2006 South Florida Environmental Report Appendix 12-4 

Appendix 12-4: Evaluation of 

Naples Bay Water Quality and 

Hydrologic Data 

Taylor Engineering, Inc., June 2005 

 App. 12-4-1 
Evaluation of Naples Bay 

Water Quality and Hydrologic Data

Final Report

June 2005
Evaluation of Naples Bay 

Water Quality and Hydrologic Data

Prepared for:

South Florida Water Management District

by:

Taylor Engineering, Inc.

9000 Cypress Green Drive

Jacksonville, FL 33256

(904)731-7040

C2004-075

June 2005
i

EXECUTIVE SUMMARY

Taylor Engineering applied the Southwest Florida Feasibility Study ACCESS database

framework to compile water quality data for Naples Bay and adjacent tributary sampling stations and 

prepare a water quality database. Upon completion of the database, Taylor Engineering evaluated the data 

for their usefulness in assessing current conditions, trends, and water quality model setup and calibration. 

Taylor Engineering also reviewed hydraulic and meteorological data for the project area to determine data 

availability for setup and calibration of a hydrodynamic model of Naples Bay.

Water quality samples from 1957 to 2003 came from 155 stations throughout the bay and

tributaries. Data that summarized water quality conditions in the bay area came from 150 of the 155 

stations representing several general locations. Lower Naples Bay included all stations south of the US 41 

bridge of the bay excluding tributaries. Upper Naples Bay included all stations above that point excluding 

tributaries. Tributary locations included (from south to north) Lely Canal, Haldeman Creek, Rock Creek, 

Gordon River, and Golden Gate Canal. The database also contains a set of stations in the Gulf of Mexico. 

The data revealed that sampling programs intermittent in period, location, and parameters

sampled. Most of the samples dated later than 1985, but the data record became more consistent in space 

and time with the advent of current ongoing sampling programs. Those efforts, started in 1999 and 2000, 

provide the most comprehensive and consistent data within the overall period of record.

Water quality data from 53 stations sampled between 1999 and 2003 provided the basis for an 

assessment of current conditions. Water quality conditions of concern in the four areas included both

chemical and biological parameters. Dissolved oxygen, nitrogen, phosphorus, copper, iron, lead, and zinc 

often exceeded state water quality standards in more than 10% of the sample sets developed from the data 

for all samples in a location. Nutrient parameters also frequently exceeded nutrient criteria defined for

Charlotte Harbor to the north and Indian River Lagoon to the east. Chlorophyll a concentrations and fecal 

coliform counts were often elevated relative to the state or regional estuary criteria. 

Examination of the entire record for water quality parameters from lower Naples Bay revealed 

that the lower bay may episodically (as recorded in the early 1990s and again in 2001) become much less 

saline than normal. The most apparent pattern in the data is a decrease in nitrogen since 1990. The data 

seem to indicate that dissolved oxygen concentrations have decreased slightly given the number of
ii

exceedances measured recently. However, this decrease may reflect the greatly increased sampling effort 

since 1999. 

Upper Naples Bay did not exhibit the same change in nitrogen concentrations as seen in the lower 

bay. Total phosphorus has decreased since 1990. As in the lower bay samples, exceedance of dissolved 

oxygen standards commonly occurred throughout the record.

The less frequently sampled tributaries provide less data for examination. Annual median

nitrogen values for Golden Gate Canal, developed from available TN and TKN data, showed a decline in 

the 1990s. That decline continued through the rest of the data record. The other tributaries did not show 

that change and generally exhibited a history of water quality problems.

Available hydraulic data provide sufficient information to develop boundary conditions for a

hydrodynamic model. Existing hydraulic information and published tide charts would allow limited

model calibration. An intensive calibration effort would require collection of tidal information at a set of 

measuring stations that would collect both hydraulic and water quality data for 48-hour periods in wet and 

dry seasons. These data collection efforts at key points within the bay would provide the necessary

information for intensive model calibration for hydraulic and water quality parameters. These efforts

would target — on a schedule from every hour to every six hours — stage, velocity, and water quality 

measurements (temperature, salinity, dissolved oxygen, turbidity, nitrogen species [TKN and

nitrite+nitrate], total phosphorus and dissolved orthophosphorus, and chlorophyll a.

The current monthly water quality sampling program conducted in most areas of the bay could 

provide most of the data necessary to verify water quality simulations. Five additional sampling sites 

would ensure complete coverage of water quality conditions and dynamics in Naples Bay south to the 

confluence of the IWW and Henderson Creek.
iii

TABLE OF CONTENTS

1.0 INTRODUCTION.....................................................................................................................1

2.0 DATA ORGANIZATION AND REVIEW..............................................................................2

2.1 Data Sources.................................................................................................................2

2.2 Database Characteristics..............................................................................................3

2.3 Sample Stations.............................................................................................................4

2.4 Data Quality..................................................................................................................5

3.0 CURRENT WATER QUALITY CONDITIONS.....................................................................9

3.1 Lower Naples Bay Current Conditions......................................................................10

3.2 Upper Naples Bay Current Water Quality Conditions.............................................12

3.3 Haldeman Creek Current Water Quality Conditions...............................................13

3.4 Gordon River Tributaries Current Water Quality Conditions.................................14

3.5 Golden Gate Canal Current Water Quality Conditions............................................15

3.6 Lely Canal Current Water Quality Conditions.........................................................16

3.7 Gulf of Mexico Current Water Quality Conditions...................................................17

3.8 Summary of Chemical Contaminant Data.................................................................18

3.9 Summary of Current Water Quality Conditions in Naples Bay ...............................19

4.0 WATER QUALITY CONDITIONS OVER TIME...............................................................20

4.1 Lower Naples Bay.......................................................................................................20

4.2 Upper Bay Trend Evaluation.....................................................................................24

4.3 Haldeman Creek.........................................................................................................27

4.4 Rock Creek.................................................................................................................29

4.5 Golden Gate Canal.....................................................................................................30

4.6 Gordon River Tributaries..........................................................................................33

4.7 Lely Canal...................................................................................................................33

5.0 HYDRAULIC – WATER QUALITY MODELING DATA GAP EVALUATION ..............36

5.1 Introduction................................................................................................................36

5.2 Data Trends and Water Quality Conditions Gap Analysis .......................................36

5.2.1 Sampling Stations Location and Periods..............................................................36

5.3 Water Circulation and Water Quality Modeling.......................................................38

5.3.1 Introduction .........................................................................................................38

5.3.2 Data for Physical Forcing in the Model ...............................................................38

5.3.3 Model Domain .....................................................................................................39
iv

5.3.4 Model Elevation Data .........................................................................................39

5.3.5 Model Input Data.................................................................................................40

5.3.6 Available Hydraulic Data....................................................................................41

5.3.7 Recommended Water Quality Data Collection.....................................................42

5.4 Summary of Recommendations.................................................................................44

REFERENCES

APPENDIX A Station Names, Locations, and Periods of Record

APPENDIX B Box and Whisker Plots of Individual Station Data Used to Evaluate Current Water 

Quality Conditions in Lower Naples Bay

APPENDIX C Box and Whisker Plots of Individual Station Data Used in to Evaluate Current Water 

Quality Conditions in Upper Naples Bay
v

LIST OF FIGURES

Figure 2.1 All Stations in the Naples Bay Database............................................................................. 6

Figure 2.2 Stations Analyzed for Water Conditions and Trends........................................................... 7

Figure 2.3 Stations with Unresolved Location (Latitude – Longitude) Data......................................... 8

Figure 3.1 Recent (1999 – 2002) Salinity Data, Lower Naples Bay ................................................... 11

Figure 4.1 Salinity Data for the Lower Bay....................................................................................... 21

Figure 4.2 All Dissolved Oxygen Values and Daily Average Values for Lower Bay Samples ........... 22

Figure 4.3 Total Nitrogen and Total Kjeldahl Nitrogen Concentrations, Lower Naples Bay............... 22

Figure 4.4 Orthophosphate Concentrations with Time, Lower Naples Bay ........................................ 23

Figure 4.5 Chlorophyll a Concentrations and Annual Median Values. Lower Naples Bay ................. 23

Figure 4.6 Average Monthly Chlorophyll a Concentration Before and After January 1, 2000, Lower 

Naples Bay ...................................................................................................................... 24

Figure 4.7 Dissolved Oxygen Concentration Data for Upper Naples Bay .......................................... 25

Figure 4.8 TN and TKN Data for Upper Naples Bay......................................................................... 25

Figure 4.9 Total Phosphorus Concentrations and Daily Median TP Values, Upper Naples Bay ......... 26

Figure 4.10 Chlorophyll a Data for Upper Naples Bay Stations........................................................... 26

Figure 4.11 Dissolved Oxygen Data for Haldeman Creek ................................................................... 27

Figure 4.12 Dissolved Oxygen with Depth Recent Samples from Haldeman Creek ............................. 28

Figure 4.13 Total Phosphorus Data from Haldeman Creek, 1990 - 2002 ............................................. 28

Figure 4.14 Fecal and Total Coliform Counts from Haldeman Creek .................................................. 29

Figure 4.15 Total Nitrogen and TKN Values and Annual Median Values for Golden Gate Canal........ 31

Figure 4.16 All TP Values and Annual Median TP Values for Golden Gate Canal Stations................. 31

Figure 4.17 Chlorophyll a Values for Golden Gate Canal Stations...................................................... 32

Figure 4.18 Dissolved Oxygen Values and Annual Median for Golden Gate Canal Stations................ 32
vi

Figure 4.19 Fecal Coliform Counts, Golden Gate Canal Stations ........................................................ 33

Figure 4.20 Dissolved Oxygen from Lely Canal Stations.................................................................... 34

Figure 4.21 Total Kjeldahl Nitrogen from Lely Canal Stations............................................................ 34

Figure 4.22 Total Phosphorus from Lely Canal Stations...................................................................... 35

Figure 5.1 Current Sampling Stations and Recommended Station Additions..................................... 37

Figure 5.2 Locations for Water Circulation and Water Quality Modeling Data Collection................. 43

LIST OF TABLES

Table 2.1 Categories of Water Quality Parameters Found in the Naples Bay Water Quality Database ... 4

Table 3.1 Numeric Water Quality Criteria, Class III Marine Waters (62-302.530 F.A.C.) ..................... 9

Table 3.2 Nutrient Criteria from Janicki (2003) Applicable to Naples Bay.......................................... 10

Table 3.3 Summary of Current Water Quality Parameters in Lower Naples Bay ................................. 11

Table 3.4 Summary of Current Water Quality Parameters in Upper Naples Bay.................................. 12

Table 3.5 Summary of Current Water Quality Parameters in Haldeman Creek .................................... 13

Table 3.6A Summary of Current Water Quality Parameters in Gordon River ........................................ 14

Table 3.6B Summary of Current Water Quality Parameters at Gordon River Downstream of Weir 951..15

Table 3.7 Summary of Current Water Quality Parameters in Golden Canal......................................... 16

Table 3.8 Summary of Current Water Quality Parameters in Lely Canal............................................. 17

Table 3.9 Summary of Current Water Quality Parameters in the Gulf of Mexico ................................ 18

Table 4.1 Summary of Selected Water Quality Data for Rock Creek................................................... 29

Table 5.1 Collier County Rainfall Data............................................................................................... 41

Table 5.2 Collier County Stage Data. Currently Active Stations are in Bold Type............................... 42

Table 5.3 Collier County Flow Data ................................................................................................... 43
1

1.0 INTRODUCTION

The South Florida Water Management District (SFWMD) contracted Taylor Engineering to

compile a database of long-term water quality data for Naples Bay. Taylor Engineering received 

instructions to “review the database for its quality, content and applicability and assess its adequacy for 

hydrodynamic and water quality model calibration and verification” (Scope of Work No. C15989-WO05-

05, Professional Science and Engineering Services). Further, “if the database is deemed inadequate for 

development of a comprehensive set of hydrodynamic and water quality models, an auxiliary data

collection program will be recommended.”

This report provides this review and recommendations for additional efforts. The report presents 

the requested analyses in the following order:

• Data organization and review

o A description of the data sources 

o A summary of the database information, including sampling site locations, plotted in

GIS, with a discussion of data location, range, and quality.

o Database statistics

• Condition / Trend Analysis 

o Evaluation of the general water quality conditions in Naples Bay in space and time. 

• Data Gap Evaluation

o An evaluation of the gaps in the hydrodynamic and water quality dataset with particular 

focus on the use of these data in the calibration and verification of a preliminary

hydrodynamic and water quality model of the bay. 

o Recommendations for data collection efforts sufficient to complete a dataset useful for 

calibration and validation of Naples Bay hydrodynamics and water quality models.
2

2.0 DATA ORGANIZATION AND REVIEW

This section provides a general description of the existing water quality data for the Naples Bay 

surface water system including data sources investigated and general descriptions of the database. 

