Preliminary Report (DRAFT)

For Project Entitled 

Nutrient Loading Rates, Reduction Factors and 

Implementation Costs Associated with BMPs and 

Technologies 

Prepared for 

South Florida Water Management District 

by 

Soil and Water Engineering Technology, Inc. 

First Revision 

May 8, 2008 
2

INTRODUCTION 

The South Florida Water Management District (SFWMD), in cooperation with the Florida 

Department of Environmental Protection (FDEP) and the Florida Department of Agriculture and 

Consumer Services (FDACS), is developing the Protection Plans for both Caloosahatchee River 

(C-43) and St. Lucie River (C-44) watersheds as required by the Northern Everglades and 

Estuaries Protection Program (Senate Bill 392). The plans will be developed partially based on a 

nutrient reduction spreadsheet approach detailing how water quality standards, including 

phosphorus and nitrogen, will be met. The spreadsheet provides load reduction estimates 

resulting from Best Management Practices (BMPs), as well as local and regional projects. The 

letter report titled "Phosphorus Reduction Performance and Implementation Costs under BMPs 

and Technologies in the Lake Okeechobee Protection Plan Area” provides only part of the input 

data needed for the BMP spreadsheet for these additional watersheds. Therefore the overall 

objectives of this project are to: 1) develop nutrient (nitrogen and phosphorus) loading rates, 

BMP reduction factors and implementation costs for both C-43 and C-44 watersheds; and 2) 

conduct a detailed literature review and data analysis to quantify the BMP effectiveness for each 

commodity and soil type statewide. 

This draft report summarizes the efforts to date for completing the first task. 

METHODOLOGY AND RESULTS 

The approach taken for developing the nutrient reduction spreadsheets for C-43 and C-44 was to 

update the previously developed spreadsheets for the Okeechobee watershed using the additional 

literature data, land use data, observed flow and nutrient load data, and information from 

watershed modeling project for the two watersheds. The SFWMD provided the land use 

breakdown for the two watersheds for twenty major land use categories, which included the six 

new land use categories (low density residential, medium density residential, high density 

residential, horse farms, transportation, and utilities. The following section describes how these 

data were used to develop the final unit nutrient load and BMP reduction spreadsheets. Though 

the methodology was very similar for both the Caloosahatchee and the St. Lucie watersheds, they 

are both included in order to highlight data sources and verification differences. 

St. Lucie River Watershed 

Figure 1 shows the basins within the St. Lucie River watershed. The 2004 land use distribution 

for this watershed was provided by SFWMD and is presented in Table 1. As can be seen, the 

table provides additional land use breakdowns beyond the twenty primary land use categories 

required for the project. These additional data were used during the development of the unit 

loads, but were integrated within the twenty categories for the final tables to prevent confusion. 

Measured data were provided by the SFWMD as presented in Table 2 which compared to data 

obtained from the CERP System-wide Performance Measure Documentation Sheet (April 5, 

2007). 

The initial estimates of the unit nutrient loads were developed from the Okeechobee Basin data 

provided in the BMP Letter Report (Bottcher, 2006), general Florida estimates by Harper and 
3

Baker (2003 and 2007), and data collected within the basin by Graves, et al (2004). The final N 

and P unit loads for the watershed presented in Table 3 were developed as an iterative process 

starting with the initial unit loads estimates linked to a basin spreadsheet where the accumulative 

N and P loads from each basin could be calculated by multiplying the land use acreage by the 

unit loads. The net N and P loads were then compared to the measured basin and basin loads to 

verify if the net loads were at least in the ballpark and how the calculated and measured N and P 

loads for each of the basins compared. It was clear that the dominant land uses in the western 

basins were improved pasture and citrus while the eastern basins were much more residential and 

urban. Using this cross information it was possible to estimate the relative importance of the 

various land uses and adjustments were made accordingly to obtain a reasonable agreement of 

runoff and nutrient loads and concentrations for each of the basins. However, it was observed 

that there was a potential problem using the measured flow data for net load estimates because of 

the high runoff variability between basins as seen in Table 2 for the annual runoff in terms of 

inches per year. Therefore, the cross basin comparisons focused more on matching the 

concentrations because they would be less influenced by any flow errors that might be the result 

of unmeasured inter-basin transfers. Since the unit loads are a function of both concentration and 

flow, it was first necessary to establish reasonable runoff coefficients for the various land uses 

(Harper and Baker, 2007). The resulting annual average runoff for the various land uses are 

provided in Table 3. Tables 3 also provides the resulting N and P unit loads and concentrations 

from the iterative process of adjusting individual land use unit loads which multiplied by the 

acreage of each land use within the basins (Table 4) to obtain reasonable basin runoff (Table 5), 

P loads (Table 6), and N loads (Table 7) comparison to observed data. The P unit load factors 

were adjusted individually based on best professional judgment. The N unit loads were also 

initially adjusted individually, but then a global multiplier factor was used to obtain reasonable 

matches to observed data. The verification for the N and P concentrations are also provided in 

Tables 6 and 7, respectively at the bottom of the tables. Note that the net calculated loads are 

slightly higher than observed data because these represent net source loads which do not reflect 

the additional assimilation that is expected in the stream and canals before reaching the basin 

outlets. 

 

The next step was to establish BMP N and P reduction estimates for the C-44 basin. This was 

done by adding BMP reduction estimates for the six additional land use categories to the BMP 

reduction spreadsheets developed by Bottcher (2006). The resulting BMP reduction estimates 

and costs for N and P are presented in Appendix A. These tables reflect the updated unit loads 

provided in Tables 6 and 7. Table 8 provides a summary of the P unit loads and estimated BMP 

reduction factors for the three categories of owner implemented, typical incentive BMPs and 

alternative practices. Owner implemented BMPs reflect those that would likely be implemented 

by land owners without incentives, while the typical incentive BMPs are those that that either 

reasonably funded cost share program or modest regulatory approach would obtain 

implementation. The alternative practices are those that are more expensive but would be 

needed if additional nutrient reductions are needed beyond what the first two levels could obtain. 

Table 9 provides the estimated existing total P load from the watershed compared to estimated 

BMP reductions in terms of percentages, loads, and costs for an anticipate BMP program that 

could be reasonably implemented over the next ten years. Tables 10 and 11 provide the same 

information as Tables 8 and 9 except for N instead of P. Table 10 provides a summary of the N 
4

unit loads and estimated BMP reduction factors for the three categories of owner implemented 

and typical incentive BMPs and alternative practices. Table 11 provides the estimated existing 

total N load from the watershed compared to estimated BMP reductions in terms of percentages 

and loads for an anticipate BMP program that could be reasonably implemented over the next ten 

years. The estimated annual average implementation costs are also provided in Tables 9 and 11, 

which have been adjusted to 2008 costs from the 2006 costs provided in Appendix A. 

Caloosahatchee River Watershed 

Figure 2 shows the basins within the Caloosahatchee watershed. The 2004 land use distribution 

for the C-43 basin was provided by SFWMD and is presented in Table 12. As can be seen, the 

table provides additional land use breakdowns beyond the twenty primary land use categories 

required for the project. These additional data were used during the development of the unit 

loads, but were integrated within the twenty categories for the final tables to prevent confusion. 

Measured data for the major structures on the C-43 canal were provided by the SFWMD and are 

presented in Table 13. Because of the influence of the Lake Okeechobee releases, only the basin 

(Freshwater West) between the S-78 and S-79 structures were considered reliable enough for 

comparisons to actual land source area discharges. Unmonitored flows released from the Lake 

Okeechobee, Nicodemus Slough, and the S-4 basin into the Freshwater East basin were 

considered more problematic than potential bypass water around S-78 as documented by the 

WAM model results (SWET, 2008). Therefore, the loads differences between these two 

structures shown in Table 13 were used for verification of the land use unit loads. The high 

measured discharge rates are a concern and are discussed further below. 

