shifting bathymetry had been 

occurring in the Ft. George River, and because these changes were of concern to the NPS 

and CAMA, our very first data collecting site was designated at Kingsley Plantation. 

In early 2004, funds were transferred to CAMA from the NPS to purchase two Yellow 

Springs Instruments (YSI) Model 6600EDS - S data sondes. These submersible 

instruments record various water quality measurements completely unattended, and are 

designed to continuously collect data at specific intervals for extended deployment 

periods. In January 2004, CAMA staff attached a 24 foot PVC tube directly to one of the 

pilings at the Kingsley Plantation dock to serve as a protective housing for the monitoring 

device. A data sonde was then suspended within the PVC tube and lowered to 

approximately one meter from the bottom of the river, with just the collecting probes 

protruding. From that point on, the instrument has recorded measurements of salinity, 

conductivity, turbidity, temperature, pH, depth and dissolved oxygen every 30 minutes. 

CAMA staff retrieve the meter every 10 to 14 days and replace it with a second meter 

which has been cleaned and calibrated prior to deployment. 

The retrieved data sonde is taken back to the CAMA laboratory where data is 

downloaded from the memory, the unit and the sensors are post-calibrated, cleaned and 

recharged, then stored until the next deployment. As of February 28, 2005 the data sonde 

units completed a full year of data collection at the Kingsley Plantation site. Analysis of 

the data has shown several interesting occurrences. 

After the hurricanes of August/September 2004, the salinity levels in the Ft. George 

River were not only lowered due to large amounts of rainfall, but remained highly 

variable for several weeks thereafter. This prolonged decrease in salinity implies that the 

river and marshes surrounding the area do not flush or exchange waters with the ocean as 

quickly as was previously thought. Because of ever increasing pressure from 

development within the boundaries of this drainage basin, preventative measures to 

control contaminants and nutrient enrichment from surface runoff become more 

important than ever. 

High turbidity levels often coincided with busy boating weekends. The increased amount 

of particulate matter in the water may be the result of increased boating traffic, especially 

at low tides when propellers are more likely to disturb the substrate and suspend silt and 

sand into the water column. 

The data also revealed short periods of time when the dissolved oxygen level fell below 

that of state standards. These low levels do not necessarily indicate a problem within the 
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system, however. Most of these readings occurred during times of high water 

temperature, and can be considered normal for seasonal conditions (warm water does not 

“hold” as much oxygen as cold water). Additionally, these readings were recorded near 

the bottom of the channel where much less surface to air mixing occurs, and dissolved 

oxygen readings are normally lower than elsewhere in the water column. In fact, these 

low oxygen levels may be a natural occurrence that could in some ways be considered 

beneficial to fish populations. During these times of decreased oxygen saturation, 

juvenile fish can forage without fear of predation by larger fish that require greater levels 

of dissolved oxygen and have moved elsewhere to find it. Overall, as long as these 

periods of hypoxia remain limited, the situation should not be viewed as problematic. 

Even though the NPS is no longer funding data collection, CAMA will continue to use 

the Kingsley Plantation monitoring site and partner with the resource staff to share 

research and data beneficial to both. Since this first installation at Kingsley, two 

additional data collectors have been installed at other locations within or immediately 

adjacent to the Timucuan Preserve. At the eventual “build out” of the project, a total of 

four sondes will be placed within the immediate vicinity of Timucuan boundaries. As 

well, two additional sites are planned to the north, one within the Amelia River, and one 

within the Ft. Clinch State Park Aquatic Preserve. As the project continues, and collected 

data are analyzed, it is hoped that we will gain additional insight into the varied tidal 

systems that comprise our preserves, and continue to share information to the benefit of 

all who enjoy this unique area of Florida. 
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2) Research Objectives: 

 The Ft. George River, in Northeast Florida’s Nassau River basin, connects the 

Intracoastal Waterway with the Atlantic Ocean at Ft. George River Inlet. Ongoing 

sedimentation and reduced tidal volume due to hydrological changes in this inlet have led 

to questions concerning potential water quality changes. For this reason Kingsley 

Plantation (NPS Timucuan Ecological and Historic Preserve), situated on the south bank 

of the Ft. George River, was chosen as a monitoring site for a YSI 6600 EDS-S data 

sonde. 

 
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 Historic data does exist for this system, but it is somewhat sporadic and mostly 

derived from grab samples taken at widely spaced intervals. To date nothing has been 

available that is equivalent to the type of data collected by the YSI 6600 EDS-S data 

sonde. The instrument collects continuous readings on a half hour cycle during 

deployments averaging 11 days in length. At the conclusion of the deployment the sonde 

is retrieved and exchanged for a clean, newly calibrated unit. In this way there is a 

constant, unbroken recording of data, and therefore a much higher rate of consistency in 

the resultant tables and graphs. 

 The objectives of this project are as follows : 

1) to create a point in time baseline of water quality measurements against which to 

detect and measure future alterations to the system 

2) to detect any deviations from expected water quality measurements 

3) to detect any variation from state water quality standards 

4) to relate observed variations in water quality measurements with concurrently 

collected meteorological data 

3) Research Methods: 

 

 A YSI 6600 EDS-S data sonde has been continuously operating (collecting data every 

30 minutes) at the Kingsley Plantation dock site since January 20, 2004. Since operating 

this type of extended deployment instrumentation was new to staff, the month of 

February essentially served as a “break in” period for data sonde operation and rotation. 

Though data was collected during February, it is not included in this report, and for all 

intents and purposes March 1, 2004 is considered the official start of data collection. 