2.1 Data Sources

Taylor Engineering contacted the following organizations identified in the Scope of Services for 

available hydrodynamic and water quality data associated with Naples Bay:

• Florida Department of Environmental Protection at the Rookery Bay National Estuarine 

Research Reserve

• City of Naples

• Collier County

• Conservancy of Southwest Florida

• South Florida Water Management District

In addition to these sources, Taylor Engineering downloaded all EPA STORET data for Collier 

County for January 1 1995 to the present; downloaded data from the FIU Southeastern Environmental

Research Center, (SERC-FIU); and reviewed USGS and NOAA online databases. SFWMD/SERC

Cooperative Agreements #C-10244 and #C-13178 as well as EPA Agreement #X994621-94-0 supported

data provided by the FIU Water Quality Monitoring Network.

Taylor Engineering compared the sample set collected from these sources with a database

recently compiled as part of the U.S. Army Corps of Engineers (USACE) Southwest Florida Feasibility 

Study (SWFFS). Reduction of the full SWFSS dataset to those data within the project watershed provided 

a basis for comparing the compiled data and the SWFFS database information. Comparison of the two 

data sets found that the SWFFS dataset contained the same water quality data Taylor Engineering

collected and provided additional metadata not readily available to Taylor Engineering. Taylor 

Engineering added data concerning sample location within the Naples Bay watershed and reviewed the 

resulting database for quality and consistency. 
3

The dataset provided a row for each parameter value for each station sampled for every sampling 

date. Each row included all associated details for the parameter. The project database product included the 

metadata for the SWFFS database, provided in separate tables.

The Taylor Engineering data analyst identified a variety of database errors and took several

actions:

• Eliminated from the database sediment data incorrectly identified as surface water data

• Eliminated unflagged, duplicate parameter data from the database when found. (Note: 

Additional like samples may remain in the database.)

• Removed stations and parameter rows without data 

• Corrected errors in latitude and or longitude data describing station locations. Note: Plotting 

all unique latitude longitude pairs revealed multiple locations with the same station code.

Comparison of other data associated with the geographic location data ruled out mislabeling 

the station code. The GIS analyst revised the incorrect data to reflect the correct location. 

Typically, either latitude or longitude was incorrect in the third or fourth decimal place. Some 

station locations remained questionable due to insufficient information or lack of a parallel 

station in the likely appropriate location.

2.2 Database Characteristics

The compiled database contains data from 155 stations sampled from 1957 to 2003. Various 

analysis in the report used data from 150 of the sampling stations (Appendix A). Data collected in 2003 

and 2004 were generally in agency review and unavailable at the time Taylor Engineering gathered the 

data. 

The 155 stations provided approximately 57,000 data from 679 separate parameters (different

parameter names), which reduced to 185 master parameters based on identified or assigned analytic

method. These 185 master parameters fit into several categories (Table 2.1). The number of master

parameters does not indicate the amount of data associated with a category. 
4

Table 2.1 Categories of Water Quality Parameters Found in the Naples Bay Water Quality Database

Parameter Type Description Master Parameters

Biological Bacterial counts, chlorophyll data, biochemical 

oxygen demand (BOD)

10

Metals 24 metals in one or more forms with concentration 

criteria for Florida surface water quality.

34

Mineral Forms of calcium, carbonate, carbon dioxide, 

chlorides, magnesium, potassium, manganese, 

total dissolved solids, salinity, sulfates

28

Nutrient Forms of nitrogen, phosphorus, and oxygen 21

Physical Turbidity, light, conductivity, acidity, alkalinity, 

temperature

10

Radiation Alpha particle measurements (very few samples) 2

Herbicides, 

Pesticides, Toxic 

Chemicals

A wide variety of pollutants with and without 

concentration criteria in Florida surface water 

quality Class III standards

76

Total 181

2.3 Sample Stations 

Most of the sampling of the 155 stations in the database occurred in the last quarter century. The 

database includes 26 stations sampled between 1957 (one station in that decade) and 1990 and 6 stations 

sampled only in the 1980s, but these 32 stations provided a minor portion of the total parameter values in 

the database. (Appendix A: Station names, periods of record, and location category). Current water 

quality evaluations used data from 53 of the 150 stations. The rest of the stations included those within 

the area of interest and without current data. Some of these samples contained data for only a single 

parameter (such as Streptococcus counts or enterobacterial counts), included only one or two sample

dates, or only a few samples providing data only on chemical contaminants. Station period data in

Appendix A may mislead the reader, as a station with a one-year period of record could have been

sampled only once or twice during that time. The remaining stations were mainly in the Gordon Canal 

system and north of the bay in the extension of the Gordon River.
5

The stations (Figure 2.1) sorted into the following locations (different zones within the project 

area):

• Lower Naples Bay (Figure 2.2: The broader bay south of the US 41 bridge crossing), 49 

stations

• Upper Naples Bay (Figure 2.2 North of the US 41 bridge to Golden Gate Canal), 12 

stations

• The tributaries (Figure 2.2 from north to south) Gordon River Extension, 6 stations

adjacent to the weir plus 21 more in the watershed; Golden Gate Canal, 7 adjacent to the 

weir and 41 in the watershed; Rock Creek, 4 stations; Haldeman Creek, 7 stations; and 

Lely Canal, 4 stations. 

• Gulf of Mexico (Figure 2.2) 5 stations.

2.4 Data Quality

The data range widely in quality. More than half the parameter values have no STORET code or 

Standard Method number. Approximately half the data have no depth information. Thus, most analyses 

required some assumptions about the data. In the absence of depth information, Taylor Engineering

assumed a surface sample. A fraction of the data includes flags for a variety of reasons, most notably

unverifiable data, and unknown duplicate status of data. Station latitude and longitude data do not always 

correspond to the station name and description, problems corrected when a clear reason (identical station 

description for a different station name or station identification code) existed. However, stations with 

questionable location information remain in the database when resolving the issue became impossible 

(Figure 2.3). Database users should review station locations and descriptions before they access the data.
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MILLER CANAL

TAMIAMI CANAL

I-75 CANAL

GOLDEN GATE MAIN CANAL

COCOHATCHEE CANAL

CR-951 CANAL

CYPRESS CANAL

AIRPORT ROAD CANAL

HENDERSON CREEK CANAL

LELY CANAL

GREEN CANAL

CORKSCREW CANAL

GOLDEN GATE CANAL

CURRY CANAL

ORANGE TREE CANAL

HALDEMAN CREEK

C-1 CONNECTOR CANAL

GORDON RIVER

I-75 CANAL

COCOHATCHEE RIVER

NORTH NAPLE DRAINAGE CANA

Figure 2.1 All Stations in the Naples Bay Database

LEGEND

River

Creek

Primary Canal

Tertiary Canal

LOCATION

! Gordon River

! Golden Gate Canal

! Haldeman Creek

! Rock Creek

! Lely Canal

! Upper Bay

! Lower Bay

! Upper Tributary

! Gulf

! Tributaries

0 1 2

Miles

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LELY CANAL

GOLDEN GATE MAIN CANAL

HALDEMAN CREEK

GORDON

RIVER

A RI PORT ROAD CANAL

Figure 2.2 Stations Analyzed for Water Conditions and Trends

LEGEND

Canals

River

Creek

Primary Canal

Tertiary Canal

^ Stations - Taylor Analysis

0 0.5 1

Miles

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LELY CANAL

HALDEMAN CREEK

GORDON RIVER

GOLDEN GATE MA NI CANAL

Figure 2.3 Stations with Unresolved Location (Latitude - Longitude) Data

LEGEND

Canals

River

Creek

Primary Canal

Tertiary Canal

D Stations - Lat/Long Error

0 1 2

Miles

·

(X) Number of Stations at Location

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(3)

(3)

(3)

(2)

(2)
9

3.0 CURRENT WATER QUALITY CONDITIONS 

The summaries of current water quality conditions in Naples Bay for the Lower Bay, Upper Bay, 

Golden Gate Canal, Haldeman Creek, and Lely Canal considered the available data from 1999 – 2003. 

Lely Creek samples from a single station provided the current data for that tributary. Resumed only 

recently, sampling at Rock Creek produced insufficient data to construct a meaningful summary.

Florida numeric water quality standards (Table 3.1) provided the primary means of assessing

water quality. Nutrient criteria identified in Janicki (2003) from the Charlotte Harbor Estuary Program 

(CHNEP) and the Indian River Lagoon SWIM Restoration Program (Table 3.2) provided insight into 

current conditions. Percent exceedances of numeric criteria provided a measure of impaired water status 

for the four areas. For fecal coliform counts, the value of 400 counts/100 ml provided the monthly

exceedance measure. Insufficient numbers of multiple samples within a month at any station precluded an 

evaluation of monthly averages over the period of evaluation.

Table 3.1 Numeric Water Quality Criteria, Class III Marine Waters (62-302.530 F.A.C.)

Parameter Class III Predominantly Marine Waters

Aluminum (mg/L) = 1.5

Arsenic (μg/L) = 50

Fecal Coliforms (#/100 ml) = 400 monthly, 800 maximum

Total Coliforms (#/100 ml) = 1000 monthly, 2400 maximum

Cadmium (μg/L) = 9.3

Chromium (hexavalent) = 50

Copper (μg/L) = 50

Dissolved Oxygen (mg/L) = 4.0 (marine waters)

= 5.0 (freshwater)

Iron (mg/L) = 0.3

Lead (μg/L) = 8.5

Phosphorus (mg/L) = 0.1 

Turbidity (NTU) =29 above natural background

Zinc (μg/L) = 86

Freshwater dissolved oxygen criterion (D.O. = 5.0 mg/L) applied to tributary sampling station

data upstream of weirs.
10

Table 3.2 Nutrient Criteria from Janicki (2003) applicable to Naples Bay

CRITERIA

Source

TP 

(mg/L)

TN 

(mg/L) Chlor a (ug/L) Secchi Disk 

depth (m)

Turbidity 

(NTU)

CHNEP* 0.01 0.40 2.1 0.70 2.2

IRL** 0.053 0.692 3.1 1.44 2.84

*Data for 25th percentile of the data for a parameter

**Not-to-exceed value

Appendix B provides box and whisker plots of key water quality variables from individual lower 

bay stations for the current conditions period (1999 – 2002). 

3.1 Lower Naples Bay Current Conditions

The southern, wider portion of Naples Bay showed elevated levels of many parameters and

exceedances of water quality standards for several metals and fecal coliform maximum values. While 

typically near marine salinity conditions, the bay may experience very low salinity conditions during the 

summer rainy season. (Table 3.3: Salinity minimum value) The most recent low salinity event recorded in 

the database occurred in summer 2001 (Figure 3.1). Turbidity was typically low, and median secchi disk 

depth was 1.2 m. The lower bay data exceeded acceptable CHNEP water quality parameters for TP,

chlorophyll a, and turbidity. A large fraction or a majority of the copper, iron, lead, and zinc samples 

exceeded water quality standards (Table 3.3). Lower Bay sample nutrient values at the 75th percentile and 

above exceeded all IRL nutrient criteria.
11

Table 3.3 Summary of Current Water Quality Parameters in Lower Naples Bay

Lower Naples Bay

Parameter N Min 25th % Mean Median 75th % Max % Exc

Salinity (%o) 277 0.48 30.20 31.34 34.10 35.60 41.50 N/A

Temperature (oC) 267 5.30 22.30 25.45 26.20 29.30 32.40 N/A

Turbidity (NTU) 166 0.30 2.30 4.60 3.20 5.00 30.40 N/A

Secchi (m) 108 0.40 0.90 1.92 1.20 2.54 8.86 N/A

DO (mg/l) 267 1.50 4.50 5.75 5.60 6.70 19.40 16.1

TP (mg/l) 151 0.0018 0.0313 0.0445 0.0389 0.0525 0.1100 2.0

SRP (mg/l) 124 0.0003 0.0031 0.0088 0.0061 0.0111 0.0530 N/A

TN (mg/l) 124 0.022 0.190 0.339 0.295 0.415 1.550 N/A

NH4 (mg/l) 120 0.00 0.01 0.08 0.01 0.03 5.01 N/A

Chlor A (mg/l) 201 0.15 2.70 6.34 4.80 8.00 87.00 N/A

Fecal (CFU/100 ml) 103 1 3 147 27 130 3200 3.9

TSS (mg/l) 39 1.00 6.00 15.72 8.40 18.20 76.00 N/A

Arsenic (μg/l) 40 0.50 4.30 4.05 5.00 5.00 5.00 0

Cadmium (μg/l) 42 0.05 0.33 2.73 2.50 2.50 12.00 4.8

Chromium (μg/l) 42 1.0 1.0 4.4 2.5 6.0 22.0 0

Copper (μg/l) 42 0.5 2.2 5.9 5.0 5.0 47.0 66.7

Iron (mg/l) 10 0.3 0.4 0.7 0.5 0.5 2.5 90.0

Lead (μg/l) 42 0.5 1.4 6.9 2.5 13.0 26.0 35.7

Zinc (μg/l) 42 5.0 5.0 15.5 5.0 10.0 60.0 28.6

Current Salinity Record Lower Naples Bay

0

5

10

15

20

25

30

35

40

45

Jul-98 Feb-99 Aug-99 Mar-00 Oct-00 Apr-01 Nov-01 May-02 Dec-02 Jun-03

Date

Salinity (ppt)

Figure 3.1 Recent (1999 – 2002) Salinity Data, Lower Naples Bay
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3.2 Upper Naples Bay Current Water Quality Conditions

Fewer data for current conditions in upper Naples Bay (Table 3.4) reflected sampling of fewer 

stations over the period and shorter periods of record at individual stations. Relative to the lower bay, the 

upper bay is less saline, and has slightly lower water clarity (as indicated by secchi disk depth). However, 

the upper bay also showed slightly lower average turbidity. TP and chlorophyll a levels are higher and 

18% of TP samples exceeded 0.1 mg/L. Fecal coliform counts also exceeded standards more frequently in 

the upper bay. Dissolved oxygen exceedances were infrequent, but present. Metal concentrations and

exceedances in the upper bay were similar in frequency to those in the lower bay. Again, water quality 

conditions exceed CHNEP and IRL standards, and metal exceedances suggest that a bay area impaired 

with respect to copper, iron, and lead.