The initial estimates of the unit nutrient loads were developed from the Okeechobee Basin data 

provided in the BMP Letter Report (Bottcher, 2006), general Florida estimates by Harper and 

Baker (2003 and 2007), WMM EMC estimates developed by CDM (2007), and the WAM 

modeling results for the USACE (SWET, 2008). The final N and P unit loads for the C-43 basin 

presented in Table 14 were developed as an iterative process starting with the initial unit loads 

estimates linked to a basin spreadsheet where the accumulative N and P loads from each basin 

could be calculated by multiplying the land use acreage by the unit loads. The net N and P loads 

were then compared to the measured basin and basin loads to verify if the net loads were at least 

in the ballpark and how the calculated and measured N and P loads for each of the basins 

compared. It was clear that the dominant land uses in the western basins were improved pasture 

and citrus with limited urban around the Le Belle area. The more highly developed area is 

located in the western (tidal and north coastal) basins. Using just the Freshwater West basin, 

however, it was possible to estimate the relative importance of the various land uses and 

adjustments were made accordingly to obtain a reasonable agreement of runoff and nutrient 

loads and concentrations for each of the basins. However, it was observed that measured runoff 

for the Freshwater West basin seems high at 22 inches per year as seen in Table 16, which makes 

the units loads higher than expected. Therefore, the basin comparisons focused more on 

matching the concentrations because they would be less influenced by any flow errors that might 

be the result of unmeasured inter-basin transfers. Since the unit loads are a function of both 

concentration and flow, it was first necessary to establish reasonable runoff coefficients for the 

various land uses (Harper and Baker, 2007). The resulting annual average runoff for the various 

land uses are provided in Table 16. Table 16 also provides the resulting N and P unit loads and 
5

concentrations from the iterative process of adjusting individual land use unit loads which 

multiplied by the acreage of each land use within the basins (Table 15) to obtain reasonable basin 

runoff (Table 16), P loads (Table 17), and N loads (Table 18) comparison to observed data. The 

P unit load factors were adjusted by hand. The N unit loads were also initially adjusted by hand, 

but then a global multiplier factor was used to obtain reasonable matches to observed data at the 

basin level. The verification for the N and P loads and concentrations are also provided in 

Tables 17 and 18, respectively at the bottom of the tables. Note that the net calculated loads and 

concentrations are slightly higher than observed data because these represent net source loads 

which do not reflect the additional assimilation that is expected in the streams and canals before 

reaching the basin outlets. 

 

The next step was to establish BMP N and P reduction estimates for the C-43 basin. This was 

done by adding BMP reduction estimates for the six additional land use categories to the BMP 

reduction spreadsheets developed by Bottcher (2006). The resulting BMP reduction estimates 

and costs for N and P are presented in Appendix B. These tables reflect the updated unit loads 

provided in Table 14. Table 19 provides a summary of the P unit loads and estimated BMP 

reduction factors for the three categories of owner implemented and typical incentive BMPs and 

alternative practices. Owner implemented BMPs reflect those that would likely be implemented 

by land owners without incentives, while the typical incentive BMPs are those that that either 

reasonably funded cost share program or modest regulatory approach would obtain 

implementation. The alternative practices are those that are more expensive but would be 

needed if additional nutrient reductions are needed beyond what the first two levels could obtain. 

Table 20 provides the estimated existing total P load from the C-44 basin compared to estimated 

BMP reductions in terms of percentages, loads, and costs for an anticipated BMP program that 

could be reasonably implemented over the next ten years. Tables 21 and 22 provide the same 

information as Tables 19 and 20 except for N. Table 21 provides a summary of the N unit loads 

and estimated BMP reduction factors for the three categories of owner implemented and typical 

incentive BMPs and alternative practices. Table 22 provides the estimated existing total N load 

from the C-44 basin compared to estimated BMP reductions in terms of percentages, loads and 

costs for an anticipate BMP program that could be reasonably implemented over the next ten 

years. The estimated annual average implementation costs are also provided in Tables 20 and 22 

for P and N, respectively. The costs have been adjusted to 2008 costs from the 2006 costs 

provided in Appendix A. 
6

REFERENCES 

CDM. 2007. Nutrient Load Assessment Estero Bay and Caloosahatchee Watershed. Final 

Report to South Florida Water Management District. West Palm Beach, FL. 

Graves, G.A., Y. Wan, and D.L. Fike. 2004. Water Quality Characteristics of Storm Water 

From Major Land Uses in South Florida. J. American Water Resources Association. 

1405:1419 

Harper, H.H. and D.M. Baker. 2003. Evaluation of Alternative Stormwater Regulations for 

Southwest Florida. Final Report prepared by Environmental Research and Design for 

the Florida Department of Environmental Protection, Tallahassee, FL. 

Harper, H.H. and D.M. Baker. 2007. Evaluation of Current Stormwater Design Criteria within 

the State of Florida. Final Report prepared by Environmental Research and Design 

for the Florida Department of Environmental Protection, Tallahassee, FL. 

SWET. 2006. Phosphorus Reduction Performance and Implementation Costs under BMPs and 

Technologies in the Lake Okeechobee Protection Plan Area. Letter Report to Joyce 

Zhang, South Florida Water Management District. 

SWET. 2008. Assessment of the Caloosahatchee River (C-43) Basin Using the WAM Model. 

Final Report to the US Army Corps of Engineers. Jacksonville, FL. 
7

Figure 1. Basin Layout for the St. Lucie River Watershed
8

Figure 2. Basin Layout for the Caloosahatchee River Watershed 
9

Table 1. Land Use Distribution in the St. Lucie Watershed

Land Use Category Land Use Description FLUCCS Area (ac) Percent

Sum_Area 

(ac) Percent

Residential Low Density Residential Low Density 1100 22,050 4.29% 22,050 4.30%

Residential Medium Density Residential Medium Density 1200 38,206 7.43% 38,206 7.40%

Residential High Density Residential High Density 1300 7,698 1.50% 7,698 1.50%

Commercial and Services 1400 5,090 0.99%

Industrial 1500 2,034 0.40%

Extractive 1600 640 0.12%

Institutional 1700 2,977 0.58%

Recreational 1800 5,167 1.00%

Improved Pastures Improved Pastures 2110 106,321 20.67% 106,321 20.70%

Unimproved Pastures Unimproved Pastures 2120 15,033 2.92% 15,033 2.90%

Woodland Pastures 2130 25,205 4.90%

Rangeland 3000 14,147 2.75%

Row Crops Row Crops 2140 7,881 1.53% 7,881 1.50%

Sugar Cane Sugar Cane 2156 5,562 1.08% 5,562 1.10%

Citrus Citrus 2210 116,442 22.64% 116,442 22.60%

Sod Farms Sod Farms 2420 294 0.06% 294 0.10%

Ornamentals Ornamentals 2430 1,246 0.24% 1,246 0.20%

Horse Farms Horse Farms 2510 784 0.15% 784 0.20%

Dairies Dairies 2520 419 0.08% 419 0.10%

Field Crops 2150 2,800 0.54%

Other Groves 2230 48 0.01%

Cattle Feeding Operations 2310 105 0.02%

Poultry Feeding Operations 2320 107 0.02%

Tree Nurseries 2410 463 0.09%

Specialty Farms 2500 133 0.03%

Aquaculture 2540 204 0.04%

Fallow Crop Land 2610 248 0.05%

Tree Plantations Tree Plantations 4400 0 0.00% 0 0.00%

Water Water 5000 11,411 2.22% 11,411 2.20%

Upland Forests 4000 37,608 7.31%

Wetlands 6000 61,052 11.87%

Barren Land 7000 2,613 0.51%

Open Land 1900 4,108 0.80%

Transportation Transportation 8100 5,665 1.10% 5,665 1.10%

Communication 8200 91 0.02%

Utilities 8300 10,438 2.03%

Total 514,287 100.00% 514,287 100.00%

Communication/Utilities 10,529 2.00%

Other Areas

4,108 0.80%

Natural Areas

105,380 20.50%

Other Urban

15,907 3.10%

Woodland Pastures/Rangeland 39,351 7.70%
10

Table 2 Summary of Measured Nitrogen and Phosphorus Load to SLE

Calculated 

Runoff (in)

Basins 4 5 6 15055 23620 18.8 34 1182 6 218.96

C-23 112675 152789 16.3 330 1750 91 480.55

C-24 87706 178853 24.5 355 1609 76 343.25

C-44&S-153 129719 158194 14.6 300 1540 40 203.38

North Fork* 119168 126152 12.7 185 1191 43 278

Tidal St. Lucie** 49965 59408 14.3 91 1244 21 285.16

Lake Okeechobee - 414754 922 1802 96 188.14

Total 514287 1113771 2218 1615 373 271.33

for TN concentration for North Fork basin, South Fork basin, and Basin 4 5 6.

basin, and Lake Okeechobee. WaSh Model output data are used for flow from

North Fork basin, South Fork basin, and Basin 4 5 6.

(2) Measured data are used for TN concentration for C-23 basin, C-24 basin, 

C-44&S-153 basin, and Lake Okeechobee. WaSh Model output data are used

(1) Measured data are used for flow from C-23 basin, C-24 basin, C-44&S-153

Sub-watershed

Area 

(acres)

Average 

Annual 

Discharge(1) 

(1995-2005) 

(Acre-ft)

Average 

Annual 

TN Load(2) 

(1995-2005) 

(MTons)

Average 

Annual 

TP Conc. 

(Calculat

ed) (1995-

2005) 

(ppb)

Average 

Annual 

TP Load(2) 

(1995-

2005) 

(MTons)

Average 

Annual 

TN Conc. 

(Calculated

) (1995-

2005) (ppb)

*North Fork basin includes North Fork and N. Mid. Estuary 

**Tidal St. Lucie basin includes South Fork and S. Mid. Estuary
11

Table 3. Estimated Runoff, Unit N and P Loads and Concentration for 2004 Land Uses in the St. Lucie Watershed

Land Use Category Land Use Description FLUCCS Runoff

Unit N 

Load N Conc. Unit P Load P Conc.