 

 Data sonde housing attached to piling at NE corner of Kingsley Plantation dock. 
7

The sonde is housed within a vertical 4 inch diameter PVC pipe that is directly attached 

to one of the support pilings at the NE corner of the Kingsley Plantation dock. The sonde 

is lowered on an attached rope within the PVC tube until its probes are just barely 

exposed beyond the lower edge of the pipe. At this point it is suspended approximately 

one meter above the substrate. A sheet of plastic mesh (1/4 inch opening) surrounds the 

protective guard on the data sonde to prevent fish and crabs from entering the guard and 

damaging any of the probes. A locking cap on the dock end of the PVC tube prevents any 

unwanted tampering, and a 4 inch stainless steel carriage bolt below the submerged edge 

prevents accidental slippage out of the other end should the rope or attachment hardware 

fail. Exchange of the data sondes (replacing an operating unit for a clean, calibrated unit 

at the end of a deployment period) usually takes about 5 - 10 minutes. Retrieval and 

replacement of the sondes never occurs within 5 minutes of a scheduled data recording in 

order to assure continuous collection of information. Field notes are also recorded during 

the exchange regarding weather conditions, tidal stage, condition of the retrieved sonde, 

and any unusual occurrences at the site. 

 

 Richard Bryant, Chief of Resources Stewardships for the NPS Timucuan Preserve, with a YSI 

6600EDS-S data sonde. 
8

After retrieval from the sampling site, data sondes are returned to the laboratory where 

post deployment readings and reconditioning take place in accordance with methods 

outlined in the YSI Operating and Service Manual. The sonde is rinsed with tap water 

then sequentially submersed in each of the various standards in order to obtain post 

deployment readings. Standards consist of pH (Fisher Scientific 7.00 buffer solution), 

conductivity (Exaxol 50.00 mS/cm standard) and 0.0 NTU turbidity (distilled water). The 

dissolved oxygen membrane, if requiring replacement, can also be exchanged at this 

point, as a period of at least 24 hours is required for it to equilibrate before its next 

deployment. These post deployment readings are then used to evaluate the validity of the 

data collected for that deployment period. 

4) Site location and character: 

 Ft. George River Inlet is approximately 6 miles south of Nassau Sound and 

immediately north of the mouth of the St. Johns River in Northeast Florida’s Duval 

County. The inlet is bordered by Little Talbot Island to the north, and Ward’s bank to the 

south, and is one of the few inlets left in the state that is not hardened with fortification 

structures. Much of the land surrounding this system has remained relatively undeveloped 

due to its ownership by various governmental entities and its intended use for 

conservation and low impact public recreation. 

 Ft. George River connects to Simpson Creek a little more than a mile and a half from 

its mouth, and then another mile and a half to the west, it joins the Intracoastal waterway 

which in turn flows north to the mainstem of the Nassau River. The surface area drained 

by this sub – basin of the Nassau River constitutes an area of approximately 6,285 acres 

(Adamus et.al., 1997). As a conveyance of surface water runoff, this is not one of the 

largest freshwater contributors to the nearly 55 mile long Nassau River. The Ft. George 

River drainage basin is a sizable system, however, and any major changes to it could 

exert a noticeable impact on the Nassau River as well. 

 The climate for the Ft. George Island area can be categorized as humid and subtropical with long summers of abundant rainfall, followed by comparatively dry winters 

and occasional frost. The average annual rainfall is approximately 53 inches, at least 50% 

of which occurs during the months of June through September. Data from weather 

stations in Jacksonville and Jacksonville Beach give the average yearly temperature for 

this area as 69 degrees, with 55.9 degrees as the lowest mean monthly temperature in 

January, and 82.6 as the highest mean monthly temperature in July. Prevailing winds in 

this coastal area tend to be out of the east and southeast throughout the summer months, 

and predominantly out of the northeast during the winter. 

 
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 View from Kingsley Plantation dock looking west along Ft. George River 

 

 Station description: The Kingsley Dock (KD) site is located at the Kingsley Plantation 

boat dock (N 30° 44’ 11.6” / W 81° 43’ 9.08”) within the NPS Timucuan Ecological and 

Historic Preserve on Ft. George Island. Surrounding land use is predominantly natural 

with very limited residential development on Ft. George Island and the neighboring 

Talbot Islands. This site and surrounding surface waters carry the dual designation of 

Class II Shellfish Harvesting Waters and Outstanding Florida Waters. The average depth 

at this site is 4.0m with a tidal range of 1.54 m; the substrate type is muddy sand, with 

emergent oyster beds lining the immediate shoreline. 

5) Entry verification: 

 Data are collected with a YSI Model 6600EDS-S data sonde and uploaded to a laptop 

PC in the water quality lab at the NE FL Aquatic Preserve office. Version 3.15 of Eco 

Watch software is used to plot the data and generate graphs. Graphs for each deployment 

are studied immediately for trends and anomalies. Any unusual variations are then noted 

as pertaining to individual probes, and the need for their reconditioning or replacement. 

 Each data file is exported as a comma delimited file (.cdf) using EcoWatch software. 

Two copies of this .cdf file are saved in the .csv format. One is used to archive the raw 

data, and one is edited to adjust all records of Eastern Standard Time to read exactly on 

the hour or half hour. This second file is also used to delete data at the beginning and end 

of each deployment period when the instrument was out of the water. These unwanted 

data can be identified, and consequently deleted, due to field notes that document the start 

and end times for each deployment, and from conductivity and depth readings near zero. 
10

 Monthly data files are then created from the edited .csv files and processed by various 

macros distributed by the Centralized Data Management Organization (CDMO) which 

handles all data sonde data collected by the National Estuarine Research Reserves 

(NERR). The macros check files for missing data points, fill all cells that do not contain 

data with periods, and convert the data columns to CDMO approved formats for time, 

date and numeric values. They also find all data that are out of acceptable range for the 

sensors, save the files as Excel worksheets, and generate single parameter monthly 

graphs. 

 Questionable data are evaluated to determine if they can be deemed valid, or must be 

deleted. Data that have fallen either outside of the expected range for the given site or 

outside of the range of measurements established for the data sonde sensors are flagged 

(see Table 1). Anomalous data are investigated for validity based on field observations, 

weather data, quality control checks, and instrument diagnostics. If anomalies are 

attributed to sensor malfunction, they are deleted. These deletions can be the direct result 

of a physical defect in one of the data sonde probes, such as a DO membrane puncture or 

a ruptured pH sensor “bulb”. If the voltage reading of the probe is outside of the range 

established for the sensor, or if the sensor will not calibrate, data will also be deleted. 

