9

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# Implementation of

Florida’s Numeric Nutrient Standards

Document Submitted to EPA in Support of the Department of

Environmental Protection’s Adopted Nutrient Standards for
Streams, Spring Vents , Lakes, and Selected Estuaries

September 20129

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ii 

# T

**ABLE OF** 

# C **ONTENTS**

Purpose of Document

................................ ................................ ................................ ............ 1

Background

................................ ................................ ................................ ........................... 1

The Hierarchical Approach

................................ ................................ ................................ ..... 1

Nutrient Criteria for Lakes

................................ ................................ ................................ .............. 2

Nitrate

- Nitrite Criterion for Spring Vents

................................ ................................ ......................... 4

Using Measures of Flora and Fauna and Regional Nutrient Thresholds in Streams

............................ 5

Stream Definition

................................ ................................ ................................ ................... 5

Implementation o f NNC in Streams

................................ ................................ ........................ 6

Floral Evaluation for Determining Achievement of NNC

................................ .......................... 8

Evaluating Algal Mats

................................ ................................ ................................ ........... 10

RPS Decision Key

................................ ................................ ................................ ................... 10

Evaluating Chang es in Species Composition

................................ ................................ .......... 11

Algal Species Composition Decision Key

................................ ................................ ............... 12

Evaluating the Presence or Absence of Nuisance Macrophyte Growth

................................ ... 12

LVS Decision Key

................................ ................................ ................................ ................... 13

Evaluating Algal Blooms, Chlorophyll a, and Phytoplankton Taxonomic Data

......................... 14

Chlorophyll/Algal Bloom Decision Key

................................ ................................ ................. 15

Flor al Measures Summary

................................ ................................ ................................ .... 16

Faunal Evaluation for Determining Achievement of NNC

................................ ....................... 16

Examples of a Weight

- of

- Evidence Approach for Determining Achievement

of Nutrient Criteria

................................ ................................ ................................ ............... 17

Stream Sampling Locations and Other Environmental Considerations

................................ ... 20

Nutrient Criteria in Estuaries

................................ ................................ ................................ ......... 21



### Decision Matrix and Examples for Implementing the Hierarchical Process

............................ 21

Hierarchies 1 and 2

................................ ................................ ................................ ....................... 24

Examples of Hierarchy 1

................................ ................................ ................................ ....... 24

Examples of Hierarchy 2

................................ ................................ ................................ ....... 24

Hierarch y 3

................................ ................................ ................................ ................................ ... 25

Examples of Hierarchy 3

................................ ................................ ................................ ....... 269

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iii Waterbody Types and Cases with Insufficient Information

................................ ............................. 28

Other Components of NNC

................................ ................................ ................................ ............ 28

NNC and Protection of Downstream Waters

................................ ................................ .................. 29

Water Quality Modeling

................................ ................................ ................................ ....... 29

Issuance of NPDES Permits

................................ ................................ ................................ ... 29

Evalua tion of Trends

................................ ................................ ................................ ............ 30

Trend Test Summary

................................ ................................ ................................ ............ 32

Discussion of TMDLs as NNC

................................ ................................ ................................ ......... 33

Discussion of Site Specific Alternative Criteria as NNC

................................ ................................ .... 34



### Implementing the NNC Revisions to the Impaired Waters Rule (Chapter 62

- 303, F.A.C.)

....... 35

Assessment of Estuaries

................................ ................................ ................................ ................ 40

Assessment of Waterb odies with Interpretations of the NNC Expressed as Loads or Delivery

Ratios

................................ ................................ ................................ .............................. 41

Impaired Waters Rule Assessment Summary

................................ ................................ ........ 41



### Surface Water Discharge Wastewater Permits

................................ ................................ ..... 42

WQBEL Procedures for Each Tier of the Hierarchy

................................ ................................ . 43

Appendix A. Minimally Disturbed and Healthy Streams

................................ ................................ 49

Table A

- 1. List of healthy streams (passing SCI) used to inform RPS expectations.

............ 49

Table A

- 2. List of benchmark streams used to establish RPS and LVS
expectations.

................................ ................................ ................................ ................ 55

Table A

- 3. List of healthy streams (passing SCI) used to inform stream
chlorophyll a expectations.

................................ ................................ .......................... 56

Table A

- 4. List of benc hmark streams used to establish stream chlorophyll a
expectations.

................................ ................................ ................................ ................ 64

Appendix B. Department’s Algal Bioassessment and Autecological References, 2012

.................... 749

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1 

# P **URPOSE OF** 

# D **OCUMENT**

This document describes how numeric nutrient standards in Chapters 62

- 302 (Water Quality Standards)

and 62

- 303 (Identification of Impaired Surface Waters), Florida Administrative Code (F.A.C.)

, are implemented by the Department of Environmental Protection (D epartment ). The major topics include

the hierarchical approach used to interpret the narrative nutrient criteri on (NNC) on a site

- specific basi s ;

a summar y of the criteria for lakes, spring vents, streams and estuaries ; floral measures and the weight of evidence approach in streams ; example scenario s for how the criteria will be implemented in the 303(d) assessment process ; and a description of how the Water Quality Based Effluent Limitation (WQBEL) process is used to implement the nutrient standards in wastewater permitting

. Finally, because of the complexit y associated with assessing nutrient enrichment effects in streams, a summary of the weight

- of

- evidence evaluation involving flora, fauna, and Nutrient Thresholds is provided.



# B **ACKGROUND**

Nutrients are naturally present in aquatic systems and are necessary for the proper functioning of
biological communities. Nutrient effects on aquatic ecosystems are moderated in how they are expressed by many natural factors (e.g., light penetration, hydraulic residence time, presence of herbivore grazers and other food web interactions, and habitat considerations). As a result, determining
the appropriate protective nutrient regime is largely a site

- specific undertaking, requiring information
about ecologically relevant responses.



# T

**HE** 

# H **IERARCHICAL** 

# A **PPROACH**

The NNC in paragraph 62

- 302.530(47)(b), F.A.C., states that “in no case shall nutrient concentrations of a body of water be altered so as to cause an imbalance in natural populati ons of aquatic flora or fauna.” The method for numerically interpreting this NNC , on a site

- specific basis, is provided in Rule 62

- 302.531, F.A.C, using a hierarchical process ( Figure 1 ). This hierarchical scheme specifies a prioritization for determining the numeric nutrient criteria that apply to a given waterbody.

The Rule’s hierarchic al approach gives preference to site specific analyses that result in a numeric interpretation of the NNC

. Site specific interpretations are generally deemed superior to more broadly applicable interpretations of the NNC b ecause of the many natural factor s affect ing the expression of nutrient loadings on a given waterbody

. Beginning at the top of Figure 1, if there is a site specific interpretation of the narrative, such as a Total Maximum Daily Load (TMDL), Site Specific Alternative Criterion (SSAC), Wat er Quality Based Effluent Limitation (WQBEL), or other D epartment

- approved

action that numerically interprets the narrative criterion ( e.g ., Reasonable Assurance derived values)

, that numeric interpretation is the applicable nutrient criteri on 1

. These num eric interpretations of the

narrative criterion must establish the total allowable load or ambient concentration for at least one nutrient that represents achievement of a healthy, well balanced aquatic community. E ach nutrient (TP

1 Consistent with the Clean Water Act, these site

- specific interpretations will be submitted to EPA for review.9

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2 and TN) is interpreted independently using this hierarchical approach ; if the site

- specific interpretation
only addresses one nutrient, then the generally applicable numeric interpretations in subsections 62

- 302.531(2) and (3), F.A.C., will apply for the other nutrient

.

If a hie rarchy 1 interpretation is not available

, the Rule’s hierarchical approach then gives preference to

numeric nutrient values based on quantifiable stressor

- response relationships between nutrients and biological response ( i.e

., springs and lakes ). If no qu antifiable stressor

- response relationship has been
established, such as is the case for Florida streams , reference

- based Nutrient Thresholds

, in conjunction with biological information

, are used to determine the applicable interpretation of the NNC

. For t hose waters without a numeric interpretation under any of these approaches , the NNC continues to apply to the waterbody.

Figure 1 . The hierarchy for numerically interpreting the NNC

.



## Nutrient Criteria for Lakes

The l akes criteria were based on a strong stressor

- response relationship between nutrients ( TN and TP ) and phytoplankton response (chlorophyll a ). The lakes chlorophyll criteria were derived using multiple lines of evidence, and result in maintaining naturally low nutrient lakes in an oligotrophic state and lakes with naturally moderate nutrient levels in a mesotrophic state. Naturally eutrophic lakes are addressed9

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3 on a site

- specific basis. A “lake” is defined, for purposes of interpreting the NNC in paragrap h 62

- 302.530(47)(b), F.A.C., as a lentic fresh waterbody with a relatively long water residence time and an open water area that is free from emergent vegetation under typical hydrologic and climatic conditions. Aquatic plants, as defined in subsection 62

- 340.200(1), F.A.C., may be present in the open water. Lakes do not include springs, wetlands, or streams (except portions of streams that exhibit lake

- like characteristics, such as long water residence time, increased width, or predominance of biological taxa typically found in non

- flowing conditions). Note that while lakes are typically characterized by a fringe of emergent vegetation, the presence of an open water area, where emergent vegetation is absent, distinguishes lakes from wetlands. Floating or submersed vegetation may be present in this open water area, and the system would still be defined as a lake, and numeric nutrient criteria would apply.

For lakes, the applicable numeric interpretations of the NNC in paragraph 62

- 302.530(47)(b), F.A.C., for
chlorophyll a are shown in Table 1

. The Department allows for an acceptable range of annual geometric means of TN and TP, up to the values shown in the “maximum calculated numeric interpretation”
column, as long as the applicable chlorophyll a criteri on is achieved in that same year . These numeric interpretations for TN, TP, and chlorophyll a can not be exceeded more than once in any consecutive

calendar three year period and apply statewide

.

Table 1. Lakes chlorophyll a , TN, and TP criteria.

1 For lakes with color > 40 PCU in the West Central Nutrient Watershed Region, the maximum TP limit is 0.49 mg/L

, which is the TP streams threshold for the region.9

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4 If there are insufficient data to calculate the annual geometric mean chlorophyll a for a given year or the annual geometric mean chlorophyll a exceeds the values in Table 1 for the lake type, then the applicable numeric interpretations for TN and TP are the minimum values in the table. I f there are sufficient data
to calculate the annual geom etric mean chlorophyll a and the mean does not exceed the chlorophyll a value for the lake type in T able 1 , then the TN and TP numeric interpretations for that calendar year are the annual geometric means of ambient TN and TP samples for that lake , subject to the minimum and

maximum TN and TP limits in the table.

If a lake is influenced by an upstream NPDES discharger, the Water Quality Based Effluent Limitation (WQBEL) evaluation for that discharge would determine the specific TN and TP levels ( again subject to the upper nutrient values for TN and TP) that would maintain the appropriate chlorophyll a target for the lake (6 or 20 μg/L) during all years, including years representing critical conditions

. This evaluation would involve water quality modeling set to achieve a “never to exceed” chlorophyll target scenario. The Department evaluated the inter

- annual variability in lake chlorophyll a levels and found that inter

annual standard deviation (natural log

- transformed) typically ranges from 0.30 5 to 0.533. Given this level of variability, the long

- term geometric chlorophyll a concentration in a colored or alkaline clear lake would need to be between 12.8 and 15.5 μg/L to be consistently found in compliance with the
chlorophyll a standard of 20 μ g/L. Consequently, the numeric nutrient permit limits for a point source discharger that influences a downstream lake would need to be adjusted to ensure attain ment of chlorophyll a targets in this lower range during all years

, with the precise permit lim its being depend ent upon site specific factors

. If this demonstration of attainment cannot be made, the discharger could pursue other options, which include effluent nutrient reductions, discharge re

- location ( e.g., land application), or a Site Specific Alternative Criterion ( establish alternate chlorophyll and nutrient targets

that are fully protective of designated uses).

Note that for lakes with color > 40 PCU in the West Central Nutrient Watershed Region, the re lationship between chlorophyll a and TP is sufficiently variable such that the maximum allowable TP based on the upper prediction interval would be higher than the TP nutrient threshold for streams. To ensure protection of downstream streams, the maximum TP limit was set at 0.49 mg/L , which is the TP streams

threshold for the region.



## Nitrate

- N itrite Criterion for Spring Vents

The spring vent nitrate

- nitrite criterion is based on a strong stressor

- response relationship between

nitrate

- nitrite and the presence of nuisance algal mats, with the criterion established at a concentration that would prevent nuisance mats from occurring (compared with natural background levels). A “spring

vent” is defined as a loc ation where groundwater flows out of a natural, discernible opening in the ground onto the land surface or into a predominantly fresh surface water.

For spring vents, the applicable numeric interpretation of the NNC in paragraph 62

- 302.530(47)(b),
F.A.C., is 0.35 mg/L of nitrate

- nitrite (NO3 + NO2) as an annual geometric mean, not to be exceeded
more than once in any three consecutive calendar year period.9

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5 

## Using Measures of Flora and Fauna and R egion al Nutrient Thresholds in Streams

Despite an exhaustive ef fort to develop stressor

- response relationships between nutrients and biological responses in streams, insufficient responses were observed to develop numeric nutrient
criteria. Therefore, t o assess whether a stream attains the NNC in paragraph 62

- 302.530( 47)(b), F.A.C., pursuant to the provisions in paragraph 62

- 302.531(2)(c), F.A.C. , an evaluation of water chemistry,
biological data (flora and fauna)

, and physical information is used to determine if a stream’s nutrient

concentrations are protect ive of ba lance d flora and fauna. Because of the complexity associated with nutrient enrichment effects, no single assessment tool is adequate to evaluate all potential impacts, and
instead, a weight

- of

- evidence evaluation must be conducted , as described in Section 2.7 of Sampling and Use of the Stream Condition Index (SCI) for Assessing Flowing Waters: A Primer (DEP

- SAS

- 001/11)

, which was incorporated by reference in the rule

. The final result allows a scenario in which the TN and/or TP th resholds are exceeded, but because the floral and faunal measures are met, the streams are

found to be healthy and well balanced . In those occasions, the Department will provide information to
the public on the TN and TP levels that would be associated wi th the well

- balanced aquatic community.



### S TREAM 

### D EFINITION

For purposes of interpreting the NNC in paragraph 62

- 302.530(47)(b), F.A.C., under paragraph 62

- 302.531(2)(c), F.A.C., a “stream” is defined as a predominantly fresh surface waterbody with perennial flow in a defined channel with banks during typical climatic and hydrologic conditions for its region

within the state. During periods of drought, portions of a stream channel may exhibit a dry bed, but
wetted pools are typically still present during the se conditions. Streams do not include: (a) non

perennial water segments where fluctuating hydrologic conditions, including periods of desiccation, typically result in the dominance of wetland and/or terrestrial taxa (and corresponding reduction in
obligat e fluvial or lotic taxa), wetlands, or portions of streams that exhibit lake characteristics (e.g., long water residence time, increased width, or predominance of biological taxa typically found in non

- flowing conditions), or tidally influenced segments th at fluctuate between predominantly marine and predominantly fresh waters during typical climatic and hydrologic conditions; or (b) ditches, canals and other conveyances, or segments of conveyances, that are man

- made, or predominantly channelized or predomi nantly physically altered; and 1) are primarily used for water management purposes, such as flood protection, stormwater management, irrigation, or water supply; and 2) have marginal or poor stream habitat or habitat components, such as a lack of habitat o r substrate that is biologically limited, because the conveyance has cross sections that are predominantly trapezoidal, has armored banks, or is maintained primarily for water conveyance.

This stream definition applies only to the numeric nutrient criteria for streams adopted at paragraph 62

- 302.531(2)(c)

, F.A.C. (hereafter referred to as paragraph (2)(c)). The definition does not apply to any
other water quality criteria adopted within Florida rules except those that specifically reference paragraph (2)(c ). Rule 62

- 302.531(1), F.A.C.

, states that the NNC continues to apply for those waters

without numeric nutrient criteri on

.9

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6 The stream definition in Rule 62

- 302.200(36), F.A.C.

, was carefully crafted to ensure consistency with the scientific procedures and methods used to establish the numeric nutrient standards expressed in paragraph (2)(c). Neither canals nor non

- perennial streams were used in the derivation of the nutrient

th resholds in paragraph (2)(c). Furthermore, the physical and hydrologic alterations within a canal would almost always result in the failure of the SCI component of the standards in paragraph (2)(c) , regardless

of nutrient levels

. This limits the utility o f the SCI for determining the affects of nutrients in canals. Based on these considerations, the Department chose not to extend the standards in paragraph (2)(c) to

canals and non

- perennial streams at this time

.



### I MPLEMENTATION OF 

### NNC IN 

### S TREAMS

To evaluat e ecosystem health in streams , it is important to acknowledge that adverse nutrient enrichment effects follow a conceptual ecological model ( Figure 2 ). When anthropogenic nutrient loading or concentrations exceed a system’s assimilative capacity, the prim ary response consists of changes to the primary producer communities (periphyton, phytoplankton, or vascular plants), and excess production of plant biomass. In turn, this enhanced floral biomass can lead to habitat loss ( e.g ., from excess periphyton smoth ering or nuisance plant biomass accumulation), food web alterations ( e.g ., dominance of taxa that thrive in nutrient/organic matter enriched conditions), and/or low dissolved oxygen (DO) from decomposition of plant biomass or respiration. This chain of ev ents is ultimately reflected in meaningful biological endpoints, such as excessive algal mats, excess water column
chlorophyll a , excess nuisance vascular plant growth, and/or failing Stream Condition Index (SCI) scores.
These adverse biological endpoints constitute imbalances of aquatic flora and/or fauna.

Conversely, if data show that biological health is fully supported in an aquatic system (no adverse responses consistent with the ecological model), one may conclude that the associated nutrient regi me is inherently protective of the waterbody, and the NNC is achieved.

For streams, if a site specific interpretation pursuant to paragraph 62

- 302.531(2)(a), F.A.C. (TMDL, SSAC, Level II WQBEL or RA Plan) has not been established, Nutrient Thresholds are used to interpret the NNC in combination with biological information. The NNC in paragraph 62

- 302.530(47)(b), F.A.C., shall be interpreted as being achieved in a stream segment if:

• Information on chlorophyll a levels, algal mats or blooms, nuisance macrophyte growth, and changes in algal species composition do not indicate an imbalance in flora or fauna;

AND EITHER

• The average score of at least two temporally independent SCIs performed at representative locations and times is 40 or higher, with neith er of the two most recent SCI scores less than 35 (i.e., no faunal imbalances), OR

• The Nutrient Thresholds (expressed as annual geometric means) in Table 2 are not exceeded more than once in a three year period (see Figure 3 for regions).9

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7 Figure 2 . Si mplified nutrient enrichment conceptual model used to assess potential adverse effects of nutrients on aquatic life and human uses in streams. Relationships between nutrients and biological responses are highly influenced by site

- specific and mitigating f actors.

Table 2

. Reference s tream

- based n utrient t hresholds

.

Nutrient Region Total Phosphorus Threshold Total Nitrogen Threshold Panhandle West 0.06 mg/L 0.67 mg/L
Panhandle East 0.18 mg/L 1.03 mg/L North Central 0.30 mg/L 1.87 mg/L
Peninsula 0.12 mg/L 1.54 mg/L West Central 0.49 mg/L 1.65 mg/L South Florida No numeric nutrient threshold. The narrative criterion in paragraph 62

- 302.530(47)(b), F.A.C., applies. 2

2 Chlorophyll a impairment thresholds in the IWR will continue to be used to assess South Florida flowing waters.9

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8 Figure 3. Map of s tream n utrient r egions

.



### F LORAL 

### E VALUATION FOR 

### D ETERMINING 

### A CHIEVEMENT OF 

### NNC

During numeric nutrient criteria development, the Department, in coordination with EPA, conducted a series of comprehensive statistical analyses to identify relationships between human disturbance (including nu trient enrichment) and adverse floral responses ( e.g., algal taxonomic composition, algal and vascular plant abundance, chlorophyll a, etc.) using an extensive data set collected in Florida

streams

. The relationships were statistically weak, and neither the Department nor EPA could identify

floral health/ impairment thresholds associated with human disturbance or nutrient concentrations/load

. The Department will continue these investigations, and if a relationship is eventually found, then stream floral measures would be strong candidates for Biocriteria, similar to the

Stream Condition Index and Lake Condition Index . Until these Biocriteria are developed

, the
Department ’s approach is to determine whether the floral components at a given stream ar e consistent

with the flora l measures found within the EPA reference stream distribution (generally the 90 th
percentile, as was used to develop the nutrient thresholds)

. If all floral measures are within the EPA reference site distribution, one may reason ably conclude the presence of a balanced floral community

. Based on all potential floral outcomes associated with the conceptual model in Figure 2 , the Department evaluate s the Rapid Periphyton Survey (RPS )

, community composition ( autecological )

information associated with dominant algal taxa , Linear Vegetation Survey (LVS), and chlorophyll a data
using a weight of evidence approach, as described below

. These assessments were chosen because they:

• Represent the entire range of potential floral re sponses to nutrients , consistent with the nutrient enrichment conceptual model in Figure 2 ;

• May routinely be conducted by Department staff, who have been extensively trained in
the associated Standard Operating Procedures (SOPs) ; and9

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9 • Comprise the most adv anced floral assessment tools currently available for the State of

Florida.

In addition to comparing water quality data to the stream nutrient thresholds in Table 2 and evaluating

available SCI data , the Department evaluate s the floral components, describe d below, to determine if

the stream exhibits balanced flora. Although a weight of evidence approach is used (generally using

floral thresholds established at the 90 th or 10 th percentile of the EPA reference stream distribut ion, depending on the metric), if any one these floral measures indicates an imbalance, then the Department

w ould conclude that the stream does not attain the NNC

. Floral measures alone can provide e vidence

that the nutrient standard at Rule 62

- 302.531(2)( c) is not achieved

, leading to the waterbody being placed on the Florida Verified List and Clean Water Act 303(d) list

.