Table 3.4 Summary of Current Water Quality Parameters in Upper Naples Bay

Upper Naples bay

Parameter N Min 25th % Mean Median 75th % Max % Exc

Salinity (%o) 27 0.48 10.54 21.51 27.59 30.65 34.85 N/A

Temperature (oC) 27 19.80 24.60 26.58 26.80 29.00 32.30 N/A

Turbidity (NTU) 39 1.60 2.20 3.20 2.67 3.37 9.80 N/A

Secchi (m) 27 0.45 0.85 0.99 1.00 1.10 1.50 N/A

DO (mg/l) 27 3.04 4.26 5.50 5.64 6.22 8.55 11.1

TP (mg/l) 22 0.04 0.04 0.07 0.05 0.09 0.20 18.2

SRP (mg/l) 27 0.01 0.02 0.08 0.04 0.17 0.22 N/A

TN (mg/l) 26 0.14 0.49 0.68 0.63 0.87 1.52 N/A

NH4 (mg/l) 15 0.03 0.05 0.10 0.09 0.11 0.20 N/A

Chlor A (mg/l) 39 1.50 3.20 8.20 5.30 11.70 25.10 N/A

Fecal (CFU/100 ml) 39 3 60 269 142 220 3200 7.7

TSS (mg/l) 23 0.80 1.60 6.49 4.00 12.20 16.20 N/A

Arsenic (μg/l) 23 0.50 5.00 4.17 5.00 5.00 5.00 0

Cadmium (μg/l) 24 0.05 1.50 2.84 2.50 2.50 14.00 8.3

Chromium (μg/l) 24 1.00 1.75 4.04 2.50 3.75 13.00 0

Copper (μg/l) 24 0.50 2.55 4.03 5.00 5.00 8.00 62.5

Iron (mg/l) 5 0.29 0.32 0.83 0.46 0.53 2.53 80.0

Lead (μg/l) 24 0.50 1.75 4.98 2.50 6.00 24.00 16.7

Zinc (μg/l) 24 5 5 16 5 15 60 0.0

Appendix C provides box and whisker plots for salinity, turbidity, nutrients, and fecal coliform 

data from upper Naples Bay stations.
13

3.3 Haldeman Creek Current Water Quality Conditions 

Haldeman Creek is tidal in the reaches sampled. Salinity levels during winter periods approached 

marine conditions. The water contained relatively low nutrient (TP, TN, NH4) concentrations, but also 

showed dissolved oxygen exceedances sufficient to suggest impairment for this parameter. Chlorophyll a 

statistics were similar to those in upper Naples Bay and were higher than in lower Naples Bay, the 

receiving waters of Haldeman Creek. Maximum fecal coliform counts exceeded state standards. Copper 

and iron concentrations most often exceeded water quality standards suggesting impairment of Haldeman 

Creek with respect to those two parameters.

Table 3.5 Summary of Current Water Quality Parameters in Haldeman Creek

Haldeman Creek

Parameter N Min 25th % Mean Median 75th % Max % Exc

Salinity (%o) 40 0.27 20.30 24.41 30.03 32.59 36.40 N/A

Temperature (oC) 40 18.80 24.45 26.23 27.00 29.10 32.30 N/A

Turbidity (NTU) 34 0.90 1.60 2.73 2.41 3.55 5.99 N/A

Secchi (m) 40 0.60 0.95 1.09 1.18 1.20 1.40 N/A

DO (mg/l) 40 2.45 3.67 4.41 4.21 5.18 7.84 45

TP (mg/l) 16 0.01 0.03 0.04 0.04 0.04 0.07 0

SRP (mg/l) 24 0.01 0.01 0.03 0.01 0.04 0.10 N/A

TN (mg/l) 20 0.14 0.31 0.59 0.71 0.81 1.05 N/A

NH4 (mg/l) 10 0.02 0.02 0.09 0.08 0.16 0.19 N/A

Chlor A (mg/l) 34 1.50 4.80 8.21 7.89 11.00 21.90 N/A

Fecal (CFU/100 ml) 34 2 50 330 330 420 1540 5.9

TSS (mg/l) 12 1.80 4.60 8.80 8.10 13.15 17.80 N/A

Arsenic (μg/l) 18 0.5 3.4 4.0 5.0 5.0 5.0 0

Cadmium (μg/l) 19 0.1 0.1 1.9 2.5 2.5 6.0 0

Chromium (μg/l) 19 1.0 1.0 3.4 2.5 2.5 10.0 0

Copper (μg/l) 19 0.5 5.0 13.6 5.0 8.4 150.0 78.9

Iron (mg/l) 6 0.2 0.3 0.4 0.3 0.4 0.7 83.3

Lead (μg/l) N/A

Zinc (μg/l) 19 5.00 5.00 17.37 5.00 30.00 60.00 0
14

3.4 Gordon River Tributaries Current Water Quality Conditions 

Water quality in the Gordon River above the weir showed low concentrations of dissolved

oxygen. All of the samples exceeded (were lower than) the 5 mg D.O. /L state freshwater quality standard

(Table 3.6 A). Secchi disk depth ranged from 0.5 m to 1.5 m, averaging about 1.1 meter. All other 

parameters remained within the state water quality standards.

Table 3.6 A Summary of Current Water Quality Parameters Gordon River above Weir 951

Gordon River Above Weir 951

Parameter N Min 25th % Mean Median 75th % Max % Exc

Salinity (%o)

Temperature (oC) 6 26.27 27.18 27.50 27.35 27.99 28.85 N/A

Turbidity (NTU)

Secchi (m) 5 0.50 1.10 1.16 1.30 1.40 1.50 N/A

DO (mg/l) 6 1.35 2.66 3.04 2.92 3.46 4.95 100

TP (mg/l) 7 0.02 0.03 0.05 0.05 0.06 0.08 0

SRP (mg/l) 6 0.03 0.08 0.09 0.09 0.11 0.15 N/A

TN (mg/l) 7 0.96 1.12 1.47 1.26 1.47 2.88 N/A

NH4 (mg/l) 6 0.03 0.04 0.06 0.05 0.08 0.12 N/A

Chlor A (mg/l) 4 0.85 0.85 14.43 13.43 28.00 30.00 N/A

Fecal (CFU/100 ml)

TSS (mg/l)

Arsenic (μg/l) 4 7.00 7.00 8.45 7.40 9.90 12.00 0

Cadmium (μg/l)

Chromium (μg/l) 12 1.00 1.00 3.30 2.00 6.40 7.40 N/D*

Copper (μg/l) 6 2.80 5.90 8.78 7.50 13.00 16 N/D*

Iron (mg/l)

Lead (μg/l) 6 0.25 5.00 7.04 7.50 10.00 12.00 N/D*

Zinc (μg/l) 6 1.00 1.00 5.58 4.65 6.80 15.40 N/D*

* N/D No Alkalinity Data Available to Calculate Exceedances

Water quality in the Gordon River location downstream of the weir (Table 3.6 B) was similar in 

several respects to the upper bay quality. The salinity ranged from less than 1 to 36 ppt. Turbidity was 

typically low, with a maximum of 6 NTU. Secchi disk depth ranged from 0.55 m to 1.6 m, averaging 

about 1.1 meter. Almost 89% of the dissolved oxygen data exceeded (lower than) the 4 mg D.O. /L Class

III marine water standard. Total phosphorus exceeded 0.1 mg/L in half the samples. As at other locations 
15

in Naples Bay, copper and iron concentrations exceeded standards sufficiently to consider the area under 

impaired waters criteria.

Table 3.6 B Summary of Current Water Quality Parameters at Gordon River Downstream of Weir 951

Gordon River Downstream Weir 951

Parameter N Min 25th % Mean Median 75th % Max % Exc

Salinity (%o) 35 0.42 1.45 13.40 15.11 22.91 30.60 N/A

Temperature (oC) 35 19.70 23.60 25.85 26.40 27.90 31.70 N/A

Turbidity (NTU) 21 0.80 1.20 1.74 1.50 1.90 4.50 N/A

Secchi (m) 35 0.55 1.00 1.12 1.10 1.25 1.60 N/A

DO (mg/l) 35 0.92 1.72 3.13 2.41 3.26 16.10 88.6

TP (mg/l) 4 0.07 0.07 0.10 0.10 0.13 0.14 50.0

SRP (mg/l) 5 0.04 0.05 0.07 0.08 0.08 0.08 N/A

TN (mg/l) 8 0.65 0.76 0.90 0.88 1.08 1.15 N/A

NH4 (mg/l) 2 0.13 0.13 0.15 0.15 0.16 0.16 N/A

Chlor A (mg/l) 21 1.50 1.50 8.36 5.90 8.50 27.80 N/A

Fecal (CFU/100 ml) 21 19 71 186 116 180 840 4.8

TSS (mg/l) 5 1.00 1.00 1.20 1.00 1.00 2.00 N/A

Arsenic (μg/l) 5 0.50 0.50 2.31 2.40 3.67 4.50 0

Cadmium (μg/l) 6 0.05 0.05 0.07 0.05 0.10 0.10 0

Chromium (μg/l) 6 1.00 1.00 1.00 1.00 1.00 1.00 0

Copper (μg/l) 6 0.50 0.50 1.72 1.50 2.20 4 16.7

Iron (mg/l) 5 0.06 0.20 0.22 0.23 0.26 0.36 20.0

Lead (μg/l) 6 0.50 0.50 0.50 0.50 0.50 0.50 0

Zinc (μg/l) 6 10.00 10.00 26.67 30.00 40.00 40.00 0

3.5 Golden Gate Canal Current Water Quality Conditions

Water quality conditions in Golden Gate Canal (Table 3.7) varied more than in the upper bay, the 

canal’s receiving water. Sampling locations included both tailwater and headwater, which influenced the 

range of salinity, which was very low west of the weir where much of the sampling occurred. Turbidity,

although usually low, included a few values several times greater than the typical condition. Water clarity 

(secchi disk depth) was similar to that in the upper bay locations. Dissolved oxygen levels were indicative 

of impaired water conditions. Elevated total phosphorus concentrations, typically above 0.1 mg/L, might 

likely have a negative effect on downstream water quality. Total nitrogen and ammonium ion remained 

within relatively narrow ranges of concentration, but TN concentrations were higher than CHNEP and 
16

IRL acceptable levels. As with most other locations in the bay, more than 10% of the copper and iron 

concentration data exceeded state water quality criteria for Class III marine waters. 

Table 3.7 Summary of Current Water Quality Parameters in Golden Gate Canal Downstream from 

the Golden Gate Weir

Golden Gate Canal

Parameter N Min 25th % Mean Median 75th % Max % Exc

Salinity (%o) 88 0.00 0.34 7.74 0.37 19.06 31.97 N/A

Temperature (oC) 151 18.10 23.10 25.24 25.00 23.10 33.10 N/A

Turbidity (NTU) 92 0.70 1.50 2.42 2.10 2.90 14.20 N/A

Secchi (m) 134 0.15 1.30 1.55 1.55 1.75 6.00 N/A

DO (mg/l) 151 0.60 4.61 5.48 5.46 6.60 14.00 17.9

TP (mg/l) 57 0.01 0.02 0.03 0.03 0.04 0.10 0

SRP (mg/l) 46 0.002 0.006 0.012 0.010 0.02 0.04 N/A

TN (mg/l) 66 0.12 0.66 0.75 0.74 0.84 1.14 N/A

NH4 (mg/l) 57 0.01 0.03 0.05 0.04 0.07 0.21 N/A

Chlor A (mg/l) 54 1.10 1.50 5.25 3.20 5.90 48.60 N/A

Fecal (CFU/100 ml) 92 2 16 85 31 69 1900 2.2

TSS (mg/l) 66 1.00 4.00 4.56 4.00 4.00 24.00 N/A

Arsenic (μg/l) 11 0.50 0.50 1.99 1.50 3.80 4.28 0

Cadmium (μg/l) 12 0.05 0.05 0.10 0.08 0.10 0.27 0

Chromium (μg/l) 12 1.00 1.00 1.00 1.00 1.00 1.00 0

Copper (μg/l) 12 0.50 0.50 0.80 0.50 0.80 2.20 0

Iron (mg/l) 18 0.25 0.50 2.78 0.50 5.00 12.00 44.4

Lead (μg/l) 12 0.50 0.50 0.66 0.50 0.50 2.37 0

Zinc (μg/l) 12 10.00 10.00 17.50 20.00 20.00 30.00 0

3.6 Lely Canal Current Water Quality Conditions

Water quality conditions in Lely Canal varied by sample station location (Table 3.8). Sampling 

locations for current conditions included one station at the northern section of the canal. This fact explains 

the low salinity values measured — between 0.09%o and 14.74 %o. Water clarity (secchi disk depth) was 

lower that the lower bay locations. Dissolved oxygen levels were indicative of impaired water conditions