 

6) Data collection period: 

 

 Though the data sonde protective housing was installed at the Kingsley Plantation 

dock in mid January of 2004, and the first data sonde unit was placed in the housing by 

the end of that month, data for this study was not collected until March 1, 2004. The 

month of February was used as a “break in period” in terms of familiarization with sonde 

calibration, deployment, data handling, and any possible trouble shooting for problems 

that might arise in the initial phase of the project. Since March 1, 2004, however, the 

station has remained in continuous service. Individual data sonde deployment and 

retrieval times for the full year of study from 03/01/04 – 02/28/05 are as follows: 

BEGAN ENDED 

02/26/04 16:00 03/11/04 15:00 

03/11/04 15:30 03/30/04 14:00 

03/30/04 14:30 04/08/04 13:00 

04/08/04 12:30 04/22/04 13:30 

04/22/04 14:00 05/06/04 12:00 

05/06/04 12:30 05/21/04 14:00 

05/21/04 14:30 06/04/04 11:30 

06/04/04 12:00 06/11/04 12:00 

06/11/04 13:00 06/22/04 09:00 

06/22/04 09:30 07/01/04 12:30 

07/01/04 13:00 07/09/04 10:00 

07/09/04 10:30 07/16/04 14:30 

07/16/04 15:00 07/26/04 09:30 

07/26/04 10:00 07/28/04 10:30 
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07/28/04 11:00 08/04/04 09:30 

08/04/04 10:00 08/16/04 11:00 

08/16/04 11:30 08/24/04 10:30 

08/24/04 11:00 08/31/04 12:00 

08/31/04 12:30 09/08/04 13:00 

09/08/04 13:30 09/21/04 11:00 

09/21/04 10:30 09/29/04 11:30 

09/29/04 11:00 10/06/04 12:00 

10/06/04 12:00 10/13/04 11:30 

10/13/04 12:00 10/25/04 11:30 

10/25/04 12:00 11/05/04 11:00 

11/05/04 11:30 11/15/04 10:30 

11/15/04 11:30 11/30/04 12:30 

11/30/04 13:00 12/14/04 10:30 

12/14/04 11:00 12/30/04 12:30 

12/30/04 12:00 01/13/05 11:30 

01/13/05 12:00 01/28/05 16:00 

01/28/05 16:30 02/22/05 11:30 

02/22/05 12:00 03/09/05 11:00 

7) Distribution

 Since the establishment of the initial monitoring site at Kingsley Plantation the NE 

Florida Aquatic Preserves office has expanded its program to include two other stations 

within the Nassau/ St. Johns River drainage basins that also collect continuous data. After 

being downloaded, checked and graphed, the data are stored (for the time being) within 

the NE FL Aquatic Preserve office. Until available in a more broadly accessible format, 

data from all three sites are available upon request to other agencies, universities, nonprofit environmental organizations, independent researchers and the general public. 

 In response to such requests for data from the Kingsley Plantation site for the first 

year of collection, the NPS Timucuan Ecological and Historic Preserve and DEP/CAMA 

Northeast Florida Aquatic Preserves retain the right to be fully credited for having 

collected and processed the data. The user is also to contact and fully acknowledge both 

NPS and DEP/CAMA in any subsequent publications in which any part of the data is 

used. 

8)Associated researchers and projects:

 

 CAMA’s’ Northeast Florida Aquatic Preserves office, aside from coordinating with 

other sections within the Department of Environmental Protection, works cooperatively 

with other resource protection agencies and organizations in the Nassau and St. Johns 

Rivers watershed. Some of these include the: 1) National Park Service (NPS), 2) St. 

Johns River Water Management District (SJRWMD), 3) US Army Corp. of Engineers 

(USACOE), 5) City of Jacksonville (COJ), 6) The Nature Conservancy (TNC), 7) DEP 
12

Division of Parks and Recreation (FPS), 8) Florida Fish and Wildlife Conservation 

Commission (FWCC), and 9) US Fish and Wildlife Service (USFWS). 

 Although occurring just slightly behind schedule to coincide with the most recent 

phase, the current monitoring program is producing data that may be of assistance for the 

next cycle of DEP’s Total Maximum Daily Load program for the Nassau River. The 

existing sampling sites are located within segments of the river that do not have abundant 

background or historic information, and additional sites are planned for the near future. 

This type of continuous data may help give staff a clearer picture of conditions within 

certain stretches of the Nassau River and therefore assist in regulatory determinations. 

 The City of Jacksonville’s Ambient Water Quality Section monitors the Ft.George 

River bi-monthly in its 12 site monitoring program within the Timucuan Preserve. 

Though not sampling all of the same parameters as the COJ, the aquatic preserve’s 

program can offer continuous data from sites within the same region. In so doing, the 

city’s long running program may be bolstered with information of prevailing conditions 

surrounding the collection of their “grab” samples that require laboratory analysis. 

 In cooperation with Richard Bryant, Chief of Resources Stewardships for the NPS 

Timucuan Preserve, approximately a dozen photo points have been established around Ft. 

George Inlet in attempts to document rudimentary changes in flow and channel 

morphology. In lieu of aerial photos that would be preferable (albeit economically 

unfeasible), the photos help record physical conditions at the time of the sonde’s water 

quality data collection. Taken quarterly, usually at the lowest possible tide stage during a 

given season, it is hoped that these photos coupled with the collected data will give a 

better overall view of what has been occurring, hydrologically, in the Ft. George River 

Inlet. 