If floral data are unavailable for a stream that exceed s the Nutrient Thresholds , it is the Depa rtment’s

intent to collect the information during the Watershed Management Assessment Cycle associated with
the Impaired Waters Rule. If the necessary information is not collected during the assessment cycle (due to logistical considerations, etc.) and either the TN or TP thresholds ar e exceeded , the Department place s such waters on the Study List , which is submitted to EPA as part of the 303(d) list of impaired

waters , until conclusions can be made

.

To conduct a conclusive biological evaluation of the floral community, it is necessary to conduct two floral evaluations using the metrics described below to address the temporal persistence . One

evaluation is not sufficient to document a s tream ’ s long term floral health because natural climate

related circumstances during any given time p eriod can cause shifts in the vascular plant and algal

communit ies . Collecting a temporally independent sample can further minimize Type 1 and Type 2

error.

When evaluating the floral evidentiary thr e sholds described below, comparisons to contemporaneous floral data from minimally disturbed reference streams (with minimal disturbance being based on the same criteria employed by EPA during nutrient threshold development) is an important component of
the process. T he expression of nutrient responses is very complex

, and could be related to many
natural factors

, such as extended low flow periods (increased residence time), natural variation in grazer populations, changes in light penetration, and system morphology. For this reason, it is im portant to assess how floral metrics fluctuate at reference sites that are sampled under environmental and climatological conditions similar to any test site being evaluated. The RPS, LVS, algal species
composition , and chlorophyll data from reference stre am s located proximal ly to any stream under

evaluation should be considered as part of the evidentiary process. Algal evaluations are complex and should be considered with regard to all the variables described above ; however , the Department has
provided a decision key for each of the metrics to assist with decision making

.9

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10 

### E VALUATING 

### A LGAL 

### M ATS

The RPS is used to quantify the extent (coverage) and abundance ( thickness) of attached algae (periphyton) and is an effective tool to quantify abundance of nuisance or problematic algal growth

. The
Department compare s RPS results from a stream to the RPS results compiled from the population of
minimally disturbed and healthy sites that was sampled by the Department as part of NNC development (s ee Appendix A for list of reference sites and biologically healthy sites). RPS rank 4

- 6 coverage (Rank 4

- 6 represent epiphyte lengths of > 6 mm) at Nutrient Benchmark streams ranged from 0% to 66%, with a

mean value of 6% and a 90 th percentile value of 25%. RPS rank 4

- 6 coverage at all biologically healthy sites (as indicated by S tream C ondition I ndex scores > 40), ranged from 0% to 91%, with a mean value of

8% and a 90 th percentile value of 32%. Although these RPS distributions a re fairly similar, the Department concluded that use of an RPS evidentiary threshold based on the 90 th percentile of the EPA

reference sites would be consistent with the manner in which the nutrient thresholds were derived.
Therefore, i f a stream exhibits a percent coverage for RPS ranks 4

- 6 of 25 % or less in both samples , the

RPS results indicate evidence of no imbalance of flora

. If a stream segment exceeds an RPS 4

- 6 coverage

of > 25 % during two consecutive, temporally independent samplings (> 3 months apart)

, the Department

considers this a s evidence that the NNC is not achieved.

If the two samples have differing results in relation to the evidentiary threshold, then the preliminary analysis of this metric alone is inconclusive. Reviewing o ther data, information, or water quality/biology
variables can help inform the reasons behind the differing results. Additional sampling should be conducted until two temporally independent samplings either attain, or do not attain, the evidentiary

thresh olds, so a final decision can be made.

Where the RPS 4

- 6 coverage is greater than 20%, an evaluation of the algal species composition (identifying the five most dominant taxa) is also conducted to provide additional information whether

there is no imbalan ce of flora. Where RPS 4

- 6 coverage is <20%, there is no need to collect samples for
algal species composition because the stream is clearly within the reference site distribution , and
therefore, the algal species composition is presumed to be acceptable

.


### RPS Decision Key

1. Were environmental conditions associated with the RPS samples representative of the typical conditions of the system? (e.g., flow between 10 th and 90 th percentile of long term discharge, light penetration characteristic of system, sampling location representative of waterbody segment, etc). 1a. Yes, proceed to couplet 2. 1b. No. Collect additional RPS samples at representative locations and during rep resentative

conditions

, and return to couplet 1.

2. Results of two temporally independent RPS samplings show that RPS rank 4

- 6 is 25% or less? 2a. Yes. Evidence that the waterbody achieves the algal mat component of floral measures (other components must still be evaluated). If RPS rank 4

- 6 results are between 20% to 25%,9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

11 then algal species composition will also be evaluated (see algal species composition decision key).
2b. No, evidence that the nutrient standard at 62

- 302.531(2)(c ) is not achieved

.



### E VALUATING 

### C HANGES IN 

### S PECIES 

### C OMPOSITION

Changes in algal species composition (through an analysis of autecological information) are also evaluated using the references in Appendix B

. While many of the references are for studies conducted in other States and other countries, they still provide valuable information concerning nutrient

enrichment in Florida because many of the indicator algal species are distributed worldwide and have

bee n shown to have consistent sensitivity to nutrients wherever found . For example, analyses in the Florida Everglades using algal autecological information derived from the prevailing literature showed
distinct responses to TP enrichment, analogous to the s ignal generated through site=specific TP dosing studies ( http://www.dep.state.fl.us/water/wqssp/everglades/pctsd.htm )

Although the Department conducted a comprehensive study of stre am periphyton in Florida in an attempt to formulate a multi

- metric index f or assessing human disturbance ( including nutrient effects )

, the statewide data indicated that that the periphyton community composition was more highly correlated with pH (and condu ctivity) than to nutrients or measures of human disturbance.
Additionally, common metrics that typically decrease in response to human disturbance in invertebrate
communities, such as taxa richness and diversity

, often increase in algal communities when comparing oligotrophic to eutrophic streams , meaning such metrics are not useful for assessing anthropogenic nutrient inputs. Given these constraints

, the Department assesses the environmental information

associated with dominant al gal taxa qualitatively using the scientific literature to determine if they are
indicat ive of nutrient enriched/ imbalanced conditions

.

For example, nutrient enriched Florida springs are typically characterized by an abundance of one or
more of the follow ing taxa: Lyngbya wollei, Oscillatoria sp. , Aphanothece sp., Phormidium sp.,
Vaucheria sp. , Spirogyra sp., Cladophora sp. , Rhizoclonium sp

. , Dichotomosiphon sp., Hydrodiction sp., Enteromorpha sp., and Chaetomorpha sp. Other algal indicators of nutrient enrichment from the

literature include: Anabaena sp., Euglena sp., Chlamydomonas sp., Scenedesmus sp., Chlorella sp., Rhopalodia spp., Gomphonema spp., Cosmarium sp. Nitzschia spp., Navicula spp., and Stigeoclonium sp. ( see references in Appendix B)

. Do min ance of such taxa at a stream where the RPS rank 4

- 6 >2 0 % would

be evidence that the NNC is not achieved.

As another example of this approach , the Everglades TP criterion was largely based on observed shift s in

the dominan t algal taxa from those characteristic of reference conditions ( e.g ., Scytonema sp. , Schizothrix sp.) to taxa indicative of nutrient enriched conditions ( e.g ., Gomphonema parvulum

, Navicula minima

, Nitzschia amphibia

, Nitzschia palea

, Oscillatoria sp ., Rhopalodia gibba

, Scenedesmus

sp ., Anabaena sp. , Cosmarium sp ., and Lyngbya woll ei). As mentioned earlier, this change in algal
species composition due to nutrient enrichment was supported by using the general (worldwide) autecological references.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

12 Because a statewide analysis of algal community metric s (including the percentage of pollution sensitive and pollution tolerant taxa) failed to correlate well (r 2 < 0.1) with human disturbance, this evaluation of algal community composition in streams must be co nd ucted on a site

- specific basis, using the references
in Appendix B

. During this assessment , the natural ionic regime (pH, conductivity) should be taken into

account because past studies indicate that pH and conductivity significantly influence the algal
community composition . Because of the variability associated with algal species composition, site

specific responses are emphasized as part of the weight of evidence approach

. Additional sampling

sho uld be conducted until two temporally independent samplings either attain, or do not attain, the evidentiary thresholds , so a final decision can be made.



### Algal Species Composition Decision Key

1. Were environmental conditions associated with the RPS sa mples and algal taxonomic collections representative of the typical conditions of the system? (e.g., flow between 10 th and 90 th

percentile of long term discharge, light penetration characteristic of system, sampling location representative of waterbody segment, etc.).
1a. No. Collect additional RPS samples and algal taxonomic composition samples at representative locations and during representative conditions, and return to couplet 1. 1b. If Yes, see couplet 2.

2. Results of two temporally independent RPS samplings show that RPS rank 4

- 6 is 20% or less?

2 a. Yes. Evidence that the waterbody achieves the algal species compos ition component of f

loral measures (other components must still be evaluated).

2 b. If No , see couplet 3

.

3

. Do dominant taxa 3 of algal community include taxa known to be nutrient enrichment

indicators ? (see list above and references in Appendix)

. 3 a. Yes. Evidence that the nutrient standard at Rule 62

- 302.531(2)(c) is not achieved

. 3 b. No . This is evidence that the waterbody achieves the algal species composition component of floral measures (other components must still be evaluated )

.



### E VALUATING THE 

### P RESENCE OR 

### A BSENCE OF 

### N UISANCE 

### M ACROPHYTE 

### G ROWTH

Another line of evidence to determine if streams are healthy is determining the relative lack of nuisance macrophyte growth by certain vascular plant taxa that may interfere with designated u ses of a
waterbody. The L inear V egetation S urvey (LVS) is a rapid assessment tool for evaluating the ecological

condition of streams based on vascular plants. Because many streams naturally have very little or no vegetation, interpretation of LVS data re quires that a minimum of two square meters ( 2 m 2 ) of macrophyte coverage be present throughout a 100 m eter stream reach. If there is <2 m 2 of vascular

3 The Department will evaluate those dominant species that individually constitute approximately 10% or more of the community.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

13 plant coverage present in a 100 m stream reach, there are no floral imbalances attributable to aquatic

p lants. LVS results from a stream are compared with LVS results compiled from the population of EPA

reference streams sampled by the Department as part of NNC development. The Department evaluated

LVS data from the EPA reference streams and found that if a site’s average C of C score is greater than or
equal to 2.5 (the 1 0 th percentile of the distribution) , the plant community composition may be considered to be part of the reference site distribution. Based on the Department’s experienc e in minimally disturbed streams and the types of plants associated with C of C scores greater than or equal

to 2.5 , this threshold was determined to be reasonable and protective.

The Department also analy zed the frequency of occurrence of FLEPCC exotics in the EPA reference

streams , and found that

, due to the influence of a few streams at the 90 th percentile, FLEPCC exotics made up approximately 40% of the total plant occurrences. Considering the somewhat limited number

of reference streams with vascular plants (nineteen) and the variability in the data , the Department

decided to set the FLEEPC threshold at the 80 th percentile of the distribution. Therefore, if the frequency of occurrence of FLEPCC exotics at a site is less than or equal to 25% of the total plant

occurrences (the 80 th percentile of the distribution) , the site may be considered to be part of the

reference site distribution.

Therefore, i f a site’s average C of C score is > 2.5 and the frequency of occurrence of FLEPPC exotic taxa

is < 2 5% of the total plant occurrences in two independent samples , this would indicate no imbalance of

flora. Because of the inherent temporal variability in aquatic plant communities, two temporally
independent LVS assessments should be conducted. If a strea m segment’s C of C score is < 2.5 and the frequency of occurrence of FLEPPC exotic taxa is > 25% during two consecutive, temporally independent samplings, the Department considers this as evidence that the NNC is not achieved. While variability of

LVS sam pling is typically low, i f the two samples have differing results in relation to the evidentiary threshold, then the preliminary analysis of this metric alone is inconclusive. Reviewing other data, information, or water quality/biology variables can help inform the reasons behind the differing results.
Additional sampling should be conducted until two temporally independent samplings either attain, or do not attain, the evidentiary thresholds, so a final decision can be made.



### LVS **Decision Key** 

1. Were environmental conditions associated with the LVS samples representative of the typical conditions of the system (e.g., flow between 10 th and 90 th percentile of long term discharge, light penetration characteristic of system, sampling location represen tative of waterbody segment, etc.).

1a. No. Collect additional LVS samples at representative locations and during representative conditions, and return to couplet 1. 1b. Yes, pr o ceed to couplet 2.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

14 2. Given that invasive exotic species can occur even in the absence of nutrient impacts and that
aquatic plant management practices can also affect LVS results, i s there evidence the LVS results can be linked to anthropogenic nutrient inputs ? 2a. Yes, proceed to couplet 3.

2b. No. The LVS results are inconclusive and other lines of floral evidence should be used.

3. Results of two temporally independent LVS samplings show that C of C score is > 2.5 and the frequency of occurrence of FLEPPC exotic taxa is < 25% ?

3a . Yes. Evidence that the waterbody achieves the nuisance macrophyte growth component of floral measures (other components must still be evaluated).

3b . No

. Evidence that the nutrient standard at 62

- 302.531(2)(c) is not achieved

.



### E VALUATING 

### A LGAL 

### B LOOMS 

### , C HLOROPHYLL A 

### , AND 

### P HYTOPLANKTON 

### T AXONOMIC 

### D ATA

A n annual geometric mean chlorophyll value of >20 μ g/L is used as an impairment threshold for both

lakes and streams in Chapter 62

- 303

, F.A.C. However, it is commonly understood that healthy la kes in Florida may be characterized by annual geometric mean chlorophylls up to 20 μg/L , while most healthy streams would be expected to have significantly lower chlorophyll a levels. While this impairment

threshold for streams was supported by an expert p anel of Florida scientists that helped the
Department develop the Impaired Waters Rule (IWR)

, neither the expert panel nor a review of stream
chlorophyll a literature was able to identify a stream chlorophyll a value below 20 μ g/L that definitively
did, or did not, support aquatic life uses

.

Th e range in “healthy” stream chlorophyll a values is due to a variety of site specific factors, such as system morphology, water residence time, and presence of lentic taxa may indicate a healthy aquatic

stream in a natural transition from a lotic to lentic system during the time period studied

. While the
Department compares the c hlorophyll a results from a stream to chlorophyll a results compiled from the population of minimally disturbed and healthy sites that was sampled by the Department as part of NNC
development , these site specific factors must also be taken into account

. If a stream exhibits annual geometric mean chlorophyll a concentrations between the mean observed at these minimally distur bed and healthy sites (2.0

- 2.1 μ g/L) and the associated 90 th percentile values (3.2

- 3.5 μ g/L), this is a clear
indication of no imbalance of flora. However, some Nutrient Benchmark streams and biologically healthy streams also exhibit annual geometric mean chlorophyll a values up to 17 μg/L and 19 μ g/L,
respectively

. Because the remaining distribution of observed annual geometric mean chlorophyll a values includes values approaching the IWR impairment threshold (and higher percentiles of the

distribution actually exceede d it), the Department chose to continue to utilize 20 μg/L as a chlorophyll impairment threshold. Therefore, s treams with annual average chloro phyll values between 3. 2 μg/L and

20 μ g/L are evaluated on a site specific basis , and factors such as water resid ence time, flow, color, climatological conditions, and size of the stream/river (i.e., stream order) are considered when chlorophyll a values are within this range. If a site has chlorophyll va lues within the 3. 2 μg/L to 20 μ g/L

range , the assessment is inconclusive until the Department documents a decision regarding whether chlorophyll a conditions reflect and imbalance in flora or not. When the Department determines that9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

15 the values indicate enrichment (e.g., are higher than function ally similar reference streams in the
region ) , the Department considers this evidence of imbalances in flora , and visa versa

.

The Department also assesses trends in chlorophyll a using a temporal trend test (a Mann’s one

- sided,

upper

- tail test for trend, w ith a 95% confidence interval) in conjunction with the chlorophyll a impairment threshold. The observation of a statistically significant increase in chlorophyll a in a stream is another line of evidence used by the Department to determine floral imbalanc es.

The Department also uses the presence of phytoplankton blooms as an indicator of floral imbalances. An unacceptable phytoplankton bloom would consist of a situation where an algal species, whose noxious characteristics or presence in sufficient number , biomass, or areal extent

, may reasonably be expected to prevent, or unreasonably interfere with, the designated use of a waterbody. The
Department evaluates the autecological information for the dominant bloom species (see references in Appendix B), in conjunction with the associated chlorophyll a when assessing imbalances of flora.



### Chlorophyll/Algal Bloom Decision Key

1. Were environmental conditions associated with the c hlorophyll samples representative of typical conditions for the system? (e.g., flow between 10 th and 90 th percentile of long term discharge, light penetration characteristic of system, sampling location representative of waterbody segment, etc.).

1a. No. Collect additional chlorophyll samples at representative locations and during representative conditions, and return to couplet 1. 1b. If Yes, see couplet 2.

2. Annual geometric mean chlorophyll < 3.2 ug/L?

2 a. Yes. Evidence that the waterbody achieves the chlorophyll a/algal bloom component of
floral measures (other components must still be evaluated).

2 b. If No , see couplet 3.

3. Annual geometric mean chlorophyll > 20 ug/L more than once in a three year period?

3 a. Yes. The narrative nutrient standard at 62

- 302.531(2)(c) is not achieved

. 3 b. No, annual geometric mean chlorophyll is between 3.2 and 20 ug/L , see couplet 4

.

4

. After considering site specific factors that affect chlorophyll concentrations , such as system morphology, water residence time, or consisten cy with other functionally similar reference sites

, can it be documented that t he chlorophyll a values represent a healthy well balanced phytoplankton community ?

4 a. Yes. Evidence that the waterbody achieves the chlorophyll a/algal bloom component of
floral measures.

4 b. No

. Evidence that the nutrient standard at 62

- 302.531(2)(c) is not achieved.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

16 4 c

. Inconclusive because of insufficient contemporaneous data from other functionally similar

reference sites. Waterbody will be placed on the Study List if either of the TN or TP

thresholds were exceeded

.



### F LORAL 

### M EASURES 

### S UMMARY

As described above, the Department deriv ed the floral thresholds that are used for this “weight of

evidence evaluation” using a distribution of a population of minimally disturbed Benchmark streams (the same streams used by EPA for their criteria development)

. T he thresholds summarized in Table 3

can be used when developing evidence supporting a Department conclusion regarding the balance of the floral community

. If a ll floral measures are achieved , a stream meets the floral component of a
healthy, well balanced aquatic system

, because it is wi thin the minimally disturbed Benchmark stream

condition

. However, if any one these floral measures indicates an imbalance, then the stream does not

attain the NNC

. Examples of this application of scientific reasoning are provided below.

Table 3. Floral measures summary. These values were based on the distribution of a population of
minimally disturbed Benchmark sites sampled by the Department as part of Numeric Nutrient Criteria
development (the same benchmark sites EPA used for their criteria)

.

Floral Metric Evidentiary Threshold of No Imbalances

LVS C of C Site a verage > 2.5

LVS FLEPPC Site a verage < 25%

RPS < 25 % rank 4

- 6 coverage 20 to 25 % rank 4

- 6 coverage, evaluate algal autoecological data

Chlorophyll < 20 ug/L; 3. 2 to 20 ug/L = site specific

Algal Community Composition ( Autecology ) No adverse shifts in dominant taxa



### F AUNAL 

### E VALUATION FOR 

### D ETERMINING 

### A CHIEVEMENT OF 

### NNC

Paragraph (2)( c) requires a demonstration that a stream has well

- balanced populations of flora and

either attains the Nutrient Thresholds or has healthy , well balanced fauna

. The presence of healthy fauna can be shown through the Stream Condition Index (SCI).

The SCI is a biological assessment procedure that measures the degree to which flowing fresh waters support a healthy, well

- balanced biological community, as indicated by benthic macroinvertebrates

. The
Department and EPA have concluded that a balanced faunal co mmunity is achieved if the average score of at least two temporally independent SCIs, performed at representative locations and times, is 40 or9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

17 higher, with neither of the two most r ecent SCI scores less than 35. To qualify as temporally
independent sampl es, each SCI must be conducted at least three months apart. SCIs collected at the same location less than three months apart will be considered one sample, with the mean value used to represent the sampling period.

Attainment of the SCI threshold is an in dication that the faunal community of the stream is not being adversely affected by nutrients to the extent that there is a loss in designated use. However, failure of

the SCI does not necessarily mean that the stressor causing the loss of designated use is nutrients. Evaluation of other factors, as indicated by the nutrient enrichment model in Figure 2 (including nutrient concentrations and floral communities) is useful information that could indicate nutrients are a factor.
While the stressor may not b e known, a failed SCI does indicate that fauna is not well

- balanced.

Alternatively, if the benchmark N utrient T hresholds in the Table in paragraph (2)(c) are attained, then the faunal community of the stream is presumed healthy with respect to nutrients, b ecause the benchmark thresholds were derived using nutrient levels in high quality, minimally disturbed streams. However, regardless of attainment of benchmark thresholds, if SCI results are available and a stressor identification study demonstrate that t he faunal community is not healthy as a result of nutrients, then

the stream will be listed as impaired for nutrients.

In summary, where the Nutrient Thresholds are exceeded but there are no imbalances in either aquatic flora (phytoplankton, periphyton, or vascular plants) or fauna (invertebrate community), the NNC is

achieved.



### E XAMPLES OF A 

### W EIGHT


### - OF


### - E VIDENCE 

### A PPROACH FOR 

### D ETERMINING 

### A CHIEVEMENT OF 

### N UTRIENT 

### C RITERIA

To evaluate whether a stream achieves the NNC , the investigator must compile water ch emistry data (e.g., Total Nitrogen [TN], Total Phosphorus [TP], chlorophyll a, and ancillary parameters such as color, turbidity, DO, pH, conductivity, and temperature, nitrate, etc.) and a minimum of two samples of each of

the follo wing: RPS, LVS , HA, and SCI. Taken together, these data are used as multiple lines of evidence to decide whether a stream is healthy, with acceptable levels of nutrients. Supporting parameters, such as color and nitrate, are used to help determine nutrient sources (e. g., high colored swamps have naturally elevated TN; very clear groundwater

- fed systems may have elevated nitrate). Examples of

how the Department evaluates these multiple lines of evidence are provided in Table 4 and discussed

below.