— 54 % of the measurements were below 5 mg/l. Elevated total phosphorus concentrations, typically 

above 0.1 mg/L, could have a negative effect on downstream water quality. Metal concentrations never 

exceeded state water quality criteria for Class III fresh waters. 
17

Table 3.8 Summary of Current Water Quality Parameters in Lely Canal

Lely Canal

Parameter N Min 25th % Mean Median 75th % Max % Exc

Salinity (%o) 39 0.09 0.32 0.98 0.36 0.38 14.74 N/A

Temperature (oC) 39 18.10 23.40 26.02 26.50 29.10 32.00 N/A

Turbidity (NTU) 41 0.60 1.30 2.09 1.80 2.40 7.50 N/A

Secchi (m) 35 0.30 0.70 0.97 0.90 1.20 1.60 N/A

DO (mg/l) 31 2.44 3.83 5.00 4.92 5.95 8.83 54.8

TP (mg/l) 25 0.01 0.02 0.04 0.03 0.03 0.17 4.0

SRP (mg/l) 12 0.005 0.005 0.013 0.007 0.01 0.07 N/A

TN (mg/l) 25 0.02 0.55 0.61 0.70 0.80 1.02 N/A

NH4 (mg/l) 22 0.01 0.03 0.06 0.04 0.07 0.21 N/A

Chlor A (mg/l) 24 3.20 3.70 7.67 4.80 10.40 20.30 N/A

Fecal (CFU/100 ml) 26 23 62 142 94 143 700 0

TSS (mg/l) 7 2.00 2.00 4.14 4.00 6.00 9.00 N/A

Arsenic (μg/l) 8 1.70 1.87 2.63 2.49 3.31 4.00 0

Cadmium (μg/l)

Chromium (μg/l) 1 1.10 1.10 1.10 1.10 1.10 1.10 0

Copper (μg/l) 7 1.90 2.00 2.94 3.20 3.60 4.10 0

Iron (mg/l) 12 0.19 0.27 0.41 0.36 0.54 0.77 0

Lead (μg/l) 1 0.54 0.54 0.54 0.54 0.54 0.54 0

Zinc (μg/l) 2 10.00 10.00 14.00 14.00 18.00 18.00 0

3.7 Gulf of Mexico Current Water Quality Conditions 

Current samples from Gulf of Mexico came primarily from a station directly adjacent to Gordon 

Pass. The data (Table 3.9) showed the effect of Naples Bay water on water quality at the station. Salinity, 

typically marine (35 ppt) fell as low as 29 ppt during the three-year period of evaluation. Elevated 

maximum values of nutrients, chlorophyll a, and fecal coliform counts reflected the occasional impact of 

the bay on the nearshore Gulf Waters. Lead concentrations, measured nine times, exceeded the state water 

quality standard in six of the nine samples. 
18

Table 3.9 Summary of Current Water Quality Parameters in the Gulf of Mexico

Gulf of Mexico

Parameter N Min 25th % Mean Median 75th % Max % Exc

Salinity (%o) 102 29.20 34.30 35.14 35.20 36.30 37.90 N/A

Temperature (oC) 94 7.50 21.40 25.03 25.60 29.40 31.50 N/A

Turbidity (NTU) 55 0.30 1.10 3.51 2.00 3.30 25.10 N/A

Secchi (m) N/A

DO (mg/l) 94 2.10 5.50 6.36 6.20 6.90 16.80 2.1

TP (mg/l) 50 0.01 0.02 0.03 0.03 0.04 0.09 0

SRP (mg/l) 62 0.00 0.00 0.01 0.01 0.01 0.04 N/A

TN (mg/l) 32 0.05 0.15 0.21 0.18 0.27 0.51 N/A

NH4 (mg/l) 54 0.00 0.00 0.02 0.01 0.02 0.20 N/A

Chlor A (mg/l) 58 0.40 1.30 2.98 2.50 3.60 11.90 N/A

Fecal (CFU/100 ml) 254 1 2 23 4 12 1500 0.8

TSS (mg/l) 9 5.20 5.60 18.61 5.70 43.00 46.20 N/A

Arsenic (μg/l) 9 5 5 5 5 5 5 0

Cadmium (μg/l) 9 2.5 2.5 2.5 2.5 2.5 2.5 0

Chromium (μg/l) 9 2.5 2.5 7.0 2.5 13 19.0 0

Copper (μg/l) 9 0.5 5 4.6 5 5 10.0 0

Iron (mg/l)

Lead (μg/l) 9 3 8 15.7 18 23 34 66.7

Zinc (μg/l) 9 5 5 5 5 5 5 0

3.8 Summary of Chemical Contaminant Data 

Data for a large number of chemical contaminants reside in the database. Collection of the 

majority of the chemical contaminant (industrial chemicals, herbicides, and pesticides) data occurred in 

the 1970s. Data from a 1996 and 1997 City of Naples effort to measure chemical contaminants in the 

waters of the bay and tributaries sampling reside in the database. The results of this sampling effort and 

those of more recent sampling did not usually exceed detection limits and did not show chemical

contamination as a major concern where tested. In 2002, sampling of Townsend Canal near the Berry 

Grove Pump Station found a variety of chemical contaminants. Few of the detected compounds have 

numeric water quality standard concentrations, but many have recognized toxicity, a concern if found in 

the potable water pumped by the Berry Grove Station. 
19

3.9 Summary of Current Water Quality Conditions in Naples Bay

Water quality data from Naples Bay and its tributaries showed several signs of water quality

impairment. Dissolved oxygen reached levels of concern in all areas of the bay. One or more of the metals

— copper, iron, zinc, and lead concentrations — exceeded water quality standards in the several locations 

evaluated within the bay and in the Gulf of Mexico. Slightly elevated phosphorus levels in lower Naples 

Bay increased in upper Naples Bay and in Golden Gate Canal, the main freshwater discharge to the bay. 

Greater than 10% of the total samples collected in each location except the Gulf of Mexico exceeded state 

dissolved oxygen standards. Nitrogen levels in the lower bay were close to CHNEP and IRL water quality 

criteria, but the upper bay concentrations were higher and clearly exceeded those standards. Chlorophyll a 

values in all locations typically (as mean or median value) exceeded criteria developed for Charlotte 

Harbor and the Indian River Lagoon. 
20

4.0 WATER QUALITY CONDITIONS OVER TIME

Water quality data were minimally sufficient to provide a picture of current and past water quality 

conditions. While the database contained a large number of sites (Figure 1.1), the relatively incomplete 

distribution of the sampling stations in space and time and the inconsistent collection of key parameter 

data limited the strength of conclusions drawn from the dataset. A few single sampling stations generated 

data sufficient to develop a trend analysis as long as five years. Therefore, Taylor Engineering

approached analysis of potential trends by plotting daily and median values of all available data for 

comparison. Collection of multiple samples of some parameters such as dissolved oxygen often occurred 

on the same day. Daily averages of those values plotted with the raw data provided a better understanding 

of the typical condition at those sites.

The water quality period for any particular parameter with relatively large numbers of data

typically extended back no further than the late 1980s. The historic analysis includes samples from the 

1970s. Visual examination of superimposed individual and annual median parameter values provided

heuristic trend assessment. The trend assessment focuses on traditional water quality parameters: salinity, 

turbidity, dissolved oxygen, total nutrients, chlorophyll a, and coliform counts. However, the discussions 

of water quality trend in each location include only present parameter data of particular interest. Not all 

parameters provided key information in any particular location.

4.1 Lower Naples Bay 

Trends in water quality became most apparent in lower Naples Bay. Salinity data suggested that 

episodes of low salinity have occurred in the lower bay since the late 1980s (Compare Figure 4.1, 

available historic salinity data, to Figure 3.1, recent salinity data from the lower bay). Turbidity, while 

occasionally very high, remained relatively consistent for the period of record. Multiple dissolved oxygen 

measurements occurred within a 24-hour period. Figure 4.2 provides all values and daily average values. 

D.O. values below 4.0 mg/L increased in recent years, but little difference occurred in daily average 

values in the data from 1988 to 1994 (Figure 4.2). 

Total nitrogen (TN or TKN) concentrations (Figure 4.3) decreased significantly (statistically 

significant trend line slope) over the period of record (1988 – 2002). Changes in total phosphorus levels 

did not accompany changes in TN. Orthophosphate concentrations in the 1970s (Figure 4.4) may have 

been higher than current levels, but insufficient data exist between that time and the present to assess 

change. Chlorophyll a concentrations varied in the same range throughout the data record. Annual median 
21

concentrations of the past five years suggest lower chlorophyll a levels, but only sampling since 2000 

included all months of each year. Monthly average chlorophyll a concentrations for the periods before and 

since January 1, 2000 (Figure 4.5) suggest that recent chlorophyll a levels were less variable and lower

than in the previous period (Figure 4.6: average month = 6 mg/m3 after 2000 and 8 mg/m3 before that 

time). However, regular monthly sampling in recent years has produced as many samples as in the rest of 

the remaining data record. In the data set for the period before 2000, data from two months (April and 

August) comprised 45% of the data. Data from additional years will determine whether the current data 

reflect a long-term trend or a short-term condition.

The database provided fecal and total coliforms data dating to 1971. The few data available 

comprised values that were generally close to current sample values. Recent (1999 — 2002) samples 

however, included higher total coliform counts than previously recorded.

Historic Salinity Data

0

5

10

15

20

25

30

35

40

45

Aug-87 Dec-88 May-90 Sep-91 Jan-93 Jun-94 Oct-95 Mar-97

Date

Salinity (ppt)

Figure 4.1 Salinity Data for the Lower Bay 1988 – 1997.
22

 D.O. Values - Lower Bay

0

5

10

15

20

Jan-78 Oct-80 Jul-83 Mar-86 Dec-88 Sep-91 Jun-94 Mar-97 Dec-99 Sep-02

Date

mg D.O. / L

D.O. Values

Average Daily D.O.

Figure 4.2 All Dissolved Oxygen Values and Daily Average Values for Lower Bay Samples

TN Lower Bay

0

0.5

1

1.5

2

2.5

Aug-87 May-90 Jan-93 Oct-95 Jul-98 Apr-01 Jan-04

Date

mg TN or TKN / L

TN or TKN Values

Annual Median

Figure 4.3 Total Nitrogen and Total Kjeldahl Nitrogen Concentrations, Lower Naples Bay. 
23

Orthophosphate, Lower Bay

0

0.05

0.1

0.15

0.2

0.25

Mar-71 Aug-76 Feb-82 Aug-87 Jan-93 Jul-98 Jan-04

Date

mg PO4 as P / L

Figure 4.4 Orthophosphate Concentrations with Time, Lower Naples Bay

Chlorophyll a Lower Bay

0

25

50

75

100

Aug-87 May-90 Jan-93 Oct-95 Jul-98 Apr-01 Jan-04

Date

mg Chlor a / m3

Chlor a Values

Annual

Median

Figure 4.5 .Chlorophyll a Concentration Data and Annual Median Values, Lower Naples Bay
24

Average Monthly Chlorophyll a

0

5

10

15

20

25

Jan

FebMar

Apr

May

Jun

Jul

AugSep

Oct

NovDec

Month

mg Chlor a / m3

2000+

Before 2000

Figure 4.6 Average Monthly Chlorophyll a Concentrations before and after January 1 2000, Lower 

Naples Bay

4.2 Upper Bay Trend Evaluation

Upper bay data occurred in three clusters: a small dataset from the early 1970s, a second, larger 

set of samples collected between 1988 and 1994, and data from 1997 to the present. Regular monthly 

sampling did not begin until the fall of 2000. The salinity data between 1988 and 1994 showed the same 

range as the current (1999 – 2002) dataset. No patterns appeared in salinity, turbidity, or coliform

datasets. Dissolved oxygen concentrations lower than 4.0 mg/L (Figure 4.7) did not decrease greatly 

between the early 1990s and the current period, although both periods had lower percent exceedances 

than data from the beginning of the record (Figure 4.7).

Nitrogen data consisted primarily of sets of multiple samples within a 24-hour period, separated 

by months or years. Combining TN and TKN data provided the largest set of data for review. The

available data, plotted with daily average values (Figure 4.8), suggest no pattern of change in

concentrations over time. 

The phosphorus data collected since early 1992 show a smaller range of values than the previous 

period of data (Figure 4.9). The data may represent a long-term improvement in water quality for this 
25

parameter, but phosphorus in the upper bay has yet to meet the state water quality criterion for

phosphorus. Chlorophyll a concentration data showed no clear pattern of change (figure 4.10).