9) Variable Sequence, Range of measurements, Units, Resolution, and Accuracy

Variable Range of Measurements Resolution Accuracy 

Date 1-12, 1-31, 00-99 (Mo,Day,Yr) 1mo, 1 day, 1 yr NA 

Time 0-24, 0-60, 0-60 (Hr, Min, Sec) 1 hr, 1 min, 1 sec NA 

Temp -5 to 45 (c) 0.01 C +/- 0.15C 

Sp Cond 0-100 (mS/cm) 0.01 mS/cm +/- 5% of reading+0.001mS/Cm 

Salinity 0-70 Parts per thousand (ppt) 0.01ppt +/-1% of reading or 0.1ppt * 

DO 0-200(% air saturation) 0.1%@ air sat +/-2% @ air saturation 

DO 200-500 (% air saturation) 0.1% @ air sat +/-6% @ air saturation 

DO 0-20 (mg/l) 0.01 mg/l +/-0.2 mg/l 

DO 20-50 0.01 mg/l +/- 0.6 mg/l 

Depth 0-9.1 (m) 0.00m +/-0.018m 

PH 2-14 units 0.01 units +/- 0.2 units 

Turbidity 0-1000 NTU 0.1 NTU +/- 5% of reading or 2 NTU * 

Whichever is greater * 
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FOR COMPLETE SETS OF TABULAR AND GRAPHED DATA - 

SEE APPENDICES A AND B 

10) Coded variable indicator and variable code definitions: 

Within the data sets (appendices A and B) the following definitions apply: 

File definitions: YSI deployment site/month/year (e.g. KDWQ0404 = monthly data from 

the Kingsley Plantation dock site for April of 2004). 

Site code: KD = Kingsley Dock 

11) Anomalous data (Contained within appendices A and B): 

Note 1: When data sonde units are exchanged in the field, sometimes there are slight 

shifts produced in the data that are observable in the monthly graphs. These shifts are 

most notable in pH, specific conductivity, DO% and DO concentration and may be 

related to sensor drift (due to fouling) and /or calibration/performance difference 

between sondes. 

Note 2: Turbidity “outliers” (i.e., those values that are negative or greater than1000NTU) 

are listed separately in Table 1 and have not been deleted from the monthly records. 

Negative turbidity values have occurred throughout the sampling year, but have been 

within the accuracy range of the sensor (+/- 2.0 NTU) and therefore have not been 

removed from the dataset. 

March 1- 31, 2004 

 

a) 03/28/04 –03/29/04 Accelerated winds from the north to northeast during these days 

may have affected depth, salinity, conductivity, and dissolved oxygen readings. 

b) 03/30/04, 14:30 Shift in DO, conductivity, salinity, and depth attributed to data 

sonde exchange. 

April 1 – 30, 2004 

 a) 04/08/04, 12:30 Shift in salinity and specific conductivity due to exchange of data 

sonde. 

b) 04/13/04 & 04/14/04 Salinity and specific conductivity shift coincide with rainfall 

data for Kingsley area on those days (> .5 inch). 
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 c) 04/30/04, 14:00, 1430, 19:30 Sudden occurrence turbidity spike to 1621 NTUpossible obstruction (fish or crab inside protective “cage”) or beginning of growth on 

probe toward end of deployment. 

May 1 – 31, 2004 

a) 05/01/04 – 05/04/04 Salinity, specific conductivity, pH and DO affected by nearly 2 

inches of rainfall during the first four days of the month. 

 

b) 05/03/04 – 05/05/04 High turbidity readings most likely due to end of deployment 

fouling. 

c) 05/31/04 Moderately high turbidity readings could possibly be due to holiday 

(Memorial Day) boat traffic, though very high turbidity spikes are most likely attributed 

to heavy fouling at the end of deployment – filamentous growth had to be removed from 

probe at post calibration. 

June 1 – 30 , 2004 

a) 06/01/04 – 06/03/04 Turbidity values high due to heavy fouling at end of 

deployment (see above). 

b) 06/11/04, 13:00 Shift in salinity and specific conductivity appear related to data 

sonde exchange 

c) 06/12/04 – 06/15/04 Salinity and specific conductivity readings reflect the 

approximate 2 inches of rainfall that occurred during this time. 

d) 06/29/04, 12:30, 20:00 High turbidity spikes probably due to obstruction (fish or 

crab within mesh guard). 

July 1 – 31, 2004 

 

a) 07/01/04 Turbidity spike to near 70NTU appears to be related to end of deployment 

fouling. 

b) 07/12/04 – 07/20/04 Downward shift in salinity and specific conductivity reflective 

of rainfall (approximately 2 1/3 inches). 

c) 07/20/04 – 07/26/04 DO readings suspect – O-ring from probe found on bottom of 

protective “cage” upon retrieval. 
15

August 1 – 31, 2004 

a) 08/14/04 – 08/25/04 Decrease in salinity / specific conductivity readings correspond 

with rainfall data for this period. 

September 1 – 30, 2004 

a) 09/05/04, 09/29/04 Turbidity spikes to 100NTU and over, and general exaggeration 

of values during the month, appear to be legitimate and associated with hurricane activity 

b) 09/08/04 – 09/20/04 Salinity and specific conductivity decrease in response to 

hurricane related rainfall (nearly 5 inches on 09/05, 3 inches on 09/14 and 09/15, and 3 1⁄2 

inches on 09/27) 

c) 09/20/04 Beginning of a depth shift most likely associated with strong NE winds 

from hurricane Ivan. 

October 1 – 31, 2004 

10/27/04, 5:00 Isolated turbidity spike to 862 NTU – probably due to obstruction. 

November 1 – 30, 2004 

a) 11/13/04 – 11/15/04 Elevated turbidity readings and spike to over 50 NTU 

attributed to fouling at end of deployment. 

b) 11/09/04 Beginning of a period of strong winds out of the E/NE causing a “stacking 

up” effect reflected in depth, salinity and specific conductivity readings. 

December 1 – 31, 2004 

a) 12/26/04 Slightly elevated turbidity associated with over 1 1⁄2 inch of rainfall in 

vicinity. 

b) 12/20/04 Temperature drop and isolated downward spike in salinity and specific 

conductivity (?) – can not attribute to rainfall, but strong W/NW winds on the evening of 

the 19th and early morning hours of the 20th may have influenced readings. 