(in/yr) ) (mg/l) (lbs/acre/yr) (mg/l)

Residential Low Density Residential Low Density1 1100 17.57 4.95 1.25 0.49 0.12

Residential Medium Density Residential Medium Density2 1200 20.76 7.20 1.53 1.40 0.30

Residential High Density Residential High Density2 1300 23.96 10.80 1.99 3.00 0.55

Commercial and Services2 1400 25.55 9.90 1.71 1.40 0.24

Industrial2 1500 27.15 9.00 1.47 2.40 0.39

Extractive2 1600 23.96 6.30 1.16 0.66 0.12

Institutional2 1700 23.96 6.30 1.16 2.40 0.44

Recreational2 1800 17.57 6.30 1.59 0.96 0.24

Improved Pastures Improved Pastures 2110 19.16 9.99 2.30 1.90 0.44

Unimproved Pastures Unimproved Pastures 2120 15.97 4.95 1.37 0.92 0.25

Woodland Pastures 2130 15.97 3.69 1.02 0.88 0.24

Rangeland 3000 15.97 3.69 1.02 0.28 0.08

Row Crops Row Crops 2140 22.36 13.50 2.67 4.50 0.89

Sugar Cane Sugar Cane 2156 19.16 7.20 1.66 0.63 0.15

Citrus Citrus 2210 19.16 7.65 1.76 1.80 0.42

Sod Farms Sod Farms 2420 19.16 8.10 1.87 2.52 0.58

Ornamentals Ornamentals 2430 19.16 10.80 2.49 2.90 0.67

Horse Farms Horse Farms 2510 15.97 14.40 3.99 1.82 0.50

Dairies Dairies 2520 15.97 18.00 4.98 9.38 2.60

Field Crops 2150 15.97 5.96 1.65 2.96 0.82

Mixed Crops 2160 19.16 9.90 2.28 3.50 0.81

Fruit Orchards 2220 19.16 8.10 1.87 2.30 0.53

Other Groves 2230 19.16 8.10 1.87 2.30 0.53

Cattle Feeding Operations 2310 19.16 48.65 11.22 8.96 2.07

Poultry Feeding Operations 2320 19.16 9.00 2.08 1.50 0.35

Tree Nurseries 2410 15.97 10.80 2.99 2.90 0.80

Specialty Farms 2500 15.97 7.20 1.99 1.82 0.50

Aquaculture 2540 7.99 9.00 4.98 0.70 0.39

Fallow Crop Land 2610 19.16 6.30 1.45 0.70 0.16

Tree Plantations Tree Plantations 4400 15.97 2.79 0.77 0.18 0.05

Water Water 5000 3.19 0.81 1.12 0.05 0.07

Upland Forests (not including 

4400's)

4000 14.37 2.25 0.69 0.28 0.09

Wetlands 6000 1.60 1.35 3.74 0.01 0.03

Barren Land 7000 23.96 6.30 1.16 0.75 0.14

Open Land 1900 15.97 3.60 1.00 0.28 0.08

Transportation Transportation 8100 27.15 8.28 1.35 1.65 0.27

Communications 8200 15.97 5.40 1.49 0.48 0.13

Utilities 8300 15.97 5.40 1.49 0.48 0.13

1 Assumed on Septic

2 Assumed Discharge from WWT outside basin

Communication/Utilities

Other Urban

Woodland Pastures/Rangeland

Other Areas

Natural Areas
12

Table 4. Acreage of Land Uses within the St. Lucie Watershed

FLUCCS Basins 4 5 6 C-23 C-24 C-44&S-153 North Fork* Tidal St. Lucie** Grand Total

1100 4315.6 1909.4 1236.1 1813.7 9445 3329.8 22049.7

1200 1236.1 303.7 2505.9 314.9 30453.4 3392.3 38206.3

1300 702.6 295 185.7 4784.2 1730.3 7697.8

1400 222.9 9 39.8 204.4 3453.9 1159.8 5089.8

1500 133.2 48.3 55.5 76.7 1552.3 167.8 2033.7

1600 0.8 411.5 92.3 135.2 639.8

1700 110.3 661.7 21.7 97.7 1567.1 518.3 2976.7

1800 683.8 254.8 665.6 209.5 2308.4 1045.2 5167.3

1900 110.8 9.8 74.7 148.7 3291.5 472.2 4107.5

2110 1006.7 33628 33949.7 23185 4998.8 9552.4 106320.6

2120 86.4 5062 6064.3 2167.9 558.4 1094.1 15033.1

2130 374.6 8697.3 6890.3 6457.9 1071.8 1712.9 25204.8

2140 156.1 1696.2 1550.3 852.5 1166.2 2459.9 7881.1

2150 1574.6 834.7 390.9 2800.2

2156 5240.1 321.7 5561.8

2210 30.2 32466.1 17487.8 42754.5 20678.2 3025.4 116442.2

2220 0

2230 5 17.1 26.2 48.3

2310 104.7 104.7

2320 44.3 62.5 106.8

2410 100.2 153.8 55.5 85.3 68.3 0.1 463.1

2420 294.1 294.1

2430 211 25.1 267.6 237.9 504.4 1246

2500 28.7 23.9 79.9 132.6

2510 53.7 54 14.1 591.6 71.1 784.4

2520 419.1 419.1

2540 60.1 70.4 23.3 9.5 40.8 204.2

2610 216.7 31.3 247.9

3000 394.5 1603.5 220.1 6383.5 3494 2051 14146.6

4000 2679 2723.8 1264.5 11535.9 12030.8 7373.6 37607.6

5000 382.5 1810.5 1218.4 1890.7 4317.3 1791.3 11410.7

6000 1262.5 16278.9 12248.2 15114.6 9485.1 6662.2 61051.5

7000 1108.1 297.8 939 235.2 33.2 2613.4

8100 297.6 455.4 521.1 611.2 2623.4 1156.6 5665.3

8200 10.9 10.2 5.6 64.3 91

8300 428.3 916.1 102.4 7808.5 1099.2 83.1 10437.6

Grand Total 15055.4 112674.5 87705.8 129718.9 119167.9 49964.7 514287.2

*North Fork basin includes North Fork and N.Mid.Estuary 

**Tidal St. Lucie basin includes South Fork and S.Mid.Estuary
13

Table 5. Runoff in Acre-ft/yr to Stream by Land Use

FLUCCS Basins 4 5 6 C-23 C-24 C-44&S-153 North Fork* Tidal St. Lucie** Grand Total

1100 6318 2795 1810 2655 13827 4875 32280

1200 2139 525 4336 545 52689 5869 66102

1300 1403 0 589 371 9551 3454 15367

1400 475 19 85 435 7355 2470 10838

1500 301 109 126 174 3512 380 4601

1600 2 821 0 0 184 270 1277

1700 220 1321 43 195 3128 1035 5942

1800 1001 373 974 307 3379 1530 7565

1900 147 13 99 198 4381 628 5467

2110 1608 53706 54219 37028 7983 15256 169799

2120 115 6737 8071 2885 743 1456 20007

2130 499 11575 9170 8595 1426 2280 33544

2140 291 3160 2889 1588 2173 4583 14684

2150 0 2096 1111 520 0 0 3727

2156 0 0 0 8369 0 514 8882

2210 48 51850 27929 68281 33024 4832 185964

2220 0 0 0 0 0 0 0

2230 8 27 0 0 42 0 77

2310 0 167 0 0 0 0 167

2320 0 0 71 100 0 0 171

2410 133 205 74 114 91 0 616

2420 0 0 0 470 0 0 470

2430 337 0 40 427 380 806 1990

2500 0 0 0 38 32 106 176

2510 71 72 19 787 0 95 1044

2520 0 558 0 0 0 0 558

2540 40 47 16 0 6 27 136

2610 0 346 0 0 50 0 396

3000 525 2134 293 8496 4650 2730 18827

4000 3209 3263 1515 13818 14410 8832 45046

5000 102 482 324 503 1149 477 3037

6000 168 2167 1630 2012 1262 887 8125

7000 0 2212 595 1875 470 66 5217

8100 673 1030 1179 1383 5935 2617 12818

8200 15 14 0 7 86 0 121

8300 570 1219 136 10392 1463 111 13891

Grand Total 20417 149043 117341 172566 173382 66183 698,932

(in/yr) 16 16 16 16 17 16 16

*North Fork basin includes North Fork and N.Mid.Estuary 

**Tidal St. Lucie basin includes South Fork and S.Mid.Estuary
14

Table 6. Net P Loads in Pounds/year to Stream within the St. Lucie watershed by Land Use

FLUCCS Basins 4 5 6 C-23 C-24 C-44&S-153 North Fork* Tidal St. Lucie** Grand Total