In Stream 1, although the RPS data showed a pulse of periphyton (which consisted of the generally non

problematic alga, Oedogonium), it was not persistent, meaning the RPS results were acceptable. Because no plants were found in the water, the LVS results indicated no imbalan ces. However, an increasing trend was observed in annual chlorophyll a (using a Mann’s one

- sided, upper

- tail test for trend, with a 95% confidence interval), and the chlorophyll values exceeded those typically observed in
healthy streams. Although the SC I score was currently acceptable and habitat was not limiting, the
Department concluded that the chlorophyll issue, following the conceptual model in Figure 2 , was sufficient to judge that this stream has impaired flora. It is likely that the increased or ganic matter9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

18 enrichment associated with the excess phytoplankton (as indicated by the chlorophyll) would eventually

lead to faunal imbalances.

Stream 2 was characterized by significant algal smothering, as demonstrated through the RPS results.

Taxonomic i dentification showed the algae community to be dominated by Lyngbya, a known nuisance species. Although the vascular plant community, as assessed using the LVS, was within the range of reference streams, and chlorophyll a was non

- problematic, the algal gr owth resulted in aquatic habitat smothering (a component of the HA), which likely led to the failing SCI score. The Department concluded that the RPS results, coupled with a poor habitat smothering score, was evidence that stream 2 has impaired flora, whi ch in turn caused impaired fauna. These responses are consistent with the

nutrient enrichment model.

Although periphyton and chlorophyll a were not issues in stream 3, the HA and LVS results showed that the invasive exotic vascular plant, Hydrilla, was ex cessively abundant, leading to imbalances of flora. An

increase in Hydrilla abundance was associated with reduced substrate diversity and failing SCI scores, meaning the elevated nutrient levels were associated with imbalances in flora and fauna, consiste nt with the nutrient enrichment model. This situation is complicated because invasive exotic plants can be observed even without nutrient enrichment. It is important to review other information, including the levels of nutrients in the waterbody that cou ld contribute to species proliferation. In this circumstance,
the Department concluded that excess anthropogenic nutrients exacerbated the floral community imbalances as evidenced by the LVS results.

Stream 4 is a minimally disturbed Benchmark stream with TN and TP levels at the upper 98 th percentile of the data distribution used to establish the regional Nutrient Threshold. The RPS and SCI indicated normal, healthy conditions. No plants were observed in the water, meaning the LVS was acceptable.

Howeve r, an annual chlorophyll a value of 10.5 μg/L was observed in one year, which is between the 3.5 to 20 μg/L range, and site specific information was subsequently evaluated. In this case, a drought year
was associated with the moderately elevated chlorophy ll, and other nearby reference streams also
exhibited similar increases in chlorophyll. The algae associated with the elevated chlorophyll included
the diatoms, Achnanthes exiguum

, Anomoeneis vitrea , and Cymbella minuta , which are normally found

in refe rence streams. The Department concluded that the drought conditions were associated with the chlorophyll value, and that this level was within the variability of the reference site data. Because the SCI was healthy and there were no other indicators of nu trient issues, the Department concluded that nutrient levels associated with Stream 4 are acceptable and the NNC is achieved.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

19 Table 4 . Examples of RPS, LVS, chlorophyll a , HA, and SCI data used to illustrate a multiple lines

- of

evidence approach used by the Department for determining whether or not a stream exhibits imbalances of flora or fauna. In these examples, TP, TN, or both nutrients exceed the regional Nutrient

Thr eshold values

.

Measure Sample

# Stream 1

1 2 3 4 5 6

RPS (% Rank 4

- 6) 1 21 45 4 8 3 26

2 2 65 7 15 0 37

LVS Avg. C

of C 1 No
vegetation 2.6 1.9 No
vegetation 3.5 1.8

2 No
vegetation 3.2 0.5 No
vegetation 4.2 2.4

FLEPPC % 1 No
vegetation 12 45 No
vegetation 0 31

2 No
vegetation 4 74 No
vegetation 0 26

Chlorophyll (μg/L

as annual
geometric mean) Year 1 17.2 1.1 Non

Detect 10 .5 3.5 1.3

Year 2 22.1 2.1 Non

Detect 1.2 4.1 1.1

Increasing Chlorophyll Trend Yes No No No No No

Habitat

Assessment 1 121 109 105 133 81 110

2 113 102 98 126 77 107

SCI 1 45 44 39 67 22 42

2 39 33 29 58 31 39

1 In these examples, TP, TN, or both nutrients exceed the regional Nutrient Threshold values. No vegetation = No
plants in water, therefore, LVS results indicate no imbalance

.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

20 Floral measures at stream 5 were non

- problematic, despite nutrient concentrations that exceeded the regional t hreshold values. No primary or secondary nutrient responses, as described by the nutrient enrichment model, were observed, but the SCI indicated impaired fauna. The SCI results, combined with higher levels of nutrients, lead to the conclusion that the NN C is not achieved. In this case however, habitat assessment results indicated artificial channelization, poor substrate diversity and availability, and a compromised riparian buffer zone. Observations also indicated extensive hydrologic

modifications in the drainage basin. These habitat and hydrologic factors were evaluated as part of a
TMDL process, prior to initiating a TMDL. After an evaluation of all stressors (through a stressor identification study), habitat and hydrologic improvements were found to be the stressors affecting
stream health, and not nutrient concentrations. The Department would then evaluate this stream under a site specific structure described in Rule 62

- 302.531, F.A.C.

In stream 6, both the RPS and LVS results suggested early war nings of nutrient enrichment, with persistent periphyton coverage and changes in the vascular plant community, even though chlorophyll a and SCI results were acceptable. The periphyton community was dominated by Vaucheria , a known nuisance species, while the vascular plants, Alternanthera philoxeroides and Panicum repens (two FLEPPC exotics), were moderately abundant. Habitat assessment results indicated moderate
smothering by the periphyton and a reduction in substrate diversity associated with the exoti c plant growth. The Department concluded that this was sufficient evidence of floral imbalances, which if allowed to continue without intervention, would also result in faunal imbalances, as predicted by the

nutrient e nrichment model

.



### S TREAM 

### S AMPLING 

### L OCA TIONS AND 

### O THER 

### E NVIRONMENTAL 

### C ONSIDERATIONS

When conducting nutrient studies, it is important to confirm that sampling locations and other environmental conditions (canopy cover, habitat, water depth and flow, etc.) are representative of the
system and th at water quality data are collected in the same homogeneous waterbody segment as the biological monitoring stations. Establishing spatial relationships between the water quality data and biological health data is dependent upon the homogeneity of the stre am or stream segment. In stream segments that have homogeneous nutrient concentrations, at least one biological station (for floral and faunal measures) should be sampled during two temporally independent time periods. If a stream is not homogeneous with regard to nutrients, the stream should be divided into homogeneous units (segments), and the biological evaluation conducted for each segment.

The following elements should be addressed when sampling to evaluate attainment of the NNC in paragraph 62

- 302. 530(47)(b), F.A.C., and to affirmatively demonstrate that nutrients are not adversely affecting flora and fauna:

1. Biological sampling locations should be selected to reduce or eliminate the effects of confounding variables. Sampling should be conducted in areas where other physical factors, especially habitat and hydrology, do not limit biological expectations. Efforts should be taken to

establish sites in stream reaches (where possible) with minimal hydrological modifications and
optimal habitat, includin g adequate substrate diversity and availability, intact stream9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

21 morphology (minimal or no artificial channelization), adequate velocity and flow, and optimal riparian buffer zones (see the Department’s SOP FS 3000 for Habitat Assessment procedures).

Sites should also be selected where light penetration through the tree canopy is representative of the stream segment (i.e., avoid bridge or powerline crossings where the canopy has been artificially changed in a relatively small area). While care should be take n to minimize confounding factors, sampling locations should be sited within stream segments that are representative of typical conditions. Additional information on controlling for the effects of confounding factors is presented in the SCI Primer.

2. A l l biological sampling should be conducted consistent with the Department’s Standard Operating Procedures (SOPs) and SCI Primer.

3. Water quality stations should be located where there is a clear relationship between the nutrient regime and the system’s bio logical health, as assessed using either the floral or faunal
measures. For streams, this means that site

- specific information should be relied upon to

ensure that the biological sampling site (s) provide response information representative of
potential effects caused by nutrients in the system

. Therefore , site

- specific confounding factors and the potential for downstream expression of nutrients should be considered when determining sampling locations. For example, if a discharge or tributary significan tly influences
the nutrient concentrations in an area associated with the biological collection site, then data from stations located upstream of that discharge should not be used for establishing the ambient values associated with the biological data.

4. Unless a very large data set has been established, sampling during extreme climatic or hydrologic conditions, such as floods, droughts, or hurricanes, should be avoided.



## Nutrient Criteria in Estuaries

Rule 62

- 302.532 , F.A.C., contains estuary

- specific nu meric interpretations of the NNC in paragraph 62

- 302.530(47)(b), F.A.C., for estuaries along the Southwest Coast (roughly from Tampa Bay to Miami and the Florida Keys) . These criteria were developed individually for each estuary segment to protect

recreati on and a healthy, well

- balanced population of fish and wildlife , and are hierarchy 1 interpretations pursuant to paragraph 62

- 302.531(2)(a), F.A.C . The concentration

- based estuary
interpretations are open water, area

- wide averages.



# Decision Matrix and Ex amples for Implementing the Hierarchical Process

The Department has developed a decision matrix for assessing the stream nutrient thresholds in Rule

62

- 302.531(2)(c), F.A.C. ( Table 5) and e xamples that illustrate how Florida’s numeric nutrient criteria are9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

22 assessed using the hierarchical framework. For both the matrix and the examples, the following
assessment categories 4 , were used :

• 1

- Attaining all designated uses;

• 2

- Attaining some designated uses and insufficient or no information or data are present to determine if remaining uses are attained;

• 3A

- No data and information are present to determine if any designated use is attained;

• 3B

- Some data and information are present but not enough to determine if any designated use
is attained;

• 3C

- Potentially impaired, exceedances meet the requirements of the Impaired Waters Rule for
placement on the Planning List;

• 4A

- TMDL developed, additional sampling would be used to gauge success of TMDL;

• 4B

- Impaired but TMDL not needed (Reasonable Assurance activities underway);

• 4C

- Fails criteria but due to natural condition. In this case, the generic criteria are inappropriate, and development of a “natural background” (Type I) SSAC may be warranted;

• 4D

- Fails criteria but causative pollutant has not been determined, therefore, a pollutant cause

effect study is needed;

• 4E

- Impaired, but restoration ongoing; and

• 5

- Impaired. Fails criteria and causative pollutant identified.

4 The assessment categories ar e the same as those in the Department’s Integrated Report

.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

23 Table 5. Decision m atrix for a ssessment of s tream n utrient t h resholds in Rule 62

- 302.531(2)(c), F.A.C. Reasonable Assurance is demonstrated for near

- field effects when the receiving streams is shown to “Attain .531(2)(c)”. This table does not address increasing trends in nutrien t concentrations, and increasing

tre nds in nutrient causal or response variables can result in placement of waterbodies on the Study List or Verified List [ 303(d) List ] independent of the

conclusion articulated in this table. Assessing Stream Biological Health using the SCI pursuant to the biological health assessment provisions of the IWR is conducted concurrently to the Nutrient Assessments described in this table as follows: If only 1 SCI is available and it is <35 , the water is placed on the Planning List, Cat. 3c for biology; If only 1 SCI is available and it is >35 , the water is placed in Cat. 3b for biology; If the 2 most recent SCIs have 1 sample <35 or

the average is <40 , the water is placed on the Study List, Cat. 4d for biology to cond uct a Stressor Identification (SI) study to determine causative pollutant(s).

If the SI study determines a pollutant is responsible for the biological impairment , the water is placed on the Verified List, Cat. 5. If the SI study determines

nutrients are responsible (even if nutrient thresholds are attained), then 62

- 302.531(2)(c) is Not Attained , and the water is placed on the Verified List, Cat. 5.

If the 2 most recent SCIs average 40 or higher, and neither is <35 , then the water is placed in Cat. 2.

Attains Nutrient Thresholds for Both TN and TP (3 Years of Data) Nutrient Threshold Attainment Inconclusive for Either

TN or TP (< 3 Years of Data) At Least One Nutrient Threshold Not Attained (3 Years of Data)

SCI Attains (2 Samples) SCI
Inconclusive ( <2 Samples) SCI Not
Attained

(1 or 2 Samples) SCI Attains SCI
Inconclusive SCI Not Attained SCI Attains SCI Inconclusive SCI Not Attained

Attains
Floral

Measures (2 Sampling

Events) Attains .531(2)(c)

Cat. 2 Attains .531(2)(c)

Cat. 2 Attains .531(2)(c)

Cat. 2 Attains .531(2)(c)

Cat. 2 Cannot
Conclude .531(2)(c)

Assessment

Cat. 3b Cannot Conclude .531(2)(c)

Assessment

Cat. 3b Attains .531(2)(c)

Cat. 2 Cannot Conclude .531(2)(c)

Assessment

Cat. 4d (Study &

303(d) List) .531(2)(c) Not

At tained

Cat. 5 (Verified &

303(d) List)

Floral

Measures
Inconclusive (<2 Sampling

Events) Cannot
Conclude .531(2)(c)

Assessment

Cat. 3b or 3c(Planning List) Cannot
Conclude .531(2)(c)

Assessment

Cat. 3b or 3c(Planning List) Cannot
Conclude .531(2)(c)

Assessment

Cat. 3b or 3c(Planning List) Cannot
Conclude .53 1(2)(c)

Assessment

Cat. 3b or 3c(Planning List) Cannot
Conclude .531(2)(c)

Assessment

Cat. 3b or 3c(Planning List) Cannot Conclude .531(2)(c)

Assessmen t

Cat. 4d (Study &

303(d) List) Cannot

Con clude

- .531(2)(c)

Assessment

Cat. 4d (Study &

303(d) List) Cannot Conclude .531(2)(c)

Assessment

Cat. 4d (Study &

303(d) List) . 531(2)(c) Not

Attained

Cat. 5 (Verified & 303(d) List)

Any One

Floral

Measure Not

Attained (2 Sampling

Events) .531(2)(c) Not
Attained

Cat. 5 (Verified & 303(d) List) .531(2)(c) Not
Attained

Cat. 5 (Verified & 303(d) List) .531(2)(c) Not
Attained

Cat 5 (Verified & 303(d) List) .531(2)(c) Not
Attained

Cat. 5 (Verified & 303(d) List) .531(2)(c) Not
Attained

Cat/ 5 (Verified & 303(d) List) .531(2)(c) Not
Attained

Cat. 5 (Verified &

303(d) List) .531(2)(c) Not
Attained

Cat. 5 (Verified &

303(d) List) .531(2)(c) Not
Attained

Cat. 5 (Verified &

303(d) List) .531(2)(c) Not
Attained

Cat. 5 (Verified &

303(d) List)9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

24 

## Hierarchies 1 and 2

E XAMPLES OF 

### H IERARCHY 

### 1

Hierarchy 1

– TMDLs, nutrient SSACs, Level II WQBELs and other Department approved actions such as

RA plans are the applicable numeric interpretation of the narrative nutrient criteria

, subject to EPA

review

.

• Freshwater Portions of the Lower St. Johns River

o Status : Has a nutrient TMDL for TN and TP

.

o Action required : Assessed as category 4a. No additional action required. Implement

TMDL and BMAP as planned.

• Marine Portion of the Lower St. Johns River

o Status: Has a TMDL for TN.

o Action required : Assessed as category 4a. Implement TN TMDL and BMAP as planned. Continue to implement the narrative for TP until applicable NNC adopted.



### E XAMPLES OF 

### H IERARCHY 

### 2

Hierarchy 2

– Numeric interpretation of the narrative criterion based on an established, quantifiable understanding of the stressor

- response relationship between nutrient concentrations and biological imbalance. Currently this relationship has been determined only f or freshwater springs and lakes.

• Lithia Springs

o Status : Has no site specific interpretation, but exceeds the springs

- specific stressor

response based nitrate criterion of 0.35 mg/ L

.

o Action required : List the spring as Verified Impaired (category 5) and ta ke action to achieve the 0.35 mg/ L nitrate criteri on . A Basin Management Action Plan (BMAP) will
be developed that addresses sources of nitrogen in the springshed.

• Silver Springs

o Status : Has no site specific interpretation, but exceeds the springs

- specifi c stressor

response based nitrate criteri on of 0.35 mg/ L

.

o Action required : List the spring as Verified Impaired (category 5) and take action to achieve the 0.35 mg/ L limit as nutrient criteri on . Silver Springs has a TMDL scheduled to be complete in 2012 , which will move it to Hierarchy 1. A BMAP will be developed that addresses sources of nitrogen in the springshed.9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

25 • Lake Harney

o Status : Has no site specific interpretation. Meets the lakes nutrient and chlorophyll a

criteria and Lake Vegetation Index results indicate a healthy plant community

.

o Action required : Not impaired (category 2)

, and no additional action required.

• Lake Gibson

o Status : Has no site specific interpretation. Meets the lakes chlorophyll a criteria

, but exceeds the upper range of the TP criterion

.

o Action required : List the lake as Verified Impaired (category 5) and develop nutrient TMDL, which will serve as primary site specific nutrient interpretation. May also be a candidate for a SSAC since the chlorophyll a criteria is met (provided vascular plant community, as measured by the LVI, is also healthy)

.

• Lake Istokpoga

o Status : Has no site specific interpretation. Exceeds the lakes chlorophyll a criteri on more than once in a three year period.

o Action requi r ed : Place on Ver ified List (category 5) for nutrient impairment and develop nutrient TMDL, which will serve as primary site specific nutrient interpretation.



## Hierarchy 3

Hierarchy 3

– As described in Table 5, the n umeric interpretation of the narrative criteri on is based on a

combination of reference

- based nutrient thresholds and biological information (currently limited to streams, excluding intermittent systems

, canals/ditches , and South Florida region ) 5

. Streams can fall

into the following main categories at the end of the Phase 2 assessment of the Watershed Management Cycle :

a. Waters that meet the nutrient thresholds and have sufficient data to document they have
healthy flora . These waters are deemed to attain the NNC (category 2)

.

b. Waters that exceed the nutrient thresholds, but are biologically healthy (both flora and fauna)

. These waters are deemed to attain the NNC (category 2)

.

c. Waters that exceed the nutrient thresholds, but there is insufficient information to fully assess
the biological health of the stream. These waters are placed on the Study List (category 4d)

.

5 Streams are also independently assessed using the nutrient impairment thresholds in the IWR (20 ug/L chlorophyll a , for example).9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

26 d. Waters that meet the nutrient thresholds, but there is insufficient information to assess the floral community. These waters will be placed on the Planning List for additional study (category 3c)

.

e. Waters that meet the nutrient thresholds, but are not biologically healthy . These waters will be placed on the Study List to determine the causative pollutant (category 4d) . If the causative
pollutant is determined to be a nutrient, the waterbody will b e listed on the Verified List (category 5) for nutrient impairment even if the nutrient thresholds are attained.

f. Waters that exhibit an imbalance of flora, or exceed the nutrient thresholds and are not
biologically healthy (fauna)

. These water s are plac ed on the Verified List (category 5)

.

For category “ f ” waters above where nutrients are identified to be a causati ve pollutant , the Department will develop a site specific response (such as a TMDL), at which point the waterbody would
fall under “Hierarchy 1” after formal Department action (with subsequent EPA approval)

.



### E XAMPLES OF 

### H I ERARCHY 

### 3

 Waters achieving the nutrient thresholds that are also biologically healthy.

• Little Manatee River

o Status : Has no primary site specific interpretation, but satisfies r eference

- based nutrient thresholds and is determined to have healthy biology (both flora and fauna)

.

o Action required : No additional action required. Place assessed condition in category 2

of the I ntegrated R eport.

 Waters that exceed the nutrient thresholds, but are biologically healthy.

• Econfina River

o Status : Has no primary site specific interpretation. Exceeds reference

- based nutrient thresholds due to natural swamp inputs, but has sufficient floral and faunal in formation
to determine that it is biologically healthy.

o Action required : Achieves NNC

. No additional action required. Place assessed condition in category 2 of the integrated report.

• Aucilla River

o Status : Has no primary site specific interpretation. Exceeds reference

- based nutrient thresholds due to natural swamp inputs, has evidence of healthy fauna (SCI), but
requires further study to gather additional required floral information.

o Action required : Place on Study List to gather sufficient floral data to make final

determination. Place in Category 4d.9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

27  Waters that meet the nutrient thresholds, but are not biologically healthy based on either failing

SCIs or floral measures

. Waters with failing SCIs are placed on the Study List to identify stressor/causative factor(s) , or are placed directly on the Verified List if stressor/ causative

information is available

. Waters with evidence of imbalance based on floral measures are placed
directly on the Verifi ed List.

• Weeki Wachee River

o Status : Has no primary site specific interpretation. Achieves reference

- based nutrient thresholds, but is determined not to be biologically healthy due to failing SCI and excess
algal mats

.

o Action required: Because floral information is available, bypass Study List and p lace on Verified List for nutrient impairment (due to excess algal mats) and develop nutrient
TMDL, which can serve as primary and independent site specific nutrient interpretation.
The Department will prov ide documentation for the record to demonstrate how the biological data indicate an imbalance in flora and/or fauna. Place assessed condition in category 5 of the I ntegrated R eport.