January 1 – 31, 2005 

a) 01/12/05, 01/15/05, 01/16/05, 01/28/05 – 01/30/05 Slightly elevated turbidity 

readings - all seem legitimate, and those occurring at mid- month associated with rainfall. 
16

b) 01/13/05, 12:00 and 01/28/05, 16:30 Sharp drops in DO readings attributed to data 

sonde exchanges and calibration differences between units. 

c) 01/15/05 – 01/18/05 Depth , salinity, and specific conductivity increases and 

temperature decreases correspond with strong N/NE winds. 

February 1 – 28, 2005 

a) 02/16/05 – 02/22/05 Salinity, specific conductivity, depth, and pH readings exhibit 

downward trend corresponding to prevailing westerly winds during the first few days of 

this period. 

12) Deleted Data: 

 Values were recorded for the following periods by the data sondes, but removed from the 

final data set for the reasons stated. 

 

- 03/11/04, 15:30 – 03/13/04, 7:00 – data sonde hung up in tube, not deployed to full 

sampling depth 

- 06/03/04, 12:00 – 06/04/04, 10:30 Retrieval of data sonde was attempted on 06/03 but 

it became wedged in tube well above sampling level. Unit could not be removed from 

the tube until the following day at noon – all subsequent readings were recorded at an 

elevated depth. 

-08/04/04 , 10:00 – 08/05/04, 4:00 Data sonde hung up in tube – not deployed to proper 

sampling depth 

-11/15/04, 11:30 – 11/16/04, 13:00 Very high tide waters prevented data sonde from 

settling to its proper depth 

13) Missing Data: 

Data are missing due to equipment or associated specific probes not being deployed, 

equipment / battery failure or time set errors at calibration. 

- 05/07/04, 2:30 No value was recorded for specific conductivity (?) – no explanation 

for this missed reading. 

- 06/04/04 11:00, 11:30 No values recorded – time set problem during data sonde 

exchange. 

- 06/22/04 9:30, 10:00 No values recorded – Time set problem during data sonde 

exchange. 
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- 07/03/04, 8:00 – 07/09/04, 10:00 No data recorded – flooded battery chamber. 

- 07/16/04, 14:00 and 14:30 No values recorded – time set error, not set to EST 

- 07/26/04 , 10:00 No values recorded – time set error at deployment 

- 08/16/04, 11:30 No values recorded – time set error at time of data sonde exchange 

- 10/06/04, 11:30 No values recorded time set error at deployment 

Table 1. Turbidity outliers 

 Date Time Value 

04/30/04 14:00:00 1620 

04/30/04 14:30:00 1616 

05/03/04 18:30:00 1609 

05/04/04 00:30:00 1610 

05/04/04 02:30:00 1606 

05/04/04 20:00:00 1598 

05/04/04 20:30:00 1191 

05/04/04 21:00:00 1597 

05/04/04 21:30:00 1597 

05/04/04 23:00:00 1600 

05/04/04 24:00:00 1600 

05/05/05 00:30:00 1598 

05/05/05 02:00:00 1597 

05/05/05 04:30:00 1595 

05/05/05 20:00:00 1609 

05/31/05 06:30:00 1816 

05/31/05 09:00:00 1840 

05/31/05 10:30:00 1779 

05/31/05 13:00:00 1850 

05/31/05 15:30:00 1860 

05/31/05 17:00:00 1520 

05/31/05 19:30:00 1812 

05/31/05 22:00:00 1846 

05/31/05 22:30:00 1111 

05/31/05 24:00:00 1847 

06/01/05 00:30:00 1039 

06/01/05 02:30:00 1746 

06/01/05 03:00:00 1054 

06/01/05 05:00:00 1025 

06/01/05 05:30:00 1344 

06/01/05 08:30:00 1356 
18

06/01/05 09:00:00 1663 

06/01/05 11:00:00 1700 

06/01/05 11:30:00 1103 

06/01/05 14:00:00 1818 

06/01/05 16:00:00 1474 

06/01/05 16:30:00 1211 

06/01/05 19:00:00 1091 

06/01/05 19:30:00 1806 

06/01/05 22:30:00 1831 

06/02/05 02:30:00 1534 

06/02/05 05:00:00 1338 

06/02/05 05:30:00 1558 

06/02/05 09:00:00 1761 

06/02/05 09:30:00 1037 

06/02/05 12:00:00 1841 

06/02/05 15:00:00 1851 

06/02/05 18:30:00 1802 

06/02/05 22:00:00 1802 

06/03/05 08:30:00 1799 

06/03/05 12:00:00 1822 

06/03/05 12:30:00 1077 
19

14) Kingsley Data Summary:

Salinity: 

• Mean Daily Salinity = 29.4 ppt 

• Mean Salinity Range = 7.75 ppt 

• Lowest Salinity during this year occurred in September immediately after 

Hurricane Francis (5.2 ppt). 

• Highest Salinity during this year occurred in March (35.9 ppt). 

Salinity (ppt)

00.0

05.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

3/1/2004

4/1/20045/1/2004

6/1/2004

7/1/2004

8/1/2004

9/1/2004

10/1/2004

11/1/2004

12/1/2004

1/1/2005

2/1/2005

Sal (ppt)

0

5

10

15

20

25

30

35

40

March 2004

April 2004

May 2004

June 2004

July 2004

August 2004

September 2004

October 2004

November 2004

December 2004

January 2005

February 2005

Salinity (ppt)

Ma ximum

10th %tile

Mean

90th %tile

Minimum
20

Turbidity: 

• Greater then 25 NTU was experienced around 3% of the time. 

• Large spike in turbidity over Memorial Day weekend. 

• Minimum and maximum turbidities were 0.1 NTU and 1,860.2 NTU respectively. 

Turbidity (NTU)

0.0

200.0

400.0

600.0

800.0

1000.0

1200.0

1400.0

1600.0

1800.0

2000.0

3/1/2004

4/1/2004

5/1/2004

6/1/2004

7/1/2004

8/1/2004

9/1/2004

10/1/2004

11/1/2004

12/1/2004

1/1/2005

2/1/2005

Turb (NTU)

0

40

80

120

160

200

March 2004

April 2004

May 2004

June 2004

July 2004

August 2004

September 2004

October 2004

November 2004

December 2004

January 2005

February 2005

Turbidity (NT

U

Ma ximum

10th %tile

Mean

90th %tile

Minimum
21

* Depth: 

• Mean daily depth range = 1.54m. 

