LOXAHATCHEE RIVER WATER QUALITY AND BIOLOGICAL MONITORING

TASK 4: FINAL REPORT

ASSESSMENT OF 2009‐2010 LOXAHATCHEE RIVER WATER QUALITY

In Partial Fulfillment of Agreement No. 4600001907

For the Period

October 2009 through September 2010

Respectfully Submitted by

Bud Howard, Lorene Bachman, Susan Noel, David Porter, Jerry Metz,  

Helen Johnson, Abbey Wilkison, Albrey Arrington, Ph.D.

Loxahatchee River District

December 2010
2

Contents

Executive Summary.......................................................................................................................................3

Introduction ..................................................................................................................................................4

Study Area.....................................................................................................................................................5

Materials and Methods.................................................................................................................................6

Results & Discussion ...................................................................................................................................11

Appendix A ‐ Stoplight Decision Rules & Data. ........................................................................................... 29

Appendix B – Box & Whisker Plots.............................................................................................................. 32

Appendix C – Spatial Plots........................................................................................................................... 42

Appendix D – Analysis Methods & Calibration Criteria .............................................................................. 47

Appendix E – Parameter & Station Listing .................................................................................................. 48

Appendix F – Quality Control Summary...................................................................................................... 49

List of Figures

Figure 1.  Loxahatchee River watershed and associated features................................................................ 6

Figure 2.  Loxahatchee River District’s water quality monitoring stations in the Loxahatchee River and

associated waters, color coded by river segment/analysis group................................................................ 9

Figure 3. Plot of daily flow at Lainhart Dam and daily rainfall at LRD for the period of January 2008

through October 2010. ............................................................................................................................... 13

Figure 4.  Synthesis of 2010 water quality stoplight scoring by sampling site for total phosphorus (TP),

total nitrogen (TN), chlorophyll a (CLA), dissolved oxygen (DO), and fecal coliform (FC), Loxahatchee

River, Florida.. .............................................................................................................................................25

List of Tables

Table 1. RiverKeeper sampling sites. .......................................................................................................... 10

Table 2. Summary of annual rainfall and river flows measured at Lainhart Dam.  Lainhart flow data from

SFWMD‐DBHYDRO......................................................................................................................................12

Table 3. A ‘stoplight’ assessment of water quality for Total Nitrogen, Total Phosphorus, and Chlorophyll

a among the seven reaches of the Loxahatchee River for each period October through September

relative to the target levels of 1998‐2002.  See Appendix A for decision rules and data. .........................15

Table 4. Summary of annual geometric mean for total nitrogen by sample station, color coded by

numeric nutrient criteria for Florida streams, or 1998‐2002 target values, Loxahatchee River, Florida...20

Table 5. Summary of annual geometric mean for total phosphorus by sample station, color coded by

numeric nutrient criteria for Florida streams, or 1998‐2002 target values, Loxahatchee River, Florida...21

Table 6. Summary of annual geometric mean for chlorophyll a by sample station, color coded by 1998‐

2002 target values, Loxahatchee River, Florida.......................................................................................... 22

Table 7. Summary of annual geometric mean for dissolved oxygen by sample station, color coded by

1998‐2002 target values, Loxahatchee River, Florida................................................................................. 23

Table 8. Summary of annual geometric mean for fecal coliform bacteria by sample station, color coded

by 1998‐2002 target values, Loxahatchee River, Florida............................................................................ 24
3

Executive Summary

This report presents water quality data collected under the Loxahatchee River District’s

(LRD) RiverKeeper water quality monitoring program.    This monitoring program evaluates 29

water quality parameters at 39 sites throughout the Loxahatchee River watershed and estuary.

Fifteen sites are sampled every month, and the remaining sites are sampled bi‐monthly (every

other month).  The purpose of this program is to identify long‐term trends, assess compliance

with established water quality targets, and establish baseline conditions prior to the

modifications of freshwater inflows resulting from the Comprehensive Everglades Restoration

Project (CERP) and the Northwest Fork Restoration Plan.

This report provides a simplified characterization and overview of water quality

conditions in the Loxahatchee River for the reporting period October 2009 through September

2010, with historical comparisons.  A stoplight analysis (green/good, yellow/caution, red/poor)

evaluating several key parameters to compare the 2010 water quality data to the established

Target Period of 1998‐2002 indicated generally good water quality throughout the watershed.

These findings are encouraging because flows into the river were higher than previous years,

particularly during the dry season. While increased base flows into the river are beneficial,

protecting freshwater dependent species in downstream segments of the river from saltwater

intrusion, increased flows may lead to increased nutrient loading to the system. The results

presented here suggest that increased flows in 2010 did not increase nitrogen and phosphorus

concentrations to detrimental levels, e.g., observed concentrations did not exceed EPA’s newly

published numeric nutrient criteria.  On a less encouraging note, the sampling sites throughout

the watershed continue to exhibit elevated chlorophyll and low dissolved oxygen values relative

to the targets and FDEP criteria.  While two river segments scored a “yellow/caution” level, our

assessment of all sampling sites indicates elevated chlorophyll throughout the watershed.  

Further investigation into the causes and potential consequences of these findings is needed.  

Lastly, several sites in the watershed have consistently scored poorly for more than three key

parameters. Targeted projects should be developed and implemented to improve water quality

at these sites.
4

Introduction

Since 1971 the Loxahatchee River District (LRD) has been fulfilling its mission to preserve

and protect the Loxahatchee River through an innovative wastewater treatment and reuse

program and an active water quality monitoring program.    LRD staff have monitored water

quality in the surface waters of the Loxahatchee River and associated waters (see Figure 1) in

an effort to document the condition and ecological health of the river and to determine the

location and extent of water quality issues that need to be addressed.   Over these past 35

years, the Loxahatchee River District has contributed significantly to the understanding of the

ecology of this river (see http://www.loxahatcheeriver.org/reports.php). While numerous

reports have been written regarding the Loxahatchee River, perhaps none are as

comprehensive as the Restoration Plan for the Northwest Fork of the Loxahatchee River

(SFWMD 2006). This document characterizes the watershed, discusses various restoration

alternatives, and identifies the preferred restoration flow scenario.  In particular, Table 10‐1 of

the restoration plan includes the water quality targets for the marine (salinity >30 ppt),

polyhaline (salinity 18 – 30 ppt), meso/oligohaline (salinity 5 – 18 / 0.5 ‐ 5 ppt), wild and scenic

(salinity <5 ppt), and freshwater tributary (salinity <5 ppt) zones of the Loxahatchee River.  

These water quality targets (i.e., non‐degradation standards) were established by LRD and

SFWMD scientists using bi‐monthly water quality data collected by LRD over the five year

period 1998‐2002.  Using this model, we have expanded the numbers of sites within each of the

above categories and added supplemental river segment or analysis group categories for

Freshwater Canals, and Brackish Tributaries. Figure 2 and Table 1 illustrate water quality

sampling sites, analysis group categories and sampling frequency.

Staff from the Loxahatchee River District’s WildPine Ecological Laboratory collects and

analyzes surface water samples for 29 parameters at 39 sites located in the Loxahatchee River,

its major tributaries, and associated waters (Figure 1). Fifteen sites are sampled every month,

and the remaining sites are sampled bi‐monthly (every other month).    This water quality

monitoring program, entitled “RiverKeeper”, was developed to identify long‐term trends, and

assess compliance with the established water quality targets.    Furthermore, on‐going results

from our water quality monitoring program are used to establish baseline conditions prior to
5

modification of freshwater inflows resulting from the Comprehensive Everglades Restoration

Project and the Northwest Fork Restoration Plan (CERP 2001; SFWMD 2006).  

The purpose of this report is to provide a simplified characterization and overview of the

water quality conditions in Loxahatchee River. We assess and summarize the water quality

throughout the watershed at three levels: first, a high‐level “stoplight” approach by river

segment; second, a temporal and spatial assessment by river segment; and third, annual

comparisons of individual sampling sites relative to target levels.  

Study Area

The Loxahatchee River estuary encompasses approximately 400 ha and drains a

watershed of approximately 700 km2 located in northeastern Palm Beach County and

southeastern Martin County, Florida, USA (Figure 1).    Freshwater discharges into the estuary

from the North Fork, the Northwest Fork, and the Southwest Fork of the Loxahatchee River.

The hydrology of the basin has been substantially altered by flood control efforts since the

1950s.   Historically (pre‐1950), most surface water runoff reaching the estuary originated in

Loxahatchee and Hungryland Sloughs and flowed gradually to the Northwest Fork. In the 1930s

the Lainhart Dam, a small fixed‐weir dam, was constructed in the Northwest Fork at river mile

14.5 to reduce “over” drainage of upstream reaches of the Northwest Fork during dry seasons.  

In 1958 a major canal (C‐18) and flood control structure (S‐46) were constructed to divert flows

from the Northwest Fork to the Southwest Fork, which increased the intensity and decreased

the duration of storm‐related discharge to the estuary. Furthermore, since 1947 Jupiter inlet,

the eastern link to the ocean, was expanded through ongoing dredging projects. These

hydraulic modifications promoted increased saltwater flows into the previously freshwater

portions of Northwest Fork. Ongoing restoration efforts seek to increase base flows into the

Northwest Fork, while not compromising the ecological integrity of downstream reaches (i.e.,

estuary) nor impairing valued ecosystem components of the estuary such as oysters and

seagrasses (SFWMD 2006).   
6

Figure 1.  Loxahatchee River watershed and associated features.

Materials and Methods

LRD scientists collected water quality samples monthly or every other month at the

stations identified in Table 1. At each station, physical water quality conditions (e.g.,

temperature, pH, conductivity, salinity, and dissolved oxygen) were evaluated using a multi‐

probe water quality instrument near the water surface (0.3 m depth). At stations 60 through

66, the river reach most likely to experience a halocline (salinity stratification), we also sampled

at mid‐depth and approximately 20 cm above the river bottom.   

Nutrient, bacteriological, chlorophyll a, turbidity, total suspended solids, and water

color samples were processed following Standard Methods by the Loxahatchee River District’s
7

WildPine Laboratory.  The WildPine Laboratory has been certified (#E56026) under the National

Environmental Laboratory Accreditation Program (NELAC) since 2000.    Prior to 2000, the

WildPine lab was a state certified laboratory. Analysis methods and detection limits are

summarized in Appendix C.    Photosynthetically active radiation (PAR) was assessed by

simultaneously logging at least three replicates of PAR using three LI‐COR spherical sensors (4

π) fixed at 20 cm, 50 cm, and 100 cm below the water surface.  Appendix E contains a complete

list of parameters for each station.

A key distinction in this report and analysis is the removal of problematic nitrogen data

(Total Kjeldahl Nitrogen (TKN), total nitrogen, organic nitrogen) collected prior to January 1,

2005.    Prior to 2005 the WildPine laboratory employed a laboratory analysis technique for

nitrogen that used mercury.    Unfortunately, we discovered that saline waters caused

interference in the results.    These problems were remedied in 2005 though the use of an

analysis technique utilizing copper. As a precaution to eliminate spurious results we removed

the nitrogen data for all samples collected prior to 2005 where salinity was greater than 10 ppt.  