• Huckleberry Creek

o Status : Has no primary site specific interpretation. A chieves reference

- based nutrient thresholds, but is determined not to be biologically healthy due to excess nuisance plant
growth.

o Action required: Because floral information is available, bypass Study List and place on Verified List for nutrient impairme nt (due to excess nuisance plant growth) and develop nutrient TMDL, which will serve as primary site specific nutrient interpretation. The
Department will provide documentation for the record to demonstrate how the
biological data indicate an imbalance in flora and/or fauna. Place assessed condition in category 5 of the I ntegrated R eport.

 Waters that meet the nutrient thresholds, but do not have biological data ( floral measures )

.

• Halls Branch

o Status : Has no primary site specific interpretation. Achieves reference

- based nutrient
thresholds, but no biological data are available.

o Action required: Place on Planning List to gather sufficient floral data to make final
determination. Place in Category 3 b.

 Waters that exceed the nutrient thresholds and are not biologically healthy.

• New River

o Status : Has no primary site specific interpretation. Exceeds reference

- based total
phosphorus threshold and is not biologically healthy based on most recent SCI resu lt s

.9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

28 Action required: Place on Verified List for nutrient impairment and develop nutrient TMDL, which will serve as primary site specific nutrient interpretation. The water could be delisted for nutrients if a Stressor Identification Study determines tha t factors other than nutrients are responsible for the degradation. Place assessed condition in category

5 of the I ntegrated Report.



## Waterbody Types and Cases with Insufficient Information

In aquatic systems where th e Department does not have sufficient information to accurately interpret

the NNC , such as Class III wetlands, Class III flowing waters in South Florida, and Class III intermittent or highly altered streams, the narrative will continue to apply

. The Department will continue to re ly on
existing assessment provisions contained in the Impaired Waters Rule to list these waterbodies. T he Department will numerically interpret the narrative criteri on as the information is developed.



## Other Components of NNC

• Attainment of the narrative criterion is a ssess ed over a spatial area consistent with its

derivation. For Tier 1 numeric interpretations based on paragraph 62

- 302.531(2)(a), F.A.C., the spatial application of the numeric interpretation is as defined in the

associated order or rule. For lakes, the numeric interpretation shall be applied as a lake

wide or lake segment

- wide average. Except for extremely large lakes (e.g., Lake Okeechobee, which has been subdivided), the lakes criteria apply to lakewide averages. For spring vents, th e numeric interpretation shall be applied in the surface water at or above the spring vent. For streams, the spatial application of the numeric interpretation
shall be determined by relative stream homogeneity and shall be applied to waterbody

segments or aggregations of segments as determined by the site

- specific

considerations. The stream nutrient thresholds were derived though a distributional analysis of data from homogeneous reference stream segments , with the spatial extent of each stream segment ty pically measuring approximately five linear miles

. Two or more stream segments may be combined if the nutrient data are homogeneous, which is evaluated through routine statistical tests, such as Analysis of Variance or Student’s t

test

, and if the results show that the segments are not significantly different at the 90 percent confidence level

. Data will be transformed ( e.g ., log) prior to statistical analysis if the data are not normally distributed.

• Except for d ata used to establish histor ic chlorophyll a levels, chlorophyll a data shall be measured according to the Department document titled “Applicability of Chlorophyll a Methods” (DEP

- SAS

- 002/10), and be corrected for, or free from, the interference of
phaeophytin.

• If there is more than one hierarchy 1 interpretation for a given waterbody, the most recently adopted interpretation controls

.9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

29 

## NNC and Protection of Downstream Waters

Protection of downstream waters is required in the new nutrient standards by the statement, “The loading of nu trients from a waterbody shall be limited as necessary to provide for the attainment and maintenance of water quality standards in downstream waters.” This provision is implemented by the Department by:

• Using models to a llocat e to upstream watersheds when establishing the TMDL for the downstream waterbody ;

• Requiring dischargers

, at the time of permit issuance

, to provide reasonable assurance that their effluent does not cause or contribute to nutrient impairments in the receiving waterbody and downstream waterbodies ; and

• Identifying trends in nutrient concentrations in all waters, including downstream waters

, during the assessment cycle

.



### W ATER 

### Q UALITY 

### M ODELING

A watershed model , such as WASP or LSPC, can be applied to ensure that the narrative downstrea m water quality standard is achieved when developing and allocating TMDLs and when developing nutrient

SSACs

. T he model can be used to ensure that “ loading of nutrients from a waterbody shall be limited as necessary to provide for the attainment and maint enance of water quality standards in downstream

waters.”



### I SSUANCE OF 

### NPDES P ERMITS

A n upstream regulatory decision, such as a permit issuance, might be executed by evaluating the

nutrient conditions of near

- field and downstream waterbodies. E valuating near

- field conditions was

described earlier . Do wnstream evaluations can be conducted similarly. For example, if a downstream lake is currently attaining its nutrient standards, then current conditions in the upstream waters provide

for that attainment co ndition ( i.e

., loading of nutrients from the waterbody would be limited at current conditions to provide for the continued attainment and maintenance of water quality standards in

downstream waters ) . However, a L evel II WQBEL will be needed to evaluate the impacts on downstream waters if the facility requests an increase in their permitted load

. If the facility does not request an increase in its permitted load but is discharging significantly below its permitted capacity, the

WQBE L that was the basis for the current permit limits is reviewed to ensure that it is still a valid interpretation of the narrative nutrient criterion.

If a downstream waterbody is not attaining nutrient standards, the permit could not be issued until

reaso nable assurance was provided that the facility’s discharge was not contributing to the impairment. This can be done in response to a Department adopted TMDL , or through independent modeling conducted in the watershed. Once modeling is conducted, the resu lts of that modeling can be used to

ensure that loading of nutrients from the upstream waterbody is limited as necessary to provide for the attainment and maintenance of the water quality standards of downstream waters.9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

30 

### E VALUATION OF 

### T RENDS

E ven if both upstream and downstream waters are currently attaining nutrient standards or in situations

where information for downstream waters is not available , the Department’s nutrient standards include

an evaluation of trends to ensure that conditions are not incr eased in a manner that could result in
impairment downstream. Pursuant to Chapter 62

- 303, F.A.C., t he Department assesses whether there is

a n adverse trend in nutrients ( nitrate

- nitrite, TN or TP) or a nutrient response variable (chlorophyll a )

and if the waterbody is expected to become impaired. If statistically significant adverse trends are present in causal variables , then the waterbody will initially be placed on the Planning List 6 of potentially
impaired waters so that a more rigorous statistical analysis can be conducted. If statistically significant adverse trends are present in causal variables after control ling for confounding variables and the waterbody is expected to become impaired within 10 years , then the waterbody will be placed on the
Study List and the Department will develop a site specific interpretation of the NNC for the waterbody. This interpretation would likely be a nutrient SSAC, and would be implemented and ap plied to upstream waters feeding the waterbody including in NPDES permits for upstream dischargers as described in the

section titled “ WQBEL Procedures for Each Tier of the Hierarchy .”

If statistically significant adverse trends are present in response va riables (after control ling for confounding variables) and the waterbody is expected to become impaired within 5 years , then the waterbody will be placed on the Verified List for nutrient impairment, pursuant to subsection 62

- 303.450(4), F.A.C. , and a TMDL will be developed, which will be a site

- specific interpretation of the NNC

and set levels/allocations to upstream waterbodies

. The TMDL , which would include wasteload allocations for point sources and load allocations for nonpoint sources, would be implem ented in NPDES permits for upstream dischargers as described in the section titled “ WQBEL Procedures for Each Tier of the Hierarchy ”, and any needed reductions in nonpoint sources would be implemented via the BMAP for
the TMDL, which is enforceable for non point sources.

When evaluating changes over time, c onfounding, or exogenous variables, such as natural random phenomena ( e.g ., rainfall, flow, and temperature) often have considerable influence on the response variable in question ( e.g ., nutrient concentra tion or chlorophyll ). By statistically accounting for exogenous influences , the background variability is reduced so that any trend present can be better

observed. Th is process involves standard statistical model ing, such as least squares regression or

LOca lly WEighted Scatterplot Smoothing ( LOWESS ) analysis , with a subsequent analysis for increasing

trend in the residuals

. To be considered statistically significant, the p value associated with the residuals

trend analysis sh all be less than 0. 05 . If t he slope of the projected trend line is expected to exceed either a nutrient or nutrient response variable endpoint within 10 or 5 y ears ( and if there is evidence of
anthropogenic nutrient enrichment ), the waterbody shall be placed on the Study or Verified List, respectively.

T his process involves two steps. First, i f an increasing trend is determined for nutrients, the Department

an a lyzes the statistical relationship between nutrients and the a ssociated nutrient response variable to

6 See the Section titled “Implementing the NNC Revisions to the I mpaired Water Rule (Chapter 62

- 303, F.A.C)” for a full description of the Planning, Study and Verified Lists.9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

31 determine the level of nutrients at which imbalance would occur. Next, the Department would analyze the slope of the trend to determine if the response variable would exceed the level associated with

imbalance within 5 or 10 years, given the trend observed in nutrients.

To i llustrate this concept, data were analyzed from Station 3566 in the Weeki Wachee River. Based on flow adjusted residuals analysis, the Weeki Wachee River exhibits a statistically significant nitrate

- nitrite

trend. Although there is an apparent trend in t he raw data ( Figure 4 ), the influence of flow ( Figure 5 ) was taken into account to determine the statistical validity of the trend. Note that the residuals plot ( Figure 6 ) shows a more striking trend over time, and that the results are significant (p

- valu e is < 0.001) with an increasing slope of 0.03 mg/L per month.

Figure 4. Nitrate concentrations in Weeki Wachee River over time.

Figure 5 . Weeki Wachee river flow (CFS) from 1999 to 2011. COLLECTION.DATENitrate+Nitrite, Total (as N)

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 20110.40.50.60.70.80.9 3566

COLLECTION.DATEFLOW (cfs)

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011120140160180200220240 35669- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

32 Figure 6 . Weeki Wachee residuals over time ( derived from the flow vs. nitrate regression), highlighting the trend during the years from 1999 to 2003.

These data may be used to demonstrate how the Department would implement the adverse trend test, which is designed to determine if the water will be impaired within 5 years ( for the Verified List), taking into consideration the current concentrations of nutrients or nutrient response variables and the slope

of the trend. For example purposes, suppose the Department had adopted the adverse trend test prior to 1999, and suppose that site

- specific algal responses in the Weeki Wachee River had led to the

conclusion that a nitrate level of 0.71 would lead to failure s of the Rapid Periphyton Survey. Based on the significant trend in the residuals plot, the Department would have estimated that this concentration of nitrate (0.71 mg/L ) would be exceeded in 2003, allowing the Department to place the water on the

verifi ed list in 1999 and take action to reduce nitrate levels prior to the actual impairment occurring.

While this example focuses on the trends in nutrients in the Weeki Wachee River, it is important to note

that downstream waters would also be assessed for trends. Any TMDL developed to address the increasing trend in nitrate levels would, in addition to protecting the Weeki Wachee River, have the added benefit of protecting downstream waters even if there were no observable increases in nutrients or nutrient response variable in the downstream waters.



### T REND 

### T EST 

### S UMMARY

Because the trend test applies to lakes and estuaries, as well as the streams that feed them, it provides an enhanced method to assure that downstream waters are fully protected. In addition to the above example, if an adverse trend in TP were observed in a downstream lake or estuary, a site specific

criterion would be developed for the waterbody prior to it becoming impaired

, and this action would

establish TP expectations for upstream water s at a level that would prevent the lake or estuary from exceeding the app licable nutrient criteria. The adverse trend test , which is linked to the numeric criteria necessary to protect recreation and healthy, well balanced aquatic communities, allows for Hierarchy 1 COLLECTION.DATEResidual

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 20110.5 0.6 0.7 0.8 0.9 35669

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

33 site

- specific and highly accurate downstream protection values to be developed prior to the downstream waters from becoming impaired.



## Discussion of TMDLs as NNC

• Only State

- adopted nutrient TMDLs are eligible as site

- specific interpretations of the

NNC

.

• To be eligible, the nutrient TMDLs must be based upon prevention of imbalances of flora or fauna ( paragraph 62

- 302.530 (47)(b), F

. A

. C .) . Nutrient TMDLs that address dissolved oxygen (DO) impairment ( paragraph 62

- 302.530 (47)(a), F

. A

. C

. ) would also be eligible if nutrients were identified as a causative pollutant and the TMDL demonstrated that it would also prevent an imbalance of natural populations of flora and fauna. As an
example, surplus anthropogenic nutrients could be shown to generate excess plant biomass (periphyton, phytoplankton, or vascular plants), which could by themselves constitute an imbalance in flora or result in habitat smothering (e.g., excess periphyton

ac cumulation), food web alteration (e.g., dominance of taxa that thrive in nutrient enriched conditions), or low DO (from decomposition or respiration of excess plant biomass), etc., that results in imbalances in fauna, as reflected by failing SCI scores or

an other meaningful biological endpoint (e.g., decline in seagrass coverage, reduced transparency, etc.). If the TMDL is written to prevent this cycle and then achieve DO, it could be eligible as the numeric interpretation of paragraph 62

- 302.530 (47)(b), F.A.C.

S tanda r d statistical tests, such as regression or other appropriate empirical or

deterministic model s , are used to demonstrate a “predictable and measurable” DO
response to nutrients

. The p value associated with the regression or other statistical

model should be less than 0.05 and the variability in DO explained by nutrients should be suff icient ( e.g ., r 2 > 0. 2 5) to expect that nutrient reductions would lead to
improvements in DO and maintain or restore a healthy, well balanced bi ological
community

.

• Many TMDLs are expressed as loads instead of concentrations, but the loads do not have to be translated into concentrations to be deemed the numeric interpretation of

the NNC

.

• TMDLs may be modified based on new data, new science, or di fferent targeted endpoints (such as DO). When TMDLs are modified and re

- adopted, they become the new interpretation of the NNC

.

• Future TMDL rules may include a response target (chlorophyll a, for example) designed to implement the NNC . Scientific informa tion relating to the response target and the basis for existing TMDLs is presented in the TMDL reports ; and this information can be

used to establish a site

- specific listing threshold for nutrient impairment pursuant to

Rule 62

- 303.450, F.A.C.9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

34 • TMDLs may be written to achieve numeric nutrient values established in Chapter 62

- 30 2 , F.A.C., (lakes or springs), or alternatively, to achieve conditions necessary to protect the NNC . If written to achieve the NNC , the site

- specific thresholds used for the

TMDL wo uld become the numeric interpretation of the narrative pursuant to “1” of the
hierarchy.

• After Rule 62

- 302.531, F.A.C.

, becomes effective, subsequently adopted h ierarchy 1

nutrient TMDLs must be publically noticed as new numeric interpretations of the

narrative criteri on and as changes to state water quality standards

. Consistent with the
CWA, these site

- specific interpretations will be submitted to EPA for review.



## Discussion of Site Specific Alternative Criteria as NNC

• The restriction on establishin g a Type II SSAC for nutrients pursuant to subsection 62

- 303.800(2), F.A.C., was eliminated in the revised rule adopted in December 2011.

• A new SSAC provision for a “Type III SSAC” was also adopted to allow a predictable approach to developing nutrient SSA Cs. The rule language provides clear expectations on the water quality and biological data needed to characterize existing nutrient concentrations and aquatic health, but the specific number of stations required for

assessment will be determined on a site specific basis.

• Since numeric nutrient criteria are intended to protect healthy, well

- balanced natural populations of flora and fauna, the existing nutrient concentrations are deemed
protective if the biology is found to be healthy and protection of downs tream waters is demonstrated pursuant to subparagraph 62

- 302.800(3)(a)3 . The nutrient SSAC will need to address the natural variability in nutrient concentrations and must demonstrate that the designated use s are being protected in the waters covered by t he SSAC and in

downstream waters (this requirement to ensure protection of downstream waters is explicitly described in the rule for Type III SSACs, but it is also required for Type II SSACs for nutrients).

• As part of Type III SSAC development, aquatic lif e use support must be demonstrated. The phytoplankton, periphyton, vascular plant community , and benthic

macroinvertebrates responses are used as primary evidence to demonstrate systems are meeting their designated use (as described above).

• Streams tha t do not exhibit excess algal growth or nuisance aquatic plants and where the average of two temporally independent Stream Condition Index (SCI) results is
greater than 40 are biologically healthy , and the associated nutrient regime is

demonstrated to be p rotective

.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

35 

# I

**MPLEMENTING THE** 

# NNC **R EVISIONS TO**  **THE** 

# I **MPAIRED** 

# W **ATERS** 

# R **ULE** 

# (C **HAPTER** 

# 62

**- 303,**  **F.A.C.)**

The Impaired Waters Rule (IWR , Chapter 62

- 303, F.A.C. ) provides a process to determine if waterbodies (or waterbody segments) should be placed on the Verified List of impaired waterbodies for subsequent

TMDL dev e lopment . The listings are made in accordance with evaluation thresholds

, data sufficiency

and dat a quality requirements in the IWR. The results of the assessment are used to identify waters in each basin for which TMDLs will be developed.

The process for determining impairment in individual waterbodies has been incorporated into the Department’s Wate rshed Management approach. Under this approach, which is based on a 5

- year basin rotation, Florida’s 52 Hydrologic Unit Code ( HUC ) basins (51 HUCs plus the Florida Keys) have been
distributed among 29 basin groups. These basin groups are located within t he Department’s six ( 6 ) statewide districts, with 5 basin groups in each of the Northwest, Central, Southwest, South, and Southeast Districts, and 4 basin groups in the Northeast District. One basin group in each district is assessed each year (except for the Northeast). Table 6 lists the basin groups for each of the Department’s districts that are included in each year of the basin rotation

Implementation of the TMDL Program (monitoring, assessment, identification of impaired waters, development of TMDLs , and implementation) under the rotating Watershed Management approach includes five distinct phases ( Table 7 ). D evelopment of the Planning, Study, and Verified Lists occur in the first two phases of the cycle. As described in greater detail below , there are approximately two years between the initial Phase 1 assessment and the final adoption of the Verified Lists [including the 303(d) list] at the end of Phase 2.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

36 Table 6

. Basin g roups for i mplementing the w atershed m anagement c ycle , by Department d istrict

..

- = No basin assessed **Dept. District**  **Group 1 Basins**  **Group 2 Basins**  **Group 3 Basins**  **Group 4 Basins**  **Group 5 Basins** 

Northwe
st Ochlockonee

– St. Marks Apalachicola

– Chipola Choctawhatch

ee

– St. Andrew Pensacola Perdido

Northea
st Suwannee Lower St. Johns - Nassau

– St. Marys Upper East Coast

Central Ocklawaha Middle St. Johns Upper St. Johns Kissimmee River Indian River Lagoon

Southwe
st Tampa Bay Tampa Bay Tributaries Sarasota Bay

– Peace

– Myakka Withlacoochee Springs Coast

South Everglades West Coast Charlotte Harbor Caloosahatche

e Fisheating Creek Florida Keys

Southea
st Lake Okeechobee St. Lucie

– Loxahatchee Lake Worth Lagoon

– Palm Beach Coast Southeast Coast

– Biscayne Bay Everglades

Table 7

. Phases of the b asin m anagement c ycle

.

**Phase Schedule**  **Activities**

Phase 1:

Preliminary Basin
Evaluation Year 1 • Identify stakeholders/participants
• Obtain data and enter into Florida STORET • Conduct public meeting to introduce cycle

• Primary Products:

– Develop Planning List of potentially impaired waters to identify those waters that need more information to complete a full attainment
decision . (

.

– Develop Strategic Monitoring Plan for information collection to complete a full attainment decision. (A full attainment decision allows the Departme nt to place waters on the verified list if neede d).

Phase 2:

Strategic Monitoring and

Verified List Development Years 2

– 3 • Carry out strategic monitoring to collect additional data identified in Phase 1 • Acquire additional data and enter into Florida STORET • Evaluate new data and incorporate findings into draft version s of Verified List of

Impaired Waters and Delist List • Distribute draft Verified List of Impaired Waters and Delist List for review • Conduct public meetings and solicit comments f rom stakeholders on draft

version of Verified List of Impaired Waters and Delist List

• Primary Products:

– Finalize Verified List of Impaired Waters , Study List, and Delist List for

Secretarial adoption

– Adopt Verified List of Impaired Waters and Delist List by Secretarial Order

– Submit finalized Verified List of Impaired Waters , Study List, and Delist

List to EPA as update to 303(d) list

Phase 3:

TMDL Development Years 2

– 4 • Complete TMDLs for verified impaired waters according to prioritization9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

37 **Phase Schedule**  **Activities**

Phase 4:

Development of
BMAPs Year 4 • Finalize management goals/objectives • Develop draft BMAP, including TMDL allocation • Identify monitoring and management partnerships, needed rule changes and

legislative action, and funding opportunities • Develop Monitoring and Evaluation Plans • Seek funding • Obtain participant commitment to implement plans

Phase 5: Implementation Year 5+ • Implement BMAPs • Carry out rule development/legislative action

In the first phase of the basin cycle, which lasts approximately six months (from July through December)

, the Department evaluates all readily available water quality data for the basin group using the methodology prescribed in the IWR to identify any potentially impaired waters or other waters that

need additional data to determine the restoration actions needed

. For the nutrient assessment, key provisions of the IWR include Sections 62

- 303.350 (Planning List), 62

- 303.390 (Study List), and 62

- 303.450 (Verified List). T he Planning List provisions in the IWR for streams (Rule 62

- 303.351, F.A.C.)

include two referenc es to the numeric nutrient thresholds for streams ( subsection 62

- 302.531(2), F.A.C.). Under subsection 62

- 303.351(1), F.A.C., streams can be placed on the Planning List for nutrient impairment if they do not attain the numeric interpretation of the NNC , w hich requires a combination of
both nutrient and biological data to be fully assess ed . Under subsection 62

- 303.351( 2 ), F.A.C., streams
can also be placed on the Planning List 7 if they exceed the numeric thresholds in subparagraph 62

- 302.531(2)(c)3, F.A.C. , even if there is insufficient biological information to fully assess achievement of

subsection 62

- 302.531(2).