• Mean depth = 4.0m. 

• Minimum recorded depth was 1.6m (December), and maximum was 4.4m 

(November). 

Water Depth (m)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

4.50

5.00

3/1/20044/1/20045/1/2004

6/1/2004

7/1/20048/1/2004

9/1/2004

10/1/200411/1/2004

12/1/2004

1/1/20052/1/2005

Depth (m)

*All depth values represent the data sonde’s depth in the water column, not the actual 

depth of the river. River depth at the time of collection of any of these values would be 

that number plus one meter. 

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

March 2004

April 2004

May 2004

June 2004

July 2004

August 2004

September 2004

October 2004

November 2004

December 2004

January 2005

February 2005

Water Depth (m)

Ma ximum

10th %tile

Mean

90th %tile

Minimum
22

Water temperature: 

• Water temperatures ranged from 9.7 C to 30.9 C. 

• Temperatures exceeded 25 C in 40% of the measurements. 

Water Temperature (°C)

00.0

05.0

10.0

15.0

20.0

25.0

30.0

35.0

3/1/2004

4/1/2004

5/1/2004

6/1/2004

7/1/20048/1/2004

9/1/2004

10/1/2004

11/1/2004

12/1/2004

1/1/2005

2/1/2005

Temp (°C)

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

March 2004

April 2004

May 2004

June 2004

July 2004

August 2004

September 2004

October 2004

November 2004

December 2004

January 2005

February 2005

Temperature (°C)

Ma ximum

10th %tile

Mean

90th %tile

Minimum
23

pH: 

• Values greater then 8.0 occurred 21% of the time 

• Values ranged from 7.2 – 8.2. 

pH

6.60

6.80

7.00

7.20

7.40

7.60

7.80

8.00

8.20

8.40

3/1/2004

4/1/2004

5/1/2004

6/1/2004

7/1/20048/1/20049/1/2004

10/1/2004

11/1/2004

12/1/2004

1/1/20052/1/2005

pH

7.0

7.2

7.4

7.6

7.8

8.0

8.2

8.4

8.6

March 2004

April 2004

May 2004

June 2004

July 2004

August 2004

September 2004

October 2004

November 2004

December 2004

January 2005

February 2005

p

H

Ma ximum

10th %tile

Mean

90th %tile

Minimum
24

DO %: 

• Minimum percent DO saturation observed was 5.4% (July). 

• Highest percent DO saturation observed was 139.3% (January). 

Dissolved Oxygen (% Saturation)

0.0

20.0

40.0

60.0

80.0

100.0

120.0

140.0

160.0

3/1/20044/1/2004

5/1/20046/1/2004

7/1/2004

8/1/2004

9/1/2004

10/1/2004

11/1/2004

12/1/2004

1/1/20052/1/2005

DO%

0

20

40

60

80

100

120

140

160

March 2004

April 2004

May 2004

June 2004

July 2004

August 2004

September 2004

October 2004

November 2004

December 2004

January 2005

February 2005

Dissolved Oxygen (% saturation)

Ma ximum

10th %tile

Mean

90th %tile

Minimum

 

 Graphs based on data collected from the first 48 hours of each deployment
25

Class II Surface Water Quality Standards: 

 The Florida Department of Environmental Protection has designated present and 

future most beneficial uses of all waters of the State by means of a classification system 

set forth in Chapter 62-302 of the Florida Administrative Code. Outlined in this chapter 

are surface water quality standards that have been established by the Department as a 

means for the protection and propagation of fish, shellfish, and wildlife, as well as for 

recreation in and on the water. According to Chapter 62- 302, all waters from Ft. George 

Inlet north to Nassau Sound, including all of Ft. George River and Simpson Creek, are 

categorized as Class II waters (shellfish propagation or harvesting waters). In terms of 

standards for Class II waters, only three parameters collected for this survey could be 

considered applicable: pH, dissolved oxygen, and turbidity. Florida state standards for 

each of these parameters are as follows: a) pH: Shall not vary more than one unit above 

or below natural background of coastal waters or more than two-tenths unit above or 

below natural background of open waters provided that the pH is not lowered to less than 

6.5 units or raised above 8.5 units. (Full definition contained in Section 62-302.502 (3) 

F.A.C.) . b) Dissolved Oxygen: The average for a 24 hour period shall not fall below 5 

mg/l, shall never be less than 4 mg/l, and normal daily and seasonal fluctuations above 

these levels shall be maintained. c) Turbidity: Levels must not exceed 29 NTU over 

natural background conditions. 

a) pH: Recorded pH values for the entire year fell within the expected range 

considering historic data for this region, and within bounds of state standards 100% of the 

time. Values collected at this site ranged from a minimum of 7.2 to a maximum of 8.2. 

b) Dissolved oxygen: State standards are difficult to apply in this situation as it is 

very common in tidal creeks of this region for dissolved oxygen levels to dip below 

standard values during the summer months. It does not necessarily signal a problem, 

however, when such levels are encountered at the Kingsley site and several factors should 

be kept in mind when trying to apply the standards. In general, warm water cannot attain 

the oxygen saturation level that the same volume of colder water can. In essence, cold 

water “holds” more oxygen than warm water does. Thus during the extreme temperatures 

experienced in northeast Florida during summer months, an occasional low dissolved 

oxygen condition is almost to be expected. Additionally, dissolved oxygen values for this 

report were recorded at approximately one meter above the substrate where there is little 

surface to air mixing. Presumably values would increase if readings were taken elsewhere 

in the water column – readings near the bottom often represent “worst case scenario” for 

dissolved oxygen levels. Lastly, and in terms of immediate effect upon resident species, 

large fish that are most acutely affected by these lowered levels compensate by moving 

off to more oxygen saturated waters. In some respects, this can benefit populations of 

smaller species and juveniles in that predation may markedly decrease during periods of 

high temperature and low dissolved oxygen. Rather than create elevated concern over 

“fitness” of habitat, deviation from state standards may simply indicate the need for 

continued monitoring and perhaps invite investigation into the applicability of the 

standard itself in these types of estuarine environments. 