While it is regrettable that these data are lost, it is fortunate that we identified and remedied

the analytical issue.

For consistency in analyses we summarized “annual” data collected from October 1

through September 30.    For example, the data group named “2010” included all data from

October 1, 2009 and September 30, 2010; the 5‐year target period group from 1998 – 2002

included all data collected from October 1, 1997 and September 30, 2002.

For our first data visualization tool we used a ‘stoplight’ approach to provide a

simplified, integrated assessment of annual observed water quality conditions for key nutrient

measures including Total Nitrogen, Total Phosphorus, and Chlorophyll a as measured by the

annual geometric mean. We compared the annual geometric mean relative to target water

quality values (1998‐2002) for each of the seven river reaches: marine, polyhaline, mesohaline,

wild and scenic, freshwater tributaries, brackish tributaries, and freshwater canals. We utilize

the geometric mean for consistency with DEP and EPA analytical approaches, and it is the more

appropriate measure of central tendency for skewed data. Analytical results for each river

reach were divided into three categories (red, yellow, and green), which can be interpreted
8

similar to the colors in a traffic signal. Appendix A presents the decision rules and data.  But in

general terms we evaluated the annual geometric mean relative to the 75th and 90th percentiles

from the data collected during the target period 1998‐2002.    Green indicates good or

acceptable conditions – no degradation is occurring. Yellow indicates caution should be

observed – degradation may or may not be occurring (i.e., there may be cause for concern).

Red indicates degradation likely is occurring, and resource managers should seek to identify the

source of the problem and determine what actions might be employed to remedy the observed

degradation in water quality.  

Next, we provide a more comprehensive and thorough temporal and spatial assessment

using box and whisker plots to compare water quality conditions for all parameters among the

following periods: the target period (1998‐2002), the subsequent 5 year period (2003‐2007),

and then annually 2008 through 2010.  

With the recent publication of the Environmental Protection Agency’s (EPA) Water

Quality Standards for the State of Florida’s Lakes and Flowing Waters, we provide an

assessment of the water quality at all freshwater sampling sites throughout the Loxahatchee

River watershed relative to EPA’s Numeric Nutrient Criteria instream protection values for

streams in Florida’s Peninsula region. To compliment the comparisons to the nutrient criteria,

we provide comparisons for the non‐freshwater segments to the 1998‐2002 target period using

the stoplight method described above. These comparisons provide a more detailed stoplight

assessment of annual water quality conditions for each sampling site for total nitrogen, total

phosphorus, chlorophyll a, dissolved oxygen, and fecal coliform bacteria.    Lastly, we present

maps showing all sampling sites symbolized by the 2010 stoplight scores developed from the

previously described comparisons to the numeric nutrient criteria, or the 1998‐2002 target

period.
9

Figure 2.  Loxahatchee River District’s water quality monitoring stations in the Loxahatchee

River and associated waters, color coded by river segment/analysis group.   
10

Table 1. RiverKeeper sampling sites. 

Station Analysis Group

Restoration Plan

Zone+

Sampling

Frequency Northing* Easting* Latitude** Longitude**

10 Marine Marine Monthly 950,408                957,903 26  56.7206 ‐80  04.4293

20 Marine Marine BM 953,238                956,193 26  57.1897 ‐80  04.7404

25 Marine BM 972,837                950,720 27  00.4308 ‐80  05.7224

30 Marine Marine BM 945,745                954,896 26  55.9546 ‐80  04.9892

32 Marine BM 948,686                955,606 26  56.4391 ‐80  04.8546

35 Brackish Trib BM 927,816                959,468 26  52.9901 ‐80  04.1717

40 Marine Monthly 951,108                951,709 26  56.8435 ‐80  05.5690

42 Polyhaline BM 952,109                946,497 26  57.0148 ‐80  06.5275

51 Polyhaline Polyhaline BM 954,927                948,122 26  57.4780 ‐80  06.2246

55 Brackish Trib BM 964,841                944,439 26  59.1185 ‐80  06.8901

59 FW Canal BM 989,168                933,755 27  03.1456 ‐80  08.8280

60 Polyhaline Polyhaline Monthly 954,920                942,739 26  57.4831 ‐80  07.2160

62 Meso/Oligohaline Meso/Oligohaline Monthly 961,525                938,899 26  58.5776 ‐80  07.9148

63 Meso/Oligohaline Meso/Oligohaline BM 965,503                934,848 26  59.2387 ‐80  08.6561

64 Meso/Oligohaline Meso/Oligohaline BM 966,884                934,503 26  59.4670 ‐80  08.7179

65 Meso/Oligohaline Monthly 966,873                931,330 26  59.4687 ‐80  09.3025

66 Wild & Scenic BM 964,747                929,142 26  59.1202 ‐80  09.7082

67 Wild & Scenic Wild & Scenic Monthly 961,353                928,662 26  58.5606 ‐80  09.8008

68 Wild & Scenic Wild & Scenic BM 953,689                928,384 26  57.2960 ‐80  09.8613

69 Wild & Scenic Wild & Scenic Monthly 947,259                924,583 26  56.2389 ‐80  10.5691

71 Brackish Trib BM 948,947                943,456 26  56.4965 ‐80  07.0916

72 Polyhaline Polyhaline Monthly 949,554                942,258 26  56.5981 ‐80  07.3114

73 Brackish Trib BM 948,621                942,812 26  56.4434 ‐80  07.2106

75 Brackish Trib BM 946,078                945,127 26  56.0211 ‐80  06.7876

81 FW Tributaries FW Tributaries BM 946,035                935,787 26  56.0246 ‐80  08.5075

86 FW Tributaries BM 942,562                930,899 26  55.4568 ‐80  09.4118

87 FW Tributaries BM 939,867                927,701 26  55.0155 ‐80  10.0039

88 FW Tributaries BM 949,254                927,103 26  56.5654 ‐80  10.1026

92 FW Canal BM 937,810                924,731 26  54.6793 ‐80  10.5531

95 FW Canal FW Tributaries Monthly 946,288                919,695 26  56.0839 ‐80  11.4703

100 FW Tributaries FW Tributaries Monthly 961,807                927,804 26  58.6365 ‐80  09.9583

101 FW Canal BM 978,724                927,740 27  01.4285 ‐80  09.9494

104 FW Canal BM 964,884                924,842 26  59.1475 ‐80  10.5002

105 FW Canal BM 959,657                920,431 26  58.2895 ‐80  11.3190

106 FW Tributaries BM 968,197                931,290 26  59.6873 ‐80  09.3082

107 Brackish Trib BM 962,186                934,199 26  58.6920 ‐80  08.7798

108 FW Tributaries BM 974,119                928,465 27  00.6677 ‐80  09.8215

111 FW Canal BM 983,296                927,764 27  02.1831 ‐80  09.9395

112 FW Canal BM 985,981                927,200 27  02.6268 ‐80  10.0401

Notes:

     +  From Restoration Plan, (SFWMD, 2006)

     ++  BM ‐ Bi‐Monthly (Every other month)

     * State Plane, Florida East, Ft

     ** WGS 1984, Degrees ‐ Decimal Minutes
11

Results & Discussion

During the period October 2009 through September 2010 we collected and analyzed

374 water quality samples for 29 parameters resulting in over 6,000 analytical results. Because

water quality is closely related to the hydrologic conditions in the region, we first provide an

assessment of rainfall and resulting river flows.   Water managers have established minimum

flow criteria that are designed to provide sufficient flows to protect the river’s freshwater

ecosystems from saltwater intrusion migrating up the river.

Rainfall and River Flows

Total annual rainfall for the period October 1 through September 30 was highest

observed since 2003.  The increased rainfall and effective flood control management resulted in

moderate but consistent river flows measured at Lainhart Dam.  In 2010 we recorded 70 inches

of rain at LRD’s treatment plant in Jupiter, compared to 60, 59, and 64 inches for the same

period (October‐September) in 2009, 2008 and 2007 (Table 2).  Annual average daily flows at

Lainhart Dam during the same period were also moderate at 89 cfs in 2010 compared to 77,

106, and 80 cfs for 2009, 2008 and 2007 (SFWMD‐DBHYDRO).  Daily flows over Lainhart Dam

were less than 35 cfs, the minimum target flow established in the Restoration Plan, for only 11

total days in 2010 compared to 45, 48, and 162 days during 2009, 2008 and 2007 (SFWMD‐

DBHYDRO). Figure 3 illustrates the daily rainfall and elevated flows in 2010, with fewer low‐flow

conditions compared to 2008 and 2009.    The increased rainfall during the 2009/2010 dry

season, and sound water management operations, resulted in the first time the Minimum

Flows and Levels (MFL) criteria were not violated in the Northwest Fork of the Loxahatchee

River since 1997.
12

Table 2. Summary of annual rainfall and river flows measured at Lainhart Dam.  Lainhart flow data from

SFWMD‐DBHYDRO.

Year

(Oct 1 – Sept 30)

Annual Average

Rainfall LRD

Treatment Plan (in.)

Annual Average

Daily Flow at

Lainhart Dam (cfs)

Number of days

where Lainhart

flow < 35 cfs

2010 70.0 89.1 11

2009 60.1 76.7 45

2008 59.4 105.8 48

2007 64.4 80.0 162

2006 56.7 89.4 143

2005 44.8 109.9 77

2004 63.9 79.3 143

2003 56.2 72.4 103
Figure 3. Plot of daily flow at Lainhart Dam and daily rainfall at LRD for the period of January 2008 throug

0

50

100150200250300350400

1/1/08

2/1/08

3/1/08

4/1/08

5/1/08

6/1/08

7/1/08

8/1/08

9/1/08

10/1/08

11/1/08

12/1/08

1/1/09

2/1/09

3/1/09

4/1/09

5/1/09

6/1/09

7/1/09

8/1/09

9/1/09

10/1/09

11/1/09

12/1/09

1/1/10

2/1/10

3/1/10

4/1/10

5/1/10

Daily Flow Lainhart Dam (cfs)
14

Stoplight Assessment

When compared against the water quality targets (i.e., non‐degradation standards),

water quality in the Loxahatchee River for 2010 (the period October 2009 through September

2010) scored “green/good” at all segments for total nitrogen and total phosphorus (Table 3).  

Two river segments (meso/oligohaline and brackish tributaries) showed elevated chlorophyll a

values and suggest possible impairment of these waters (i.e. ‘yellow’), relative to the 1998‐2002

target values. A cursory review of Chlorophyll a over time suggests a trend of increasing

concentrations relative to the 1998‐2002 target period.   However, more detailed analysis of

these data are needed to determine if these are definite trends, or artifacts due to changes in

sampling frequency (monthly prior to 2007 vs. bi‐monthly since 2007), variations in duration of

the reference period, or some other cause.  The marine and polyhaline segments continue to

show the greatest overall health. Semi‐diurnal tides flush these downstream sites twice a day

with relatively high quality (e.g., low nutrient concentrations) sea water flowing from the

Atlantic Ocean in through the Jupiter Inlet.  