Waters found to be potentially impaired are included on a Planning List for further assessment

, and a Strategic Monitoring Plan (SMP) is prepa red to ensure that the necessary monitoring is conducted during the second phase of the cycle. While the focus of the initial assessment is on the identification of
potentially impaired waters, the assessment is comprehensive, and waters with sufficient i nformation to qualify for the Study List or the Verified List will also be identified. Waters found to be impaired and the
cause is known to be a pollutant are placed in category 3d to indicate tha t no additional data are needed to place the water on the Verified List in Phase 2. Waters that qualify for the Verified List are generally not prioritized for monitoring because sufficient data have already been collected; however, there may be cases where the Department may conduct additional monitoring (for e xample, to confirm the causative pollutant or to confirm suspect data). Regardless of whether additional data are collected, the waters will not be adopted on the Verified List until the end of Phase II of the cycle.

The SMP will also address sampling o f waters that were placed on the Study List during the previous
Watershed Management cycle. It should be noted that s ome of the waters on the Planning List will also qualify for the Study List during Phase 1

. T he se waters will not be placed on the official Study List submitted to EPA for 303(d) list approval until the conclusion of Phase II and only in those circumstances

7 These waters would also be eligible for the “Study List” if sufficient biological data are not collected during the Strategic Monitoring phase.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

38 where the needed data or information is n ot collected during the strategic monitoring phase (due to

dr o ught, for example)

.

The second phase of the Watershed Management cycle includes two distinct activities: completion of

the SMP and re

- assessment of the basin’s waterbodies using the new data. The strategic monitoring phase, which lasts a full calendar year, is focused on those waters that were placed on the Planning List during the first phase of the basin rotation or the Study List during the previous cycle , with the goal of ensuring that sufficient data and/or ancillary information are available to determine (i.e., to “verify” )

— using the methodology described in the IWR

— whether a waterbody segment is impaired and if the impairment is caused by a pollutant.

A fter the monitoring is completed, all of the waterbodies in the basin are re

- assessed, taking into

account the new data collected by the Department and any other new information from other data
providers . This re

- assessment process typically lasts another full calendar year, with draft assessments

conducted in the spring and presented to the public in June, revised assessm ents conducted in the summer and presented to the public in the fall, and final lists adopted by the Secretary at the end of the

year.

Waters are re

- assessed for nutrient impairment pursuant to Rule 62

- 303.450, F.A.C. There has been some confusion expre ssed about the meaning of the text in Rule 62

- 303.450(3), F.A.C., which states that waters shall be placed on the Verified List “upon confirming the imbalance in flora or fauna based on the last 7.5 years of data

. ” The only confirmation required is that t he nutrient criteria have been exceeded within the last 7.5 years, and no additional biological information is required for waters listed on the Planning List under the referenced rule provisions. However, Rule 62

- 303.450(3), F.A.C., does not

reference th e Planning List rule provision that lists streams on the Planning List based on exceedances of the nutrient stream thresholds without sufficient biological information (Rule 62

- 303.35 1 (2), F.A.C.).

These waters will be targeted during the SMP so that they can be fully assessed against the numeric interpretation of the NNC for streams.

W aterbody segments identified and verified as impaired are placed on the state’s Verified List of
impaired waters

, and those waterbody segments determined to be no longer impaired or in need of a TMDL are placed on the Delist List. After the additional year of data collection, s urface waters or

segments that do not attain surface water quality standards, but the cause of nonattainment is still

unknown

, or waters where there is still insufficient information to fully assess the water quality standard are placed on the Study List so that additional monitoring can be conducted to identify the cause of
impairment or fully impl ement the water quality standard

.

For waterbodies on the Planning List due to adverse trends in a nutrient or nutrient response variable, the Department will conduct additional trend analysis during Phase 2 to determine the appropriate listing category f or the waterbody. Because it is well known that nutrient loads in natural watersheds may fluctuate according to climatologic, hydrologic, and/or seasonal patterns, it is important to control
for these confounding factors when performing the trend analyse s. The Department is confident that any increasing trends in anthropogenic nutrient loading will be observed using valid statistical9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

39 approaches ( e.g ., regression and subsequent residuals analyses), because removal of confounding influences improves the ability to detect an anthropogenic signal. One of t he following actions can

occur related to trend assessments at the end of the Phase 2 analysis:

1. If the Department determine s there is not a statistically significant increasing trend in TN, TP, or a nutrient response variable after controlling f o r confounding variables, then the waterbody will

be removed from the P lanning L ist for nutrients

.

2. If the Department determine s there is a statistically significant increasing trend in TN, TP, or a

nutrient response variable after controlling for confounding variables and the waterbody is
expected to become impaired within 6

- 10 years , then it will be placed on the S tudy L ist

, pursuant to paragraph 62

- 303.390(2)(a)

, F.A.C.

The waterbody will be removed from the S tudy L ist when a site specific interpretation (a SSAC in this case) of the NNC is established . If a site

- specific interpretation of the narrative has already
been established, then the waterbody will be re

- evaluated to ensure the attainment and maintenance of water quality standards in downstream waterbodies.

3. If there is a significant adverse trend in a nutrient response variable and the waterbody is expected to become impaired within 5 years, then the waterbody will be place d on the Verified
List for nutrient impairment, pursuant to subsection 62

- 303.450(4), F.A.C.

Both t he Verified List and D elist Lists are adopted by Secretarial Order in accordance with the Florida Watershed Restoration Act ( FWRA ) . Once adopted, the Verified, Delist and Study list s are submitted to the EPA for approval as an update to the state’s Section 303(d) list of impair ed waters.

As demonstrated through this process, a waterbody may be placed directly on the Verified List if sufficient data are available even if it was not previously identified as potentially impaired in Phase 1 of the Watershed Management cycle. Furthermore, there is no requirement that waters be plac ed on either the Planning List or Study List before they can be placed on the Verified List.

If a waterbody is placed on the Study List, it is the Department ’s goal to complete the needed monitoring/analysis during either the same or the next Watershed M anagement cycle. Because waters on the Study List will be included on the State’s 303(d) list, there will be significant pressure by both the environmental and regulated communities to complete the needed studies in a timely manner. If
resources allow, t he Department will include a second strategic monitoring phase in the Watershed Management cycle (likely concurrent with Phase 3, TMDL Development). However, the Department may need to wait until the Strategic Monitoring phase of the next watershed cycle. As a result, the studies should be completed and the waterbody moved to the Verified or Delist List (as appropriate) within six years of placement on the Study List.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

40 

## Assessment of Estuaries

As noted previously, the Department has adopted estuary

- specifi c numeric interpretations of the NNC in paragraph 62

- 302.530(47)(b), F.A.C., for estuaries along the Southwest Coast (roughly from Tampa Bay to Miami and the Florida Keys) . With the exception of the criteria developed for Tampa Bay, which are expressed as delivery ratios (addressed in next section), assessment of the estuary

- specific numeric
interpretations is straightforward because the listing thresholds for both the Planning and Verified Lists are directly based on exceedances of the adopted numeric int erpretations of the NNC [ see Subsections

62

- 303.353(1), and 62

- 303.450(3), F.A.C. ] For this assessment, the only added review elements under the IWR include the time frame (10 years for Planning List and 7 years for the Verified List) and an

evaluation of whether the data were collected under extreme climatic conditions (the Department will not list waters as impaired based solely on extreme climatic conditions or changes in the monitoring network).

For estuarine systems without adopted estuary

- specific nu meric interpretations of the NNC , the Department will continue to assess the NNC pursuant to Subsection 62

- 303.353(3), F.A.C. (Planning List)

and Subsection 62

- 303.450(2), F.A.C. (Verified List), and assess the 11 ug/l chlorophyll a impairment

threshold fo r estuaries pursuant to Subsection 62

- 303.353(2) (Planning List) and Subsection 62

- 303.450(1), F.A.C. (Verified List).

It should be noted that subsection 62

- 303.450(1), F.A.C., incorrectly references subsection 62

- 303.353 (1) , when it should have referenced subsection 62

- 303.353 (2)

. The Department intended to

reference subsection 62

- 303.353(2), which assesses estuaries against the long

- standing 11 ug/L nutrient
impairment threshold for estuaries. In contrast, subsection 62

- 303.353(1) is part of the nutrien t assessment that places waters on the planning list if they exceed the numeric interpretations of the NNC

established in subsection 62

- 302.531(2), which for estuaries would include nutrient TMDLs and the
newly adopted estuary

- specific numeric interpretati ons in Rule 62

- 302.532, F.A.C. These estuary

specific numeric interpretations, which establish independently applicable TN, TP, and chlorophyll a criteria for estuaries from Tampa Bay to Miami and the Florida Keys, are assessed under Subsection 62

- 303.450 (3). In fact, subsection 62

- 303.450(3) also references subsection 62

- 302.353(1), and this redundant rule citation further supports the fact that we inadvertently referenced the wrong rule in 62

- 303.450(1).

The Department plan s to correct the rule referen ce as part of the ongoing Triennial Review of Florida’s
Water Quality Standards, which is currently scheduled for ERC adoption in December. We also plan to clarify that the 11 ug/L chlorophyll nutrient impairment threshold will not be assessed in estuarie s with

estuary

- specific chlorophyll a criteria. This is consistent with the hierarchy in Rule 62

- 302.531, (2),

F.A.C., which establishes site specific numeric interpretations of the NNC as the primary interpretation

of the NNC

.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

41 

## Assessment of Waterbod ies with Interpretations of the N NC Expressed as Loads or Delivery Ratios

For waters with nutrient TMDLs expressed as a load, attainment of the allowable loads will be evaluated as part of the BMAP reporting process, and nonattainment will be assumed until information is provided to prove attainment (a combination of model estimated loads of nonpoint sources and measured loads from point sources). Waters should only be deemed to be in attainment if they meet the loads (or concentrations) and targets ( e.g., chlorophyll) and a demonstration is made that nutrients are no longer causing biological imbalances. If the waterbody attains the allowable loading but there is site

- specific information indicating an imbalance in flora or fauna, the TMDL would be revisi ted and revised as

needed.

For the Tampa Bay estuarine system where nutrient standards are expressed as a delivery ratio, the Tampa Bay Estuary Program has agreed, pursuant to their binding Reasonable Assurance agreement, to provide the hydrologic and load ing information (for both point and nonpoint sources) needed to

calculate and assess annual delivery ratios on at least a five year frequency, which is consistent with
DEPs watershed assessment cycle. However, TBEP has agreed to evaluate chlorophyll a tar gets on an annual basis, and will provide the Department with the needed information more frequently if chlorophyll a targets are exceeded for two consecutive years.



### I MPAIRED 

### W ATERS 

### R ULE 

### A SSESSMENT 

### S UMMARY

• The IWR was revised to be consistent with the re visions to Chapter 62

- 302, F.A.C., including provisions to implement the NNC for lakes, springs , and streams

.

• Streams that exceed reference

- based nutrient thresholds will be placed on the Study List unless there are bioassessment data (flora and fauna) i ndicating the stream is healthy. Streams that exceed reference

- based nutrient thresholds and have information that indicate imbalances of flora are placed directly on the Verified List. Waters on the Study

List will receive a site

- specific physical, chem ical, and biological investigation to determine if aquatic life use support goals are attained (if there were no bioassessment data available), and if aquatic life use support is not attained, to determine the causative pollutant(s). This process constitu tes a “stressor identification” study. If the stream is determined to be impaired due to nutrients (at least in part), the water will be listed on the Verified List for TMDL development, which will determine the reductions
needed. This approach places wa ters on the Study List if there is a nonattainment condition based on the current numeric interpretation of the narrative criteri on outlined above, and places waters on the IWR Verified List for nutrients if they need a reduction in a nutrient loading to a ttain the NNC or otherwise restore the waterbody’s designated

use.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

42 

# S **URFACE** 

# W **ATER** 

# D **ISCHARGE** 

# W **ASTEWATER** 

# P **ERMITS**

This chapter describes how the site

- specific interpretations of the NNC in Rules 62

- 302.531 and 62

- 302.532, F.A.C., are implemented in surface w ater discharge wastewater permits (see Figure 7 )

, including:

• T he permit application process;

• The expectations for providing reasonable assurance and for calculating Water Quality Based Effluent Limitations for nutrients; and

• How permits will be reviewed with respect to meeting numeric nutrient standards both

in near

- field receiving waterbodies as well as downstream waterbodies.

Figure 7

. Flow chart illustrating the process by which NNC will be implemented in surface water
discharge wastewater permits.

Although it is ultimately the Department’s responsibility to assure that adequate documentation is in the administrative record for permi tting decisions, Florida’s permitting process puts the burden on the applicant to provide all of the necessary documentation for permit issuance. Rule 62

- 620.320, F.A.C., (Standards for Issuing or Denying Permits) requires that:

“ (1) A permit shall be is sued only if the applicant affirmatively provides the Department with reasonable assurance, based on a preliminary design report, plans, test results, installation of pollution control equipment, or other information, that the construction, modification, o r operation of the wastewater facility or activity will not discharge or cause pollution in contravention of chapter 403, F.S., and applicable Department rules.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

43 (2) If, after review of the application and any pertinent information, the Department determin es that the applicant has not provided reasonable assurance that the construction, modification, or operation of the wastewater facility or activity will be in accordance with applicable statutes or rules, including rules of approved local programs under 4 03.182, F.S., the Department shall deny the permit, shall notify the applicant, and specify the reasons for the denial. ”

The se information requirements are spelled out in the Department’s “Guide to Permitting Wastewater Facilities or Activities Under Chapter 62

- 620, F.A.C.” The guide reiterates the rule requirement that the applicant has the burden to submit documentation with the application providing reasonable assurances

that the criteria in rule 62

- 302, F.A.C. and other applicable department rules shall be met.

The WQBEL process, pursuant to Chapter 62

- 650, F.A.C., is the mechanism for determining the levels of nutrients in a point source discharge (i.e., effluent nutrient l imits) that attain the NNC in paragraph 62

- 302.530(47)(b), F.A.C. Derivation of a level II nutrient WQBEL is a site

- specific, hierarchy 1 interpretation

of the NNC and the WQBEL derivation is based on the worst

- case scenario (permitted flows) and the

asso ciated nutrient loads from a discharge. If downstream waters are anticipated to be potentially

affected by the discharge of nutrients from an upstream facility, th e potential impact must be assessed

, regardless of distance (see section on “ NNC and Protect ion of Downstream Waters ”)

.

Revisions to a WQBEL for existing discharges are implemented through the permit renewal process and
compliance schedules may be used to give permittees time to come into compliance with any new requirements pursuant to the pro visions of subsection 403.088(2)(e) and (f), F.S., and subsections 62

- 620.610(12) and 62

- 620.620(6), F.A.C. New or expanded discharges are subject to the antidegradation review, and if the discharge contains nutrients, it will need to have a WQBEL establi shed and provide

reasonable assurance at the time the permit is issued that the WQBEL will be met. Existing WQBELs are reviewed at the time of permit renewal (every five years), and if the factors associated with the
derivation of the WQBEL have not subst antively changed during the five year period, the WQBEL can be considered valid for another five year period.



### WQBEL P ROCEDURES FOR 

### E ACH 

### T IER OF THE 

### H IERARCHY

1. In accordance with paragraph 62

- 302.531(2)(a), F.A.C., where a site specific numeric interpreta tion of paragraph 62

- 302.530(47)(b), F.A.C., has been established by the Department, that interpretation is the applicable interpretation. Such interpretations include Total Maximum Daily Loads (TMDLs), site specific alternative criteria (SSAC) for nutrie nts, Reasonable Assurance (RA) demonstrations, or

other site

- specific interpretations that are formally established by rule or final order of the Department. The applicable interpretations, if available, include both nutrient [e.g. total nitrogen (TN) or total phosphorus (TP)] and response variables (e.g. chlorophyll a ). Where multiple interpretations have been made for a waterbody, the most recent is the applicable interpretation. If only one nutrient (e.g., TP) has a numeric interpretation established in accordance with paragraph

62

- 302.531(2)(a), F.A.C., the numeric interpretation of the narrative nutrient criteria for the other nutrient (e.g., TN) follows the hierarchy described in paragraph 62

- 302.531(2), F.A.C. The
Department will maintain a listin g of the site

- interpretations established to date available on the
Department website.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

44 Site

- specific interpretations are used to establish WQBELs as follows:

• TMDLs

– Where a TMDL 8 is the applicable interpretation, a WQBEL is derived in accordance with the Wasteload Allocation provided in the TMDL. In accordance with

subsection 62

- 302.531(8), F.A.C., if the Wasteload Allocation is expressed as a load, the
WQBEL can be expressed as a load 9 (i.e. there is no requirement to “translate” the load to a concentration for the WQBEL).

• SSAC

– Where a SSAC is the applicable interpretation, a WQBEL is derived to ensure that the discharge does not cause or contribute to an exceedance of the SSAC within the spatial area to which the SSAC is applicable (e.g. if a SSAC for a stream segment has been established as an annual geometric mean of 40 μ g/L total phosphorus, the WQBEL
is calculated to ensure that the discharge does not cause or contribute to the stream segment exceeding an annual geometric mean of 40 μ g/L), in all years. If the
waterbody currently achieves the SSAC value, the Level I WQBEL process can be used to establish effluent limits consistent with permitted nutrient levels, but only if the permit applicant is not expanding its discharge above currently permitted levels and will not increase its nutrient concentrations over the permit cycle. However, if the waterbody does not achieve the SSAC or if the permit is for a new or expanded d ischarge, the Level
II WQBEL process is more appropriate.

• Reasonable Assurance (RA) Demonstration

– Where the Department has approved an RA demonstration pursuant to the subsection 62

- 303.100(5), F.A.C., related to nutrient
impairment, the nutrient

- related target in the RA demonstration can serve as the applicable numeric interpretation of the narrative nutrient standard. The WQBEL would then be calculated to ensure attainment of that numeric interpretation in the same
manner as the TMDL or SSAC procedures , depending on how the RA demonstration was crafted. For example, if the RA demonstration included an allocation to a permitted facility, that allocation can be treated as the Wasteload Allocation similar to those

contained in a TMDL.

For the examples abo ve that include a Wasteload Allocation, the WQBEL is established using the Level I process at Rule 62

- 650.400, F.A.C., to implement the site

- specific interpretation of the narrative. If the Department determined that a facility will not cause or contribut e to nutrient impairment and did not establish a Wasteload Allocation for the facility, permit limits are not required, pursuant to the TMDL; however, such a facility would not be allowed to increase its nutrient loading and permit limits may be needed if increased discharge is being sought. Where a
TMDL, SSAC or R A Demonstration does not exist, a WQBEL is recognized as the applicable interpretation of the narrative nutrient criteria if:

8 TMDL means a TMDL adopted under Chapter 62

- 304, F.A.C., that interprets the narrative water quality criterion for nutrients in paragraph 62

- 302.530(47)(b), F.A.C., for one or more nutrients or nutrient response variables.

9 Note

– permit load (mass) limi ts are generally expressed as a rolling annual load.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

45 a) T he documentation for the WQBEL includes a site specific numeric int erpretation of the

narrative criterion at paragraph 62

- 302.530(47)(b), F.A.C.

, for the waterbody ; b) The WQBEL is established pursuant to the Level II Process contained at Rule 62

- 650.500,

F.A.C. ; and c) T he public notice for the WQBEL specifically state s that the Level II WQBEL includes a site specific interpretation of the narrative for the receiving waterbody.

Where a Level II WQBEL has previously been established for discharge of nutrients to a waterbody
and a TMDL, SSAC, or RA does not exist for the wate rbody, the existing WQBEL remains in effect until revised by a Final Order that establishes a site specific interpretation of the narrative.
Revisions to the WQBEL to reflect the site

- specific interpretation will generally be implemented
through the permi t renewal process, and compliance schedules may be used to give permittees time to come into compliance. In certain cases permits may need to be re

- opened prior to permit
renewal to include revised WQBELs based on priority of restoration needs, time remai ning before
permit renewal, and workload considerations.

2. If there is no site

- specific interpretation in effect as described in the preceding paragraph that is applicable to the receiving waters, but there is an established, quantifiable stressor respon se relationship between one or more nutrients and nutrient response variables for those waters, then the values set forth in paragraph 62

- 302.531(2)(b), F.A.C., are the applicable numeric interpretation of paragraph 62

- 302.530(47)(b), F.A.C. Such an inter pretation has only been made at this time for
lakes and spring vents. There are currently no discharges directly to spring vents and it is unlikely that such discharges will be proposed in the future. Effluent limits for discharges to ground waters

in th e springshed are developed through the standard process for groundwater discharges (see separate document on discharges to groundwater) or through the TMDL /Basin Management Action

Plan process for that spring where sufficient information exists

.

For lakes, the WQBEL may be derived to ensure that the discharge does not cause or contribute to

exceedances of the numeric interpretation for the waterbody segment , which is expressed as a lake average. As stated previously, Florida’s wastewater permitting p rocess puts the burden on the applicant to provide all of the necessary documentation for permit issuance , including demonstrating that their discharge will not cause violations of the water quality standards
applicable to the lake. Depending on the circum stances of the lake, either a Level I or Level II WQBEL is established that implements this numeric interpretation of the narrative criteria. This is
accomplished as follows:

• If the discharge can meet the applicable numeric interpretation, a Level I WQB EL is calculated to ensure the discharge does not exceed the Total Nitrogen and Total Phosphorus values contained in sub

- subparagraph 62

- 302.531(2)(b)1.a., F.A.C.; or

• For existing discharges, a Level I WQBEL can be established at permitted nutrient loa ds if the receiving lake attains the numeric interpretation of the narrative expressed at sub

subparagraph 62

- 302.531(2)(b)1.a., F.A.C.; or9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

46 • For new or expanded discharges to a lake that attains the applicable criteria, a Level II
WQBEL must be establish ed that ensures the lake will continue to attain the numeric interpretation of the narrative; or

• If the lake does not attain the baseline TN or TP values in sub

- subparagraph 62

- 302.531(2)(b)1.a., F.A.C., but attains the applicable chlorophyll a value in s ub

subparagraph 62

- 302.531(2)(b)1.a., F.A.C., a Level II WQBEL must ensure attainment of
the applicable chlorophyll a value in all years. The Level II WQBEL must also ensure that ambient lake nutrient conditions do not exceed the upper end of the range To tal Nitrogen and Total Phosphorus limits in sub

- subparagraph 62

- 302.531(2)(b)1.b., F.A.C.