 Using an earlier model of the YSI 6600, the National Estuarine Research Reserves 

(NERR) showed an increase of hypoxia (conditions where dissolved oxygen values fall 
26

below 28% saturation) with increasing deployment duration (Wenner et al. 2004). To 

compensate for this finding and minimize bias due to drift it was recommended that 

analysis of dissolved oxygen data be based only on the first 48 hours of deployment. 

Currently a newer model of the YSI is being used (YSI 6600EDS-S). The YSI 6600EDSS model is equipped with a sweeping brush that clears the surface of the probes every 

five minutes in order to address the biofouling issue. To our knowledge a new 

recommendation for deployment duration with regards to the YSI 6600EDS-S and 

dissolved oxygen data has not been made. Until the time either the NERR program or 

NPS have sufficient data to determine the new deployment duration for reliable DO data, 

it has been decided to continue to use data only from the first 48 hours of deployment for 

DO analyses. In doing this we are guaranteed an unbiased estimate of DO in the system. 

However, for the purpose of this report the full set of data is being made available. 

Graphic depictions of the data have been identified as to which graph was created with 

which set of data (the complete set or the “48 hour” set). Gaps appear in the monthly data 

graphs (Appendix B) where there was suspect or missing data. 

 Throughout the sampling year, the minimum percent DO saturation observed was 

5.4% (July) and the highest was 139.3% (January). As for actual percentages in terms of 

“failure” to meet state standards for dissolved oxygen levels throughout the duration of 

the year, readings fell below the 4mg/l level 9.4% of the time when only the first 48 

hours of data was used, and 7.0% of the time when all of the data was used. When 

calculating for the less than 5mg/l average in a 24 hour period, using just the data from 

the first 48 hours of each deployment, the result was 7.2% of the time. The value for this 

average using all available data was 9.7%. [The preceding graph depicts dissolved 

oxygen data for the entire year by percent saturation. This is a measurement that 

compensates for temperature variation. State standards for dissolved oxygen do not 

incorporate this type of compensation and are expressed in mg/l as opposed to percent 

saturation.] Not surprisingly, July and August were months with the lowest values - there 

were periods when the average did not rise above 5mg/l for several days (as can be seen 

on the monthly graphs in Appendix B). 

c) Turbidity: This standard was created under the assumption that there is the 

presence of some type of effluent or spill coming from a distinct source. Under these 

circumstances, it is possible for one sample to be taken in the affected area, and a second 

“control” or background sample to be taken upstream and away from the effluent. In this 

particular situation, where turbidity is just being measured against conditions over time, 

the standard is not as easily applied. 

 Minimum and maximum turbidities during the sampling year were 0.1 NTU and 

1860.2 NTU respectively. In order to answer the question of how often Class II turbidity 

standards were exceeded, (after acknowledging that the standards do not truly apply in 

the same manner as written) calculations were made to approximate 

“background”conditions. First, an average of all turbidity values falling between the 10th

and 90th percentile for the entire year was determined (7.96 NTU), then increased by 29 

NTU (36.96 NTU). At this point, monthly tables for turbidity values were checked for the 

number of times readings exceeded this amount. After the final calculations, it appears 

that the “29 NTU above background” standard was only exceeded 1.9% of the time. 

Instances of high readings or turbidity “spikes” appear mostly isolated and are more often 

attributed to end of deployment biofouling of the probe than anything else. Occasions of 
27

generally elevated turbidity readings were noted during some weekends, perhaps linked 

to increased boat traffic around the dock. This may have been the case during the 

Memorial Day holiday. However, this time also coincided with the end of a sonde 

deployment cycle so direct cause is not clear. 

15) Post deployment information: 

Table 2. Post deployment readings for all data sondes deployed at the Kingsley 

Plantation site from March 2004 – Feb . 2005 

Date pH Temp.(C) SC(mS/cm) DO% Turbidity (NTU) Depth(m) 

03/11/04 7.04 19.31 36.77 102.5 0.0 0.108 

03/30/04 7.06 22.29 38.52 98.3 0.2 -0.111 

04/08/04 * 24.98 34.90 96.4 0.0 -0.122 

04/22/04 7.04 22.78 50.17 102.9 0.1 0.100 

05/06/04 6.94 22.26 49.56 104.7 4.1 0.016 

05/21/04 6.95 23.09 45.06 99.3 0.4 0.008 

06/04/04 7.03 23.10 48.86 99.9 0.0 -0.055 

06/11/04 6.99 24.03 50.34 95.7 0.4 - 0.062 

06/22/04 7.03 24.29 49.73 101.1 -0.2 0.011 

07/01/04 7.05 24.67 49.75 99.5 0.1 0.059 

07/09/04 7.01 23.55 50.17 99.0 0.0 -0.006 

07/16/04 7.00 23.50 49.18 103.5 0.2 -0.088 

07/26/04 7.03 24.39 50.59 96.8 0.0 0.075 

07/28/04 6.98 24.12 49.83 100.1 0.0 -0.034 

08/04/04 6.97 24.78 50.04 72.5 - 0.5 -0.031 

08/16/04 7.04 23.65 50.12 102.9 0.8 0.104 

08/24/04 6.89 23.92 50.49 95.0 0.1 -0.049 
28

09/08/04 7.03 24.08 50.36 104.2 0.4 -0.317 

09/21/04 6.97 23.97 50.34 101.4 0.0 0.082 

09/29/04 6.90 23.99 49.96 89.8 -0.2 -0.066 

 

10/06/04 6.96 23.28 50.75 99.4 0.5 0.139 

10/13/04 7.11 23.46 50.12 93.8 -0.5 -0.177 

10/25/04 7.05 22.64 50.20 99.1 -0.1 0.084 

 