Dissolved Oxygen Upper Bay

0

1

2

3

4

5

6

7

8

9

Mar-71 Aug-76 Feb-82 Aug-87 Jan-93 Jul-98 Jan-04

Date

mg D.O. / L

Figure 4.7 Dissolved Oxygen Concentration Data for Upper Naples Bay

TN or TKN, Upper Bay

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

08/11/87 05/07/90 01/31/93 10/28/95 07/24/98 04/19/01 01/14/04

Date

mg TN or TKN / L

All Values

Daily Average

Values

Figure 4.8 TN and TKN Data for Upper Naples Bay
26

Total Phosphorus Upper Bay

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

Mar-71 Aug-76 Feb-82 Aug-87 Jan-93 Jul-98 Jan-04

Date

mg TP / L

All Values

Daily AVerage Values

Figure 4.9 Phosphorus Concentration Data and Daily Average Values

Chlorophyll a Upper Bay

0.00

5.00

10.00

15.00

20.00

25.00

30.00

35.00

40.00

8/11/1987 5/7/1990 1/31/1993 10/28/1995 7/24/1998 4/19/2001 1/14/2004

Date

mg Chlorophyll a / m3

All Values

Average Daily Values

Figure 4.10 Chlorophyll a Data for Upper Naples Bay
27

4.3 Haldeman Creek

Haldeman Creek sampling has occurred several times each year since 1989. The current sampling 

effort on the creek began in 1999. Sampling, historically intermittent, now occurs monthly. 

Historically, salinity values have ranged from less than 1 to over 30 ppt. Turbidity, typically less 

than 10 units, has risen as high as 60 NTU. Dissolved oxygen has often fallen below 4 mg /L through the 

period of record (Figure 4.11). Depth of measurement varied, but did not show a strong influence on the 

measured dissolved oxygen level (Figure 4.12). Annual median data suggest a recent decline in typical 

dissolved oxygen concentrations compared to the first half of the 1990s. 

TN values varied little over the 12-year period of record, and no trend appeared in the data. Total 

phosphorus concentrations may have fallen since the early 1990s and, with few exceptions,

concentrations have remained below 100 μg/L (Figure 4.13).

Fecal coliform counts since 1989 exceeded 400 counts/100 ml in 18% of the samples. similar 

exceedances occurred across the period of record, (Figure 4.14). 

Dissolved Oxygen Haldeman Creek

0

2

4

6

8

10

12

Aug-72 Feb-78 Aug-83 Feb-89 Jul-94 Jan-00 Jul-05

Date

mg D.O. / L

D.O. Values

Annual Median

Figure 4.11 Dissolved Oxygen data for Haldeman Creek
28

 D.O. with Depth Haldeman Creek (2000 - 2002)

0

1

2

3

4

5

6

7

8

9

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8

Depth (m)

mg D.O. / L

Figure 4.12 Dissolved Oxygen with Depth, from Haldeman Creek

TP Haldeman Creek

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

May-90 Sep-91 Jan-93 Jun-94 Oct-95 Mar-97 Jul-98 Dec-99 Apr-01 Sep-02 Jan-04

Date

mg TP / L

TP Values

Annual Median

Figure 4.13 Total Phosphorus Data for Haldeman Creek 1990 – 2002
29

Fecal and Total Coliforms Haldeman Creek

0

2000

4000

6000

8000

10000

12000

Oct-89 Jul-92 Apr-95 Jan-98 Oct-00 Jun-03

Date

Counts / 100 ml

Fecal Coliforms

Total Coliforms

Figure 4.14 Fecal and Total Coliform Counts from Haldeman Creek

4.4 Rock Creek

The sparse sampling record, the result of an inconsistent sampling program, includes 32 samples

with 10 dates before 1990 and 22 dates between 1990 and 1997. The available data (Table 4.1) indicate 

relatively low water quality: Dissolved oxygen less than 4.0 mg/L occurred in 45% of the samples

collected over the 10 years of available data. Nutrient concentrations were relatively high through the 

period, and maximum values for the parameters shown in Table 4.1 all indicate affected conditions. 

Table 4.1 Summary of Selected Water Quality Data for Rock Creek

Parameter n Min 25th % Median Mean 75th% Max

salinity 54.00 0.00 0.00 2.25 9.55 17.95 32.90

D.O. 70.00 0.55 2.73 4.40 4.30 6.00 9.15

Turbidity 73.00 0.30 1.40 2.40 2.73 3.05 13.19

TP 35.00 0.02 0.06 0.10 0.13 0.18 0.33

TN 51.00 0.10 0.61 0.70 1.46 0.98 32.00

NH4 55.00 0.00 0.03 0.08 0.10 0.16 0.37

Chlor a 40.00 0.17 2.10 5.30 8.31 8.78 58.00
30

4.5 Golden Gate Canal

The Golden Gate Canal data set shows two breaks in the record of data since the early 1970s. 

Little sampling occurred in the late 1980s and between 1992 and 1996. Data from the larger system,

combined with data near the weir, provided data for analysis of historic conditions. Across the period of 

record, salinity varied seasonally and with depth. Values near zero between June and November increased 

to near marine conditions (30 ppt) during winter and spring months. Turbidity remained low in the data 

record, with a median value of 2.2 NTU and a maximum value of 12 NTU between 1978 and 2002. 

More frequently collected Total Nitrogen (TN) -and or Total Kjeldahl Nitrogen (TKN) data

provided a large data record for review. TN and TKN data collected between 1996 and 2002 showed

lower annual median values than the preceding 20 years of data (Figure 4.15). Little change in total

phosphorus levels occurred (Figure 4.16), but greater numbers of high chlorophyll a values (> 10 mg / 

m

3

) have occurred over the past 10 years compared to earlier data (Figure 4.17). 

Dissolved oxygen levels (Figure 4.18) have exceeded the water quality criterion (4 mg/L)

throughout the period of record. Data before 1998 indicate either no sample depths or record depths of 

“0”, indicating a surface sample. Dissolved oxygen data collected deeper in the water column (0.1 to 2.7 

m) are included after that point. A correlation of 0.2 between depth and dissolved oxygen occur for that 

period. A difference in recent dissolved oxygen data is the occurrence of extremely high oxygen

concentrations, correlated with high chlorophyll a values. 

Fecal coliform counts (Figure 4.19) exceeded water quality standards (>400 counts) a number of 

times across the period of record. However, data since 1995 include most of the values greater than 1,000 

counts. The faction of samples exceeding 400 counts/100 ml increased in recent years. More frequent

sampling may provide clear evidence of a water quality exceedance condition that has occurred

throughout the period of record for this tributary. 
31

TN or TKN Golden Gate Canal

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Mar-71 Aug-76 Feb-82 Aug-87 Jan-93 Jul-98 Jan-04

Date

mg TN or TKN / L

TN or TKN values

Annual Median Values

Figure 4.15 Total Nitrogen and TKN Values and Annual Median Values for Golden Gate Canal Stations

TP Golden Gate Canal

0

0.25

0.5

0.75

1

1.25

1.5

Mar-71 Aug-76 Feb-82 Aug-87 Jan-93 Jul-98 Jan-04

Date

mg TP / L

TP values

Annual Median TP

Figure 4.16 All TP Values and Annual Median TP Values for Golden Gate Canal Stations
32

Chlorophyll a Golden Gate Canal

0

10

20

30

40

50

60

Apr-89 Dec-91 Sep-94 Jun-97 Mar-00 Dec-02

Date

mg Chlor a / m3

Figure 4.17 Chlorophyll a Values for Golden Gate Canal Stations

Dissolved Oxygen Golden Gate Canal

0

2

4

6

8

10

12

14

16

Apr-68 Oct-73 Apr-79 Sep-84 Mar-90 Sep-95 Feb-01

Date

mg DO / L

All Values

Annual Median

Figure 4.18 Dissolved Oxygen Values and Annual Medians for Golden Gate Canal Stations
33

Fecal Coliform Counts Golden Gate Canal

1

10

100

1000

10000

Mar-71 Aug-76 Feb-82 Aug-87 Jan-93 Jul-98 Jan-04

Date

Counts / 100 ml

Figure 4.19 Fecal Coliform Counts, Golden Gate Canal Stations

4.6 Gordon River Tributaries

Gordon River tributary sampling occurred only 10 times between 1970 and 1990. No sampling 

occurred in this area during most of the 1990s. The insufficient data could not provide insight into 

changes in conditions over time. 

4.7 Lely Canal 

Lely Canal water quality sampling between 1979 and 1998 yielded samples from four stations, 

with almost all the data provided by the at the intersection of Lely Canal and US 41. Sampling also 

occurred on five dates in the mid-1990s at a station midway in the main canal reach and at a station near 

the Intracoastal Waterway. Salinity and conductivity samples indicated a relatively freshwater (<1 ppt to 

5 ppt salinity) canal except at the canal’s mouth where salinity varied from about 13 ppt to 27 ppt over the 

period of record. Water clarity (secchi disk depth) remained high across the data record (median 0.8 m).

Fecal coliform, total coliforms and dissolved oxygen regularly (20%, 22% and 30% of sample values 

respectively) exceeded water quality standards. Exceedances were sufficient to consider the canal

impaired under Florida impaired water criteria. Current annual median D.O values (Figure 4.20) suggest a 
34

continuing decline in D.O. conditions over the period of record. Total Kjeldahl Nitrogen concentrations 

may have declined some over the past decade (Figure 4.21). Total phosphorus concentrations however, 

appear to have changed little over time (Figure 4.22). 

Dissolved Oxygen Lely Canal

0

5

10

15

20

Nov-78 Dec-82 Jan-87 Mar-91 Apr-95 May-99 Jun-03

Date

mg D.O. / L

All Values

Annual

Figure 4.20 Dissolved Oxygen, Lely Canal Stations

TKN Lely Canal

0

0.5

1

1.5

2

2.5

3

3.5

Nov-78 Dec-82 Jan-87 Mar-91 Apr-95 May-99 Jun-03

Date

mg TKN / L

All values

Annual Median

Figure 4.21 Total Kjeldahl Nitrogen Lely Canal Stations
35

TP Lely Canal

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

Nov-78 Apr-84 Oct-89 Apr-95 Oct-00

Date

mg TP / L

All Values

Annual Median

Figure 4.22 Total Phosphorus, Lely Canal Stations
36

5.0 HYDRAULIC – WATER QUALITY MODELING DATA GAP EVALUATION 

5.1 Introduction

Review of the final data set and summary statistics of those data focused on questions related to 

water quality modeling and long-term monitoring efforts

• Were station locations appropriate to support water quality modeling and long-term 

monitoring?

• Were the data sufficient to provide overall water quality characterization of Naples Bay?

• What data sets were available to evaluate potential trends, either in the bay as a whole or at 

specific locations?

• What changes should Taylor Engineering recommend to meet SFWMD objectives for

modeling and monitoring Naples Bay?

5.2 Data Trends and Water Quality Conditions Gap Analysis

5.2.1 Sampling Stations Location and Periods

The data record for Naples Bay and its tributaries contains several characteristics that limit

statistical trend analysis. Before the current sampling effort, which began at most stations in 1999 or 

2000, sampling occurred at quarterly or more infrequent intervals. Monthly sampling occurred most often 

for a few years and often for only one year. The database contains considerable data from single intensive 

day efforts, repeated months later, for a few years. Consistent temporal sampling patterns are rare in the 

database with respect to the total period of record (1970 – 2002)

The current sampling effort covers most of the bay and some of the tributaries (Figure 5.1). 

Sampling includes 

• Dissolved oxygen, salinity, pH, temperature, secchi disk depth, color, turbidity, total

suspended solids

• Arsenic, calcium, cadmium, chromium, chloride, fluoride, magnesium, lead, sulfate, zinc

• Ammonium, Nitrate+Nitrite, Total Kjeldahl Nitrogen ,Total Phosphorus, orthophosphate

• Chlorophyll a and Phaeophytin, Fecal and Total Coliform

• Samples collected at the surface supplemented at some stations with deeper water column 

field parameter measurements.
!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(!(

!(

BC1

BC5

BC4

BC3

BC2

NBAY50

NBAY41

NBAY24

NBAY22

NBAY20

GORD60

ROOK465

GGCAT31

HALDCRK

ROOK464

ROOK463

28030048

28030047

28030031

28030030

LELY CANAL

GOLDEN GATE MAIN CANAL

GORDON

RIVER

TAMIAMI CANAL

A RI PORT ROAD CANAL

HALDEMAN CREEK

I-75 CANAL

Figure 5.1 Current Sampling Stations and Recommended Station Additions

LEGEND

River

Creek

Primary Canal

Tertiary Canal

!( Current Sampling Stations

Recommended Sampling Stations

!( Water Quality

!( Tide Gage

0 1 2

Miles

·

37
38

5.3 Water Circulation and Water Quality Modeling

5.3.1 Introduction

Taylor Engineering proposes a two-dimensional hydrodynamic and water quality model for

evaluation of water quality in Naples Bay. The level of complexity represented in a two-dimensional 

model should provide spatial and temporal dynamics necessary to understand, simulate, and predict water 

quality conditions at the necessary spatial and temporal scales. This class of model should provide the 

most cost-effective solution to the challenge of developing a long-term water quality managementplanning tool in a relatively short period. 