In any case, a new or expanded discharge would need to conduct water quality modeling during critical conditions to provide the reasonable assurance that the discha rge will not cause a violation of lake water quality standards during critical conditions. Note that the WQBEL is subject to change upon permit renewal if a site specific interpretation is established pursuant to par agraph 62

- 302.531(2)(a), F.A.C.

3. Fo r streams in which an applicable interpretation (i.e., TMDL, SSAC, RA) has not been made as described in paragraph 1, the provisions set forth in paragraph 62

- 302.531(2)(c), F.A.C., are the applicable numeric interpretation of paragraph 62

- 302.530(47)(b)

, F.A.C. A continuous discharge facility that has effluent nutrient concentrations greater than the applicable numeric nutrient
thresholds adopted at Subparagraph 62

- 302.531(2)(c)2, F.A.C.

, will require that effluent limits be
established as necessary to m eet the nutrient standards in Chapter 62

- 302, F.A.C. In that case, a WQBEL that implements the numeric interpretation of the narrative criteria is derived as follows:

• If the stream receiving an existing discharge has evidence of balance d flora based on

av ailable information on chlorophyll a levels, algal mats or blooms, nuisance
macrophyte growth, and changes in algal species composition and either is achieving the reference thresholds at subparagraph 62

- 302.531(2)(c)2., F.A.C., or the re is evidence of bal anced fauna based on available Stream Condition Index (SCI) scores 10 , the waterbody will be deemed to have attained the standard at paragraph 62

- 302.531(2)(c), F.A.C.

, and the narrative criterion of paragraph 62

- 302.530(47)(b), F.A.C.
In that case, the Lev el I WQBEL process is used to establish effluent limits consistent with permitted nutrient loads if the permit applicant is not expanding its discharge above currently permitted levels and will not increase their nutrient concentrations over the permit cyc le . However, if a facility is discharging significantly below its permitted capacity, the Department will review the WQBEL that was the basis for the current permit limits to ensure that it is still a valid interpretation of the NNC . T he Level II WQBEL process is available for new discharges or facility expansions that result in

10 See Section 2.7 of the SCI Primer for details on the floral assessment.9

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

47 increased nutrient loads 11 . A WQBEL for a new or expanded nutrient discharge must ensure that a healthy, well balanced floral community will be attained at the proposed discharge, and that either the nutrient thresholds will be achieved in the receiving stream (averaged over appropriate stream segments with homogeneous water quality) or that the waterbody has healthy fauna (SCI). If SCI measurements indicate tha t the waterbody is not biologically healthy AND a stressor identification study indicate s that
nutrients are the cause, the WQBEL that prevents nutrients from impacting stream fauna would need to be calculated

. If insufficient biological data are available 12 to determine if the stream is healthy, pursuant to
paragraph 62

- 302.531(2)(c), F.A.C., the applicant may collect additional biological data to provide reasonable assurances. If the additional biological data indicate that the stream is not healthy,

the following scenario will apply.

• If the stream receiving an existing discharge has evidence of imbalance in flora based on available information on chlorophyll a levels, algal mats or blooms, nuisance
macrophyte growth , then the waterbody is not achieving th e narrative criterion of paragraph 62

- 302.530(47)(b), F.A.C ., regardless of whether the reference thresholds at
paragraph 62

- 302.531(2)(c), F.A.C. or the SCI thresholds are met. If the flora are
determined to be healthy, but n either the reference threshol ds at subparagraph 62

- 302.531(2)(c)2., F.A.C., nor the SCI thresholds are met, then the waterbody is also not achieving the narrative criterion of paragraph 62

- 302.530(47)(b), F.A.C

. In that case, the discharge to that waterbody is not allowed unless a le vel II WQBEL is developed or other administrative process is implemented that ensures the discharge does not cause or contribute to nonattainment of subparagraph 62

- 302.531(2)(c)2., F.A.C. or the narrative criterion of paragraph 62

- 302.530(47)(b), F.A.C. In the circumstance where flora are balanced, but the SCI fails, a stressor identification study would likely be needed as part of the Level II WQBEL evaluation. Stressor identification studies evaluate and identify causes of biological impairment, includ ing both pollutant and hydrologic/habitat related stressors.

Where a stream is verified as impaired for nutrients pursuant to the impaired waters rule, a site

specific interpretation of the narrative nutrient standard will be developed as part of the TMDL process, which will include Wasteload Allocations for discharges to the stream. The subsequent WQBEL would be consistent with the Wasteload Allocation. As noted previously, the WQBEL is subject to change upon permit renewal if a site specific interpreta tion is established pursuant to

par agraph 62

- 302.531(2)(a), F.A.C.

11 Since paragraph 62

- 302.532(7)(d), F.A.C., specifies that the spatial application of the numeric interpretation shall
be determi ned by relative stream homogeneity and shall be applied to waterbody segments or aggregations of segments as determined by the site

- specific considerations, mixing zones are not applicable.

12 Biological data are available to the applicant through the Depar tment’s website at http://ca.dep.state.fl.us/mapdirect/?focus=waterdatacentral9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

48 WQBELs established by all of the above methods must prevent discharges from causing or contributing

to a violation of the NNC in paragraph 62

- 302.530(47)(b), F.A.C. Also, in accordance w ith Subsection 62

- 302.531(4), F.A.C., WQBEL s cannot allow the loading of nutrients from a waterbody to cause or contribute to an exceedance of water quality standards in a downstream waterbody. The reasonable

assurance demonstration that the construction, modification, or operation of the wastewater facility or activity will meet this requirement may include information that: a) water quality standards of

downstream waters are being attained with the existing discharge, b) the existing or future discharge
does or will not affect downstream waters, or c) the discharge is in co mpliance with downstream

TMDLs.

Finally, a permittee has the option of pursuing relief from any of the above si te

- specific interpretations
through the establishment of Site Specific Alternative Criteria under Rule 62

- 302.800, F.A.C., a variance under the provisions of 403.201, F.S., or a designated use modification under Rule 62

- 302.400, F.A.C.9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

4 9 

## Appendix A. Minim ally Disturbed and Healthy Streams

**Table A**

**- 1. List of healthy streams (passing SCI) used to inform RPS**  **expectations.**

STORET ID Station Description RPS Average

Percent 4 to 6

Scores Mean SCI

2007

Score SCI

2007

(n)

3497 Fisheating Creek @ Cr 27 0.0% 54 1

3509 ANCLOTE RIVER MOUTH AT S.R. 54 0.0% 47 1

3513 Withlacoochee River @ Stokes Ferry 40.4% 43 3

3531 S321 Econfina Creek 0.0% 73 1

3535 SUW010 Suwannee River 83.8% 61 1

3536 S418 Alaqua Creek 4.0% 90 1

3542 S250 Perdido River 9.1% 57 1

3545 S360 Blackwater River @ Hwy 4 4.0% 58 2

3546 S365 Yellow River @ Hwy 2 0.0% 79 1

3549 S377 Escambia River @ HWY 4 Bridge 0.0% 51 1

3554 FLO 57 162 0 Alafia River 28.8% 70 2

3555 Little Manatee River at HWY 301 2.5% 63 2

3569 Little Econlockhatchee River 5.1% 46 1

14264 SJB

- LR

- 1006 BLACK CREEK 2.0% 73 1

21179 Spruce Creek 0.0% 45 1

21200 Rice Creek at SR100 4.0% 69 1

21201 Moultrie Creek 11.1% 63 1

21202 Orange Creek 1.0% 73 2

21460 Wrights Creek at CR 177A 4.0% 76 1

21461 BIG COLDWATER CR @ CR 191 1.0% 76 1

36366 Z2

- LR

- 3010 Suwannee River 0.0% 57 1

36631 Z3

- SS

- 3009 unnamed small stream 1.0% 83 1

36634 Z3

- SS

- 3014 Trout River 2.0% 57 2

36636 Z3

- SS

- 3038 Two mile Creek 1.0% 43 2

36639 Z2

- SS

- 3003 Roaring Creek 0.0% 46 1

36641 Z2

- SS

- 3016 unnamed small stream 31.8% 73 2

36642 Z2

- SS

- 3030 unnamed small stream 0.0% 51 2

36646 Z2

- SS

- 3068 unnamed small stream 1.0% 79 2

36648 Z2

- SS

- 3075 unnamed small stream 0.0% 66 2

36998 Z4

- LR

- 3004 Alafia River 21.7% 41 2

37003 Z4

- LR

- 3022 Peace River 7.1% 48 2

37006 Z4

- LR

- 3032 Anclote River 27.3% 43 2

37108 Z5

- LR

- 3012 Lake Marion Creek 0.0% 45 1

37111 Z5

- LR

- 3016 Boggy Creek 38.4% 47 29

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

50 STORET ID Station Description RPS Average

Percent 4 to 6

Scores Mean SCI

2007

Score SCI

2007

(n)

37506 Z1

- LR

- 3008 Big Water Coldwater 0.0% 82 2

37508 Z1

- LR

- 3011 Holmes Creek 7.6% 64 2

37539 Z1

- SS

- 3006 Alaqua Creek 0.5% 90 2

37540 Z1

- SS

- 3007 Williams Creek 0.0% 67 2

37542 Z1

- SS

- 3010 unnamed stream 2.5% 62 2

37543 Z1

- SS

- 3012 unnamed stream 0.0% 60 2

37544 Z1

- SS

- 3013 unnamed stream 0.0% 72 2

37545 Z1

- SS

- 3022 titi creek 1.5% 76 2

37546 Z1

- SS

- 3025 Alaqua Creek 1.0% 79 2

37547 Z1

- SS

- 3026 Horsehead Creek 0.0% 46 1

37548 Z1

- SS

- 3027 unnamed stream 4.0% 59 2

38195 Z3

- SS

- 3049 South prong St. Mary's River 6.1% 93 1

38441 Z2

- LR

- 4004 Withlacoochee River 0.0% 52 2

38442 Z2

- LR

- 4005 Suwannee River 0.0% 50 2

38444 Z2

- LR

- 4008 Aucilla River 0.0% 49 2

38445 Z2

- LR

- 4009 Suwannee River 0.0% 41 2

38448 Z2

- LR

- 4012 Aucilla River 11.1% 55 2

38450 Z4

- LR

- 4002 Peace River 0.0% 52 2

38451 Z4

- LR

- 4003 Braden River 8.1% 51 2

38453 Z4

- LR

- 4005 Pithlachascottee River 0.0% 74 2

38454 Z4

- LR

- 4006 Horse Creek 16.2% 58 2

38455 Z4

- LR

- 4009 Withlacoochee River 24.2% 42 1

38458 Z4

- LR

- 4012 N. Prong Alafia River 1.0% 62 2

38479 Z1

- LR

- 4001 Ochlockonee River 0.5% 45 2

38480 Z1

- LR

- 4002 Chipola River 0.0% 59 2

38481 Z1

- LR

- 4003 Choctawhatchee River 4.0% 66 2

38482 Z1

- LR

- 4004 East Fork Creek 20.2% 64 2

38484 Z1

- LR

- 4006 Ochlockonee River 0.0% 58 2

38485 Z1

- LR

- 4007 Chipola River 16.2% 58 2

38486 Z1

- LR

- 4008 Yellow River 1.0% 66 2

38488 Z1

- LR

- 4011 Yellow River 0.0% 67 2

38502 Z5

- LR

- 4004 Boggy Creek 0.0% 57 1

38504 Z5

- LR

- 4009 Fisheating Creek 35.4% 60 1

38520 Z3

- SS

- 4008 Gee Creek 0.5% 48 2

38521 Z3

- SS

- 4010 Simms Creek 0.0% 90 1

38525 Z3

- SS

- 4023 Two Mile Creek 0.5% 47 2

38529 Z3

- SS

- 4051 unnamed stream 2.0% 77 19

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

51 STORET ID Station Description RPS Average

Percent 4 to 6

Scores Mean SCI

2007

Score SCI

2007

(n)

38559 Z1

- SS

- 4003 unknown stream 4.5% 60 2

38560 Z1

- SS

- 4006 unknown stream 0.0% 68 2

38561 Z1

- SS

- 4009 unknown stream 0.0% 77 2

38562 Z1

- SS

- 4013 unknown stream 0.0% 93 2

38563 Z1

- SS

- 4015 unknown stream 0.0% 47 1

38564 Z1

- SS

- 4017 unknown stream 5.1% 62 2

38565 Z1

- SS

- 4018 unknown stream 0.0% 81 2

38566 Z1

- SS

- 4022 unknown stream 0.0% 68 2

38568 Z1

- SS

- 4027 unknown stream 0.0% 70 2

38570 Z5

- SS

- 4008 Telegraph Creek 0.0% 54 1

38571 Z5

- SS

- 4022 unnamed small stream 0.0% 58 1

38572 Z5

- SS

- 4034 Gore Branch 7.1% 44 1

38573 Z5

- SS

- 4041 Arbuckle Creek 0.0% 45 1

38574 Z5

- SS

- 4056 Bedman Creek 0.0% 51 1

38580 Z6

- SS

- 4010 Mosquito Creek 2.0% 57 1

38603 Z2

- SS

- 4029 Water Oak Creek 0.0% 64 1

38605 Z2

- SS

- 4033 unnamed Stream 0.0% 67 1

38607 Z2

- SS

- 4040 Mitchell Creek 0.0% 62 1

38609 Z4

- SS

- 4002 Oak Creek 33.3% 52 1

38610 Z4

- SS

- 4004 Gator Creek 0.0% 52 2

38612 Z4

- SS

- 4020 Blackwater Creek 14.1% 64 1

38614 Z4

- SS

- 4024 unnamed stream 33.3% 59 1

19010006 ST MARYS RIVER AT SR #2 0.0% 103 1

19010041 St Mary's River at CR 125 0.0% 78 1

19010076 Calkins Creek at Turner Cemetary Road 0.0% 76 2

19020052 Alligator Ck east of US301 & SR115 0.0% 63 1

20010204 Lt Wekiva R, 100 yd dwnstr of Altamonte Spgs STP 38.9% 53 2

20010333 Robert's brnch @ curryville rd 20.7% 65 2

20010431 WEKIVA R. UPSTRM OF ROCK SPRINGS 65.7% 56 2

20010438 WEKIVA R UPSTR OF BLACKWATER CR 49.5% 82 1

20020317 SILVER RUN AT CONFLUENCE WITH BOAT

RAMP CANAL 33.3% 57 1

20030388 PETERS CREEK #2 CULVERT SR 315 0.0% 86 1

20030481 South Fork Black Creek @ SR 21 0.0% 83 1

20030920 Mormon Branch upstream of SR 19 in
Ocala NF 25.3% 69 3

21010008 ALAPAHA RIVER 1 SR 150 HAMILTON 9.1% 59 19

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

52 STORET ID Station Description RPS Average

Percent 4 to 6

Scores Mean SCI

2007

Score SCI

2007

(n)

21010018 Falling Creek @ CR 131, above falls

Suwannee R. 0.0% 54 2

21010033 Little Creek @ US 441 0.0% 89 1

21010040 Suwannee River above White Springs

WWTP 3.0% 69 1

21010054 PCS Phosphate FYI5, test site 1 0.0% 52 1

21020001 SUWANNEE R U/S FR CONFL SWIFT CR 0.5% 58 2

21020062 SUWANNEE R ~ 150M D/S SWIFT CREEK 0.0% 52 2

21020098 Bethel Creek S Frk at SR 53 0.0% 76 1

21020124 LITTLE CR. ~ 300 M UPSTREAM

SUWANNEE R 0.0% 73 2

21030011 SANTA FE R #6 AT SR 47 90.9% 49 1

21030049 NEW RIVER AT SR 18 0.0% 76 1

22020093 Quincy Creek above SR267 bridge 0.0% 57 1

22040004 AUCILLA R AT US 90 0.0% 61 1

22040009 WASCISSA R #1 AT BIG BLUE SPRING 65.7% 40 1

22040041 Wacissa River Bio Site 2 4.0% 65 1

22050083 Steinhatchee @ Canal Road 34.3% 52 2

23010444 WITHLACOOCHEE R@CANOE LAUNCH IN

LACOOCHEE PARK 29.3% 52 1

23010464 Withlacoochee R @ county park off Auton Rd (TP3) 5.6% 43 2

23020001 Waccasassa R at US 19 20.2% 66 2

23020020 Waccasassa River @ WMA 0.0% 80 2

23020021 Waccasassa River @ OB Road #3 0.0% 82 2

24010002 Manatee R 20 m below SR64 bridge (TP1) 41.4% 64 1

24010063 Gamble Crk, East on Golf Course Rd. 2.0% 43 2

24020080 Alafia Rv

- TP 80 8.6% 55 2

24020361 Alafia River S Prong @ Bethlehem Road 0.0% 67 1

24030044 Hillsborough R in Hills River State Park (TP5) 3.5% 66 2

24030081 Itchepackasassa Ck @ CR 582 0.0% 58 2

24040072 Anclote River @ Green Brooks Estates 0.0% 45 2

25020013 BOWLEGS CREEK MT PISGAH RD 0.0% 60 1

25020015 PEACE R AT SR64 ZOLFO SPRINGS 18.2% 43 1

25020111 Horse Creek @ SR 72 Bridge 41.9% 70 2

25020291 Troublesome Creek at Dansby Road 0.0% 59 1

25020292 Joshua Creek at airport road 37.4% 47 1

25020293 Peace River @ 664A 16.2% 48 19

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

53 STORET ID Station Description RPS Average

Percent 4 to 6

Scores Mean SCI

2007

Score SCI

2007

(n)

25020294 Charlie creek at Sweetwater Road 6.1% 61 1

25020295 Paynes creek at State Park 12.1% 63 2

25020296 Paynes Creek at Hobbs Road 0.0% 61 1

25020300 Hawthorne Creek at Reynolds 12.1% 59 1

25020423 HORSE CREEK AT SR70 56.6% 57 1

25020427 HORSE CRK AT SR 665 BRDG 8.1% 48 1

25020548 Little Charley Bowlegs Ck, Highlands
Hammock SP 0.0% 46 1

25020550 HOG BAY at CR 763 (S of Arcadia) 12.1% 53 1

25020553 Myrtle Slough

- East Brch Punta G. Ref site 0.0% 56 2

25022977 Charlie Cr upstream of US27. Horse Cr short term study 19.2% 71 1

25022983 Horse Cr,located on Royal Park Estates, south of US72. Horse Cr short term study 18.2% 60 2

25030009 MYAKKA RIVER ABOVE SR 70 BRIDGE 0.0% 59 1

26010430 Fort Drum Creek @ US441 0.5% 49 2

26010614 Carter Creek @ Riverdale Rd 0.0% 72 1

27010050 Moses Creek @ US 1 0.0% 60 1

27010070 STEVENS BR OFF CR 204 SOUTH OF

PELICER CEMETARY 13.1% 76 1

27010337 Horse Creek at Croton Road, Eau Gallie 4.5% 40 2

27010579 Tomoka River @ Eleventh Street Bridge 6.1% 56 3

28010081 LOX R AT TURNPIKE. W OF JUPITER 0.0% 44 2

28020147 HICKEY CREEK 1 MI SOUTH OF SR80 0.0% 52 2

28020155 Bedman Creek at Betts house 0.0% 46 2

31020012 CHIPOLA R HWY 274 CROSS CHIPOLA 0.0% 42 1

32008102 SFTRIB_ARSP 0.5% 53 2

32010066 SHAW STILL BRANCH E COLLEGE DR.

TALL. BASE LINE 18.2% 45 2

32010121 Mill Creek Eglin AFB Golf Course below
17th HoleJAX GRD stream restoration proj. 3.0% 59 2

32010268 Turkey Creek (Bolton) East of Niceville 55.1% 55 2

32020258 Holmes Creek at 276A 0.0% 56 1

32030023 ECONFINA CREEK AT SCOTT RD 1.0% 82 1

33010112 Coffee Cr 1800Ft N of Stiller Lake Rd 0.0% 63 1

33030003 BIG COLDWATER CR E FORK HWY 4 2.0% 72 1

283430821152 Little Withlacoochee River at River

Junction recreation area 0.0% 79 19

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

54 STORET ID Station Description RPS Average

Percent 4 to 6

Scores Mean SCI

2007

Score SCI

2007

(n)