In order to provide a historical perspective on water quality throughout the watershed,

we also provide the annual stoplight scores back to 2003 (Table 3).    Using these scoring

thresholds, the river appears relatively healthy.  Increased nutrient levels and the subsequent

‘yellow’ scores during the years labeled 2005 and 2006 (Oct. – Sept.) correspond with the heavy

tropical storm activity during that period.    Chlorophyll a values in the meso/oligohaline and

brackish tributary segments are more frequently higher than the target values than the other

segments. The temporal and spatial assessment sections (discussed below) provide additional

detail into these observations. These data are somewhat perplexing. The observed increase in

chlorophyll a appears to have occurred without an increase in either nitrogen or phosphorous.

It is conceivable that the observed increase in chlorophyll a is due to an increase in availability

of some other limiting nutrient. Presently, we do not have sufficient data to evaluate this

hypothesis.  

   
15

Table 3. A ‘stoplight’ assessment of water quality for Total Nitrogen, Total Phosphorus, and

Chlorophyll a among the seven reaches of the Loxahatchee River for each period October

through September relative to the target levels of 1998‐2002.    See Appendix A for decision

rules and data.

Total Nitrogen

Total Phosphorus

Chlorophyll a

Marine Polyhaline

Meso/Oligo

haline

Wild &

Scenic

FW

Tributaries

Brackish

Tributaries FW Canals

2003

2004

2005

2006

2007

2008

2009

2010

Marine Polyhaline

Meso/Oligo

haline

Wild &

Scenic

FW

Tributaries

Brackish

Tributaries FW Canals

2003

2004

2005

2006

2007

2008

2009

2010

Marine Polyhaline

Meso/Oligo

haline

Wild &

Scenic

FW

Tributaries

Brackish

Tributaries FW Canals

2003

2004

2005

2006

2007

2008

2009

2010
16

Temporal Assessment

In addition to the previous stoplight assessment, in Appendix B we present water quality

results using box and whisker plots for each parameter. These plots facilitate comparisons of

water quality for all parameters among five temporal periods: the target period (1998‐2002),

five years following the target period (2003‐2007), then 2008, 2009, and 2010 (October –

September for all). The following provides a brief summary of noteworthy results from 2010,

relative to the target period (1998‐2002) for each parameter.   

Alkalinity values measured in 2010 were above the target values in the polyhaline and

brackish tributary segments. Chlorophyll a values from 2010 in the oligo/mesohaline were

higher relative to the target period, but down from last year’s high.  Median chlorophyll values

in the brackish tributaries reached a new high, and are well above the target values.  

Conductivity and salinity values in 2010 were notably lower than the targets in the important,

saline sensitive meso/oligohaline and wild & scenic segments.  These lower salinities are likely a

result of the favorable river flows and higher annual rainfall during the dry season.   Median

dissolved oxygen values in 2010 in the wild & scenic segment were slightly lower than the

target period and similar to 2008.  In contrast, the median dissolved oxygen was higher than

historical observations in the freshwater canal segments.   Median fecal coliform values were

highest in the brackish tributaries, while all other segments were similar to previous

observations.    Percent light transmission readings in 2010 were higher than previous years,

meeting or exceeding median target periods nearly all river segments.    An important

observation is that despite heavier flows into the river, nitrogen related values (nitrate + nitrite,

TKN, total nitrogen, organic nitrogen, and ammonia) are generally similar to previous years, and

in‐line with target values. Note that comparisons of nitrogen related values (TKN, total

nitrogen, and organic nitrogen) in the marine segments, prior to 2005, are based on

substantially reduced sample sizes because of data removal (see methods section for details).  

Median pH values in 2010 were elevated relative to the target period in the marine, polyhaline

and brackish tributary segments.  Despite record cold water temperatures during January and

February 2010, the cooler temperatures are not reflected in the median or low range of the

RiverKeeper sampling relative to the target period.    This finding reinforces the benefits of
17

higher high frequency sampling using instrumentation because the timing of monthly or bi‐

monthly sample might not capture significant events. Similar to the 2010 nitrogen‐related

parameters, phosphorus values (orthophosphorus and total phosphorus) also did not show

substantial increases relative to the target period despite higher river flows and rainfall.  While

individual sites (see discussion below) show higher values, the combination of sites that

comprise an analysis segment appear to be relatively healthy and similar to the target period

values. Total suspended sediment and turbidity values in 2010 were lower in nearly all

segments relative to the target periods and previous observations.

Assessment of Individual Sampling Sites

In order to provide an increased level of detail, we evaluated annual water quality at

individual sampling sites throughout the watershed for five key parameters (total nitrogen,

total phosphorus, chlorophyll a, dissolved oxygen and fecal coliform bacteria). This analysis

provides additional insight into the water quality at specific sampling sites that comprise a river

segment analysis group described above.   We computed the annual geometric mean for the

five key parameters.    We compared the annual geometric mean of total nitrogen and total

phosphorus relative to EPA’s numeric nutrient criteria for freshwater streams in Florida for the

stations within the wild & scenic, freshwater tributaries and freshwater canal river segments.  

For the other segments (marine, polyhaline, meso/oligohaline, and brackish tributaries) we

compared the annual geometric mean to the 1998‐2002 target for the respective river

segment.  For the chlorophyll a we compared the station geometric mean relative to the 1998‐

2002 river segment targets. Observed dissolved oxygen concentrations were compared to

FDEP’s Class III surface water criteria.  Lastly, for the fecal coliform bacteria, we compared the

annual geometric mean relative to EPA and FDEP’s thresholds for recreational waters.

Total nitrogen values in 2010 were elevated (greater than 75% of the numeric nutrient

criteria limit) at the majority of sampling stations within Kitching Creek (Table 4 and figure in

Appendix C). Station 59, a canal tributary in the northern part of the watershed, exceeded the
18

numeric nutrient criteria value of 1.54 mg/l.    All other stations were below the 1998‐2002

target or the numeric nutrient criteria.   

Total phosphorus values were elevated at several sampling stations within the

meso/oligohaline and brackish tributary segments.  Two sampling sites (88 and 104) exceeded

the numeric nutrient criteria for phosphorus (Table 5 and Appendix C).   

Chlorophyll a values were elevated at more stations (17 total) than any other

parameter, and were distributed throughout the various river segments (Table 6 and Appendix

C).  Seven of the stations measured values greater than the 90th percentile of the target period

for the respective segment.  Clearly, chlorophyll a is a parameter that needs to be monitored

closely and further evaluated to gain a better understanding of the causes driving the increasing

concentrations.   

Observed dissolved oxygen values relative to FDEP’s Class III surface water criteria were

moderately low for fourteen stations and below the criteria at five stations (Table 7, Appendix

C).  We scored the annual geometric mean for each station ‘green/good’ for dissolved oxygen

values that exceeded the 5 mg/l criteria; ‘yellow/caution’ for values less than 5 mg/l, but

greater 3 mg/l, the lower limit for agricultural water supplies, and ‘red/poor’ for values less

than 3 mg/l.  All of the stations in the Wild & Scenic segment scored ‘yellow/caution’, but the

dissolved oxygen values are not surprising considering the connectivity between the river

channel and the floodplain swamp. Similarly low dissolved oxygen values in the

meso/oligohaline stations may be attributed to the significant groundwater inputs into this

segment of the river documented in studies by the U.S. Geological Survey.  While the dissolved

oxygen values for these segments are concerning relative to FDEP criteria, the values are

generally comparable to the 1998‐2002 targets using the previously described stoplight criteria.  

The freshwater canals, tributaries, and brackish tributaries each have stations that score

yellow/caution, or red and do not meet the state’s criteria for dissolved oxygen.  While these

stations have historically experienced low oxygen levels because of the nature of the sites (e.g.,

stagnant ditches, canals, etc.), they do not meet FDEP’s critera.

Fecal coliform bacteria counts were high at two stations (107 and 73), and moderately

high at two stations (106 and 75) (Table 8, Appendix C).    The Loxahatchee River District has
19

invested significant effort in converting existing development from the use of on‐site

wastewater treatment systems (i.e., septic systems) to the regional sanitary sewer.

Nonetheless, the homes surrounding station 107 continue to rely on septic systems for their

wastewater treatment.  

In Figure 4 we provide a synthesis of these data in a spatial plot.  When considering all

five parameters, station 88, a freshwater tributary/ditch that flows into the northwest fork,

station 75 at Jones Creek, a brackish tributary into the southwest fork, and station 107 a

brackish tributary into the northwest fork are the most degraded sampling sites in the

watershed.  Station 88 is a surface water outfall that delivers water from a fallow agriculture

area to the floodplain of the Northwest Fork just upstream of Masten Dam. During the dry

season this site (i.e., culvert) is dry. During the wet season low flows are observed as this site

following rainfall events.    Station 75 is in Jones Creek, a drainage tributary for an extensive

urban area of Jupiter.    The Town of Jupiter, in partnership with the Loxahatchee River

Preservation Initiative (LRPI), continues work a variety of stormwater improvement projects

that may improve water quality within this sub‐basin.    Station 107 is in a tributary of the

Northwest Fork referred to as Ketter Creek. This tributary provides drainage to an older

residential community that relies on septic systems for wastewater treatment as well as a new

development on former agriculture fields.    These three sampling sites clearly present

opportunities for restoration that would further improve surface water quality within the

Loxahatchee River watershed.
20

Table 4. Summary of annual geometric mean for total nitrogen by sample station, color coded by

numeric nutrient criteria for Florida streams, or 1998‐2002 target values, Loxahatchee River, Florida.

Total Nitrogen (mg/l)

Freshwater Segments Color Coded by EPA's Numeric Nutrient Criteria for Florida Streams

River Analysis Zone Site 1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

Wild & Scenic 66 1.07 1.27 0.98 1.33 1.49 1.09 0.88 0.98 0.74

67 0.93 1.07 1.00 1.22 1.34 1.10 0.97 1.05 0.85

68 0.97 1.01 1.03 1.38 1.37 1.37 0.96 1.02 0.91

69 0.88 1.09 0.97 1.37 1.30 1.11 0.99 1.05 0.93

FW Tributaries 81 0.90 1.02 0.96 1.34 1.18 1.29 0.91 1.10 0.87

86 0.64 1.06 0.89

87 0.62 1.11 0.87

88 1.30 1.45 1.17

100 1.07 1.14 0.95 1.45 1.32 1.09 0.98 1.02 0.89

106 1.18 1.44 0.98 1.48 1.91 1.09 1.15 1.04 1.24

108 2.14 1.34 0.94 1.34 1.22

FW Canal 59 1.20 1.05 1.47 1.60 2.05 1.95 1.42 2.24 1.89

92 0.97 0.92 0.98 1.44 1.32 1.37 1.01 1.18 0.90

95 0.85 0.95 0.87 1.52 1.27 1.48 0.88 1.10 0.93

101 1.23 1.38 1.11 1.95 2.10 2.02 1.19 1.62 1.52

104 1.37 1.77 1.26 1.93 1.42 1.14 0.99 1.13 1.08

105 1.11 1.14 0.97 1.51 1.52 1.09 0.88 1.02 1.05

111 1.23 1.15 1.54 1.86 1.65 0.87 1.79 1.50

112 1.23 1.65 1.42 2.08 1.81 1.38 1.38 1.41

* Color Code ‐ Yellow: >1.16 (75% of NNC Limit) and <1.54 (NNC Limit); Red: >1.54 (NNC Limit)