1100 2115 936 606 889 4628 1632 10804

1200 1731 425 3508 441 42635 4749 53489

1300 2108 0 885 557 14353 5191 23093

1400 312 13 56 286 4835 1624 7126

1500 320 116 133 184 3726 403 4881

1600 1 272 0 0 61 89 422

1700 265 1588 52 234 3761 1244 7144

1800 656 245 639 201 2216 1003 4961

1900 31 3 21 42 922 132 1150

2110 1913 63893 64504 44052 9498 18150 202009

2120 79 4657 5579 1994 514 1007 13830

2130 330 7654 6063 5683 943 1507 22180

2140 702 7633 6976 3836 5248 11070 35465

2150 0 4668 2475 1159 0 0 8301

2156 0 0 0 3301 0 203 3504

2210 54 58439 31478 76958 37221 5446 209596

2220 0 0 0 0 0 0 0

2230 12 39 0 0 60 0 111

2310 0 938 0 0 0 0 938

2320 0 0 66 94 0 0 160

2410 291 446 161 247 198 0 1343

2420 0 0 0 741 0 0 741

2430 612 0 73 776 690 1463 3613

2500 0 0 0 52 43 145 241

2510 98 98 26 1077 0 129 1428

2520 0 3931 0 0 0 0 3931

2540 42 49 16 0 7 29 143

2610 0 152 0 0 22 0 174

3000 110 449 62 1787 978 574 3961

4000 750 763 354 3230 3369 2065 10530

5000 19 91 61 95 216 90 571

6000 13 163 122 151 95 67 611

7000 0 831 223 704 176 25 1960

8100 491 751 860 1008 4329 1908 9348

8200 5 5 0 3 31 0 44

8300 206 440 49 3748 528 40 5010

Grand Total 13264 159686 125049 153531 141301 59983 652814

Conc.(ppbl) 233 384 382 319 292 325 335

Meas.Conc.(ppb) 219 481 343 203 278 285

Lake Okee (lbs) 211200

Calc. (Mt/yr) 6 73 57 70 64 27 393

Measured (Mt/yr) 6 91 76 40 43 21 373

*North Fork basin includes North Fork and N.Mid.Estuary 

**Tidal St. Lucie basin includes South Fork and S.Mid.Estuary
15

Table 7. Net N Loads in Pounds/year to Stream within the St. Lucie Watershed by Land Use

FLUCCS Basins 4 5 6 C-23 C-24 C-44&S-153 North Fork* Tidal St. Lucie** Grand Total

1100 21362 9452 6119 8978 46753 16483 109146

1200 8900 2187 18042 2267 219264 24425 275085

1300 7588 0 3186 2006 51669 18687 83136

1400 2207 89 394 2024 34194 11482 50389

1500 1199 435 500 690 13971 1510 18303

1600 5 2592 0 0 581 852 4031

1700 695 4169 137 616 9873 3265 18753

1800 4308 1605 4193 1320 14543 6585 32554

1900 399 35 269 535 11849 1700 14787

2110 10057 335944 339158 231618 49938 95428 1062143

2120 428 25057 30018 10731 2764 5416 74414

2130 1382 32093 25425 23830 3955 6321 93006

2140 2107 22899 20929 11509 15744 33209 106395

2150 0 9384 4975 2330 0 0 16689

2156 0 0 0 37729 0 2316 40045

2210 231 248366 133782 327072 158188 23144 890783

2220 0 0 0 0 0 0 0

2230 41 139 0 0 212 0 391

2310 0 5094 0 0 0 0 5094

2320 0 0 399 563 0 0 961

2410 1082 1661 599 921 738 1 5001

2420 0 0 0 2382 0 0 2382

2430 2279 0 271 2890 2569 5448 13457

2500 0 0 0 207 172 575 955

2510 773 778 203 8519 0 1024 11295

2520 0 7544 0 0 0 0 7544

2540 541 634 210 0 86 367 1838

2610 0 1365 0 0 197 0 1562

3000 1456 5917 812 23555 12893 7568 52201

4000 6028 6129 2845 25956 27069 16591 84617

5000 310 1467 987 1531 3497 1451 9243

6000 1704 21977 16535 20405 12805 8994 82420

7000 0 6981 1876 5916 1482 209 16464

8100 2464 3771 4315 5061 21722 9577 46909

8200 59 55 0 30 347 0 491

8300 2313 4947 553 42166 5936 449 56363

Grand Total 79917 762762 616731 803355 723011 303076 3288847

Conc.(ppb) 1404 1836 1885 1670 1496 1643 1688

Meas.Conc.(ppb) 1182 1750 1609 1540 1191 1244

Lake Okee (lbs) 2028400

Calc. (Mt/yr) 36 347 280 365 329 138 2417

Measured (Mt/yr) 34 330 355 300 185 91 2217

*North Fork basin includes North Fork and N.Mid.Estuary 

**Tidal St. Lucie basin includes South Fork and S.Mid.Estuary
16

Table 8. Land Use Categories, Unit Load Factors, and P Reduction Factors for the St. Lucie Watershed

Land Use Category Land Use Description FLUCCS Unit P Load 

(lbs/acre/yr)

Owner 

Implemented 

BMPs (1)

Typical Cost 

Share BMPs

Alternative 

Practices

Residential Low Density Residential Low Density1 1100 0.49 5% 0% 0%

Residential Medium Density Residential Medium Density2 1200 1.40 5% 0% 0%

Residential High Density Residential High Density2 1300 3.00 5% 5% 0%

Other Urban Commercial/Industrial2 1400-1800 1.54 5% 5% 0%

Improved Pastures Improved Pastures 2110 1.90 11% 19% 49%

Unimproved Pastures Unimproved Pastures 2120 0.92 7% 13% 44%

Woodland Pastures/Rangeland Woodland/Range Pastures 2130/3000 0.66 4% 6% 35%

Row Crops Row Crops 2140 4.50 30% 30% 50%

Sugar Cane Sugar Cane 2156 0.63 10% 23% 52%

Citrus Citrus 2210 1.80 12% 20% 42%

Sod Farms Sod Farms 2420 2.52 20% 27% 50%

Ornamentals Ornamentals 2430 2.90 32% 35% 50%

Horse Farms Horse Farms 2510 1.82 20% 22% 49%

Dairies Dairies 2520 9.38 9% 28% 48%

Other Areas Other Areas 2150-2610 2.78 15% 25% 36%

Tree Plantations Tree Plantations 4400 0.18 1% 10% 50%

Water Water 5000 0.05 0% 0% 0%

Natural Areas Forrests/wetlands/Open 4000/6000 0.14 0% 0% 0%

Transportation Transportation 8100 1.65 10% 23% 52%

Communication/Utilities Communication/Utilities 8200/8300 0.48 5% 5% 0%

1 Assumed on Septic

2 Assumed all of Discharge from WWT outside basin

Estimated Phosphorus Reduction
17

Table 9. Land Use Categories, Unit Load Factors, and Estimated P Reduction Factors Using 2004 Land Use

 for the St. Lucie Watershed

Land Use Category Land Use Description FLUCCS Percent 

of Basin

Unit P Load Total P Annual Cost 

(lbs/acre/yr) (MT/yr) (percent) (MT/yr) ($)

Residential Low Density Residential Low Density1 1100 4.29% 0.49 4.9 5% 0.2 25,288,704

Residential Medium Density Residential Medium Density2 1200 7.43% 1.40 24.3 5% 1.2 43,817,697

Residential High Density Residential High Density2 1300 1.50% 3.00 10.5 10% 1.0 17,657,364

Other Urban Commercial/Industrial2 1400-1800 3.09% 1.54 11.2 10% 1.1 32,580,227

Improved Pastures Improved Pastures 2110 20.67% 1.90 91.8 30% 27.5 1,886,220

Unimproved Pastures Unimproved Pastures 2120 2.92% 0.92 6.3 20% 1.3 71,119

Woodland Pastures/Rangeland Woodland/Range Pastures 2130/3000 7.65% 0.66 11.9 10% 1.2 166,222

Row Crops Row Crops 2140 1.53% 4.50 16.1 60% 9.7 621,401

Sugar Cane Sugar Cane 2156 1.08% 0.63 1.6 33% 0.5 219,276

Citrus Citrus 2210 22.64% 1.80 95.3 32% 30.5 9,781,128

Sod Farms Sod Farms 2420 0.06% 2.52 0.3 47% 0.2 11,591

Ornamentals Ornamentals 2430 0.24% 2.90 1.6 67% 1.1 98,245

Horse Farms Horse Farms 2510 0.15% 1.82 0.6 42% 0.3 12,982

Dairies Dairies 2520 0.08% 9.38 1.8 37% 0.7 490,398

Other Areas Other Areas 2150-2610 0.80% 2.78 5.2 40% 2.1 65,079

Tree Plantations Tree Plantations 4400 0.00% 0.18 0.0 11% 0.0 0

Water Water 5000 2.22% 0.05 0.3 0% 0.0 0

Natural Areas Forrests/wetlands/Open 4000/6000 20.49% 0.14 6.5 0% 0.0 0

Transportation Transportation 8100 1.10% 1.65 4.2 33% 1.4 223,337

Communication/Utilities Communication/Utilities 8200/8300 2.05% 0.48 2.3 10% 0.2 6,711,109