27051558216422 Deer Prairie Slough, on land acquired by Sarasota County 2.0% 74 1

27422738148581 Whidden Cr at Unnamed Rd off of Rt 17/35 1.0% 52 1

27514908208136 N.Prong Alafia at Alderman Ford Park 0.0% 77 1

28152268239035 Pithlachascotee River at Starkey Blvd, upstream of bridge 0.0% 48 2

273116508208152 East Fork Manatee R. S of US62 on Duette Park. Myakka DOSSAC study 0.0% 71 1

28020299FTM BEE BRANCH SITE 2 0.0% 49 1

3598

- B Sampson River 1.0% 65 1

BAK208GS St. Mary's River

- BAK208GS 0.0% 50 1

CHA627GS Alligator Creek

- CHA627GS 0.0% 45 2

CLA243LV Ates Creek

- CLA243LV 0.0% 91 1

CLA246GS Peters Creek

- CLA246GS 0.0% 83 2

CLA254LR Black Creek

- CLA254LR 0.0% 91 1

DEP010C1 Deep Creek @441 0.0% 80 1

FAL020C1 Falling Creek @C

- 131 0.0% 55 1

GAD106GS Yon Creek

- GAD106GS 0.0% 81 1

GLA630GS Cypress Branch

- GLA630GS 0.0% 63 1

HAR610GS Oak Creek

- HAR610GS 1.3% 57 3

LAF176GS Bethel Creek

- LAF176GS 0.0% 61 1

LIB104LV Mule Creek

- LIB104LV 0.0% 67 1

LOCBCC Little Orange Creek below Cabbage 0.0% 89 1

MPS St. Mary's River middle prong 0.0% 71 1

MRN504LR Rainbow River

- MRN504LR 42.4% 62 2

NUTREF001 Telogia Creek at CR 1641 0.0% 78 1

OSC686LV Crabgrass Creek 0.0% 62 1

PUT308GS Little Orange Creek

- PUT308GS 0.0% 75 1

ROB01C1 Robinson Branch @C

- 246 0.0% 81 1

S231 Attapulgus Creek @ 159 0.0% 65 1

S232 Swamp Creek @ 159 0.0% 51 1

SFR030C1 Santa Fe River @ 18 Worthington Springs 0.0% 64 1

SPRINGS006 Wakiwa (Wekiva) R. ab. Rock Spgs run 45.5% 41 1

SSR Silver River above confluence of
Oklawaha River 32.3% 46 1

UNI234LV Olustee Creek

- UNI234LV 0.0% 44 1

WAK168LR St. Marks River

- WAK168LR 15.2% 45 19

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

55 

### Table A

**- 2. List of benchmark streams used to establish RPS and LVS**  **expectations.**

STORET ID Station Description WBID RPS Average

Percent 4 to 6

Scores

3531 S321 Econfina Creek 553 0.0%

3545 S360 Blackwater River @ Hwy 4 24C 4.0%

3546 S365 Yellow River @ Hwy 2 30 0.0%

3549 S377 Escambia River @ HWY 4 Bridge 10C 0.0%

3554 FLO 57 162 0 Alafia River 1621B 28.8%

21201 Moultrie Creek 2493 11.1%

38482 Z1

- LR

- 4004 East Fork Creek 18A 20.2%

38486 Z1

- LR

- 4008 Yellow River 30B 1.0%

38570 Z5

- SS

- 4008 Telegraph Creek 3236A 0.0%

19010006 ST MARYS RIVER AT SR #2 2097K 0.0%

19010041 St Mary's River at CR 125 2211 0.0%

19010076 Calkins Creek at Turner Cemetary Road 2264 0.0%

20030388 PETERS CREEK #2 CULVERT SR 315 2444 0.0%

20030481 South Fork Black Creek @ SR 21 2415E 0.0%

20030920 Mormon Branch upstream of SR 19 in Ocala NF 2905 25.3%

21010008 ALAPAHA RIVER 1 SR 150 HAMILTON 3324 9.1%

22020093 Quincy Creek above SR267 bridge 1303 0.0%

22040009 WASCISSA R #1 AT BIG BLUE SPRING 3424 65.7%

22040041 Wacissa River Bio Site 2 3424 4.0%

22050083 Steinhatchee @ Canal Road 3573A 34.3%

24010002 Manatee R 20 m below SR64 bridge (TP1) 1807C 41.4%

24030044 Hillsborough R in Hills River State Park (TP5) 1443D 3.5%

25030009 MYAKKA RIVER ABOVE SR 70 BRIDGE 1877A 0.0%

26010430 Fort Drum Creek @ US441 3164 0.5%

32030023 ECONFINA CREEK AT SCOTT RD 553 1.0%

33030003 BIG COLDWATER CR E FORK HWY 4 18A 2.0%

27051558216422 Deer Prairie Slough, on land acquired by Sarasota County 1978 2.0%

28020299FTM BEE BRANCH SITE 2 3235E 0.0%

BAK208GS St. Mary's River

- BAK208GS 2097K 0.0%

CLA243LV Ates Creek

- CLA243LV 2498 0.0%

CLA246GS Peters Creek

- CLA246GS 2444 0.0%

DEP010C1 Deep Creek @441 3388 0.0%

GLA630GS Cypress Branch

- GLA630GS 3235G 0.0%

HAR610GS Oak Creek

- HAR610GS 1897 1.3%

LIB104LV Mule Creek

- LIB104LV 684 0.0%9

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

56 STORET ID Station Description WBID RPS Average

Percent 4 to 6

Scores

LOCBCC Little Orange Creek below Cabbage 2713 0.0%

MPS St. Mary's River middle prong 2211 0.0%

NUTREF001 Telogia Creek at CR 1641 1300 0.0%

PUT308GS Little Orange Creek

- PUT308GS 2713 0.0%

ROB01C1 Robinson Branch @C

- 246 3448 0.0%

SFR030C1 Santa Fe River @ 18 Worthington Springs 3605D 0.0%



### Table A

**- 3. List of healthy streams (passing SCI) used to**  **inform stream**  **chlorophyll a expectations.**

WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

4 BRUSHY CREEK 2006 2.2 64

4 BRUSHY CREEK 2007 2.1 64

4 BRUSHY CREEK 2008 1.3 64

4 BRUSHY CREEK 2009 1.1 64

4 BRUSHY CREEK 2010 1.1 64

18 BIG COLDWATER CREEK 2006 3.1 76

18 BIG COLDWATER CREEK 2007 3.2 76

18 BIG COLDWATER CREEK 2008 1.0 76

18 BIG COLDWATER CREEK 2009 1.0 76

18 BIG COLDWATER CREEK 2010 1.0 76

18 BIG COLDWATER CREEK 2011 1.0 76

19 BIG JUNIPER CREEK 2007 3.8 70

24 BLACKWATER RIVER 2009 1.0 68

30 YELLOW RIVER 2006 2.1 70

30 YELLOW RIVER 2007 2.0 70

30 YELLOW RIVER 2008 1.3 70

30 YELLOW RIVER 2009 1.6 70

30 YELLOW RIVER 2010 1.3 70

35 POND CREEK 2007 3.6 78

36 BRAY MILL CREEK 2009 1.0 48

52 COWARTS CREEK 2006 1.0 59

52 COWARTS CREEK 2007 1.0 59

52 COWARTS CREEK 2008 1.0 59

52 COWARTS CREEK 2009 1.3 59

52 COWARTS CREEK 2010 1.2 599

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

57 WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

54 WRIGHTS CREEK 2006 1.0 67

54 WRIGHTS CREEK 2007 1.0 67

54 WRIGHTS CREEK 2008 1.0 67

54 WRIGHTS CREEK 2009 1.0 67

54 WRIGHTS CREEK 2010 1.0 67

59 HOLMES CREEK 2006 1.0 59

59 HOLMES CREEK 2009 1.0 59

72 PERDIDO RIVER (MIDDLE B) 2006 1.8 59

72 PERDIDO RIVER (MIDDLE B) 2007 2.2 59

72 PERDIDO RIVER (MIDDLE B) 2008 1.1 59

72 PERDIDO RIVER (MIDDLE B) 2009 1.1 59

72 PERDIDO RIVER (MIDDLE B) 2010 1.2 59

72 PERDIDO RIVER (MIDDLE B) 2011 1.1 59

87 LITTLE PINE BARREN CREEK 2009 3.2 71

88 MARE CREEK 2009 1.1 73

107 MURDER CREEK 2009 1.2 64

127 MANNING CREEK 2009 1.1 67

149 MCDAVID CREEK 2006 5.6 73

149 MCDAVID CREEK 2010 1.4 73

176 POND CREEK 2007 4.7 81

291 JACKS BRANCH 2010 1.8 42

316 CROOKED CREEK 2009 1.0 44

351 ALAQUA CREEK 2006 1.1 82

351 ALAQUA CREEK 2007 1.0 82

351 ALAQUA CREEK 2008 1.0 82

351 ALAQUA CREEK 2009 1.1 82

351 ALAQUA CREEK 2010 1.0 82

553 ECONFINA CREEK 2006 1.0 75

553 ECONFINA CREEK 2007 1.0 75

553 ECONFINA CREEK 2008 1.0 75

553 ECONFINA CREEK 2009 1.0 75

553 ECONFINA CREEK 2010 1.0 75

684 MULE CREEK 2006 1.9 73

716 CANEY BRANCH 2006 1.9 49

757 BEAR CREEK 2006 2.6 72

896 POLK CREEK 2010 1.0 55

921 HARVEY CREEK 2006 1.9 619

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

58 WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

921 HARVEY CREEK 2010 1.0 61

998 SOPCHOPPY RIVER 2006 2.1 49

1024 BLACK CREEK 2010 1.0 85

1028 MCBRIDE SLOUGH 2006 1.7 57

1300 TELOGIA CREEK 2006 2.1 70

1300 TELOGIA CREEK 2007 1.1 70

1300 TELOGIA CREEK 2008 1.6 70

1300 TELOGIA CREEK 2009 1.0 70

1300 TELOGIA CREEK 2010 1.0 70

1381 LITTLE WITHLACOOCHEE 2008 3.5 56

1381 LITTLE WITHLACOOCHEE 2009 1.8 56

1409 PITHLACHASCOTEE RIVER 2008 4.0 58

1409 PITHLACHASCOTEE RIVER 2010 1.2 58

1431 GATOR CREEK 2008 4.5 54

1431 GATOR CREEK 2009 1.7 54

1431 GATOR CREEK 2010 1.9 54

1436 HORSE (HORSESHOE) CREEK 2009 2.0 60

1436 HORSE (HORSESHOE) CREEK 2010 3.3 60

1482 BLACKWATER CREEK 2010 9.4 64

1583 POLEY CREEK 2008 3.5 44

1639 THIRTYMILE CREEK 2006 1.5 53

1639 THIRTYMILE CREEK 2007 1.3 53

1639 THIRTYMILE CREEK 2008 2.4 53

1688 LITTLE BULLFROG CREEK 2006 1.5 42

1688 LITTLE BULLFROG CREEK 2007 1.3 42

1688 LITTLE BULLFROG CREEK 2009 1.8 42

1790 LITTLE MANATEE RIVER (SOUTH FORK) 2009 1.1 51

1811 MANATEE RIVER (EAST FORK) 2007 1.7 64

1813 CARTER CREEK 2006 8.7 65

1978 DEER PRAIRIE CREEK 2008 2.3 67

1978 DEER PRAIRIE CREEK 2010 1.2 67

1997 HAWTHORNE CREEK 2008 1.9 59

2001 HOG BAY 2007 1.8 50

2001 HOG BAY 2008 2.6 50

2074 ALLIGATOR CREEK 2007 1.4 44

2074 ALLIGATOR CREEK 2008 4.0 44

2196 DEEP CREEK 2008 1.4 499

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

59 WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

2211 MIDDLE PRONG ST MARYS RIVER 2006 1.6 70

2211 MIDDLE PRONG ST MARYS RIVER 2007 1.3 70

2211 MIDDLE PRONG ST MARYS RIVER 2008 1.0 70

2211 MIDDLE PRONG ST MARYS RIVER 2009 1.0 70

2264 CALKINS CREEK 2008 2.6 76

2444 PETERS CREEK 2008 1.4 86

2444 PETERS CREEK 2009 1.5 86

2478 GREENS CREEK 2007 1.3 66

2493 MOULTRIE CREEK 2006 1.3 56

2493 MOULTRIE CREEK 2007 1.3 56

2493 MOULTRIE CREEK 2008 1.1 56

2493 MOULTRIE CREEK 2009 1.0 56

2493 MOULTRIE CREEK 2010 1.2 56

2634 TOMOKA RIVER 2006 1.1 47

2634 TOMOKA RIVER 2007 1.3 47

2634 TOMOKA RIVER 2008 4.2 47

2634 TOMOKA RIVER 2009 2.8 47

2634 TOMOKA RIVER 2010 2.0 47

2634 TOMOKA RIVER 2011 1.3 47

2641 UNNAMED BRANCH 2010 1.5 51

2646 LITTLE TOMOKA RIVER 2010 4.0 50

2673 UNNAMED DRAIN 2010 1.7 47

2675 SAND CREEK 2010 2.8 57

2679 UNNAMED DRAIN 2010 1.0 59

2695 LITTLE HATCHET CREEK 2006 2.2 56

2698 HOGTOWN CREEK 2006 1.3 49

2713 LITTLE ORANGE CREEK 2006 1.5 77

2730 DEEP CREEK RODMAN RESERVOIR 2011 1.1 60

2747 ORANGE CREEK 2006 1.2 78

2747 ORANGE CREEK 2007 1.1 78

2747 ORANGE CREEK 2008 1.0 78

2747 ORANGE CREEK 2009 1.1 78

2747 ORANGE CREEK 2010 1.0 78

2756 MILL CREEK 2010 1.2 65

2987 LITTLE WEKIVA RIVER 2006 2.7 56

2987 LITTLE WEKIVA RIVER 2007 3.9 56

2987 LITTLE WEKIVA RIVER 2009 3.4 569

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

60 WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

2987 LITTLE WEKIVA RIVER 2010 1.5 56

2991 ECONLOCKHATCHEE RIVER 2006 1.1 62

2991 ECONLOCKHATCHEE RIVER 2007 1.2 62

2991 ECONLOCKHATCHEE RIVER 2008 1.1 62

2997 HOWELL CREEK BELOW LAKE

HOWELL 2009 6.2 55

2999 BEAR CREEK 2009 1.8 52

3073 CRABGRASS CREEK 2007 1.5 62

3081 HORSE CREEK 2006 2.4 42

3081 HORSE CREEK 2007 2.5 42

3081 HORSE CREEK 2008 3.1 42

3164 FORT DRUM CREEK 2008 17.2 48

3324 ALAPAHA RIVER 2006 1.2 54

3324 ALAPAHA RIVER 2007 1.6 54

3324 ALAPAHA RIVER 2008 1.6 54

3324 ALAPAHA RIVER 2009 1.1 54

3324 ALAPAHA RIVER 2010 1.3 54

3325 ALLIGATOR CREEK 2006 1.3 69

3330 LITTLE ALAPAHA RIVER 2006 1.3 44

3351 ROCKY CREEK NEAR BENTON 2006 1.1 59

3351 ROCKY CREEK NEAR BENTON 2007 2.3 59

3351 ROCKY CREEK NEAR BENTON 2010 1.0 59

3388 DEEP CREEK 2006 1.5 78

3401 CAMP BRANCH 2010 3.2 55

3402 ECONFINA RIVER 2006 1.1 51

3402 ECONFINA RIVER 2007 2.4 51

3402 ECONFINA RIVER 2008 1.4 51

3402 ECONFINA RIVER 2009 1.0 51

3402 ECONFINA RIVER 2010 1.0 51

3422 SUWANNEE RIVER (LOWER SEGMENT) 2006 1.2 48

3448 ROBINSON CREEK 2006 1.4 81

3480 BETHEL CREEK 2006 1.0 54

3506 NEW RIVER 2010 2.2 73

3598 SAMPSON RIVER 2010 1.7 69

3649 COW CREEK 2006 2.6 69

3649 COW CREEK 2007 1.9 69

3649 COW CREEK 2010 1.4 699

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

61 WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

3699 WACCASASSA RIVER 2007 3.0 75

3699 WACCASASSA RIVER 2008 2.6 75

3699 WACCASASSA RIVER 2009 2.1 75

3731 WEKIVA RIVER 2009 1.0 71

1320B RAINBOW SPRINGS GROUP RUN 2006 1.0 58

1320B RAINBOW SPRINGS GROUP RUN 2007 1.0 58

1320B RAINBOW SPRINGS GROUP RUN 2008 1.0 58

1320B RAINBOW SPRINGS GROUP RUN 2009 1.0 58

1320B RAINBOW SPRINGS GROUP RUN 2010 1.0 58

1351A OUTLET RIVER 2010 11.8 43

1443D HILLSBOROUGH RIVER 2008 2.2 61

1443D HILLSBOROUGH RIVER 2009 1.2 61

1495A ITCHEPACKESASSA CREEK 2007 1.9 49

1495A ITCHEPACKESASSA CREEK 2008 9.8 49

1495B ITCHEPACKESASSA CREEK 2008 3.1 58

1573D WEOHYAKAPKA CREEK 2010 6.2 56

1592C MUSTANG RANCH CREEK 2010 2.6 59

160B SHOAL RIVER 2007 2.9 84

1621A ALAFIA RIVER ABOVE

HILLSBOROUGH BAY 2009 3.5 41

1621B ALAFIA RIVER ABOVE FLINT HAWK 2006 2.1 57

1621B ALAFIA RIVER ABOVE FLINT HAWK 2007 2.0 57

1621B ALAFIA RIVER ABOVE FLINT HAWK 2008 1.7 57

1621B ALAFIA RIVER ABOVE FLINT HAWK 2009 3.2 57

1621B ALAFIA RIVER ABOVE FLINT HAWK 2010 3.5 57

1621D ALAFIA RIVER (NORTH PRONG)

LOWER SEGMENT 2008 1.6 63

1621D ALAFIA RIVER (NORTH PRONG)

LOWER SEGMENT 2009 1.6 63

1685B LIVINGSTON CREEK 2006 19.0 65

1685B LIVINGSTON CREEK 2007 6.4 65

1685B LIVINGSTON CREEK 2008 11.8 65

1685B LIVINGSTON CREEK 2009 4.4 65

1685B LIVINGSTON CREEK 2010 3.3 65

1742B LITTLE MANATEE RIVER (NORTH FORK) 2006 1.5 46

1757A PAYNE CREEK (LOWER SEGMENT) 2008 1.1 59

1757A PAYNE CREEK (LOWER SEGMENT) 2009 2.8 599

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

62 WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

1757B PAYNE CREEK (UPPER SEGMENT) 2007 1.3 62

1757B PAYNE CREEK (UPPER SEGMENT) 2008 1.1 62

1787B HORSE CREEK ABOVE BUSHY CREEK 2007 1.0 66

1807C MANATEE RIVER 2007 1.4 72

1877A MYAKKA RIVER (UPPER SEGMENT) 2006 1.2 43

1877A MYAKKA RIVER (UPPER SEGMENT) 2007 1.4 43

1877A MYAKKA RIVER (UPPER SEGMENT) 2008 1.5 43

1877A MYAKKA RIVER (UPPER SEGMENT) 2010 1.8 43

18A EAST FORK 2007 3.0 70

18A EAST FORK 2009 1.1 70

2097H ST MARYS RIVER 2007 2.3 55

2097K ST MARYS RIVER (NORTH PRONG) 2006 1.2 57

2097K ST MARYS RIVER (NORTH PRONG) 2007 1.2 57

2097K ST MARYS RIVER (NORTH PRONG) 2008 1.3 57

2386A BLACK CREEK (NORTH FORK) 2006 1.7 56

2386A BLACK CREEK (NORTH FORK) 2007 1.4 56

2386A BLACK CREEK (NORTH FORK) 2008 1.1 56

2386A BLACK CREEK (NORTH FORK) 2009 1.3 56

2386A BLACK CREEK (NORTH FORK) 2010 1.4 56

2415C BLACK CREEK (SOUTH FORK) 2008 1.2 91

24D BLACKWATER RIVER 2007 1.6 65

2535B MOSES CREEK (FRESHWATER SEGMENT) 2008 1.2 63

2740C OCKLAWAHA RIVER ABOVE LAKE

OCKLAWAHA 2006 1.5 63

2740C OCKLAWAHA RIVER ABOVE LAKE

OCKLAWAHA 2007 1.6 63

2740C OCKLAWAHA RIVER ABOVE LAKE

OCKLAWAHA 2008 1.2 63

2740C OCKLAWAHA RIVER ABOVE LAKE

OCKLAWAHA 2009 1.2 63

2740C OCKLAWAHA RIVER ABOVE LAKE

OCKLAWAHA 2010 1.4 63

2740C OCKLAWAHA RIVER ABOVE LAKE

OCKLAWAHA 2011 1.2 63

2772D SILVER RIVER (LOWER) 2006 1.8 54

2772D SILVER RIVER (LOWER) 2007 1.1 54

2772D SILVER RIVER (LOWER) 2008 1.0 54

2772D SILVER RIVER (LOWER) 2009 1.1 549

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

63 WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

2929A BLACK WATER CREEK 2006 1.1 54

2929A BLACK WATER CREEK 2007 1.4 54

2929A BLACK WATER CREEK 2008 1.2 54

2929A BLACK WATER CREEK 2009 1.3 54

2929A BLACK WATER CREEK 2010 1.2 54

2987B LITTLE WEKIVA (WEST) 2008 5.8 46

2991A ECONLOCKHATCHEE RIVER 2007 1.6 50

2991A ECONLOCKHATCHEE RIVER 2009 1.0 50

2991A ECONLOCKHATCHEE RIVER 2010 1.1 50

30A YELLOW RIVER 2007 1.6 54

30A YELLOW RIVER 2008 1.2 54

3169A SHINGLE CREEK 2007 1.2 50

3169A SHINGLE CREEK 2008 1.1 50

3169A SHINGLE CREEK 2009 1.6 50

3170D2 BONNET CREEK SOUTH 2009 7.8 44

3224C CYPRESS CREEK 2011 2.3 44

3235E BEE BRANCH 2008 2.8 49

3235H HICKEY CREEK 2006 2.5 50

3235H HICKEY CREEK 2007 3.6 50

3235H HICKEY CREEK 2008 4.2 50

3235H HICKEY CREEK 2009 1.7 50

3235I BEDMAN CREEK 2006 1.7 49

3235I BEDMAN CREEK 2007 2.1 49

3235I BEDMAN CREEK 2008 1.6 49

3235I BEDMAN CREEK 2009 1.3 49

3235I BEDMAN CREEK 2010 1.1 49

3236A TELEGRAPH CREEK 2006 2.0 59

3236A TELEGRAPH CREEK 2007 2.0 59

3236A TELEGRAPH CREEK 2008 3.0 59

3236A TELEGRAPH CREEK 2009 2.9 59

3236A TELEGRAPH CREEK 2010 1.8 59

3240F DAUGHTREY CREEK 2006 2.0 55

3240F DAUGHTREY CREEK 2007 5.2 55

3240F DAUGHTREY CREEK 2008 4.1 55

3240F DAUGHTREY CREEK 2009 2.4 55

3240F DAUGHTREY CREEK 2010 2.4 55

3240F DAUGHTREY CREEK 2011 3.3 559

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

64 WBID Basin Year Geometric
mean Chl

- a (μg/L) Mean SCI

2007

3240K ORANGE RIVER 2006 2.0 41

3341A SUWANNEE RIVER (UPPER SEGMENT) 2008 1.7 58

3341C SUWANNEE RIVER (UPPER SEGMENT) 2006 1.3 48

3422P MEARSON SPRING 2006 1.5 54

3504A OLUSTEE CREEK 2006 2.2 53

3504A OLUSTEE CREEK 2007 5.0 53

3504A OLUSTEE CREEK 2010 1.2 53

3598C ALLIGATOR CREEK 2006 1.1 41

49F CHOCTAWHATCHEE RIVER 2006 1.2 57

49F CHOCTAWHATCHEE RIVER 2007 1.6 57

49F CHOCTAWHATCHEE RIVER 2008 1.5 57

49F CHOCTAWHATCHEE RIVER 2009 1.6 57

49F CHOCTAWHATCHEE RIVER 2010 2.2 57

72D PERDIDO RIVER (MIDDLE A) 2008 1.1 56

791L LAKE MICCOSUKEE OUTLET 2010 2.6 52



### Table A

**- 4. List of benchmark streams used to**  **establish stream chlorophyll a**  **expectations.**

WBID Basin Year Geometric mean
Chl

- a (μg/L)