Color Coded By Loxahatchee River District Targets from 1998 ‐ 2002

River Analysis Zone Site 1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

Marine 10 0.85 0.60 0.45 0.15 0.16 0.12 0.16

20 0.78 0.59 0.28 0.17 0.18 0.16 0.15

25 0.82 0.73 0.37 0.12 0.12 0.16 0.11

30 0.95 0.68 0.47 0.18 0.22 0.18 0.21

32 0.67 0.54 0.17 0.17 0.12 0.19

40 1.44 0.63 0.69 0.38 0.20 0.19 0.11 0.11

* Thresholds not available because of limited data (see methods)

Brackish Trib 35 1.17 0.65 0.42 0.22 0.33 0.18 0.16

55 1.26 1.46 1.75 1.41 0.65 0.75 0.37 0.47 0.45

71 1.23 2.40 1.24 1.14 0.63 0.39 0.56 0.27 0.38

73 1.28 2.47 0.81 0.79 0.71 0.65 0.66 0.49 0.58

75 0.49 0.62 0.58 0.82

107 1.20 1.62 1.20 2.26 1.81 0.60 1.01 0.99 0.91

* Color Code ‐ Yellow (>1.46 and <1.79); Red >1.79

Polyhaline 42 1.62 0.78 0.57 0.37 0.36 0.18 0.25

51 0.54 1.86 0.78 0.50 0.30 0.30 0.23 0.15

60 1.77 1.06 2.09 1.25 0.76 0.35 0.55 0.54 0.30

72 1.41 2.49 0.86 1.22 0.78 0.55 0.56 0.40 0.49

* Color Code ‐ Yellow (>1.95 and <2.32); Red >2.32

Meso/Oligohaline 62 1.46 1.78 2.18 2.73 0.97 0.62 0.77 0.58 0.72

63 1.33 1.83 1.15 2.01 1.49 0.52 1.29 0.77 0.91

64 1.26 2.16 1.07 1.86 1.69 0.69 1.18 0.84 0.87

65 1.13 1.68 0.99 1.43 1.64 0.98 0.93 0.94 0.89

* Color Code ‐ Yellow (>1.54 and <1.91); Red >1.91
21

Table 5. Summary of annual geometric mean for total phosphorus by sample station, color coded by

numeric nutrient criteria for Florida streams, or 1998‐2002 target values, Loxahatchee River, Florida.

Total Phosphorus (mg/l)

Freshwater Segments Color Coded by EPA's Numeric Nutrient Criteria for Florida Streams

River Analysis Zone Site 1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

Wild & Scenic 66 0.055 0.058 0.061 0.059 0.062 0.072 0.051 0.061 0.056

67 0.043 0.046 0.048 0.045 0.049 0.080 0.060 0.051 0.044

68 0.040 0.042 0.040 0.036 0.042 0.080 0.046 0.053 0.047

69 0.033 0.032 0.030 0.033 0.032 0.054 0.043 0.041 0.038

FW Tributaries 81 0.028 0.037 0.016 0.025 0.026 0.029 0.026 0.024 0.027

86 0.027 0.040 0.027

87 0.038 0.028 0.034

88 0.350 0.587 0.492

100 0.059 0.058 0.045 0.065 0.060 0.070 0.058 0.058 0.065

106 0.068 0.077 0.081 0.052 0.088 0.081 0.086 0.085 0.069

108 0.105 0.087 0.063 0.089 0.068

FW Canal 59 0.060 0.040 0.076 0.054 0.101 0.070 0.080 0.223 0.076

92 0.031 0.031 0.027 0.031 0.033 0.057 0.039 0.040 0.040

95 0.038 0.042 0.043 0.050 0.041 0.088 0.074 0.069 0.057

101 0.067 0.058 0.038 0.064 0.090 0.086 0.051 0.078 0.068

104 0.085 0.094 0.095 0.105 0.121 0.080 0.107 0.108 0.144

105 0.058 0.061 0.059 0.057 0.075 0.085 0.035 0.055 0.064

111 0.053 0.041 0.033 0.052 0.054 0.036 0.102 0.055

112 0.031 0.057 0.021 0.067 0.037 0.050 0.067 0.040

* Color Code ‐ Yellow: >0.09 (75% of NNC Limit) and <0.12 (NNC Limit); Red: >0.12 (NNC Limit)

Color Coded By Loxahatchee River District Targets from 1998 ‐ 2002

River Analysis Zone Site 1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

Marine 10 0.017 0.012 0.012 0.043 0.013 0.009 0.016 0.014 0.014

20 0.013 0.008 0.010 0.034 0.010 0.004 0.008 0.011 0.008

25 0.019 0.014 0.012 0.022 0.022 0.013 0.015 0.013 0.012

30 0.030 0.022 0.027 0.031 0.033 0.024 0.021 0.022 0.027

32 0.029 0.029 0.019 0.020 0.022 0.023

40 0.022 0.015 0.013 0.031 0.023 0.008 0.019 0.013 0.015

* Color Code ‐ Yellow (>0.033 and <0.043); Red >0.043

Brackish Trib 35 0.034 0.029 0.029 0.032 0.030 0.022 0.026 0.024 0.023

55 0.042 0.037 0.049 0.042 0.045 0.043 0.039 0.040 0.040

71 0.048 0.041 0.052 0.044 0.047 0.031 0.046 0.034 0.044

73 0.055 0.049 0.066 0.052 0.049 0.040 0.065 0.048 0.047

75 0.067 0.079 0.074 0.088

107 0.208 0.179 0.232 0.115 0.091 0.107 0.101 0.110 0.118

* Color Code ‐ Yellow (>0.080 and <0.150); Red >0.150

Meso/Oligohaline 62 0.049 0.045 0.062 0.050 0.051 0.056 0.057 0.048 0.052

63 0.054 0.055 0.062 0.059 0.059 0.062 0.064 0.058 0.069

64 0.053 0.062 0.065 0.057 0.065 0.064 0.064 0.062 0.066

65 0.056 0.064 0.066 0.055 0.068 0.072 0.063 0.061 0.066

* Color Code ‐ Yellow (>0.066 and <0.081); Red >0.081

Polyhaline 42 0.031 0.028 0.025 0.021 0.024 0.018 0.026

51 0.027 0.020 0.026 0.030 0.028 0.016 0.023 0.023 0.024

60 0.037 0.030 0.035 0.038 0.041 0.056 0.038 0.031 0.037

72 0.041 0.032 0.042 0.043 0.037 0.031 0.038 0.030 0.035

* Color Code ‐ Yellow (>0.044 and <0.070); Red >0.070
22

Table 6. Summary of annual geometric mean for chlorophyll a by sample station, color coded by 1998‐

2002 target values, Loxahatchee River, Florida.

Clorophyll a

Color Coded By Loxahatchee River District Targets from 1998 ‐ 2002

Zone Site 1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

10 1.9 2.3 2.3 3.3 0.9 1.0 2.4 1.6 2.0

20 1.5 1.8 1.9 2.9 0.9 0.5 3.4 1.2 1.1

25 2.8 4.0 3.4 4.7 2.5 1.7 3.7 1.8 2.2

30 4.4 6.0 8.9 6.3 4.6 5.4 8.4 5.6 7.9

32 4.7 4.3 4.9 7.3 5.5 5.7

40 2.6 3.5 2.7 4.1 2.0 2.2 3.9 2.4 2.6

* Color Code ‐ Yellow (>4.2 and <6.9); Red >6.9

42 4.5 7.2 3.0 5.6 6.8 4.4 7.1

51 3.7 5.6 10.3 7.7 3.2 4.2 6.0 5.0 5.4

60 4.2 6.8 4.0 10.6 5.8 4.9 7.4 8.4 7.3

72 9.9 15.7 13.4 17.0 6.5 13.3 12.8 11.7 14.8

* Color Code ‐ Yellow (>9.3 and <14.5); Red >14.5

62 4.1 6.9 6.2 7.6 6.9 5.6 8.8 9.4 8.1

63 4.2 8.8 4.6 7.6 5.3 5.6 8.9 8.7 7.9

64 4.0 10.3 3.8 7.6 4.0 3.2 8.1 7.0 8.5

65 3.7 7.5 4.5 5.3 3.1 4.7 5.6 8.5 5.6

* Color Code ‐ Yellow (>5.8 and <8.3); Red >8.3

66 3.5 3.8 3.6 4.6 3.0 4.1 1.9 5.4 3.2

67 2.2 1.2 1.3 4.0 1.6 3.7 3.5 3.8 2.3

68 1.8 1.3 1.1 3.2 1.5 2.8 4.1 3.2 3.0

69 2.6 3.7 2.8 5.2 2.1 5.7 7.1 9.6 8.6

* Color Code ‐ Yellow (>4.4 and <8.3); Red >8.3

81 5.0 10.5 3.8 6.4 2.4 12.5 6.9 7.0 9.0

86 10.0 12.4 12.2

87 11.2 10.3 12.6

88 49.5 48.2 19.5

100 2.8 3.2 2.3 3.7 1.4 4.0 2.7 3.1 2.9

106 4.4 6.7 9.9 4.0 5.2 4.0 10.4 7.3 5.5

108 5.2 3.3 7.5 4.6 3.5

* Color Code ‐ Yellow (>8.0 and <12.8); Red >12.8

35 3.4 3.8 7.5 8.0 4.5 5.5 8.5 6.0 7.9

55 5.6 8.4 4.6 13.8 5.0 11.2 5.3 10.1 8.7

71 7.3 9.6 9.9 16.2 6.2 10.5 12.3 11.3 12.6

73 8.4 16.9 14.2 22.0 5.8 11.1 17.8 12.6 15.2

75 16.0 11.6 20.1

107 3.6 5.4 4.4 14.4 5.7 5.0 4.0 4.0 7.0

* Color Code ‐ Yellow (>8.9 and <13.7); Red >13.7

59 6.3 13.3 2.5 6.0 15.7 6.8 10.1 14.5 11.9

92 4.5 10.1 3.6 8.4 3.4 9.1 7.3 10.9 11.0

95 3.1 4.5 3.8 6.4 2.0 10.0 8.4 11.0 7.8

101 10.6 27.3 10.8 13.5 8.3 13.9 7.1 9.8 21.6

104 11.3 11.7 9.7 21.1 7.7 3.4 17.3 20.0 12.8

105 3.5 3.6 2.4 4.5 2.3 1.2 2.7 4.0 4.4

111 19.1 9.0 7.1 5.2 9.4 7.3 12.1 9.6

112 16.2 12.3 6.6 8.5 7.0 9.8 7.0 5.5

* Color Code ‐ Yellow (>11.0 and <26.5); Red >26.5

FW Tributaries Brackish Trib FW Canal Marine Polyhaline Meso/Oligo haline Wild

&

Scenic
23

Table 7. Summary of annual geometric mean for dissolved oxygen by sample station, color coded by

FDEP’s criteria for surface waters of the State of Florida, Loxahatchee River, Florida.