Total Basin 100.00% 1.22 286 28% 79 122,044,735

1 Assumed on Septic

2 Assumed all of Discharge from WWT outside basin

Estimated P 

Reduction
18

Table 10. Land Use Categories, Unit Load Factors, and N Reduction Factors for the St. Lucie Watershed

Land Use Category Land Use Description FLUCCS Unit N Load 

(lbs/acre/yr)

Owner 

Implemented 

BMPs

Typical 

Incentive 

BMPs

Alternative 

Practices

Residential Low Density Residential Low Density1 1100 4.95 15% 15% 15%

Residential Medium Density Residential Medium Density2 1200 7.20 25% 25% 15%

Residential High Density Residential High Density2 1300 10.80 30% 25% 15%

Other Urban Commercial/Industrial2 1400-1800 7.80 25% 25% 15%

Improved Pastures Improved Pastures 2110 9.99 17% 10% 30%

Unimproved Pastures Unimproved Pastures 2120 4.95 11% 8% 30%

Woodland Pastures/Rangeland Woodland/Range Pastures 2130/3000 3.69 4% 6% 20%

Row Crops Row Crops 2140 13.50 30% 30% 50%

Sugar Cane Sugar Cane 2156 7.20 10% 23% 52%

Citrus Citrus 2210 7.65 10% 20% 42%

Sod Farms Sod Farms 2420 8.10 20% 27% 50%

Ornamentals Ornamentals 2430 10.80 25% 25% 25%

Horse Farms Horse Farms 2510 14.40 30% 22% 30%

Dairies Dairies 2520 18.00 20% 40% 48%

Other Areas Other Areas 2150-2610 7.91 15% 25% 36%

Tree Plantations Tree Plantations 4400 2.79 5% 10% 25%

Water Water 5000 0.81 0% 0% 0%

Natural Areas Forrests/wetlands/Open 4000/6000 1.88 0% 0% 0%

Transportation Transportation 8100 8.28 20% 23% 25%

Communication/Utilities Communication/Utilities 8200/8300 5.40 30% 25% 15%

1 Assumed on Septic

2 Assumed all of Discharge from WWT outside basin

Estimated Nitrogen Reduction
19

Table 11. Land Use Categories, Unit Load Factors, and Estimated N Reduction Factors Using 2004 Land Use

 for the St. Lucie Watershed

Land Use Category Land Use Description FLUCCS Percent 

of Basin

Unit N Load Total N Annual Cost 

(lbs/acre/yr) (MT/yr) (percent) (MT/yr) ($)

Residential Low Density Residential Low Density1 1100 4.29% 4.95 49.6 30% 14.9 34,543,867

Residential Medium Density Residential Medium Density2 1200 7.43% 7.20 125.0 50% 62.5 59,891,448

Residential High Density Residential High Density2 1300 1.50% 10.80 37.8 55% 20.8 12,067,329

Other Urban Commercial/Industrial2 1400-1800 3.09% 7.80 56.4 55% 31.0 26,857,201

Improved Pastures Improved Pastures 2110 20.67% 9.99 482.8 27% 130.4 1,286,059

Unimproved Pastures Unimproved Pastures 2120 2.92% 4.95 33.8 19% 6.4 43,872

Woodland Pastures/Rangeland Woodland/Range Pastures 2130/3000 7.65% 3.69 66.0 10% 6.6 126,934

Row Crops Row Crops 2140 1.53% 13.50 48.4 60% 29.0 423,683

Sugar Cane Sugar Cane 2156 1.08% 7.20 18.2 33% 6.0 150,594

Citrus Citrus 2210 22.64% 7.65 404.9 30% 121.5 13,942,553

Sod Farms Sod Farms 2420 0.06% 8.10 1.1 47% 0.5 7,903

Ornamentals Ornamentals 2430 0.24% 10.80 6.1 50% 3.1 49,989

Horse Farms Horse Farms 2510 0.15% 14.40 5.1 52% 2.7 9,483

Dairies Dairies 2520 0.08% 18.00 3.4 60% 2.1 298,538

Other Areas Other Areas 2150-2610 0.80% 7.91 14.8 40% 5.9 57,682

Tree Plantations Tree Plantations 4400 0.00% 2.79 0.0 15% 0.0 0

Water Water 5000 2.22% 0.81 4.2 0% 0.0 0

Natural Areas Forrests/wetlands/Open 4000/6000 20.49% 1.88 90.1 0% 0.0 0

Transportation Transportation 8100 1.10% 8.28 21.3 43% 9.2 201,666

Communication/Utilities Communication/Utilities 8200/8300 2.05% 5.40 25.8 55% 14.2 12,310,996

Total Basin 100% 6.23 1,457 31% 446 150,202,466

1 Assumed on Septic

2 Assumed all of Discharge from WWT outside basin

Estimated N 

Reduction
20

Table 12. Land Use Distribution for the Caloosahatchee Watershed

Land Use Category Land Use Description FLUCCS Area (ac) Percent Area (ac) Percent

Residential Low Density Residential Low Density 1100 76,863 7.12% 76,863 7.10%

Residential Medium Density Residential Medium Density 1200 33,396 3.09% 33,396 3.10%

Residential High Density Residential High Density 1300 11,453 1.06% 11,453 1.10%

Commercial and Services 1400 8,906 0.82%

Industrial 1500 2,648 0.25%

Extractive 1600 2,278 0.21%

Institutional 1700 3,675 0.34%

Recreational 1800 6,062 0.56%

Improved Pastures Improved Pastures 2110 117,152 10.85% 117,152 10.80%

Unimproved Pastures Unimproved Pastures 2120 23,827 2.21% 23,827 2.20%

Woodland Pastures 2130 20,280 1.88%

Rangeland 3000 57,850 5.36%

Row Crops Row Crops 2140 9,656 0.89% 9,656 0.90%

Sugar Cane Sugar Cane 2156 87,741 8.13% 87,741 8.10%

Citrus Citrus 2210 96,684 8.95% 96,684 9.00%

Sod Farms Sod Farms 2420 5,070 0.47% 5,070 0.50%

Ornamentals Ornamentals 2430 861 0.08% 861 0.10%

Horse Farms Horse Farms 2510 202 0.02% 202 0.00%

Dairies Dairies 2520 56 0.01% 56 0.00%

Field Crops 2150 5,326 0.49%

Mixed Crops 2160 17 0.00%

Fruit Orchards 2220 12 0.00%

Other Groves 2230 1,995 0.18%

Tree Nurseries 2410 971 0.09%

Specialty Farms 2500 165 0.02%

Aquaculture 2540 215 0.02%

Fallow Crop Land 2610 2,209 0.20%

Tree Plantations Tree Plantations 4400 42,498 3.94% 42,498 3.90%

Water Water 5000 130,368 12.07% 130,368 12.10%

Upland Forests (not including 

4400's) 4000 84,379

7.81%

Wetlands 6000 184,666 17.10%

Barren Land 7000 5,866 0.54%

Open Land 1900 49,378 4.57%

Transportation Transportation 8100 4,915 0.46% 4,915 0.50%

Communications 8200 96 0.01%

Utilities 8300 2,063 0.19%

Total 1,079,796 100.00% 1,079,796 100.00%

Communication/Utilities 2,159 0.20%

Other Areas 10,909 1.00%

Natural Areas 324,289 30.00%

Other Urban 23,568 2.20%

Woodland Pastures/Rangeland 78,130 7.20%
21

Table 13. Summary of Annual Flow and Loads for TP and TN along the main stem of the Caloosahatchee River 

Flow TP Load TP Conc. TN Load TN Conc. Flow TP Load TP Conc. TN Load TN Conc. Flow TP Load TP Conc. TN Load TN Conc. Flow T

acre-feet mtons ug/L mtons mg/L acre-feet mtons ug/L mtons mg/L acre-feet mtons ug/L mtons mg/L acre-feet m

1990 120,575 14.0 94 237.6 1.60 174,966 33.0 153 322.4 1.49 423,951 101.0 193 936.9 1.79 248,986 

 

1991 63,594 7.3 93 136.2 1.74 288,783 72.1 202 670.0 1.88 922,265 193.2 170 1,890.5 1.66 633,481 

 

1992 193,275 22.9 96 344.7 1.45 437,933 93.2 172 756.4 1.40 943,491 406.5 349 2,198.8 1.89 505,559 

 

1993 500,243 30.7 50 1,382.3 2.24 645,118 68.2 86 972.4 1.22 1,230,588 182.0 120 2,334.1 1.54 585,470 

 

1994 770,253 50.7 53 1,345.0 1.42 1,044,125 119.2 93 2,201.9 1.71 1,633,414 216.6 108 3,380.2 1.68 589,289 

 

1995 2,110,116 113.5 44 4,311.3 1.66 2,381,744 186.4 63 3,244.1 1.10 3,379,883 314.1 75 5,482.4 1.32 998,139 

 

1996 474,489 47.0 80 797.6 1.36 568,330 58.2 83 853.6 1.22 941,009 129.5 112 1,647.2 1.42 372,680 

 

1997 158,049 16.2 83 393.5 2.02 290,448 36.2 101 661.3 1.85 756,311 114.8 123 1,413.3 1.51 465,864 