The physical complexity and size of Naples Bay clearly indicate that a one-dimensional model 

(such as CSTR or a continuously stirred tank reactor simulation model) would not adequately describe or 

predict the range of water quality conditions found in Naples Bay. However, available hydraulic and

water quality data are inadequate for use in a three-dimensional model. Almost all the data represent 

surface conditions. Multi-depth water quality data, necessary to understand changes through the water 

column, were unavailable. Further, no velocity measurements (were available. These two factors would 

constrain modeling efforts in the near future to two dimensions. Therefore, Taylor Engineering evaluated 

the hydraulic and water quality data gaps to identify the requirements of a two-dimensional model. Twodimensional modeling would provide the circulation and water quality variation with respect to time and 

space. Model results would include depth-averaged values of a parameter (e.g., velocity for circulation 

and DO for water quality) at any given point in the model domain and at any time during the model

simulation period. A two-dimensional model cannot provide the variation of a parameter along the

vertical axis and thus would not simulate a condition such as a salt wedge.

Data requirements for two-dimensional water circulation and water quality modeling include at 

least tidal data, flows from tributary sources, and runoff data (typically developed from rainfall).

Sufficient data exist to set up and calibrate a model (limited hydraulic model calibration) for the year 

2001. Ongoing monthly sampling efforts at key points in the bay and tributaries would provide much of 

the necessary data for model validation (Figure 5.1). However, calibrating the models in detail would 

require intensive hydraulic and water quality monitoring. 

5.3.2 Data for Physical Forcing in the Model

Tidal circulation provides the primary driving force for water circulation and transport of

pollutants within the study area. Secondary forcing mechanisms include wind shear and pollutant
39

dispersion. Therefore, to simulate the water quality in the bay, an hydraulic model must first adequately 

simulate the tidal circulation in the area. The hydraulic model would require stage or flow input values at 

its boundaries (measured stage or computed flow). Depending on the modeling software, the input data 

set may also include (or require) wind data for hydraulic simulation. The water quality model would 

likewise require water quality parameter input values (measured water quality data) at its boundaries and 

estimates of loadings within its model domain. Independent estimates could provide pollutant loadings. 

Dispersion is a well-described physical mechanism built into current water quality models. Most models

require only the specification of a dispersion rate.

5.3.3 Model Domain

For this project, Taylor Engineering assumed Naples Bay as the primary area of interest for

modeling. Secondary areas of interest included the Gordon River Extension and Lely Canal. Given these 

areas of interest, the available data suggested a model domain extending from SFWMD flow station 

16019 in Golden Gate Canal to the Gordon River Extension weir at the north end of the bay and to the

confluence of Marco River and the Gulf of Mexico south of the project area. The domain would also 

include a portion of the Gulf of Mexico adjacent to the City of Naples and would extend east to the road 

crossings over Rock Creek (at Highway 31), Haldeman Creek (at US 41), Lely Canal (at US 41), and 

Henderson Creek at Tamiami Trail. The model domain would extend south to Marco River because the 

Intracoastal Waterway (IWW) interconnects areas (i.e., Dollar Bay, Shell Bay, etc.) south of Naples Bay. 

Given the unlikely availability of tidal and water quality data along the IWW, locating the south boundary 

to Marco River allows application of Gulf tidal data as a model boundary. Further, the areas south of 

Naples Bay could convey water to and from Naples Bay and significantly affect water quality. Future 

diversions from Golden Gate Canal through creeks draining to these areas would increase local pollution 

loading and redistribute pollution loading in Naples Bay. These factors strongly encourage inclusion of 

these areas in the model domain.

5.3.4 Model Elevation Data

Bathymetric data from the survey in Task 1 of this project would provide the primary elevation 

data for the model setup. Inclusion of bulkhead survey data for the major canal systems would complete 

the data necessary for model bathymetric setup in the area of interest. Earlier survey data, nautical charts, 

and topographic maps might supplement the survey data to provide elevation data for the extensive model 

domain outside the area of interest.
40

5.3.5 Model Input Data

The hydraulic and water quality models would require input data for all periods of model

simulations at the following points as a minimum (Figure 5.2): 

• Stage and water quality at the Gulf of Mexico boundary (Gordon Pass and the confluence of 

Marco River and Gulf)

• Flow (or stage) and water quality at Station 16019 (Golden Gate Canal)

• Flow (or stage) and water quality at Gordon River Extension weir, Lely Canal, Rock Creek, 

Haldeman Creek, and Henderson Creek

The hydraulic water quality model requires an intensive calibration dataset. Forty-eight-hour 

hydraulic and water quality measurements made during the dry and wet seasons would provide sufficient 

calibration information. Needed information would include:

• Stage and velocity measured hourly at the hydraulic monitoring stations. 

• Water quality parameters of interest to include temperature, salinity, dissolved oxygen,

turbidity, nitrogen species (TKN and nitrite+nitrate), total phosphorus, dissolved

orthophosphorus, and chlorophyll a measured either hourly or once every six hours.

• Proposed stations for intensive hydraulic and water quality calibration monitoring (Figure

5.2) include:

o Golden Gate Canal weir, Gordon River Extension weir, Rock Creek, Haldeman Creek, 

Lely Canal and Henderson Creek (weir stage measurements where available, or stage 

and velocity measurements in the absence of a weir).

o US 41 crossing over Gordon River (stage, velocity, and water quality measurements)

o A point of constriction in the bay south of the US 41 crossing (stage, velocity, and

water quality measurements)

o A location at the south end of the project area (stage and velocity monitoring only)

o Gordon Pass (stage, velocity, and water quality measurements)

o Confluence of Marco River and the Gulf of Mexico (stage data only)

To provide an optimal dataset to verify the model performance, Taylor Engineering recommends

a yearlong hydraulic and water quality data monitoring at the model’s external boundaries and at specific 

points within the bay. Water quality data collected at least every two weeks would provide an ideal basis 
41

to verify water quality predictions. Six-hour average flow at Station 16019 and hourly stage measurement 

at the other stations would provide sufficient resolution to simulate tidal circulation. Measured stage or 

rainfall would provide estimates of flows from Golden Gate Canal weir, Gordon River Extension weir, 

Rock Creek, Haldeman Creek, Lely Canal, and Henderson Creek. Available rainfall data would provide 

the basis to estimate flows and chemical loads from the contributing watersheds to the bay. Water quality 

sampling at watershed discharge points would provide model validation data. 

5.3.6 Available Hydraulic Data

Hydraulic modeling requires either flow or stage data at the model boundaries for the entire

simulation period. In the absence of flow data, a runoff model could simulate flow based on rainfall data. 

Available hydraulic data (Tables 5.1, 5.2, and 5.3: metadata from SFWMD DBHYDRO database) would 

include rainfall, stage, and flow measurements.

A comparison of the periods of record of the rainfall, stage, and flow data in Tables 5.1, 5.2, and 

5.3 indicated that concurrent measurement of these variables sufficient for hydraulic modeling occurred 

from January 25, 2001 to June 19, 2002. More recent data from the recommended stations will become 

available in the DBHYDRO database. The addition of this data will extend the period of concurrent

measurements.

The available concurrent flow data (computed from stage data) comes from:

• Golden Gate Canal Weir (Collier County Station DOS536)

• Gordon River Extension weir (DBHYDRO: Dbkey FI256)

• Lely Canal at US 41 (DBHYDRO: Dbkey 16044)

• Henderson Creek at Tamiami Trail (DBHYDRO Dbkey FI251)

Flow data from these stations could serve as the flow boundaries for the hydraulic model.

Concurrent rainfall data from SFWMD COLGOV_R station would provide the means to estimate 

the runoff flows from Rock Creek. Given the drainage area of the creek, rainfall-runoff modeling could 

provide the time series of flows from the creek’s upstream boundary. SFWMD HALDEMAN_T would 

provide the stage boundary condition at Haldeman Creek at the US 41 model boundary.
42

Along the model’s western boundary, concurrent stage data from NOAA 8725110 would provide 

a continuous record of water surface elevation for the model boundary along the Gulf. DBHYDRO could

provide stage data for stations along Henderson Creek.

Tidal gauges could provide good model calibration data. However, as of this writing, no available 

stage data occur within the model domain from January 25, 2001 to June 19, 2002. Therefore, published 

tidal ranges at the bay could provide limited model calibration. Addition of tidal gauges in the bay (Figure 

5.1) would allow a detailed calibration of the tidal behavior of a two-dimensional model.

5.3.7 Recommended Water Quality Data Collection

The insufficient water quality data from the present sampling program preclude calibration of the 

water quality model. Further, the data cannot support a process level water quality model that might

simulate fluctuations in dissolved oxygen. However, the data should suffice for most of the necessary

water quality model verification data for a two-dimensional model of the bay. The data from present 

sampling programs (Figure 5.1) would provide comparison information to evaluate errors in water quality 

model performance over the simulation period or periods. Additional water quality stations recommended 

for better water quality model verification would include the following station locations (Figure 5.1):

• Just inside Gordon Pass, 

• Within the main passages from residential canal areas on the west side of the bay,

• In the main body of the bay south of Gordon Inlet 

• In the IWW at the mouth of Lely Canal

• At a constriction near the mouth of Henderson Creek
!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

!(

Golden Gate Canal

Henderson Creek

Rock Creek

Haldeman Creek

Gordon Pass

Lely Canal

Gordon River

H

e

n

d

ers

o

n

Cre

e

k

C

a

n

al

I-75 Canal

Tamiami Canal

LELYUS41

NAPLES_R

COLGOV_R

GOLD.W1_W

GOLD.W1_H

GORDON 2_H

HENDTAMI_H

HALDEMAN_T

Gulf of Mexico

0 1 2

Miles

·

LEGEND

!( Rain

!( Stage

!( Flow

!( Intensive Calibration

Figure 5.2. Locations for Water Circulation and Water Quality Model Calibration Data

43
44

5.4 Summary of Recommendations

Taylor Engineering envisions the use of a two-dimensional model to simulate long-term water 

circulation and water quality dynamics. This class of model would likely provide sufficient capability to 

simulate ambient water quality conditions for management of the bay to achieve and maintain Class III 

water quality standards. However, calibrating the model would require additional sampling and data

collection. Additional long-term sampling stations would likely increase the ability to verify model

performance, develop management plans, and monitor changes in the system.

Sufficient hydrologic data collected since 2000 from currently active hydrologic stations provide 

sufficient information for use in developing a limited calibrated water circulation model. Rainfall, flow at 

Golden Canal weir, and the Gordon River Extension weir, stage measurements from Haldeman Creek, 

Rock Creek, Lely Canal, Henderson Creek, and from gauges in the Gulf of Mexico would provide most 

of the data. Taylor Engineering recommends runoff modeling to provide stormwater flows from

developed areas of the watershed, particularly the City of Naples.

Given the absence of tide gauges in Naples Bay, published tidal ranges would substitute for direct 

measurement to provide a limited calibration of the hydraulic model. The addition of several tide gauges 

would greatly improve hydraulic model calibration and verification capabilities 

Intensive 48-hour hydraulic and water quality parameter measurements during the dry and wet

seasons would provide the ideal data sets for a detailed calibration of the hydraulic and water quality 

models.

Data from monthly sampling efforts in the bay, augmented by data from recommended additions 

to the current sampling network, would provide verification data for the hydraulic and water quality

model. The recommended sampling stations would suffice for verification of the model calibration and 

simulation period performance testing. The new stations would extend the monitored area south to

Henderson Creek, potentially affected by proposed changes in the Naples Bay watershed canal drainage 