24 BLACKWATER RIVER 1998 5.0

24 BLACKWATER RIVER 2009 1.0

30 YELLOW RIVER 2000 1.2

30 YELLOW RIVER 2001 1.1

30 YELLOW RIVER 2002 1.0

30 YELLOW RIVER 2003 1.6

30 YELLOW RIVER 2004 1.9

30 YELLOW RIVER 2005 2.5

30 YELLOW RIVER 2006 2.1

30 YELLOW RIVER 2007 2.0

30 YELLOW RIVER 2008 1.3

30 YELLOW RIVER 2009 1.6

30 YELLOW RIVER 2010 1.3

30 YELLOW RIVER 2010 1.49

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

65 WBID Basin Year Geometric mean
Chl

- a (μg/L)

149 MCDAVID CREEK 2005 3.5

149 MCDAVID CREEK 2006 5.6

149 MCDAVID CREEK 2010 1.4

279 DRY CREEK 2005 1.2

279 DRY CREEK 2007 1.2

397 UNNAMED RUN 2005 2.2

504 CROOKED CREEK 2005 1.4

553 ECONFINA CREEK 2000 1.0

553 ECONFINA CREEK 2001 1.0

553 ECONFINA CREEK 2002 1.0

553 ECONFINA CREEK 2003 1.0

553 ECONFINA CREEK 2004 1.0

553 ECONFINA CREEK 2005 1.0

553 ECONFINA CREEK 2006 1.0

553 ECONFINA CREEK 2007 1.0

553 ECONFINA CREEK 2008 1.0

553 ECONFINA CREEK 2009 1.0

553 ECONFINA CREEK 2009 1.0

553 ECONFINA CREEK 2010 1.0

569 TENMILE CREEK 2002 1.1

569 TENMILE CREEK 2007 1.1

679 BLACK CREEK 2008 1.7

684 MULE CREEK 2005 1.2

684 MULE CREEK 2006 1.9

718 FOURMILE CREEK 2002 1.0

718 FOURMILE CREEK 2007 1.1

749 JUNIPER CREEK 2007 1.4

889 MOORE LAKE DRAIN 2008 1.6

889 MOORE LAKE DRAIN 2010 1.0

998 SOPCHOPPY RIVER 2004 1.0

998 SOPCHOPPY RIVER 2005 1.2

998 SOPCHOPPY RIVER 2006 2.1

1240 FORT GADSDEN CREEK 2007 2.7

1300 TELOGIA CREEK 1999 1.0

1300 TELOGIA CREEK 2000 1.6

1300 TELOGIA CREEK 2001 1.1

1300 TELOGIA CREEK 2002 1.0

1300 TELOGIA CREEK 2003 1.09

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

66 WBID Basin Year Geometric mean
Chl

- a (μg/L)

1300 TELOGIA CREEK 2004 1.1

1300 TELOGIA CREEK 2005 1.1

1300 TELOGIA CREEK 2006 2.1

1300 TELOGIA CREEK 2007 1.1

1300 TELOGIA CREEK 2008 1.6

1300 TELOGIA CREEK 2009 1.0

1300 TELOGIA CREEK 2010 1.0

1303 QUINCY CREEK (POTABLE PORTION) 2005 3.0

1303 QUINCY CREEK (POTABLE PORTION) 2006 2.5

1454 FISH HATCHERY DRAIN 2007 1.3

1658 FISHHAWK CREEK 2005 2.0

1658 FISHHAWK CREEK 2006 1.6

1658 FISHHAWK CREEK 2007 3.4

1658 FISHHAWK CREEK 2008 1.7

1658 FISHHAWK CREEK 2009 1.6

1658 FISHHAWK CREEK 2010 4.4

1666 BULLFROG CREEK 1998 2.9

1666 BULLFROG CREEK 1999 1.8

1666 BULLFROG CREEK 2000 2.3

1666 BULLFROG CREEK 2001 3.8

1666 BULLFROG CREEK 2002 2.2

1666 BULLFROG CREEK 2003 1.3

1666 BULLFROG CREEK 2004 1.6

1666 BULLFROG CREEK 2005 2.0

1666 BULLFROG CREEK 2006 2.0

1666 BULLFROG CREEK 2007 1.8

1666 BULLFROG CREEK 2008 1.7

1666 BULLFROG CREEK 2009 1.8

1666 BULLFROG CREEK 2010 2.7

1686 UNNAMED CREEK 2006 4.3

1897 OAK CREEK 2005 1.5

1978 DEER PRAIRIE CREEK 1998 2.8

1978 DEER PRAIRIE CREEK 1999 2.2

1978 DEER PRAIRIE CREEK 2000 2.0

1978 DEER PRAIRIE CREEK 2001 1.7

1978 DEER PRAIRIE CREEK 2002 4.9

1978 DEER PRAIRIE CREEK 2003 1.7

1978 DEER PRAIRIE CREEK 2004 2.29

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

67 WBID Basin Year Geometric mean
Chl

- a (μg/L)

1978 DEER PRAIRIE CREEK 2005 1.3

1978 DEER PRAIRIE CREEK 2006 1.4

1978 DEER PRAIRIE CREEK 2007 2.4

1978 DEER PRAIRIE CREEK 2008 2.3

1978 DEER PRAIRIE CREEK 2010 1.2

2105 PIGEON CREEK 2008 1.4

2161 THOMAS CREEK 2001 1.0

2161 THOMAS CREEK 2008 1.5

2196 DEEP CREEK 2008 1.4

2211 MIDDLE PRONG ST MARYS RIVER 1996 1.3

2211 MIDDLE PRONG ST MARYS RIVER 1997 1.3

2211 MIDDLE PRONG ST MARYS RIVER 1998 1.0

2211 MIDDLE PRONG ST MARYS RIVER 1999 1.4

2211 MIDDLE PRONG ST MARYS RIVER 2000 1.3

2211 MIDDLE PRONG ST MARYS RIVER 2001 1.3

2211 MIDDLE PRONG ST MARYS RIVER 2002 1.3

2211 MIDDLE PRONG ST MARYS RIVER 2003 1.1

2211 MIDDLE PRONG ST MARYS RIVER 2004 1.2

2211 MIDDLE PRONG ST MARYS RIVER 2005 1.0

2211 MIDDLE PRONG ST MARYS RIVER 2006 1.6

2211 MIDDLE PRONG ST MARYS RIVER 2007 1.3

2211 MIDDLE PRONG ST MARYS RIVER 2008 1.0

2211 MIDDLE PRONG ST MARYS RIVER 2009 1.0

2264 CALKINS CREEK 2008 2.6

2407 GROG BRANCH 2007 1.1

2444 PETERS CREEK 1996 2.8

2444 PETERS CREEK 1997 3.1

2444 PETERS CREEK 1998 2.6

2444 PETERS CREEK 1999 2.7

2444 PETERS CREEK 2000 2.4

2444 PETERS CREEK 2001 3.2

2444 PETERS CREEK 2002 2.7

2444 PETERS CREEK 2003 2.3

2444 PETERS CREEK 2004 2.2

2444 PETERS CREEK 2005 1.5

2444 PETERS CREEK 2006 2.4

2444 PETERS CREEK 2007 1.4

2444 PETERS CREEK 2008 1.49

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

68 WBID Basin Year Geometric mean
Chl

- a (μg/L)

2444 PETERS CREEK 2009 1.5

2444 PETERS CREEK 2010 1.7

2444 PETERS CREEK 2011 2.3

2478 GREENS CREEK 2004 1.0

2478 GREENS CREEK 2007 1.3

2493 MOULTRIE CREEK 1996 1.2

2493 MOULTRIE CREEK 1997 0.8

2493 MOULTRIE CREEK 1998 0.7

2493 MOULTRIE CREEK 1999 1.5

2493 MOULTRIE CREEK 2000 2.2

2493 MOULTRIE CREEK 2001 1.4

2493 MOULTRIE CREEK 2002 1.1

2493 MOULTRIE CREEK 2003 1.0

2493 MOULTRIE CREEK 2004 1.1

2493 MOULTRIE CREEK 2005 1.4

2493 MOULTRIE CREEK 2006 1.3

2493 MOULTRIE CREEK 2007 1.3

2493 MOULTRIE CREEK 2008 1.1

2493 MOULTRIE CREEK 2009 1.0

2493 MOULTRIE CREEK 2010 1.2

2498 ATES CREEK 2005 1.0

2500 UNNAMED BRANCH 2002 1.0

2713 LITTLE ORANGE CREEK 1997 1.0

2713 LITTLE ORANGE CREEK 1998 1.0

2713 LITTLE ORANGE CREEK 2000 1.0

2713 LITTLE ORANGE CREEK 2005 1.1

2713 LITTLE ORANGE CREEK 2006 1.5

2905 JUNIPER CREEK 2005 1.2

2905 JUNIPER CREEK 2008 0.7

2905 JUNIPER CREEK 2009 0.7

2905 JUNIPER CREEK 2010 0.9

3035 TOOTOOSAHATCHEE CREEK 2005 1.0

3035 TOOTOOSAHATCHEE CREEK 2008 1.9

3042 JIM CREEK 2008 1.4

3086 CRABGRASS CREEK (WEST BRANCH) 2003 3.3

3086 CRABGRASS CREEK (WEST BRANCH) 2008 1.0

3164 FORT DRUM CREEK 2008 17.2

3324 ALAPAHA RIVER 2000 1.09

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

69 WBID Basin Year Geometric mean
Chl

- a (μg/L)

3324 ALAPAHA RIVER 2001 1.0

3324 ALAPAHA RIVER 2002 1.1

3324 ALAPAHA RIVER 2003 1.2

3324 ALAPAHA RIVER 2004 1.2

3324 ALAPAHA RIVER 2005 1.3

3324 ALAPAHA RIVER 2006 1.2

3324 ALAPAHA RIVER 2007 1.6

3324 ALAPAHA RIVER 2008 1.6

3324 ALAPAHA RIVER 2009 1.1

3324 ALAPAHA RIVER 2010 1.3

3351 ROCKY CREEK NEAR BENTON 2006 1.1

3351 ROCKY CREEK NEAR BENTON 2007 2.3

3351 ROCKY CREEK NEAR BENTON 2010 1.0

3388 DEEP CREEK 1998 1.6

3388 DEEP CREEK 2006 1.5

3448 ROBINSON CREEK 2006 1.4

3480 BETHEL CREEK 2006 1.0

3605 SANTA FE RIVER 2010 1.0

10C ESCAMBIA RIVER 2000 1.0

10C ESCAMBIA RIVER 2001 1.1

10C ESCAMBIA RIVER 2002 1.1

10C ESCAMBIA RIVER 2003 1.6

10C ESCAMBIA RIVER 2004 1.3

10C ESCAMBIA RIVER 2005 2.2

10C ESCAMBIA RIVER 2006 1.8

10C ESCAMBIA RIVER 2007 2.2

10C ESCAMBIA RIVER 2008 1.9

10C ESCAMBIA RIVER 2009 1.8

10C ESCAMBIA RIVER 2010 2.0

1329D WITHLACOOCHEE RIVER 2000 2.1

1329D WITHLACOOCHEE RIVER 2001 2.1

1329D WITHLACOOCHEE RIVER 2002 4.0

1329D WITHLACOOCHEE RIVER 2003 2.5

1329D WITHLACOOCHEE RIVER 2004 3.9

1329D WITHLACOOCHEE RIVER 2005 5.2

1329D WITHLACOOCHEE RIVER 2006 4.7

1329D WITHLACOOCHEE RIVER 2007 6.5

1329D WITHLACOOCHEE RIVER 2008 7.59

- 14

- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

70 WBID Basin Year Geometric mean
Chl

- a (μg/L)

1329D WITHLACOOCHEE RIVER 2009 11.5

1329E WITHLACOOCHEE RIVER 2000 4.2

1329E WITHLACOOCHEE RIVER 2001 3.0

1329E WITHLACOOCHEE RIVER 2002 3.7

1329E WITHLACOOCHEE RIVER 2003 2.1

1329E WITHLACOOCHEE RIVER 2004 4.0

1329E WITHLACOOCHEE RIVER 2005 2.3

1329E WITHLACOOCHEE RIVER 2006 4.3

1329E WITHLACOOCHEE RIVER 2007 9.0

1329E WITHLACOOCHEE RIVER 2008 7.7

1329E WITHLACOOCHEE RIVER 2009 7.3

1351A OUTLET RIVER 2001 3.1

1351A OUTLET RIVER 2002 5.5

1351A OUTLET RIVER 2003 15.6

1351A OUTLET RIVER 2004 7.1

1443D HILLSBOROUGH RIVER 2005 1.2

1443D HILLSBOROUGH RIVER 2006 1.0

1443D HILLSBOROUGH RIVER 2007 1.4

1443D HILLSBOROUGH RIVER 2008 2.2

1443D HILLSBOROUGH RIVER 2009 1.2

1495A ITCHEPACKESASSA CREEK 2007 1.9

1495A ITCHEPACKESASSA CREEK 2008 9.8

160B SHOAL RIVER 2005 2.5

160B SHOAL RIVER 2006 5.0

160B SHOAL RIVER 2007 2.9

160B SHOAL RIVER 2009 1.6

1621B ALAFIA RIVER ABOVE FLINT HAWK 2000 1.0

1621B ALAFIA RIVER ABOVE FLINT HAWK 2001 1.2

1621B ALAFIA RIVER ABOVE FLINT HAWK 2002 1.2

1621B ALAFIA RIVER ABOVE FLINT HAWK 2003 1.2

1621B ALAFIA RIVER ABOVE FLINT HAWK 2004 1.0

1621B ALAFIA RIVER ABOVE FLINT HAWK 2005 2.6

1621B ALAFIA RIVER ABOVE FLINT HAWK 2006 2.1

1621B ALAFIA RIVER ABOVE FLINT HAWK 2007 2.0

1621B ALAFIA RIVER ABOVE FLINT HAWK 2008 1.7

1621B ALAFIA RIVER ABOVE FLINT HAWK 2009 3.2

1621B ALAFIA RIVER ABOVE FLINT HAWK 2010 3.5

1742B LITTLE MANATEE RIVER (NORTH 2005 1.89

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- 12 Document Submitted to EPA in Support of the Department’s Adopted Nutrient Standards

71 WBID Basin Year Geometric mean
Chl

- a (μg/L) FORK)

1742B LITTLE MANATEE RIVER (NORTH FORK) 2006 1.5

1742B LITTLE MANATEE RIVER (NORTH FORK) 2007 1.2

1742B LITTLE MANATEE RIVER (NORTH FORK) 2008 1.8

1742B LITTLE MANATEE RIVER (NORTH FORK) 2009 1.4

1807C MANATEE RIVER 2007 1.4

1869C MYAKKA RIVER (UPPER SEGMENT) 1999 2.4

1877A MYAKKA RIVER (UPPER SEGMENT) 1998 3.2

1877A MYAKKA RIVER (UPPER SEGMENT) 1999 1.6

1877A MYAKKA RIVER (UPPER SEGMENT) 2000 1.2

1877A MYAKKA RIVER (UPPER SEGMENT) 2001 1.0

1877A MYAKKA RIVER (UPPER SEGMENT) 2002 1.8

1877A MYAKKA RIVER (UPPER SEGMENT) 2003 1.3

1877A MYAKKA RIVER (UPPER SEGMENT) 2004 1.2

1877A MYAKKA RIVER (UPPER SEGMENT) 2005 1.4

1877A MYAKKA RIVER (UPPER SEGMENT) 2006 1.2

1877A MYAKKA RIVER (UPPER SEGMENT) 2007 1.4

1877A MYAKKA RIVER (UPPER SEGMENT) 2008 1.5

1877A MYAKKA RIVER (UPPER SEGMENT) 2010 1.8

18A EAST FORK 2005 5.0

18A EAST FORK 2006 5.0

18A EAST FORK 2007 3.0

18A EAST FORK 2009 1.1

2097K ST MARYS RIVER (NORTH PRONG) 1996 1.2

2097K ST MARYS RIVER (NORTH PRONG) 1997 1.9

2097K ST MARYS RIVER (NORTH PRONG) 1998 1.1

2097K ST MARYS RIVER (NORTH PRONG) 1999 3.2

2097K ST MARYS RIVER (NORTH PRONG) 2000 1.3

2097K ST MARYS RIVER (NORTH PRONG) 2001 1.1

2097K ST MARYS RIVER (NORTH PRONG) 2002 1.6

2097K ST MARYS RIVER (NORTH PRONG) 2003 1.0

2097K ST MARYS RIVER (NORTH PRONG) 2004 1.5

2097K ST MARYS RIVER (NORTH PRONG) 2005 1.0

2097K ST MARYS RIVER (NORTH PRONG) 2006 1.2

2097K ST MARYS RIVER (NORTH PRONG) 2007 1.29

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72 WBID Basin Year Geometric mean
Chl

- a (μg/L)

2097K ST MARYS RIVER (NORTH PRONG) 2008 1.3

2097K ST MARYS RIVER (NORTH PRONG) 2009 1.0

2120B MILLS CREEK 2008 1.8

2415E BLACK CREEK (SOUTH FORK) 2005 1.0

24C BLACKWATER RIVER 2000 1.0

24C BLACKWATER RIVER 2001 1.1

24C BLACKWATER RIVER 2002 1.1

24C BLACKWATER RIVER 2003 1.0

24C BLACKWATER RIVER 2004 1.1

24C BLACKWATER RIVER 2005 1.1

24C BLACKWATER RIVER 2006 1.0

24C BLACKWATER RIVER 2007 1.1

24C BLACKWATER RIVER 2008 1.1

24C BLACKWATER RIVER 2009 1.1

24C BLACKWATER RIVER 2010 1.1

2551A LAKE TRIPLET DRAIN 2005 1.2

2929A BLACK WATER CREEK 1996 1.3

2929A BLACK WATER CREEK 1997 1.1

2929A BLACK WATER CREEK 1998 0.2

2929A BLACK WATER CREEK 1999 1.1

2929A BLACK WATER CREEK 2000 1.0

2929A BLACK WATER CREEK 2001 1.2

2929A BLACK WATER CREEK 2002 1.0

2929A BLACK WATER CREEK 2003 1.0

2929A BLACK WATER CREEK 2004 1.9

2929A BLACK WATER CREEK 2005 1.3

2929A BLACK WATER CREEK 2006 1.1

2929A BLACK WATER CREEK 2007 1.4

2929A BLACK WATER CREEK 2008 1.2

2929A BLACK WATER CREEK 2009 1.3

2929A BLACK WATER CREEK 2010 1.2

2929A BLACK WATER CREEK 2011 1.0

30B YELLOW RIVER 2003 1.0

3235E BEE BRANCH 2005 1.3

3235E BEE BRANCH 2008 2.8

3235G CYPRESS BRANCH 2005 3.2

3236A TELEGRAPH CREEK 1999 1.2

3236A TELEGRAPH CREEK 2000 3.39

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73 WBID Basin Year Geometric mean
Chl

- a (μg/L)

3236A TELEGRAPH CREEK 2001 1.4

3236A TELEGRAPH CREEK 2002 1.4

3236A TELEGRAPH CREEK 2003 1.6

3236A TELEGRAPH CREEK 2004 1.9

3236A TELEGRAPH CREEK 2005 2.3

3236A TELEGRAPH CREEK 2006 2.0

3236A TELEGRAPH CREEK 2007 2.0

3236A TELEGRAPH CREEK 2008 3.0

3236A TELEGRAPH CREEK 2009 2.9

3236A TELEGRAPH CREEK 2010 1.8

3236A TELEGRAPH CREEK 2011 2.1

3310Z NUTALL RISE SPRING 2006 1.7

3310Z NUTALL RISE SPRING 2007 1.0

3506B NEW RIVER 2010 2.0

3506B NEW RIVER 2011 1.5

3573A STEINHATCHEE RIVER 2002 1.0

3573A STEINHATCHEE RIVER 2006 1.6

3573A STEINHATCHEE RIVER 2011 1.0

3605D SANTA FE RIVER 2001 1.6

375G APALACHICOLA RIVER 2001 1.2

375G APALACHICOLA RIVER 2005 3.7

375G APALACHICOLA RIVER 2007 1.4

793Z HORN SPRING 2006 1.6

793Z HORN SPRING 2007 1.09

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74 

## Appendix B

. Department’s Algal Bioassessment and Autecological References, 2012

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. Autecology of Freshwater Algae: Datafiles and Links to Internet Resources. Patrick Center for
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— Applications for the environmental and earth sciences: Cambridge, U.K., Cambridge University Press, p. 85

– 127. Berkman, J.A.H., and Po rter, S.D. 2004. An overview of algal monitoring and research in the U.S. Geological Survey’s National Water Quality Assessment (NAWQA) Program: Diatom, v. 20, p.

13

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stress

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