 

1998 1,618,473 135.5 68 2,988.8 1.50 1,831,790 204.9 91 3,216.9 1.42 2,613,724 296.8 92 4,309.0 1.34 781,933 

 

1999 564,104 52.4 75 945.3 1.36 848,093 123.6 118 1,602.2 1.53 1,578,821 324.1 166 3,041.8 1.56 730,729 

 

2000 477,520 104.7 178 1,683.5 2.86 409,244 47.1 93 687.8 1.36 619,878 118.6 155 1,061.9 1.39 210,634 

 

2001 72,771 9.0 101 172.2 1.92 176,661 66.0 303 462.5 2.12 835,815 232.8 226 1,694.6 1.64 659,154 

 

2002 466,052 57.4 100 969.6 1.69 888,496 154.4 141 1,774.4 1.62 1,491,120 318.2 173 3,166.7 1.72 602,624 

 

2003 1,396,713 101.5 59 2,454.0 1.42 1,745,887 209.3 97 3,239.4 1.50 2,589,761 335.0 105 4,529.1 1.42 843,874 

 

2004 1,120,739 127.3 92 2,146.6 1.55 1,247,980 128.0 83 1,996.4 1.30 1,853,038 230.2 101 2,815.2 1.23 605,058 

 

2005 2,266,435 384.6 138 4,597.7 1.64 2,898,397 476.4 133 5,821.6 1.63 3,734,684 577.7 125 6,740.1 1.46 836,287 

 

2006 353,758 65.1 149 732.9 1.68 463,033 88.2 154 856.5 1.50 920,989 193.0 170 1,689.2 1.49 457,956 

 

1990-2006 748,656 78.8 85 1,508.2 1.63 961,237 127.3 107 1,725.9 1.46 1,556,985 252.0 131 2,843.0 1.48 595,748 1995-2005 975,042 104.5 87 1,950.9 1.62 1,207,915 153.7 103 2,141.8 1.44 1,854,004 272.0 119 3,263.7 1.43 646,089 

Calendar 

Year

S-77 (02292000) S-78 (02292480) S-79 (02292900) Bas
22

Table 14. Estimated Runoff, Unit N and P Loads and Concentration for 2004 Land Uses in the Caloosahatchee Watershed

Land Use Category Land Use Description FLUCCS Runoff Unit N Load N Conc. Unit P Load P Conc.

(in/yr) (lbs/acre/yr) (mg/l) (lbs/acre/yr) (mg/l)

Residential Low Density Residential Low Density1 1100 27.4313 7.26 1.17 0.68 0.11

Residential Medium Density Residential Medium Density2 1200 32.4188 10.56 1.44 1.93 0.26

Residential High Density Residential High Density2 1300 39.9 15.84 1.75 4.14 0.46