Dissolved Oxygen (mg/l)

Color Coded By FDEP Criteria for Class III Florida Waters

Zone Site 1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

10 6.49 6.33 6.13 6.64 6.32 6.62 6.51 6.72 6.96

20 6.66 6.63 6.41 6.61 6.18 6.56 6.64 6.79 7.06

25 6.62 6.33 6.07 6.44 6.32 6.24 6.41 6.59 6.59

30 6.00 5.96 5.80 6.44 5.41 5.88 5.96 6.06 6.22

32 6.14 5.34 5.89 5.93 5.94 6.20

40 6.65 6.53 6.36 6.62 6.45 6.65 6.54 6.85 7.09

42 6.50 6.51 6.08 6.04 5.86 6.27 6.62

51 6.25 5.91 5.80 6.27 6.16 5.92 6.35 6.28 6.85

60 6.20 5.86 6.27 6.34 5.78 5.61 6.04 6.22 6.28

72 6.16 5.31 5.48 6.31 6.06 5.22 5.95 5.93 5.30

62 5.40 5.12 4.86 5.71 5.04 4.61 5.26 5.48 5.57

63 5.14 4.73 3.56 5.23 4.23 4.10 4.65 4.60 4.64

64 5.22 4.75 3.21 5.17 4.11 4.46 4.92 4.54 4.82

65 4.99 3.81 2.91 5.60 3.15 3.50 5.00 3.46 4.75

66 5.63 5.46 4.88 6.05 4.39 4.27 4.97 4.86 4.85

67 5.67 5.40 4.55 4.91 3.93 4.10 4.57 4.61 4.95

68 5.75 5.64 6.67 4.70 4.45 4.17 4.52 4.78 4.87

69 4.41 4.08 5.00 3.99 4.05 3.25 4.02 4.19 3.81

81 6.73 6.42 6.00 5.40 6.09 5.49 5.46 6.79 5.88

86 6.44 6.58 6.37

87 6.90 6.18 6.24

88 1.16 0.69 1.60

100 6.17 6.24 5.91 6.15 4.88 5.23 5.71 5.39 5.17

106 3.68 3.53 4.66 3.98 4.59 4.30 4.03 3.52 4.27

108 3.92 2.75 3.21 3.83 4.82

35 5.61 5.50 5.81 6.03 5.82 5.72 5.70 6.01 5.93

55 4.94 3.51 3.67 5.30 4.22 4.27 4.22 4.22 4.98

71 5.28 4.64 4.18 5.76 5.59 5.70 4.68 5.52 5.69

73 4.86 4.30 3.75 5.36 4.99 5.50 4.40 4.95 5.94

75 3.01 2.91 2.72 2.95

107 4.40 2.90 5.07 4.37 4.00 3.99 4.58 4.12 3.40

59 0.50 0.53 0.49 1.35 1.79 0.88 0.36 0.36 2.77

92 5.26 4.55 5.16 4.21 4.52 2.80 4.60 4.38 4.37

95 5.30 4.73 4.29 4.39 4.73 3.32 4.15 4.59 4.51

101 0.74 0.58 1.77 2.28 2.12 1.01 1.09 2.36 2.67

104 6.33 4.77 6.72 5.96 5.54 4.84 5.29 6.45 6.49

105 4.69 3.12 5.68 4.91 4.91 3.40 3.83 4.00 5.42

111 2.18 1.86 1.78 1.33 1.39 1.19 1.43 2.81

112 0.81 1.32 3.08 2.31 2.81 1.18 3.14 4.05

* Color Code ‐ Yellow (> 3.0 and < 5.0); Red < 3.0 FW Canal Marine Polyhaline Meso/Oligo haline Wild

&

Scenic

FW Tributaries Brackish Trib
24

Table 8. Summary of annual geometric mean for fecal coliform bacteria by sample station, color coded

by EPA and FDEP’s criteria for recreational waters.

Fecal Coliform (cfu 100/ml)

Color Coded By EPA and FDEP Criteria for Recreational Waters

Zone Site 1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

10 4 1 5 5 5 2 8 2 2

20 3 6 5 8 3 2 2 1 1

25 3 3 2 6 2 2 2 1 1

30 13 17 15 10 12 6 19 7 8

32 41 13 15 43 17 19

40 5 6 6 10 10 3 11 1 3

42 61 10 36 9 49 8 30

51 12 6 11 14 17 8 33 5 9

60 40 20 30 18 15 17 53 14 31

72 53 59 57 145 52 97 197 67 121

62 73 66 40 142 46 61 149 51 90

63 117 115 188 120 115 76 276 63 127

64 129 132 121 102 92 91 187 79 156

65 164 131 235 145 88 118 217 160 166

66 174 149 214 91 97 193 103 144 109

67 154 168 191 52 54 136 114 109 91

68 209 152 167 94 62 147 141 42 72

69 36 36 53 38 50 44 75 26 44

81 87 137 152 90 94 134 143 76 38

86 30 21 19

87 23 8 7

88 80 67 45

100 148 80 105 132 47 119 93 90 59

106 193 185 323 129 173 312 193 357 245

108 261 189 134 240 64

35 41 14 13 19 14 8 14 9 9

55 135 137 130 139 57 115 303 92 123

71 84 68 139 125 136 50 158 97 150

73 145 202 346 513 194 254 922 441 520

75 110 327 214 331

107 544 1262 1207 745 633 295 815 919 455

59 42 104 115 49 49 170 53 105 22

92 29 25 35 40 72 86 28 31 31

95 112 81 112 211 326 107 270 81 196

101 27 15 90 26 35 240 57 42 113

104 131 215 179 106 87 86 84 40 90

105 44 35 31 96 26 54 39 20 26

111 43 88 38 37 49 77 158 27

112 66 406 59 58 94 66 80 55

* Color Code ‐ Yellow (>200 and <400); Red >400 based on FDEP and EPA thresholds for recreational waters FW Canal Marine Polyhaline Meso/Oligo haline Wild

&

Scenic

FW Tributaries Brackish Trib
25

   

Figure 4.  Synthesis of 2010 water quality stoplight scoring by sampling site for total phosphorus (TP), total

nitrogen (TN), chlorophyll a (CLA), dissolved oxygen (DO), and fecal coliform (FC), Loxahatchee River, Florida. Bar

height corresponds to stoplight score relative to reference period or numeric nutrient critera. No bar is equivalent

to green/good, short bar equivalent to yellow/concern; and tall bar equivalent to red/poor.  See text for details on

scoring.
26

Conclusions

In conclusion, water quality in the Loxahatchee River during 2010 was generally good.  

These findings are encouraging because the river experienced greater base flows than observed

over the past several years.  In fact, during the 2009/2010 dry season, river flows measured at

Lainhart Dam fell below the 35 cfs target for only 11 days total, and it was the first year since

1997 that the MFL was not violated.    Higher than usual rainfall, particularly during the dry

season, and improved water management within the basin were key contributors to improved

flows.

Despite the increased flows, total nitrogen and phosphorus values were generally below

target values established by EPA’s numeric nutrient criteria, and the 1998‐2002 targets

established by LRD. Elevated chlorophyll a concentrations, particularly in the meso/oligohaline

and brackish water tributaries continue to present values higher than the 1998‐2002 targets.  

Further investigation into the causes and potential consequences of the elevated chlorophyll a

concentrations is needed.

This report provides a historical assessment of water quality for five key parameters by

river segment and by individual sampling station, relative to EPA’s numeric nutrient criteria and

the 1998‐2002 targets.    Fortunately, the vast majority of sampling sites in the Loxahatchee

River watershed meet the numeric nutrient criteria for nitrogen and phosphorus.  In general,

many of the parameters with elevated concentrations correspond with significant weather

events observed in 2004 and 2005.    Elevated chlorophyll a and low dissolved oxygen levels

were observed at a variety of sampling sites throughout the watershed.  We cannot identify a

straightforward explanation for the elevated chlorophyll values.  While there are some logical

explanations for the lower dissolved oxygen observations, the water quality does not

consistently meet FDEP’s criteria for Class III waters.   Three sampling sites present consistently

poor water quality and these sub‐basins should be targeted for restoration work to improve

water quality.   

We believe the RiverKeeper water quality monitoring project continues to be an

excellent and efficient approach to monitor water quality in the Loxahatchee River watershed.

Because of LRD’s long standing commitment to assess water quality in the Loxahatchee River
27

watershed, we have an excellent historical record against which present water quality

conditions can be compared. As restoration efforts continue to move forward in the watershed,

we will continue to assess current water quality conditions and compare them against EPA’s

numeric nutrient criteria, established target conditions (1998‐2002) and the pre‐restoration

conditions, thereby providing a comprehensive measure of project success. Such across‐time

comparisons are invaluable when trying to adaptively manage our valuable resources. Finally, it

should be noted that while much work has been done in the Loxahatchee River Watershed

(e.g., the numerous LRPI projects) there continue to be water quality issues that need to be

addressed.   

Recommendations for future work:

1. Continue the RiverKeeper monitoring project to assess long‐  and short‐term

trends in water quality in the Loxahatchee River.  These data provide essential

information for adaptive management of restoration activities.

2. Further assess causes and potential consequences of elevated chlorophyll a

concentrations observed at various sites throughout the watershed.

3. Where water quality concerns are identified, resource managers should identify

the source of the degradation, and develop and implement projects to remedy

the source of water quality degradation.

4. The RiverKeeper data should be used to the greatest extent possible by the

Department of Environmental Protection under their efforts to assess Total

Maximum Daily Loads (TMDL) for the Loxahatchee River and tributaries.  
28

Literature Cited

Comprehensive Everglades Restoration Plan (CERP). 2001. Baseline Report for the

Comprehensive Everglades Restoration Plan. South Florida Water Management District,

West Palm Beach, Florida.  

ESRI.  2009.  ArcGIS Desktop Resource Help.  

South Florida Water Management District (SFWMD). 2006. Restoration Plan for the Northwest

Fork of the Loxahatchee River. South Florida Water Management District, West Palm Beach,

Florida.   

South Florida Water Management District (SFWMD)  ‐  DBHYDRO. 2010. South Florida Water

Management District's hydrometeorologic, water quality, and hydrogeologic data retrieval

system at www.sfwmd.gov. South Florida Water Management District, West Palm Beach,

Florida.   
29

Appendix A ‐ Stoplight Decision Rules & Data. Decision rules and data used in the ‘stoplight’

assessment. Because we assumed the observed conditions during the target period (1998‐2002)

represent non‐degradation conditions, we therefore scored conditions equal to or better than those

conditions as green (good). Conditions marginally worse than the target conditions (i.e., between the

75th and 90th percentile) were scored yellow (caution). Observed conditions significantly worse than the

target conditions (i.e., falling above of the 90th percentile) were scored as red (cause for concern).  

Scoring criteria is generally based on FDEP’s proposed approach for Numeric Nutrient Criteria

Development in Marine Waters. Assessment is based on the annual geometric mean (GM) value (utilized

by EPA and FDEP) for the parameter and period being assessed. Total nitrogen values prior to 2005 have

smaller sample sizes to due to data removal because of interference in analysis method.  See methods

section for additional information.  