system.
45

Table 5.1 Collier County Rainfall Data

DBKEY STATION GROUP FREQUENCY AGENCY

START 

DATE

END DATE LONGITUDE LATITUDE

PT210 082850-2 82850 Daily NOAA 1-Jan-31 26-Jan-97 -81.3869 25.8456

PT211 082850-2 82850 Daily NOAA 27-Jan-97 28-Dec-01 -81.3869 25.8456

PT308 085359-1 85359 Daily NOAA -81.7139 25.9492

PT328 086076-1 86076 Daily NOAA -81.7753 26.1522

PT445 086078-1 86078 Daily NOAA 1-Jul-48 28-Aug-50 -81.8167 26.1167

PT329 086078-2 86078 Daily NOAA 1-Sep-50 28-Sep-50 -81.8167 26.1500

PT330 086078-3 86078 Daily NOAA 1-Jun-51 28-May-61 -81.7833 26.1500

PT331 086078-4 86078 Daily NOAA 1-Jun-61 28-Aug-98 -81.7833 26.1667

PT332 086078-5 86078 Daily NOAA 21-Feb-84 6-Jun-84 -81.8000 26.1667

PT333 086078-6 86078 Daily NOAA 1-Sep-98 28-May-00 -81.7883 26.1653

PT334 086078-7 86078 Daily NOAA 1-Jun-00 4-Apr-01 -81.7878 26.1664

PT335 086078-8 86078 Daily NOAA 5-Apr-01 28-Jun-01 -81.7878 26.1667

PT336 086078-9 86078 Daily NOAA 1-Jul-01 28-Dec-01 -81.7158 26.1686

DO534 951EXT_R 951EXT_R Daily WMD 19-Jun-96 1-Jun-04 -81.6884 26.3026

DJ225 ASGROW ASGROW Daily WMD -81.7081 26.2712

5951 BAY WEST_R BAY WEST Daily WMD 26-Apr-80 30-Sep-85 -81.7023 26.2751

DJ226 BCBNAPLE_R BCBNAPLE Daily WMD 1-Dec-90 13-May-97 -81.8081 26.2254

DU536 COLGOV_R COLGOV_R Daily WMD 30-Apr-96 1-Apr-05 -81.7626 26.1298

5978 COLLIER_R COLLIER Daily WMD 30-Sep-81 31-Mar-05 -81.6581 26.1568

OU145 NAPCON_R NAPCON_R Daily WMD 4-Feb-02 2-Apr-05 -81.7878 26.1672

16633 NAPLES_R NAPLES Daily WMD 8-Jan-91 15-Apr-05 -81.7898 26.1681
46

Table 5.2 Collier County Stage Data. with Currently Active Stations in Bold Type

DBKEY STATION GROUP FREQUENCY AGENCY START 

DATE END DATE LONGITUDE LATITUDE

SN319 GG1_H GG1_H Daily WMD 13-Jul-04 22-Sep-04 -81.7742 26.1680

SN321 GG1_T GG1_T Daily WMD 13-Jul-04 22-Sep-04 -81.7742 26.1680

839 GOLD.W1_H GOLD.W1 Daily USGS 31-Mar-77 17-May-80 -81.7672 26.1680

840 GOLD.W1_H GOLD.W1 Daily USGS 1-Oct-67 3-Oct-84 -81.7672 26.1680

841 GOLD.W1_H GOLD.W1 Daily USGS 1-Oct-64 3-Oct-84 -81.7672 26.1680

5382 GOLD.W1_H GOLD.W1 Daily WMD 6-Dec-84 19-Oct-94 -81.7672 26.1680

16019 GOLD.W1_H GOLD.W1 Daily WMD 19-Oct-94 22-Sep-04 -81.7672 26.1680

4278 GORDON 2_H GORDON 2 Daily WMD 9-Oct-80 14-Aug-95 -81.7837 26.1740

4280 GORDON 2_T GORDON 2 Daily WMD 3-Sep-80 30-Oct-89 -81.7837 26.1740

13004 GORDON 2_T GORDON 2 Daily WMD 30-Oct-89 5-Nov-03 -81.7837 26.1740

FI256 GORDON 2_H GORDON 2 Daily WMD 22-Apr-97 6-Oct-04 -81.7837 26.1740

QS282 GORDON 2_T GORDON 2 Daily WMD 5-Nov-03 6-Oct-04 -81.7837 26.1740

MQ906 HALDEMAN_T HALDEMAN Daily WMD 25-Jan-01 21-Oct-04 -81.7620 26.1240

P6258 NAPLE_T NAPLE_T Daily WMD 2-Nov-00 6-Oct-04 -81.7668 26.1815

5530 GOLD.W2_H GOLD.W2 Daily WMD 28-Apr-83 20-Oct-94 -81.7348 26.1684

8725110 Gulf of Mexico 6-minutes NOAA 1-Jan-96 31-Jan-05 -81.8067 26.1300

8725114 Naples Bay 

North

Daily NOAA 1-Apr-78 31-Aug-78 -81.7883 26.1367

16044 LELYUS41 LELYUS41 Daily WMD 20-Jan-95 15-Mar-05 -81.7462 26.1040

FI256 GORDON 2_H GORDON 2 Daily WMD 22-Apr-97 06-Apr-05 -81.7837 26.1740

FI251 HENDTAMI_H HENDTAMI Daily WMD 14-May-97 28-Mar-05 -81.6890 26.0587
47

Table 5.3 Collier County Flow Data

DBKEY STATION GROUP FREQUENCY AGENCY START 

DATE

END DATE LONGITUDE LATITUDE

842 GOLD.W1_W GOLD.W1 Daily USGS 1-Oct-64 3-Oct-84 -81.767180 26.167968

5386 GOLD.W1_W GOLD.W1 Daily WMD 29-Oct-89 30-Dec-97 -81.767180 26.167968

6518 GOLD.W1_W GOLD.W1 Daily USGS 27-Aug-81 13-Sep-84 -81.767180 26.167968

DO536 GOLD.W1_W GOLD.W1 Daily WMD 30-Sep-91 19-Jun-02 -81.767180 26.167968
REFERENCES

Janicki Environmental, Inc. 2003. Water Quality Data Analysis and Report for the Charlotte 

Harbor National Estuary Program. Prepared for: Charlotte Harbor National Estuary 

Program, North Fort Myers, Florida.
APPENDIX A

Station Names, Locations, and Periods of Record
Station Code Station_NA Location Start Date End Date

3495 GOLDEN GATE CANAL AT C.R. 31 Golden Gate Canal 12/14/1998 8/13/2002

2291300 GOLDEN GATE CANAL AT NAPLES, FLA Golden Gate Canal 11/27/1965 12/3/1979

28030038 GOLD GATE CAN SR 951 BR Golden Gate Canal 4/3/1973 7/10/1991

28030053

GOLDEN GATE CANAL BETWEEN SR31/I75UPSTREAM 

OF Golden Gate Canal 12/22/1988 12/11/1991

AIRPORT886 Golden Gate Canal Basin Golden Gate Canal 12/4/1991 8/19/1997

BC4

Downstream weir in Golden Gate Canal across from Bear's Paw 

Country Club Golden Gate Canal 10/18/2000 6/19/2002

GGCAT31 Bridge at intersection of Airport Rd and Golden Gate Canal Golden Gate Canal 1/17/1979 6/6/2002

2291280 GORDON RIVER AT NAPLES,FLA Gordon River 10/26/1970 9/11/1980

28030047 GORDON R ABOVE WIER 951 Gordon River 8/30/1972 9/11/2002

28030048 GORDON R BEMBURY CANAL Gordon River 8/30/1972 9/28/1989

BC3 Gordon River Ext. at mouth of canal leading to Main Post Office Gordon River 10/18/2000 6/19/2002

GORDONRV

Bridge at intersection of Golden Gate Pkwy and Gordon River 

Extension Gordon River 7/6/1981 12/19/1988

GRESTA10 Gordon River 7/15/1997 7/15/1997

10 Gulf 10/27/1993 11/15/1999

9573 US Fish & Wildlife Service Gulf 8/19/1957 11/14/1957

COLLIER316 NAPLES PIER Gulf 6/18/2001 6/18/2001

COLLIER55 LOWDERMILK PARK BEACH Gulf 6/18/2001 6/18/2001

ROOK465 Gulf 1/26/1999 12/17/2002

3 Haldeman Creek 10/27/1993 11/15/1999

6 Haldeman Creek 10/27/1993 11/15/1999

28030029 NAP BAY HALD CK Haldeman Creek 8/30/1972 8/18/1975

BC5 Bridge at intersection of Haldeman Creek and Bayshore Dr. Haldeman Creek 10/18/2000 6/19/2002

HALD32 Haldeman Creek at end of Palm Lane Haldeman Creek 4/16/1992 9/22/1992

HALDCRK

Upstream of amil gate at intersection of US41 and Haldeman 

Creek Haldeman Creek 12/5/1989 8/20/1997

HALDNB Junction of Haldeman Creek and Naples Bay Haldeman Creek 4/16/1992 8/22/1996

LELY Bridge at intersection of US41 and Lely Main Canal Lely Canal 12/5/1989 6/15/1998

LELYICW Lely Canal 4/24/1996 8/22/1996

LMAIN2 Lely Canal 12/20/1995 8/27/1996

4 Lower Bay 11/27/1993 11/15/1999

5 Lower Bay 10/27/1993 11/15/1999

7 Lower Bay 10/27/1993 11/15/1999

8 Lower Bay 10/27/1993 11/15/1999

9 Lower Bay 10/27/1993 11/15/1999

28030004 Lower Bay 1/5/1971 7/28/1975

28030033 NAP BAY YACHT BASIN Lower Bay 8/30/1972 4/11/1990

28030034 NAP BAY CAN BETW PEL & BL PT Lower Bay 7/6/1972 6/7/1976

28030035 NAP BAY JAYCEE PK Lower Bay 8/30/1972 9/28/1989

28030050 NAPLES BAY CANAL BETW ENDS KINGF Lower Bay 8/30/1972 8/18/1975

260700081472800 NAPLES BAY (FCD STATION) Lower Bay 9/8/1978 9/8/1978

BC1 Channel Marker 38 in Naples Bay Lower Bay 10/18/2000 6/19/2002

COL-COL10-017 Collier-COL10-017 Lower Bay 4/10/2001 4/10/2001

COL-COL10-034 Collier-COL10-034 Lower Bay 2/5/2001 2/5/2001

COL-COL10-041 Collier-COL10-041 Lower Bay 5/23/2001 5/23/2001

COL-COL3-939 Collier-COL3-939 Lower Bay 5/23/2001 5/23/2001

COL-COL3-964 Collier-COL3-964 Lower Bay 12/19/2000 12/19/2000

COL-COL3-965 Collier-COL3-965 Lower Bay 4/10/2001 4/10/2001

COL-COL5-889 Collier-COL5-889 Lower Bay 4/10/2001 4/10/2001

COL-COL5-903 Collier-COL5-903 Lower Bay 2/5/2001 2/5/2001

COL-COL5-907 Collier-COL5-907 Lower Bay 5/23/2001 5/23/2001

COL-COL6-617 Collier-COL6-617 Lower Bay 4/10/2001 4/10/2001

COL-COL6-631 Collier-COL6-631 Lower Bay 2/5/2001 2/5/2001

COL-COL6-633 Collier-COL6-633 Lower Bay 5/23/2001 5/23/2001

COL-COL7-009 Collier-COL7-009 Lower Bay 4/10/2001 4/10/2001

COL-COL7-988 Collier-COL7-988 Lower Bay 5/23/2001 5/23/2001

COL-COL7-998 Collier-COL7-998 Lower Bay 2/5/2001 2/5/2001

COL-COL8-972 Collier-COL8-972 Lower Bay 4/10/2001 4/10/2001

COL-COL8-973 Collier-COL8-973 Lower Bay 2/5/2001 2/5/2001

COL-COL8-986 Collier-COL8-986 Lower Bay 5/23/2001 5/23/2001

COL-COL9-716 Collier-COL9-716 Lower Bay 4/10/2001 4/10/2001

COL-COL9-742 Collier-COL9-742 Lower Bay 2/5/2001 2/5/2001

COL-COL9-775 Collier-COL9-775 Lower Bay 5/23/2001 5/23/2001

COLLIER57 GORDONS PASS Lower Bay 6/18/2001 6/18/2001

COL-NA-ESBAY-1 Collier-Naples Bay-1 Lower Bay 4/25/2001 8/23/2001

COL-NA-ESBAY-2 Collier-Naples Bay-2 Lower Bay 4/25/2001 8/23/2001

Page 1
Station Code Station_NA Location Start Date End Date

COL-NA-ESBAY-3 Collier-Naples Bay-3 Lower Bay 4/25/2001 8/23/2001

DOLLAR15 Dollar Bay at Marker 68 Lower Bay 4/15/1992 9/21/1992

GORD10 Lower Bay 4/11/1989 9/21/1992

NBAY20 Naples Bay at Channel Marker 21 Lower Bay 4/16/1992 9/21/1992

NBAY22 Naples Bay at entrance to Treasure Cove Lower Bay 4/15/1992 12/2/1992

NBAY24 Naples Bay at Marker 24 Lower Bay 4/18/1990 8/22/1996

NBAY41 Naples Bay at mouth of canal entering Royal Harbor Lower Bay 4/13/1992 9/22/1992

NBAY50 Naples Bay at Marker 31 Lower Bay 4/13/1992 9/22/1992

NTK200120 N 10K Islands - Naples Bay Lower Bay 10/18/2000 6/19/2002

NTK200121 N 10K Islands - Naples Bay Lower Bay 7/13/2001 7/13/2001

NTK200121_B N 10K Islands - Naples Bay Lower Bay 10/5/2001 10/5/2001

ROOK463 Naples Bay south of Gordon Pass Lower Bay 1/26/1999 12/17/2002

ROOK464 Lower Bay 1/26/1999 12/17/2002

28030032 NAP BAY ROCK CK Rock Creek 8/30/1972 9/28/1989

ROCK62

Located at junction of Rock Creek and Harbor Lane adjoining 

the Brookside Subdivision Rock Creek 4/13/1992 8/22/1996

ROCKE Rock Creek Rock Creek 12/5/1991 8/21/1997

ROCKW Rock Creek Rock Creek 12/5/1991 8/20/1997

119001 EV-GAC CORP CANAL CROSSING-NAPLE GGC Tributaries 3/5/1970 3/25/1970

119002 EV-GAC CNL CROSSING-GOLDEN GATE GGC Tributaries 3/5/1970 3/25/1970

119003 EV-GAC CNL NR GOLDEN GATE ESTATE GGC Tributaries 3/5/1970 3/25/1970

119004 EV-GAC CNL RD TO PRODUCE COMPANY GGC Tributaries 3/5/1970 3/25/1970

2291393

COCOHATCHEE RIVER CANAL AT WILLOUGHBY ACRE 

BRIDG Tributaries 5/19/1970 10/10/1979

261009081411400 GOLDIN GATE CA E OF NAPLES, FLA Tributaries 1/20/1972 1/24/1979

261335081352400 10B GORDON RIVER CANAL AT NAPLES FLA Tributaries 10/26/1970 1/24/1979