Commercial and Services2 1400 39.9 14.52 1.61 1.93 0.21

Industrial2 1500 42.3938 13.20 1.38 3.31 0.35

Extractive2 1600 37.4063 9.24 1.09 0.91 0.11

Institutional2 1700 37.4063 9.24 1.09 3.31 0.39

Recreational2 1800 27.4313 9.24 1.49 1.32 0.21

Improved Pastures Improved Pastures 2110 29.925 14.65 2.16 1.93 0.29

Unimproved Pastures Unimproved Pastures 2120 24.9375 7.26 1.29 0.99 0.18

Woodland Pastures 2130 24.9375 5.41 0.96 0.83 0.15

Rangeland 3000 19.95 5.41 1.20 0.25 0.06

Row Crops Row Crops 2140 34.9125 19.80 2.51 3.45 0.44

Sugar Cane Sugar Cane 2156 29.925 10.56 1.56 0.55 0.08

Citrus Citrus 2210 29.925 11.22 1.66 0.90 0.13

Sod Farms Sod Farms 2420 29.925 11.88 1.75 2.79 0.41

Ornamentals Ornamentals 2430 29.925 15.84 2.34 4.00 0.59

Horse Farms Horse Farms 2510 24.9375 21.12 3.74 2.51 0.45

Dairies Dairies 2520 24.9375 26.40 4.68 12.94 2.29

Field Crops 2150 24.9375 8.74 1.55 4.09 0.73

Mixed Crops 2160 29.925 14.52 2.14 4.83 0.71

Fruit Orchards 2220 29.925 11.88 1.75 3.17 0.47

Other Groves 2230 29.925 11.88 1.75 3.17 0.47

Cattle Feeding Operations 2310 29.925 71.35 10.54 12.37 1.83

Poultry Feeding Operations 2320 29.925 13.20 1.95 2.07 0.31

Tree Nurseries 2410 24.9375 15.84 2.81 4.00 0.71

Specialty Farms 2500 24.9375 10.56 1.87 2.51 0.45

Aquaculture 2540 12.4688 13.20 4.68 0.97 0.34

Fallow Crop Land 2610 29.925 9.24 1.36 0.97 0.14

Tree Plantations Tree Plantations 4400 14.9625 4.09 1.21 0.21 0.06

Water Water 5000 4.9875 1.19 1.05 0.07 0.06

Upland Forests (not including 

4400's) 4000 14.9625 3.30 0.97 0.10 0.03

Wetlands 6000 7.48125 1.98 1.17 0.01 0.01

Barren Land 7000 37.4063 9.24 1.09 1.04 0.12

Open Land 1900 24.9375 5.28 0.94 0.39 0.07

Transportation Transportation 8100 49.875 12.14 1.08 2.28 0.20

Communications 8200 27.4313 7.92 1.28 0.66 0.11

Utilities 8300 24.9375 7.92 1.40 0.66 0.12

1 Assumed on Septic

2 Assumed about 70% of Discharge from WWT outside basin

Communication/Utilities

Other Urban

Woodland Pastures/Rangeland

Other Areas

Natural Areas
23

Table 15. Acreage of Land Uses within the Caloosahatchee Watershed

FLUCCS

Caloosahatc

hee Estuary

Freshwater 

East

Freshwater 

West Nearshore

North 

Coastal S-4 Tidal Grand Total

1100 19 3,015 14,869 4236 24,084 548 30,092 76,863

1200 65 383 1,758 1741 1,825 1,506 26,118 33,396

1300 15 59 398 983 1,434 77 8,486 11,453

1400 8 191 688 421 384 428 6,787 8,906

1500 236 445 6 23 1,264 673 2,648

1600 553 22 3 340 68 1,292 2,278

1700 0 105 245 91 475 213 2,545 3,675

1800 11 76 472 1193 1,039 257 3,014 6,062

1900 1 2,437 25,047 522 6,947 204 14,220 49,378

2110 1 36,795 55,555 231 2,381 797 21,392 117,152

2120 5,752 12,736 30 436 4,873 23,827

2130 3 5,924 10,033 67 83 4,171 20,280

2140 1,080 6,354 363 228 1,632 9,656

2150 422 1,269 8 56 38 3,533 5,326

2156 52,751 2,058 32,932 87,741

2160 17 17

2210 26,593 69,008 193 66 824 96,684

2220 12 12

2230 53 1793 6 143 1,995

2410 174 111 185 270 230 971

2420 289 2,947 1,833 5,070

2430 16 369 160 15 300 861

2500 79 17 68 165

2510 140 38 24 202

2520 18 38 56

2540 27 91 97 215

2610 133 1,124 80 68 803 2,209

3000 50 4,966 21,510 3087 8,929 278 19,030 57,850

4000 51 7,791 23,793 3396 10,881 359 38,108 84,379

4400 12,923 28,403 69 1,103 42,498

5000 15780 2,061 3,639 94206 6,848 717 7,117 130,368

6000 275 30,329 63,513 24493 21,682 1,193 43,181 184,666

7000 1,910 2,244 67 456 675 514 5,866

8100 6 741 645 36 488 330 2,668 4,915

8200 20 24 10 42 96

8300 1 388 171 62 395 268 777 2,063

Grand Tota 16,285 198,299 349,734 137653 89,583 42,504 245,738 1,079,796
24

Table 16. Runoff in Acre-ft/year to Streams within the Caloosahatchee Watershed

FLUCCS

Caloosahatch

ee Estuary

Freshwater 

East Freshwater West Nearshore North Coastal S-4 Tidal Grand Total

1100 43 6892 33990 9683 55055 1253 68788 175704

1200 176 1035 4749 4703 4930 4069 70559 90221

1300 50 196 1323 3268 4768 256 28216 38081

1400 27 635 2288 1400 1277 1423 22567 29612

1500 0 834 1572 21 81 4465 2378 9355

1600 0 1724 69 9 1060 212 4027 7101

1700 0 327 764 284 1481 664 7933 11456

1800 25 174 1079 2727 2375 587 6890 13857

1900 2 5064 52051 1085 14437 424 29551 102614

2110 2 91758 138540 576 5938 1988 53346 292148

2120 0 11953 26467 62 906 0 10127 49515

2130 6 12311 20850 139 172 0 8668 42144

2140 0 3142 18486 1056 663 0 4748 28093

2150 0 877 2637 17 116 79 7342 11068

2156 0 131548 5132 0 0 82124 0 218804

2160 0 0 42 0 0 0 0 42

2210 0 66316 172089 481 0 165 2055 241106

2220 0 0 0 0 0 0 30 30

2230 0 0 132 4471 15 0 357 4975

2410 0 362 231 384 0 561 478 2018

2420 0 721 7349 0 0 0 4571 12643

2430 0 40 920 399 37 0 748 2147

2500 0 0 164 0 0 35 141 343

2510 0 291 79 0 0 0 50 420

2520 0 37 0 0 0 0 79 116

2540 0 28 95 0 0 0 101 223

2610 0 332 2803 200 170 0 2002 5509

3000 83 8256 35760 5132 14844 462 31637 96176

4000 64 9714 29667 4234 13567 448 47516 105210

4400 0 16113 35415 0 86 0 1375 52990

5000 6559 857 1512 39154 2846 298 2958 54184

6000 171 18908 39596 15270 13517 744 26921 115128

7000 0 5954 6995 209 1421 2104 1602 18285

8100 25 3080 2681 150 2028 1372 11089 20428

8200 0 46 55 0 23 0 96 219

8300 2 806 355 129 821 557 1615 4287

Total (ac-ft) 7,235 400,330 645,938 95,245 142,636 104,289 460,562 1,856,254

Verification

Calculated Runoff 645,938

Measured Runoff 646,089

 (inches) 22.17
25

Table 17. Net P Loads in Pounds/year to Stream within the Caloosahatchee watershed

FLUCCS

Caloosahatc

hee Estuary

Freshwater 

East

Freshwater 

West Nearshore North Coastal S-4 Tidal Grand Total

1100 12.8 2038.7 10054.4 2864.4 16285.6 370.6 20348.2 51974.8

1200 125.6 740.0 3396.5 3363.6 3525.9 2909.6 50460.0 64521.1

1300 62.1 244.3 1647.7 4069.6 5936.8 318.8 35132.0 47415.4

1400 15.5 369.0 1329.2 813.4 741.9 826.9 13112.5 17206.4

1500 0.0 781.6 1473.8 19.9 76.2 4186.4 2229.0 8770.2

1600 0.0 503.7 20.0 2.7 309.7 61.9 1176.8 2074.8

1700 0.0 347.8 811.4 301.4 1573.2 705.5 8429.0 12171.6

1800 14.6 100.7 625.3 1580.5 1376.5 340.5 3992.9 8030.9

1900 0.4 941.7 9678.2 201.7 2684.3 78.8 5494.6 19079.7

2110 1.9 71087.9 107332.3 446.3 4600.1 1539.8 41329.3 226337.7

2120 0.0 5715.2 12654.5 29.8 433.2 0.0 4841.8 23674.5

2130 2.5 4905.1 8307.3 55.5 68.7 0.0 3453.6 16791.8

2140 0.0 3726.0 21921.3 1252.4 786.6 0.0 5630.4 33313.2

2150 0.0 1726.5 5191.6 32.7 229.1 155.5 14454.0 21789.4

2156 0.0 29118.6 1136.0 0.0 0.0 18178.5 0.0 48433.0

2160 0.0 0.0 82.1 0.0 0.0 0.0 0.0 82.1

2210 0.0 23853.9 61900.2 173.1 0.0 59.2 739.1 86725.5

2220 0.0 0.0 0.0 0.0 0.0 0.0 38.1 38.1

2230 0.0 0.0 168.2 5691.0 19.0 0.0 453.9 6332.1

2410 0.0 696.3 444.2 740.4 0.0 1080.5 920.5 3885.9

2420 0.0 805.6 8215.1 0.0 0.0 0.0 5109.7 14133.1

2430 0.0 64.0 1476.7 640.3 60.0 0.0 1200.6 3445.7

2500 0.0 0.0 198.4 0.0 0.0 42.7 170.8 414.4

2510 0.0 351.6 95.4 0.0 0.0 0.0 60.3 507.3

2520 0.0 233.0 0.0 0.0 0.0 0.0 491.9 724.9

2540 0.0 26.1 87.9 0.0 0.0 0.0 93.7 207.7

2610 0.0 128.5 1085.8 77.3 65.7 0.0 775.7 2133.9

3000 12.4 1233.6 5343.1 766.8 2218.0 69.1 4727.1 14369.9

4000 4.9 752.6 2298.4 328.1 1051.1 34.7 3681.2 8151.0

4400 0.0 2675.1 5879.4 0.0 14.3 0.0 228.3 8797.1

5000 1088.8 142.2 251.1 6500.2 472.5 49.5 491.1 8995.4

6000 3.8 418.5 876.5 338.0 299.2 16.5 595.9 2548.4

7000 0.0 1976.9 2322.5 69.3 472.0 698.6 532.0 6071.3

8100 13.7 1687.3 1468.7 82.0 1111.2 751.4 6075.0 11191.5

8200 0.0 13.2 15.9 0.0 6.6 0.0 27.8 63.6

8300 0.7 257.0 113.3 41.1 261.6 177.5 514.7 1366.5

Grand Tota 1359.6 157662.0 277902.6 30481.4 44679.0 32652.3 237011.4 781770.1

Verification Data for Freshwater West

Calculated 277,903 lbs/year

0.158 mg/l

Measured 260,240 lbs/year

0.148 mg/l
26

Table 18. Net N Loads in Pounds/year to Stream within the Caloosahatchee Watershed

FLUCCS

Caloosahatc

hee Estuary Freshwater East

Freshwater 

West Nearshore

North 

Coastal S-4 Tidal Grand Total

1100 137.9 21888.9 107948.9 30753.4 174849.8 3978.5 218467.9 558025.4

1200 686.4 4044.5 18564.5 18385.0 19272.0 15903.4 275806.1 352661.8

1300 237.6 934.6 6304.3 15570.7 22714.6 1219.7 134418.2 181415.5

1400 116.2 2773.3 9989.8 6112.9 5575.7 6214.6 98547.2 129315.1

1500 0.0 3115.2 5874.0 79.2 303.6 16684.8 8883.6 34953.6

1600 0.0 5109.7 203.3 27.7 3141.6 628.3 11938.1 21048.7

1700 0.0 970.2 2263.8 840.8 4389.0 1968.1 23515.8 33957.0

1800 101.6 702.2 4361.3 11023.3 9600.4 2374.7 27849.4 56012.9

1900 5.3 12867.4 132248.2 2756.2 36680.2 1077.1 75081.6 260715.8

2110 14.7 539120.3 813991.9 3384.6 34886.4 11677.6 313435.6 1716511.1

2120 0.0 41759.5 92463.4 217.8 3165.4 0.0 35378.0 172984.0

2130 16.2 32060.7 54298.6 362.6 449.2 0.0 22573.5 109755.4

2140 0.0 21384.0 125809.2 7187.4 4514.4 0.0 32313.6 191188.8

2150 0.0 3688.8 11092.6 69.9 489.5 332.2 30882.7 46555.7

2156 0.0 557050.6 21732.5 0.0 0.0 347761.9 0.0 926545.0

2160 0.0 0.0 246.8 0.0 0.0 0.0 0.0 246.8

2210 0.0 298373.5 774269.8 2165.5 0.0 740.5 9245.3 1084794.5

2220 0.0 0.0 0.0 0.0 0.0 0.0 142.6 142.6

2230 0.0 0.0 629.6 21300.8 71.3 0.0 1698.8 23700.6

2410 0.0 2756.2 1758.2 2930.4 0.0 4276.8 3643.2 15380.6

2420 0.0 3433.3 35010.4 0.0 0.0 0.0 21776.0 60231.6

2430 0.0 253.4 5845.0 2534.4 237.6 0.0 4752.0 13638.2

2500 0.0 0.0 834.2 0.0 0.0 179.5 718.1 1742.4

2510 0.0 2956.8 802.6 0.0 0.0 0.0 506.9 4266.2

2520 0.0 475.2 0.0 0.0 0.0 0.0 1003.2 1478.4

2540 0.0 356.4 1201.2 0.0 0.0 0.0 1280.4 2838.0

2610 0.0 1228.9 10385.8 739.2 628.3 0.0 7419.7 20411.2

3000 270.6 26876.0 116412.1 16706.8 48323.7 1504.5 102990.4 313084.2

4000 168.3 25710.3 78516.9 11206.8 35907.3 1184.7 125756.4 278450.7

4400 0.0 52880.9 116225.1 0.0 282.3 0.0 4513.5 173901.8

5000 18746.6 2448.5 4323.1 111916.7 8135.4 851.8 8455.0 154877.2

6000 544.5 60051.4 125755.7 48496.1 42930.4 2362.1 85498.4 365638.7

7000 0.0 17648.4 20734.6 619.1 4213.4 6237.0 4749.4 54201.8

8100 72.9 8998.7 7832.9 437.2 5926.3 4007.5 32400.2 59687.8

8200 0.0 158.4 190.1 0.0 79.2 0.0 332.6 760.3

8300 7.9 3073.0 1354.3 491.0 3128.4 2122.6 6153.8 16339.0

Grand Tota 21126.7 1755149.1 2709474.5 316315.7 469895.4 433287.9 1732127.1 7437458.4