< 75th Percentile

Target Value

> 75th Percentile and

< 90th Percentile

Target Value

>90th Percentile

Target Value

   

Total Nitrogen (mg/l)

1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

N 1 5 0 30 30 44 48 48 48

GM 1.44 0.80 0.66 0.41 0.16 0.17 0.13 0.15

75th N/A

90th N/A

N 8 3 3 20 22 32 36 36 36

GM 1.40 1.70 1.43 0.98 0.65 0.40 0.47 0.35 0.30

75th 1.95

90th 2.32

N 84 20 18 23 24 32 35 36 36

GM 1.26 1.87 1.15 1.92 1.42 0.70 0.96 0.76 0.83

75th 1.54

90th 1.91

N 120 24 24 24 24 32 36 36 36

GM 0.96 1.10 0.99 1.32 1.38 1.15 0.96 1.03 0.87

75th 1.26

90th 1.56

N 87 17 18 18 23 28 43 44 47

GM 1.04 1.17 0.96 1.42 1.57 1.18 0.89 1.11 0.99

75th 1.29

90th 1.69

N 28 11 9 26 29 31 36 36 37

GM 1.22 1.66 1.26 1.16 0.75 0.48 0.55 0.43 0.49

75th 1.46

90th 1.79

N 179 48 44 47 46 45 50 49 57

GM 1.11 1.18 1.15 1.61 1.66 1.47 1.03 1.31 1.14

75th 1.37

90th 1.77

FW Canals Marine Polyhaline Meso/Oligo haline Wild

&

Scenic

FW

Tributaries

Brackish

Tributaries
30

Appendix A continued

Total Phosphorus (mg/l)

   

1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

N 149 30 30 35 36 44 48 48 48

GM 0.019 0.014 0.014 0.031 0.020 0.010 0.016 0.015 0.015

75th 0.033

90th 0.043

N 90 18 21 24 24 32 36 36 36

GM 0.035 0.027 0.033 0.034 0.032 0.030 0.032 0.027 0.032

75th 0.044

90th 0.070

N 119 24 24 24 24 32 36 36 36

GM 0.053 0.056 0.064 0.055 0.060 0.063 0.061 0.056 0.061

75th 0.066

90th 0.081

N 120 24 24 24 24 32 36 36 36

GM 0.042 0.044 0.043 0.042 0.045 0.069 0.050 0.049 0.044

75th 0.056

90th 0.089

N 89 18 18 18 23 28 43 44 47

GM 0.048 0.055 0.039 0.044 0.060 0.063 0.053 0.055 0.060

75th 0.079

90th 0.101

N 148 30 30 30 30 31 36 36 37

GM 0.059 0.052 0.065 0.051 0.049 0.042 0.054 0.048 0.053

75th 0.080

90th 0.150

N 179 48 45 47 46 45 50 49 57

GM 0.053 0.048 0.051 0.047 0.067 0.069 0.057 0.076 0.058

75th 0.085

90th 0.134

FW Canals Marine Polyhaline Meso/Oligo haline Wild

&

Scenic

FW

Tributaries

Brackish

Tributaries
31

Appendix A continued

Chlorophyll a (μg/l)

1998‐2002 2003 2004 2005 2006 2007 2008 2009 2010

N 146 29 30 35 36 38 48 48 48

GM 2.5 3.3 3.3 4.2 2.0 1.8 4.0 2.4 2.7

75th 4.2

90th 6.9

N 89 17 21 22 24 28 35 36 36

GM 5.4 8.5 7.5 9.9 4.3 6.7 8.5 7.7 8.8

75th 9.3

90th 14.5

N 120 24 24 24 24 28 32 36 36

GM 4.0 8.3 4.7 6.9 4.6 4.8 7.5 8.5 7.2

75th 5.8

90th 8.3

N 120 24 24 24 24 28 34 36 36

GM 2.4 2.2 1.9 4.2 2.0 4.1 4.2 5.3 3.9

75th 4.4

90th 8.3

N 88 18 18 18 23 24 40 44 47

GM 3.9 6.0 4.4 4.6 3.0 4.9 7.4 6.6 6.6

75th 8.0

90th 12.8

N 148 30 30 27 29 25 36 36 37

GM 5.4 7.7 7.3 13.8 5.4 8.2 9.2 8.5 11.0

75th 8.9

90th 13.7

N 176 47 45 47 46 36 46 49 57

GM 5.8 11.3 5.5 8.1 5.3 5.9 7.9 10.2 9.3

75th 11.0

90th 26.5

FW Canals Marine Polyhaline Meso/Oligo haline Wild

&

Scenic

FW

Tributaries

Brackish

Tributaries
32

Appendix B – Box & Whisker Plots. Box and whisker plots of Loxahatchee River District’s

RiverKeeper data for the period October 1997 through September 2010.  See Figure 2 for a map

of sample site locations.  In these box plots, the center horizontal line marks the median of the

sample. The length of each box shows the range within which the central 50% of the values fall,

with the box edges at the first and third quartiles. The whiskers show the range of observed

values that fall within inner fences (1.5*interquartile range). Because the whiskers extend to

observed values and the fences need not correspond to observed values, the whiskers do not

necessarily extend all the way to the inner fences. Values between the inner and outer fences

(3*interquartile range) are plotted with asterisks. Values beyond the outer fences, called far

outside values, are plotted with empty circles (SYSTAT, 2009).

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0

100

200

300

400

Alkalinity (mg/l)
33

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

1

10

100

Log Chlorophyll a (ug/l)

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0

100

200

300

400

500

Color (PCU)
34

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

100

1000

10000

Log Conductivity (umho/cm)

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0

5

10

15

Dissolved Oxygen (mg/l)
35

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

1

10

100

1000

10000

Log Fecal Coliform (cfu/100ml)

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0

10

20

30

40

50

60

70

80

90

100

Percent Light (at 1m)
36

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0.1

1.0

Log Ammonia (mg-N/l)

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0.01

0.10

Log Nitrate + Nitrite (mg-N/l)
37

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0.001

0.010

0.100

1.000

Log Orthophosphorus (mg-P/l)

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

5

6

7

8

9

pH
38

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0

10

20

30

40

Salinity (ppt)

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

10

20

30

40

Temperature (C)
39

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0.1

1.0

10.0

Log Total Kjehldahl Nitrogen (mg-N/l)

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0.1

1.0

10.0

Log Total Nitrogen (mg-N/l)
40

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0.001

0.010

0.100

1.000

Log Total Phosphorus (mg-P/l)

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

1

10

100

Log Total Suspended Solids (mg/l)
41

   

2010

2009

2008

2003-2007

1998-2002

Analysis Period

Marine

Polyhaline

Meso/Oligohaline

Wild & Scenic

FW Tributaries

Brackish Tributaries

FW Canals

0

10

20

30

40

50

60

70

Turbidity (NTU)
42

Appendix C – Spatial Plots. Spatial plots of select water quality parameters from the

Loxahatchee River District’s RiverKeeper data for the period October 2009 through September

2010.   
43

   
44

   
45

   
46
47

Appendix D – Analysis Methods & Calibration Criteria LOXAHATCHEE RIVER DISTRICT WILDPINE LAB E56026

TABLE OF CALIBRATION ACCEPTANCE CRITERIA FOR LAB ACTIVITIES

Effective Date: 4/24/03 Rev. 8 on January 2010

 [HISTORICAL VALUES]

PARAMETER/ BLANK LOQ # OF INITIAL CALIB 2ND CONTINUING PRECISION ACCURACY HOLD

METHOD (mg/L) (mg/L) INITIAL CORR COEF STD CALIB (LCS) OF DUPS OF SPIKES TIMES/

STDS OR % R % R % R % RPD % R PRES

Fecal Coliform 1 pre-1 post + 1 cfu/ N/A N/A N/A N/A [0 - 50] N/A 6 hours

SM9222D every 10 sampl 100 mLs every 10 samples on ice

MF less than LOQ or matrix set

Total Coliform 1 pre-1 post + 1 cfu/ N/A N/A N/A N/A [0 - 50] N/A 6 hours

SM9222B every 10 sampl 100 mLs every 10 samples on ice

MF less than LOQ or matrix set

Ammonia-N low 1 pre- + 0.05 6 to >/= 0.995 90 - 110 80 - 120 [0 - 30] [80 - 120] 28 days

SM4500-NH3 C (18th ed) every 10 samples bracket one prior LCS in dup everyevery 10 sampleesvery 10 samples w /H2SO4

Color, Nessler's less than LOQ samples to sample analysis10 samples + end or matrix set or matrix set

Ammonia-N high 1 pre- + 0.2 3 to >/= 0.995 90 - 110 80 - 120 [0 - 10] [85-115] 28 days

SM4500-NH3 C every10 samples bracket one prior LCS in dup everyevery 10 sampleesvery 10 samples w /H2SO4

Titrimetric less than LOQ samples to sample analysis10 samples + end or matrix set or matrix set

TKN 1 pre- + 0.2 6 to >/= 0.995 90 - 110 90 - 110 [0 - 20] 90 - 110 28 days

EPA 351.2 every 10 samples bracket one prior LCS in dup everyevery 10 sampleesvery 10 samples w /H2SO4

Block, FIA less than LOQ samples to sample analysis10 samples + end or matrix set or matrix set

Nitrate+Nitrate-N low 1 pre- + 0.005 6 to >/= 0.995 90 - 110 90 -110 [0 - 20] 90 -110 48 hours

EPA 353.2 every 10 samples bracket one prior LCS in dup everyevery 10 sampleesvery 10 samples no acid

Cd Reduc, FIA less than LOQ samples to sample analysis10 samples + end or matrix set or matrix set filter

Nitrate+Nitrate-N high 1 pre- + 0.02 6 to >/= 0.995 90 - 110 90 -110 [0 - 14] 90 -110 28 days

EPA 353.2 every 10 samples bracket one prior LCS in dup everyevery 10 sampleesvery 10 samples w /H2SO4

Cd Reduc, FIA less than LOQ samples to sample analysis10 samples + end or matrix set or matrix set filter

Ortho-Phosphate 1 pre- + 0.003 6 to >/= 0.995 90 - 110 80 -120 [0 - 20] [90 - 110] 48 hours

SM4500-P F every 10 samples bracket 98 -102 one prior LCS in dup everyevery 10 sampleesvery 10 samples no acid

FIA less than LOQ samples published o sample analysis10 samples + end or matrix set or matrix set filter

Ortho-Phosphate 1 pre- + 0.003 6 to >/= 0.995 90 - 110 80 -120 [0 - 20] [90 - 110] 48 hours

SM4500-P E every 10 samples bracket 98 -102 one prior LCS in dup everyevery 10 sampleesvery 10 samples no acid

Color, Ascorbic less than LOQ samples published o sample analysis10 samples + end or matrix set or matrix set filter

Total Phosphorus low 1 pre- + 0.002 6 to >/= 0.995 90 - 110 80 -120 [0 - 10] [85 - 115] 28 days

SM4500-P E every 10 samples bracket 98 -102 one prior LCS in dup everyevery 10 sampleesvery 10 samples w /H2SO4

Color, Ascorbic less than LOQ samples published o sample analysis10 samples + end or matrix set or matrix set

Total Phosphorus high 1 pre- + 0.005 6 to >/= 0.995 90 - 110 80 -120 [0 - 20] [85 - 115] 28 days

SM4500-P E every 10 samples bracket 98 -102 one prior LCS in dup everyevery 10 sampleesvery 10 samples w /H2SO4

Color, Ascorbic less than LOQ samples published o sample analysis10 samples + end or matrix set or matrix set

BOD 1 dil. H20- 2.0 2 GGA 75 - 125 75 - 125 75 - 125 [0 - 30] [70 - 130] 48 hours

SM5210B 1 seed Bk published one prior every 10 samplesevery 10 sampleesvery 10 samples on ice

5 day, 20 C every 10 samples to sample analysis or at end or matrix set or matrix set

NOTE: Must meet 2.0 mg/L minimum DO depletion (initial minus final) and 1.0 mg/L residual (final) DO for each test bottle.