11/05/04 7.01 21.12 49.74 107.5 0.1 -0.016 

11/15/04 7.06 21.38 49.74 107.6 0.0 0.041 

11/30/04 7.03 21.22 47.98 107.6 0.0 -0.142 

12/14/04 7.05 19.67 49.87 104.3 0.2 0.115 

12/30/04 7.07 19.80 49.59 104.3 0.1 0.038 

01/13/05 7.03 22.83 50.48 102.1 3.9 - 0.151 

01/28/05 7.03 20.96 50.27 102.1 0.0 0.321 

02/22/05 7.08 21.77 50.40 105.5 0.0 -0.097 

03/09/05 7.06 19.63 50.31 100.6 -0.8 -0.062 

* pH probe was broken in lab just prior to post calibration 

16) Other remarks/notes: 

a) Calibration of DO for all sondes was performed on the day of deployment. 

b) Daily, Monthly, and Annual Precipitation Totals as recorded from rain gauge at 

Kingsley Plantation: 

Date Daily Precipitation Totals (inches) 

03/06/04 0.15 

03/16/04 1.62 

03/27/04 .01 
29

 Monthly total - March 1.78 

04/08/04 0.10 

04/09/04 0.14 

04/13/04 0.47 

04/14/04 0.01 

04/24/04 0.02 

 Monthly total – April 0.74 

05/01/04 0.54 

05/02/04 0.11 

05/03/04 1.13 

05/04/04 0.15 

05/16/04 0.04 

Monthly total - May 1.97 

06/02/04 0.67 

06/03/04 2.37 

06/04/04 0.74 

06/05/04 0.37 

06/06/04 0.48 

06/12/04 0.11 

06/14/04 1.61 

06/15/04 0.09 

06/20/04 0.10 

06/21/04 0.10 

06/22/04 0.46 

06/23/04 1.44 

06/24/04 0.21 

06/25/04 0.12 

06/26/04 0.94 

06/27/04 0.04 

Monthly total – June 9.85 

07/01/04 0.20 

07/02/04 0.08 

07/03/04 0.07 

07/04/04 0.97 

07/05/04 0.88 

07/07/04 0.16 

07/08/04 0.16 

07/09/04 0.44 

07/12/04 0.19 

07/13/04 0.25 

07/14/04 0.03 

07/16/04 0.70 
30

07/17/04 1.05 

07/18/04 0.09 

07/20/04 0.06 

07/31/04 0.10 

 Monthly total - July 5.43 

08/02/04 0.27 

08/03/04 0.10 

08/04/04 1.87 

08/05/04 0.15 

08/06/04 0.02 

08/14/04 2.34 

08/15/04 0.32 

08/16/04 2.39 

08/18/04 1.60 

08/19/04 0.34 

08/23/04 0.15 

08/24/04 0.18 

08/25/04 0.35 

08/30/04 0.35 

08/31/04 0.25 

 Monthly total – August 10.68 

*09/05/04 4.70 

09/14/04 2.46 

09/15/04 1.42 

09/18/04 0.34 

09/19/04 0.01 

09/21/04 0.31 

09/25/04 0.09 

09/27/04 3.69 

* Hurricane Frances - 4.70 inches was actually the total over several days between 

09/05/04 5 and 09/07/04 

 Monthly total – September 13.02 

10/02/04 0.87 

10/12/04 0.60 

10/15/04 0.71 

10/20/04 0.23 

10/22/04 0.09 

 Monthly total – October 2.50 

11/04/04 0.33 

11/26/04 0.25 

11/28/04 1.68 

 Monthly total – November 2.26 
31

12/04/04 0.06 

12/10/04 0.88 

12/11/04 0.10 

12/24/04 0.53 

12/26/04 1.23 

12/27/04 0.04 

 Monthly total – December 2.84 

01/14/05 0.59 

01/16/05 0.37 

01/23/05 0.02 

01/30/05 0.76 

 Monthly total – January 1.74 

02/02/05 0.03 

02/03/05 0.21 

02/04/05 0.16 

02/24/05 0.16 

02/25/05 0.46 

02/26/05 0.71 

02/27/05 2.43 

 Monthly total – February 4.16 

Total for sampling year March 2004 – February 2005 .............56.97 inches 

c) Wind speed and direction can have an appreciable effect on conditions at the 

Kingsley Plantation site when rainfall does not appear to be a major factor. Wind 

data reported at the Jacksonville International Airport, recorded by The Weather 

Underground, Inc. ( www.wunderground.com) was used for this report. 

d) Calculation of percentage of missing and deleted data versus total possible 

recordings for the entire sampling year revealed a 97.1% accuracy rate for the data 

sondes. (This does not include deletion of merely “suspect” data - such as isolated 

high turbidity values). 

References:

 

Adamus, C., D. Clapp, S. Brown. 1997. Surface Water Drainage Basin Boundaries: A 

Reference Guide. Technical Publication SJ97-1. Palatka, Florida: St. Johns River Water 

Management District. 

Wenner, E., D. Sanger, M. Arendt, A.F. Holland, and Y. Chen. 2004. Variability in 

Dissolved Oxygen and Other Water Quality Variables Within the National Estuarine 

Research Reserve System. Journal of Coastal Research. 45: 17-38. 

 
32

Acknowledgements:

Many thanks to the following people for their patience, dedication to detail, and hours 

spent helping to start this initial monitoring station in the program: 

- Mac Kendrick and Jim Flanagan - CAMA - installation of housing for monitoring 

equipment at Kingsley Plantation dock. 

-Pamela Chancey, Laurie Clarke, and Kelly Morgan - CAMA/ NE FL Aquatic 

Preserves- field assistance and equipment maintenance. 

-Dr. Rick Gleeson and Jon Brucker –Guana/Tolomato/Matanzas National Estuarine 

Research Reserve - data interpretation and technical assistance 

-Dr.Fred Holland and Dr. Guy DiDonato – NOAA/ Hollings Marine Laboratory – data 

interpretation and technical assistance.