28020265FTM Cocohatchee River at Immokalee Rd and Palm River Blvd Tributaries 9/13/2000 8/20/2002

9CN@GGBL Golden Gate Canal Basin Tributaries 12/16/1996 8/21/1997

ARN@VAND Golden Gate Canal Basin Tributaries 12/12/1996 8/18/1997

ARS@896 Golden Gate Canal Basin Tributaries 12/9/1996 8/18/1997

BC15 Airport Rd. Canal at entrance to Sam's Club GGC Tributaries 10/17/2000 6/20/2002

BC23

Bridge at intersection of Main Golden Gate Canal and CR951 

(GGCAT951) Tributaries 10/25/2000 6/6/2002

BC26

Intersection of 951 Canal and Immokalee Rd. Canal 

("COCAT951") Tributaries 10/25/2000 4/3/2002

BRYPUMSW

Surface Water Site on Townsend Canal Downside Berry Grove 

Pump Station GGC Tributaries 9/19/2002 3/5/2003

COCAT951

COCOHATCHEE CANAL AT THE JUNCTION OF S.R. 951 

AND S.R. 846 Tributaries 1/17/1979 8/18/1998

COCEOF31 Golden Gate Canal basin Tributaries 12/7/1989 6/15/1998

COCPALM

Bridge at Intersection of Palm River Drive and Coconut Palm 

River Tributaries 12/7/1989 8/18/1998

CORK@846 Bridge at intersection of Corkscrew Canal and CR846 Tributaries 12/12/1996 6/11/2002

CYPR@GGB Golden Gate Canal basin Tributaries 12/16/1996 8/21/1997

D2886 Golden Gate Canal basin Tributaries 12/4/1991 8/18/1997

GCB01@20 Golden Gate Canal Basin Tributaries 12/10/1996 8/19/1997

GCB02@SUN Golden Gate Canal Basin Tributaries 12/10/1996 8/19/1997

GGC@858 Bridge at intersection of Golden Gate Canal and CR858 Tributaries 12/16/1996 6/11/2002

GGC@GGBE Golden Gate Canal Basin Tributaries 12/16/1996 8/21/1997

GGC@WHITE Golden Gate Canal Basin Tributaries 12/16/1996 8/21/1997

GGC05@23 Golden Gate Canal Basin Tributaries 12/16/1996 8/21/1997

GGC10 Golden Gate Canal Basin Tributaries 12/4/1991 8/19/1997

GGC14 Golden Gate Canal Basin Tributaries 12/4/1991 8/18/1997

GGCAT951 Bridge at intersection of Main Golden Gate Canal and CR951 Tributaries 1/17/1979 8/19/1997

LP-BEACH LAKES PARK - Beach Tributaries 1/14/1992 7/15/1992

LP-BIRD LAKES PARK - Bird Tributaries 1/14/1992 7/15/1992

LP-IONA LAKES PARK - Iona Tributaries 5/11/1989 10/6/1999

LP-RAMP LAKES PARK - Ramp Tributaries 1/14/1992 7/15/1992

LP-SIGN LAKES PARK - Sign Tributaries 1/14/1992 7/15/1992

MGG03@32 Golden Gate Canal Basin Tributaries 12/10/1996 8/19/1997

ORANGETR Golden Gate Canal Basin Tributaries 12/12/1996 8/20/1997

PIPERS Golden Gate Canal Basin Tributaries 6/23/1992 8/18/1998

QUAILCK Golden Gate Canal Basin Tributaries 9/21/1992 8/18/1998

ROYALP Gordon River Extension basin Tributaries 12/4/1991 8/20/1992

WILSON846 Golden Gate Canal Basin Tributaries 12/9/1997 8/18/1998

126801 SEA GATE CANAL AT MOUTH GR Tributaries 10/19/1977 10/20/1977

126802 SEA GATE CANAL AT MOUTH LAST ARM GR Tributaries 10/19/1977 10/20/1977

126803 CLAM BAY AT CONNECTOR TO DOCTORS Tributaries 10/19/1977 10/20/1977

126804 SEA GATE CANAL AT DEAD END GR Tributaries 10/19/1977 10/20/1977

Page 2
Station Code Station_NA Location Start Date End Date

126805 CLAM BAY NEAR SEA GATE CANAL GR Tributaries 10/19/1977 10/20/1977

126810 CANAL DEAD END DOCTORS BAY GR Tributaries 10/20/1977 10/20/1977

126811 CANAL DEAD END DOCTORS BAY GR Tributaries 10/19/1977 10/20/1977

126813 DOCTORS BAY AT CONNECTOR TO CLAM GR Tributaries 10/19/1977 10/20/1977

126815 DOCTORS BAY OVERWATER STRUCTURE GR Tributaries 10/19/1977 10/20/1977

126816 DOCTORS BAY OVER WATER STRUCTURE GR Tributaries 10/19/1977 10/20/1977

COL-CL-YWEST-3 Collier-Clam Bay West-3 Tributaries 3/1/2001 12/12/2002

GRE896 Gordon River Extension at Pine Ridge Rd. Tributaries 12/4/1991 8/20/1992

GREEN@SB Gordon River Extension basin Tributaries 12/9/1996 8/18/1997

GRESTA1 Gordon River Extension basin Tributaries 10/28/1996 10/28/1996

GRESTA2 Gordon River Extension basin Tributaries 10/28/1996 8/4/1997

GRESTA3 Gordon River Extension basin Tributaries 10/28/1996 8/4/1997

GRESTA4 Gordon River Extension basin Tributaries 10/28/1996 11/20/1996

GRESTA5 Gordon River Extension basin Tributaries 10/28/1996 8/4/1997

GRESTA7 Gordon River Extension basin Tributaries 10/29/1996 8/4/1997

GRESTA8 Gordon River Extension basin Tributaries 10/29/1996 4/21/1997

I75C@VAN Golden Gate Canal basin Tributaries 12/12/1996 8/18/1997

1 Upper Bay 8/31/1994 11/15/1999

2 Upper Bay 8/31/1994 11/15/1999

28030030 NAP BAY GORD R @ PORT AVE Upper Bay 8/30/1972 6/17/1974

28030031 NAP BAY S OF NAP STP EFF Upper Bay 8/30/1972 9/28/1989

28030049 NAPLES BAY 5 AV S BR W Upper Bay 8/30/1972 2/6/1991

260859081472400 10B GORDON RIVER AT US 41 AT NAPLES FLA Upper Bay 10/26/1970 11/15/1999

261147081470400 10B GORDON RIVER AT US 41 AT NAPLES FLA Upper Bay 7/13/1972 7/13/1972

BC2 Just inside the mouth of Rock Creek Upper Bay 4/11/1989 6/19/2002

GORD60 Gordon River at US 41 bridge near Boat Haven Upper Bay 4/13/1992 9/23/1992

GORD70

Gordon River opposite City of Naples Wastewater Treatment 

Plant outfall Upper Bay 4/13/1992 9/23/1992

GORD80

Mid-channel of Gordon River at confluence with reach leading to 

the Conservancy Upper Bay 4/13/1992 9/23/1992

260934081464100 10B NAPLES AIRPORT DRAINAGE CANAL NR NAPLE Upper Bay 3/16/1977 12/3/1979

Page 3
APPENDIX B

Box and Whisker Plots of Individual Station Data Used to Evaluate Current Water 

Quality Conditions in Lower Naples Bay
ROOK463

ROOK464

NTK200120

NTK200121

NTK200121_B

BC1

0

5

10

15

20

25

30

35

40

45

Salinity (%o)

 Median 25%-75% Min-Max 

Figure 1. Box Plots for Salinity Data

ROOK463 ROOK464 BC1 NTK200120

0

5

10

15

20

25

30

35

Temperature (

oC)

 Median 25%-75% Min-Max 

Figure 2. Box Plots for Temperature Data
ROOK463

ROOK464

BC1

NTK200120

Station 9064

Station 9065

Station 9067

Station 9069

Station 9068

0

5

10

15

20

25

30

35

Turbidity (NTU)

 Median 25%-75% Min-Max 

Figure 3. Box Plots for Turbidity Data

BC1 NTK200120

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

Secchi Disk Depth (m)

 Median 25%-75% Min-Max 

Figure 4. Box Plots for Secchi Disk Depth Data
ROOK463 ROOK464 BC1 NTK200120

0

2

4

6

8

10

12

14

16

18

20

22

Dissolved Oxigen (mg/l)

 Median 25%-75% Min-Max 

Figure 5. Box Plots for Dissolved Oxygen Data

ROOK463

ROOK464

NTK200120

BC1

Station 9064

Station 9065

Station 9067

Station 9068

Station 9069

0.00

0.02

0.04

0.06

0.08

0.10

0.12

Total Phosphorus (mg/l)

 Median 25%-75% Min-Max 

Figure 6. Box Plots for Total Phosphorus Data
ROOK463 ROOK464 BC1 NTK200120

0.00

0.01

0.02

0.03

0.04

0.05

0.06

Soluble Reactive Phosphorus (mg/l)

 Median 25%-75% Min-Max 

Figure 7. Box Plots for Soluble Reactive Phosphorus Data

ROOK463

ROOK464

BC1

NTK200120

Station 9064

Station 9065

Station 9067

Station 9068

Station 9069

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

Total Nitrogen (mg/l)

 Median 25%-75% Min-Max 

Figure 8. Box Plots for Total Nitrogen Data
ROOK463

ROOK464

Station 9064

Station 9065

Station 9067

Station 9069

Station 9068

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Ammonia (mg/l)

 Median 25%-75% Min-Max 

Figure 9. Box Plots for Ammonia Data

ROOK463

ROOK464

BC1

NTK200120

Station 9064

Station 9065

Station 9067

Station 9068

Station 9069

0

10

20

30

40

50

60

70

80

90

100

Chlorophyll A (mg/l)

 Median 25%-75% Min-Max 

Figure 10. Box Plots for Chlorophyll A Data
COLLIER57

BC1

NTK200120

Station 9064

Station 9065

Station 9067

Station 9069

Station 9068

0

500

1000

1500

2000

2500

3000

3500

Fecal Coliform (CFU/100ml)

 Median 25%-75% Min-Max 

Figure 11. Box Plots for Fecal Coliform Data

NTK200120

BC1

Station 9064

Station 9065

Station 9067

Station 9069

Station 9068

0

10

20

30

40

50

60

70

80

Total Suspended Solids (mg/l)

 Median 25%-75% Min-Max 

Figure 12. Box Plots for Total Suspended Solids Data
APPENDIX C

Box and Whisker Plots of Individual Station Data Used in to Evaluate Current Water 

Quality Conditions in Upper Naples Bay
BC2

0

5

10

15

20

25

30

35

40

Salinity (%o)

 Median 25%-75% Min-Max 

Figure 1. Box Plots for Salinity Data

BC2

18

20

22

24

26

28

30

32

34

Temperature (

oC)

 Median 25%-75% Min-Max 

Figure 2. Box Plots for Temperature Data
BC2

Station 9052

Station 260859081472400

Station 9062

0

2

4

6

8

10

12

Turbidity (NTU)

 Median 25%-75% Min-Max 

Figure 3. Box Plots for Turbidity Data

BC2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Secchi Disk Depth (m)

 Median 25%-75% Min-Max 

Figure 4. Box Plots for Secchi Disk Depth Data
BC2

0

1

2

3

4

5

6

7

8

9

Dissolved Oxigen (mg/l)

 Median 25%-75% Min-Max 

Figure 5. Box Plots for Dissolved Oxygen Data

BC2

Station 9052

Station 260859081472400

Station 9062

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

0.22

Total Phosphorus (mg/l)

 Median 25%-75% Min-Max 

Figure 6. Box Plots for Total Phosphorus Data
BC2

Station 9052

Station 260859081472400

Station 9062

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

0.22

0.24

Soluble Reactive Phosphorus (mg/l)

 Median 25%-75% Min-Max 

Figure 7. Box Plots for Soluble Reactive Phosphorus Data

BC2

Station 9052

Station 260859081472400

Station 9062

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

Total Nitrogen (mg/l)

 Median 25%-75% Min-Max 

Figure 8. Box Plots for Total Nitrogen Data
BC2

Station 9052

Station 260859081472400

Station 9062

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

0.22

Ammonia (mg/l)

 Median 25%-75% Min-Max 

Figure 9. Box Plots for Ammonia Data

BC2

Station 9052

Station 260859081472400

Station 9062

0

2

4

6

8

10

12

14

16

18

20

22

24

26

28

Chlorophyll A (mg/l)

 Median 25%-75% Min-Max 

Figure 10. Box Plots for Chlorophyll A Data
BC2

Station 9052

Station 260859081472400

Station 9062

0

500

1000

1500

2000

2500

3000

3500

Fecal Colliforms (CFU / 100 mg)

 Median 25%-75% Min-Max 

Figure 11. Box Plots for Fecal Coliform Data

BC2

Station 9052

Station 260859081472400

Station 9062

0

2

4

6

8

10

12

14

16

18

Total Suspended Solids (mg/l)

 Median 25%-75% Min-Max 

Figure 12. Box Plots for Total Suspended Solids Data