CBOD 1 dil. H20- 2.0 2 GGA 75 - 125 75 - 125 75 - 125 [0 - 30] [70 - 130] 48 hours

SM5210B 1 seed Bk published published one prior every 10 samplesevery 10 sampleesvery 10 samples on ice

5 day, 20 C every 10 samples in method o sample analysis or at end or matrix set or matrix set

NOTE: Must meet 2.0 mg/L minimum DO depletion (initial minus final) and 1.0 mg/L residual (final) DO for each test bottle.

Alkalinity 1 pre- + 1 min of 2 >/= 0.995 90 - 110 80 -120 [0 - 5] [85 - 115] 14 days

SM2320B every 10 samples bracket one prior every 10 samplesevery 10 sampleesvery 10 samples on ice

Titrimetric, pH 4.5 less than LOQ samples to sample analysis or at end or matrix set or matrix set

Chloride 1 pre- + 2 min of 2 >/= 0.995 90 - 110 80 -120 [0 - 4] [80 - 120] 28 days

SM4500Cl- B every 10 samples bracket one prior every 10 samplesevery 10 sampleesvery 10 samples on ice

Argentometric less than LOQ samples to sample analysis or at end or matrix set or matrix set

Conductivity 1 pre- + 2 min of 2 95-105 95-105 95-105 [0 - 2] N/A 28 days

EPA 120.1 every 10 sampl umhos/cm to bracket one prior every 10 samplesevery 10 samples on ice

Lab Meter less than LOQ samples to sample analysis or at end or matrix set

TDS 1 pre- + 10 1 [93 - 103] [93 - 103] N/A [0 - 6] N/A 7 days

SM2540C every 10 samples every 10 samples on ice

Gravimetric, 180 C less than LOQ or matrix set

NOTE: Dried to constant w eight-- w hen w eight change is less than 0.005 gm.

NOTE: Choose sample size to yield less than 200 mg residue.

TSS 1 pre- + 1 1 [80 - 120] [80 - 120] N/A [0 - 45] N/A 7 days

SM2540D every 10 samples every 10 samples on ice

Gravimetric, 104 C less than LOQ or matrix set

NOTE: Dried to constant w eight-- w hen w eight change is less than 0.005 gm.

NOTE: Choose sample size to yield betw een 2.5 & 200 mg residue and complete filtration time w ithin 10 min.

Sulfate 1 pre- + 5 12 >/= 0.995 90 - 110 90 -110 [0 - 20] 90 -110 28 days

EPA 375.2 every 10 samples to bracket one prior LCS in dup everyevery 10 sampleesvery 10 samples on ice

Color, MTB, FIA less than LOQ samples to sample analys10 samples or end or matrix set or matrix set

Turbidity 1 DI H2O 0.1 NTU 4 formazin 95 - 105 95 - 105 95 - 105 [0 - 5] N/A 48 hours

EPA 180.1 every 20 samples quarterly 2 gelex stds to 1 gelex every 10every 10 samples on ice

Turbidimeter less than LOQ bracket analysis samples or at end or matrix set

pH N/A N/A 2 or 3 to 95 - 105 +/- 0.2 units +/- 0.2 units 0 - 5 N/A analyze

EPA 150.1 bracket % efficiency immediately

Lab Meters samples of electrode

DO 1 initial +/- 0.5 mg/L 95 - 105 analyze

EPA 360.1 N/A N/A Water With chart N/A 1 end Water N/A N/A immediately

Field & Lab meters Sat air Sat air

Chlorophyll a 1 pre 1 1 N/A none N/A 0 - 30 N/A 21 days

filter/freeze

Color 1 pre 5 1 N/A none N/A 0 - 5 N/A 48 hours

filter/on ice
48

Appendix E – Parameter & Station Listing  

 

Parameters TOC

Station Historical Current

Date 10 * *

Time 20 * *

Sample Depth 25 *

Tide Stage 30 * *

32 *

Alkalinity 40 *

Ammonia 51 *

Chlorophyll-a corrected 60 * * *

Chlorophyll-a uncorrected 62 * * *

Color 63 *

Dissolved Oxygen 64 * *

Dissolved Oxygen % Saturation 65 * * *

Fecal Coliforms 67 * * *

Light % at 1 meter 68 *

Light % at 2 meter 69 * * *

Light Attenuation 72 * * *

Nitrate+Nitrite 74 *

Organic Nitrogen 75 * *

Orthophosphate 81 * * *

pH 86 * * *

Salinity 87 * * *

Secchi Disk Depth 88 usually dry *

Specific Conductance 92 *

Temperature

Total Kjeldahl Nitrogen 95 * *

Total Nitrogen 100 * * *

Total Organic Carbon 101 *

Total Phosphorus 104 *

Total Suspended Solids 105 * * *

Turbidity 107 * *

108 *

111 * *

112 * *

Notes:

All the parameters listed are analyzed on all the samples except for TOC and Ammonia.

In 2009 several ammonia stations were discontinued at the marine stations

 because occurance is rare; facilitated additional freshwater stations.

Ammonia
49

Appendix F – Quality Control Summary

Note: ‘I’, ‘P’ and ‘U’ qualifier codes not included 
Site # Date Time Analyte Method Code Data Qualifier Issue

10 10/21/2009 1259 TKN EPA351.2 J.3A+ Spike recovery above acceptable QC limits

10 10/21/2009 1259 TKN EPA351.2 V Analyte detected in the field blank

62 10/21/2009 1153 TKN EPA351.2 J.3A+ Spike recovery above acceptable QC limits

62 10/21/2009 1153 TKN EPA351.2 V Analyte detected in the field blank

65 10/21/2009 1111 TKN EPA351.2 J.3A+ Spike recovery above acceptable QC limits

65 10/21/2009 1111 TKN EPA351.2 V Analyte detected in the field blank

67 10/21/2009 1021 TKN EPA351.2 J.3A+ Spike recovery above acceptable QC limits

67 10/21/2009 1021 TKN EPA351.2 V Analyte detected in the field blank

69 10/21/2009 915 TKN EPA351.2 J.3A- Spike recovery below acceptable QC limits

69 10/21/2009 915 TKN EPA351.2 V Analyte detected in the field blank

72 10/21/2009 1227 TKN EPA351.2 J.3A- Spike recovery below acceptable QC limits

72 10/21/2009 1227 TKN EPA351.2 V Analyte detected in the field blank

92 10/21/2009 930 NH3 SM4500NH3C 18th ed J.3P % RPD of duplicates outside acceptable QC limits

92 10/21/2009 930 ortho P EPA365.2 J.3P % RPD is outside acceptable QC limits

92 10/21/2009 930 TKN EPA351.2 J.3A- Spike recovery below acceptable QC limits

92 10/21/2009 930 TKN EPA351.2 V Analyte detected in the field blank

95 10/21/2009 1030 TKN EPA351.2 J.3A- Spike recovery below acceptable QC limits

95 10/21/2009 1030 TKN EPA351.2 V Analyte detected in the field blank

100 10/21/2009 1030 TKN EPA351.2 V Analyte detected in the field blank

101 11/9/2009 849 CHL A SM10200-H Q Analyzed beyond acceptable hold time

106 11/9/2009 813 CHL A SM10200-H Q Analyzed beyond acceptable hold time

106 11/9/2009 813 ortho P EPA365.2 J.1+ % Recovery of standard is higher than acceptable QC limits

108 11/9/2009 837 CHL A SM10200-H Q Analyzed beyond acceptable hold time

108 11/9/2009 837 ortho P EPA365.2 J.1+ % Recovery of standard is higher than acceptable QC limits

111 11/9/2009 903 CHL A SM10200-H Q Analyzed beyond acceptable hold time

112 11/9/2009 930 CHL A SM10200-H Q Analyzed beyond acceptable hold time

10 11/16/2009 1025 CHL A SM10200-H Q Analyzed beyond acceptable hold time

20 11/16/2009 1010 CHL A SM10200-H Q Analyzed beyond acceptable hold time

25 11/16/2009 940 CHL A SM10200-H Q Analyzed beyond acceptable hold time

30 11/16/2009 1118 CHL A SM10200-H Q Analyzed beyond acceptable hold time

32 11/16/2009 1105 CHL A SM10200-H Q Analyzed beyond acceptable hold time

35 11/16/2009 1135 CHL A SM10200-H Q Analyzed beyond acceptable hold time

40 11/16/2009 1045 CHL A SM10200-H Q Analyzed beyond acceptable hold time

42 11/17/2009 1007 CHL A SM10200-H Q Analyzed beyond acceptable hold time

51 11/17/2009 950 CHL A SM10200-H Q Analyzed beyond acceptable hold time

55 11/17/2009 931 CHL A SM10200-H Q Analyzed beyond acceptable hold time

71 11/17/2009 1040 CHL A SM10200-H Q Analyzed beyond acceptable hold time

72 11/17/2009 1020 CHL A SM10200-H Q Analyzed beyond acceptable hold time

73 11/17/2009 1031 CHL A SM10200-H Q Analyzed beyond acceptable hold time

74 11/17/2009 1140 CHL A SM10200-H Q Analyzed beyond acceptable hold time

74 11/17/2009 1140 TKN EPA351.2 J.3A- Spike recovery below acceptable QC limits

75 11/17/2009 1128 CHL A SM10200-H Q Analyzed beyond acceptable hold time

67 11/24/2009 1000 TKN EPA351.2 J.3A+ Spike recovery above acceptable QC limits

95 11/24/2009 1113 NH3 SM4500NH3C 18th ed J.3A- Spike recovery below acceptable QC limits

107 11/24/2009 909 Total P EPA365.2 J.3A+ RPD of duplicates higher than acceptable QC limits

95 12/16/2009 1107 Fecal SM9222D B Colony count higher than acceptable range

10 1/19/2010 1030 Alk SM2320B Q Samples analyzed beyond acceptable hold time

20 1/19/2010 1000 Alk SM2320B Q Samples analyzed beyond acceptable hold time

25 1/19/2010 937 Alk SM2320B Q Samples analyzed beyond acceptable hold time

30 1/19/2010 1137 Alk SM2320B Q Samples analyzed beyond acceptable hold time

32 1/19/2010 1120 Alk SM2320B Q Samples analyzed beyond acceptable hold time

35 1/19/2010 1150 Alk SM2320B Q Samples analyzed beyond acceptable hold time

40 1/19/2010 1053 Alk SM2320B Q Samples analyzed beyond acceptable hold time

42 1/20/2010 1000 Alk SM2320B Q Samples analyzed beyond acceptable hold time

51 1/20/2010 1045 Alk SM2320B Q Samples analyzed beyond acceptable hold time

55 1/20/2010 1025 Alk SM2320B Q Samples analyzed beyond acceptable hold time

59 1/20/2010 1103 Alk SM2320B Q Samples analyzed beyond acceptable hold time

71 1/20/2010 928 Alk SM2320B Q Samples analyzed beyond acceptable hold time

72 1/20/2010 949 Alk SM2320B Q Samples analyzed beyond acceptable hold time

72 1/20/2010 949 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

73 1/20/2010 938 Alk SM2320B Q Samples analyzed beyond acceptable hold time

73 1/20/2010 938 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

74 1/20/2010 1136 Alk SM2320B Q Samples analyzed beyond acceptable hold time

74 1/20/2010 1136 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

75 1/20/2010 913 Alk SM2320B Q Samples analyzed beyond acceptable hold time

75 1/20/2010 913 CHL A SM10200-H J.3P RPD of duplicate outside acceptable QC limits

75 1/20/2010 913 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

101 1/20/2010 1023 Alk SM2320B Q Samples analyzed beyond acceptable hold time

101 1/20/2010 1023 TSS SM2540D Q Sample analyzed beyond acceptable hold time

101 1/20/2010 1023 Turb EPA180.1 Q Sample analyzed beyond acceptable hold time

106 1/20/2010 937 Alk SM2320B Q Samples analyzed beyond acceptable hold time

108 1/20/2010 958 Alk SM2320B Q Samples analyzed beyond acceptable hold time

111 1/20/2010 1038 Alk SM2320B Q Samples analyzed beyond acceptable hold time

111 1/20/2010 1038 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

Appendix F - Quality Control Summary

Page 1 of 4
Site # Date Time Analyte Method Code Data Qualifier Issue

Appendix F - Quality Control Summary

112 1/20/2010 1053 Alk SM2320B Q Samples analyzed beyond acceptable hold time

112 1/20/2010 1103 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

60 1/27/2010 1258 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

62 1/27/2010 1239 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

65 1/27/2010 1147 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

67 1/27/2010 1053 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

68 1/27/2010 947 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

69 1/27/2010 1003 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

69 1/27/2010 1003 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

81 1/27/2010 1338 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

81 1/27/2010 1338 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

86 1/27/2010 1322 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

86 1/27/2010 1322 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

87 1/27/2010 1315 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

87 1/27/2010 1315 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

92 1/27/2010 1202 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

92 1/27/2010 1202 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

95 1/27/2010 1214 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

95 1/27/2010 1214 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

100 1/27/2010 1105 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

104 1/27/2010 1128 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

105 1/27/2010 1038 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

105 1/27/2010 1038 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

107 1/27/2010 925 NH3 SM4500NH3C 18th ed V Analyte detected in the method blank

107 1/27/2010 925 TKN EPA351.2 J.3P RPD of duplicate outside acceptable QC limits

69 2/16/2010 934 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

92 2/16/2010 1011 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

95 2/16/2010 1055 CHL A SM10200-H J.3P RPD of duplicate outside acceptable QC limits

95 2/16/2010 1055 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

35 3/17/2010 1109 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

42 3/18/2010 1031 CHL A SM10200-H J.3P RPD of duplicate outside acceptable QC limits

60 3/22/2010 1248 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

62 3/22/2010 1228 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

63 3/22/2010 1212 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

64 3/22/2010 1159 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

65 3/22/2010 1132 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

66 3/22/2010 1109 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

67 3/22/2010 1042 NH3 SM4500NH3C 18th ed J.3P RPD of duplicate outside acceptable QC limits

67 3/22/2010 1042 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

69 3/22/2010 1010 NO2+NO3 EPA353.2 J.3A+ Spike recovery is higher than acceptable QC limits

100 3/22/2010 1054 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

59 3/23/2010 905 CHL A SM10200-H J.3P RPD of duplicate outside acceptable QC limits

59 3/23/2010 905 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

101 3/23/2010 825 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

106 3/23/2010 741 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

108 3/23/2010 803 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

111 3/23/2010 840 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

112 3/23/2010 855 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

62 4/15/2010 1145 NH3 SM4500NH3C 18th ed J.3P RPD of duplicate outside acceptable QC limits

62 4/15/2010 1145 NH3 SM4500NH3C 18th ed J.3A+ Spike recovery is higher than acceptable QC limits

62 4/15/2010 1145 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

81 5/12/2010 1220 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

100 5/12/2010 1019 NH3 SM4500NH3C 18th ed J.3P RPD of duplicate outside acceptable QC limits

100 5/12/2010 1019 ortho P SM4500-P E J.3P RPD of duplicate outside acceptable QC limits

101 5/13/2010 920 NO2+NO3 EPA353.2 J.3A- Spike recovery is lower than acceptable QC limits

101 5/13/2010 920 ortho P SM4500-P E J.3P RPD of duplicate outside acceptable QC limits

111 5/13/2010 945 NH3 SM4500NH3C 18th ed J.1+ Standard higher than acceptable QC limits

112 5/13/2010 1020 NH3 SM4500NH3C 18th ed J.1+ Standard higher than acceptable QC limits

40 5/18/2010 1104 TP SM4500-P E J.3P RPD of duplicate outside acceptable QC limits

73 5/19/2010 1003 ortho P SM4500-P E J.1+ Standard higher than acceptable QC limits

75 5/19/2010 907 NH3 SM4500NH3C 18th ed J.1+ Standard higher than acceptable QC limits

75 5/19/2010 907 ortho P SM4500-P E J.1+ Standard higher than acceptable QC limits

60 6/29/2010 1310 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

62 6/29/2010 1133 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

65 6/29/2010 1038 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

67 6/29/2010 950 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

69 6/29/2010 910 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

72 6/29/2010 1323 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

92 6/29/2010 936 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

95 6/29/2010 1028 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

100 6/29/2010 1000 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

10 7/7/2010 1030 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

20 7/7/2010 1015 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

25 7/7/2010 943 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

Page 2 of 4
Site # Date Time Analyte Method Code Data Qualifier Issue

Appendix F - Quality Control Summary

30 7/7/2010 1125 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

32 7/7/2010 1110 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

35 7/7/2010 1140 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

40 7/7/2010 1052 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

42 7/8/2010 1129 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

51 7/8/2010 1056 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

55 7/8/2010 1030 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

71 7/8/2010 1239 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

72 7/8/2010 1151 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

73 7/8/2010 1205 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

74 7/8/2010 1323 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

75 7/8/2010 1224 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

60 7/12/2010 1221 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

60 7/12/2010 1221 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

62 7/12/2010 1205 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

62 7/12/2010 1205 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

63 7/12/2010 1147 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

63 7/12/2010 1147 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

64 7/12/2010 1134 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

64 7/12/2010 1134 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

65 7/12/2010 1113 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

65 7/12/2010 1113 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

66 7/12/2010 1055 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

66 7/12/2010 1055 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

67 7/12/2010 1030 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

67 7/12/2010 1030 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

68 7/12/2010 1004 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

68 7/12/2010 1004 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

69 7/12/2010 1023 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

69 7/12/2010 1023 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

81 7/12/2010 1309 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

81 7/12/2010 1309 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

86 7/12/2010 1219 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

86 7/12/2010 1219 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

87 7/12/2010 1211 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

87 7/12/2010 1211 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

88 7/12/2010 1258 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

88 7/12/2010 1258 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

92 7/12/2010 1127 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

92 7/12/2010 1127 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

95 7/12/2010 1139 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

95 7/12/2010 1139 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

100 7/12/2010 1040 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

100 7/12/2010 1040 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

104 7/12/2010 1103 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

104 7/12/2010 1103 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

105 7/12/2010 1035 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

105 7/12/2010 1035 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

107 7/12/2010 942 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

107 7/12/2010 942 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

101 7/20/2010 954 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

101 7/20/2010 954 NO2+NO3 EPA353.2 J.1- % Recovery of end standard lower than acceptable QC limits

101 7/20/2010 954 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

101 7/20/2010 954 ortho P SM4500-P F V Analyte detected in the method blank

106 7/20/2010 920 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

106 7/20/2010 920 NO2+NO3 EPA353.2 J.1- % Recovery of end standard lower than acceptable QC limits

106 7/20/2010 920 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

106 7/20/2010 920 ortho P SM4500-P F V Analyte detected in the method blank

108 7/20/2010 933 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

108 7/20/2010 933 NO2+NO3 EPA353.2 J.1- % Recovery of end standard lower than acceptable QC limits

108 7/20/2010 933 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

108 7/20/2010 933 ortho P SM4500-P F V Analyte detected in the method blank

111 7/20/2010 1006 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

111 7/20/2010 1006 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

111 7/20/2010 1006 ortho P SM4500-P F V Analyte detected in the method blank

112 7/20/2010 1019 TKN EPA351.2 J.3A- Spike recovery is lower than acceptable QC limits

112 7/20/2010 1019 NO2+NO3 EPA353.2 J.1- % Recovery of end standard lower than acceptable QC limits

112 7/20/2010 1019 Total P SM4500-P E Q Sample analyzed beyond acceptable hold time

112 7/20/2010 1019 ortho P SM4500-P F V Analyte detected in the method blank

72 8/25/2010 1210 TKN EPA351.2 J.3A+ Spike recovery is higher than acceptable QC limits

60 9/8/2010 1131 TKN EPA351.2 J.3PA+ Matrix duplicate & spike recoveries higher than acceptable QC limits

62 9/8/2010 1115 TKN EPA351.2 J.3PA+ Matrix duplicate & spike recoveries higher than acceptable QC limits

63 9/8/2010 1059 TKN EPA351.2 J.3PA+ Matrix duplicate & spike recoveries higher than acceptable QC limits

64 9/8/2010 1046 TKN EPA351.2 J.3PA+ Matrix duplicate & spike recoveries higher than acceptable QC limits

Page 3 of 4
Site # Date Time Analyte Method Code Data Qualifier Issue

Appendix F - Quality Control Summary

65 9/8/2010 1031 TKN EPA351.2 J.3PA+ Matrix duplicate & spike recoveries higher than acceptable QC limits

66 9/8/2010 1009 TKN EPA351.2 J.3PA+ Matrix duplicate & spike recoveries higher than acceptable QC limits

67 9/8/2010 946 TKN EPA351.2 J.3PA+ Matrix duplicate & spike recoveries higher than acceptable QC limits

100 9/8/2010 957 TKN EPA351.2 J.3PA+ Matrix duplicate & spike recoveries higher than acceptable QC limits

108 9/22/2010 914 Total P SM4500-P E J.3P % RPD of matrix duplicate outside acceptable QC limits

72 9/23/2010 1026 TKN EPA351.2 J.3A- % Recovery of matrix spike is lower than acceptable QC limits

Page 4 of 4