Verification

Calculated 2,709,474 lbs/year

1.54 mg/l

Measured 2,468,224 lbs/year

1.41 mg/l 
27

Table 19. Land Use Categories, Unit Load Factors, and P Reduction Factors for the Caloosahatchee Watershed

Land Use Category Land Use Description FLUCCS Unit P Load 

(lbs/acre/yr)

Owner 

Implemented 

BMPs

Typical 

Incentive 

BMPs

Alternative 

Practices

Residential Low Density Residential Low Density1 1100 0.68 5% 5% 0%

Residential Medium Density Residential Medium Density2 1200 1.93 5% 5% 0%

Residential High Density Residential High Density2 1300 4.14 5% 5% 0%

Other Urban Commercial/Industrial2 1400-1800 2.05 5% 5% 0%

Improved Pastures Improved Pastures 2110 1.93 11% 19% 49%

Unimproved Pastures Unimproved Pastures 2120 0.99 7% 13% 44%

Woodland Pastures/Rangeland Woodland/Range Pastures 2130/3000 0.40 4% 6% 35%

Row Crops Row Crops 2140 3.45 30% 30% 50%

Sugar Cane Sugar Cane 2156 0.55 10% 23% 52%

Citrus Citrus 2210 0.90 12% 20% 42%

Sod Farms Sod Farms 2420 2.79 20% 27% 50%

Ornamentals Ornamentals 2430 4.00 32% 35% 50%

Horse Farms Horse Farms 2510 2.51 20% 22% 49%

Dairies Dairies 2520 12.94 9% 28% 48%

Other Areas Other Areas 2150-2610 3.20 15% 25% 36%

Tree Plantations Tree Plantations 4400 0.21 1% 10% 50%

Water Water 5000 0.07 0% 0% 0%

Natural Areas Forrests/wetlands/Open 4000/6000 0.11 0% 0% 0%

Transportation Transportation 8100 2.28 10% 23% 52%

Communication/Utilities Communication/Utilities 8200/8300 0.66 5% 5% 0%

1 Assumed on Septic

2 Assumed about 70% of Discharge from WWT outside basin

Estimated Phosphorus Reduction
28

Table 20. Land Use Categories, Unit Load Factors, and Estimated P Reduction Factors Using 2004 Land Use

 for the Caloosahatchee Watershed

Land Use Category Land Use Description FLUCCS Percent 

of Basin

Unit P Load Total P Annual Cost 

(lbs/acre/yr) (MT/yr) (percent) (MT/yr) ($)

Residential Low Density Residential Low Density1 1100 7.12% 0.68 23.6 10% 2.4 176,305,275

Residential Medium Density Residential Medium Density2 1200 3.09% 1.93 29.3 10% 2.9 76,602,409

Residential High Density Residential High Density2 1300 1.06% 4.14 21.6 10% 2.2 26,270,433

Other Urban Commercial/Industrial2 1400-1800 2.18% 2.05 21.9 10% 2.2 54,061,629

Improved Pastures Improved Pastures 2110 10.85% 1.93 102.9 30% 30.9 2,078,370

Unimproved Pastures Unimproved Pastures 2120 2.21% 0.99 10.8 20% 2.2 112,723

Woodland Pastures/Rangeland Woodland/Range Pastures 2130/3000 7.24% 0.40 14.2 10% 1.4 369,624

Row Crops Row Crops 2140 0.89% 3.45 15.1 60% 9.1 761,356

Sugar Cane Sugar Cane 2156 8.13% 0.55 22.0 33% 7.3 3,459,101

Citrus Citrus 2210 8.95% 0.90 39.4 32% 12.6 8,121,456

Sod Farms Sod Farms 2420 0.47% 2.79 6.4 47% 3.0 199,880

Ornamentals Ornamentals 2430 0.08% 4.00 1.6 67% 1.0 67,888

Horse Farms Horse Farms 2510 0.02% 2.51 0.2 42% 0.1 3,345

Dairies Dairies 2520 0.01% 12.94 0.3 37% 0.1 65,542

Other Areas Other Areas 2150-2610 1.01% 3.20 15.9 40% 6.3 193,552

Tree Plantations Tree Plantations 4400 3.94% 0.21 4.0 11% 0.4 1,204,103

Water Water 5000 12.07% 0.07 4.1 0% 0.0 0

Natural Areas Forrests/wetlands/Open 4000/6000 30.03% 0.11 16.3 0% 0.0 0

Transportation Transportation 8100 0.46% 2.28 5.1 33% 1.7 193,769

Communication/Utilities Communication/Utilities 8200/8300 0.20% 0.66 0.7 10% 0.1 1,602,248

Total Basin 100% 0.68 334 25% 84 325,402,270

1 Assumed on Septic

2 Assumed about 70% of Discharge from WWT outside basin

Estimated P 

Reduction
29

Table 21. Land Use Categories, Unit Load Factors, and N Reduction Factors for the Caloosahatchee Watershed

Land Use Category Land Use Description FLUCCS Unit N Load 

(lbs/acre/yr)

Owner 

Implemented 

BMPs

Typical 

Incentive 

BMPs

Alternative 

Practices

Residential Low Density Residential Low Density1 1100 7.26 15% 15% 15%

Residential Medium Density Residential Medium Density2 1200 10.56 25% 25% 15%

Residential High Density Residential High Density2 1300 15.84 30% 25% 15%

Other Urban Commercial/Industrial2 1400-1800 11.68 25% 25% 15%

Improved Pastures Improved Pastures 2110 14.65 17% 10% 30%

Unimproved Pastures Unimproved Pastures 2120 7.26 11% 8% 30%

Woodland Pastures/Rangeland Woodland/Range Pastures 2130/3000 5.41 4% 6% 20%

Row Crops Row Crops 2140 19.80 30% 30% 50%

Sugar Cane Sugar Cane 2156 10.56 10% 23% 52%

Citrus Citrus 2210 11.22 10% 20% 42%

Sod Farms Sod Farms 2420 11.88 20% 27% 50%

Ornamentals Ornamentals 2430 15.84 25% 25% 25%

Horse Farms Horse Farms 2510 21.12 30% 22% 30%

Dairies Dairies 2520 26.40 20% 40% 48%

Other Areas Other Areas 2150-2610 10.18 15% 25% 36%

Tree Plantations Tree Plantations 4400 4.09 5% 10% 25%

Water Water 5000 1.19 0% 0% 0%

Natural Areas Forrests/wetlands/Open 4000/6000 2.96 0% 0% 0%

Transportation Transportation 8100 12.14 20% 23% 25%

Communication/Utilities Communication/Utilities 8200/8300 7.92 30% 25% 15%

1 Assumed on Septic

2 Assumed about 70% of Discharge from WWT outside basin

Estimated Nitrogen Reduction
30

Table 22. Land Use Categories, Unit Load Factors, and Estimated N Reduction Factors Using 2004 Land Use

 for the Caloosahatchee Watershed

Land Use Category Land Use Description FLUCCS Percent 

of Basin

Unit N Load Total N Annual Cost 

(lbs/acre/yr) (MT/yr) (percent) (MT/yr) ($)

Residential Low Density Residential Low Density1 1100 7.12% 7.26 253.6 30% 76.1 176,608,300

Residential Medium Density Residential Medium Density2 1200 3.09% 10.56 160.3 50% 80.2 76,781,946

Residential High Density Residential High Density2 1300 1.06% 15.84 82.5 55% 45.4 26,332,005

Other Urban Commercial/Industrial2 1400-1800 2.18% 11.68 125.1 55% 68.8 59,607,170

Improved Pastures Improved Pastures 2110 10.85% 14.65 780.2 27% 210.7 2,078,370

Unimproved Pastures Unimproved Pastures 2120 2.21% 7.26 78.6 19% 14.9 101,987

Woodland Pastures/Rangeland Woodland/Range Pastures 2130/3000 7.24% 5.41 192.2 10% 19.2 369,624

Row Crops Row Crops 2140 0.89% 19.80 86.9 60% 52.1 761,356

Sugar Cane Sugar Cane 2156 8.13% 10.56 421.2 33% 139.0 3,484,258

Citrus Citrus 2210 8.95% 11.22 493.1 30% 147.9 16,979,257

Sod Farms Sod Farms 2420 0.47% 11.88 27.4 47% 12.9 199,880

Ornamentals Ornamentals 2430 0.08% 15.84 6.2 50% 3.1 50,663

Horse Farms Horse Farms 2510 0.02% 21.12 1.9 52% 1.0 3,584

Dairies Dairies 2520 0.01% 26.40 0.7 60% 0.4 65,542

Other Areas Other Areas 2150-2610 1.01% 10.18 50.5 40% 20.2 226,788

Tree Plantations Tree Plantations 4400 3.94% 4.09 79.0 15% 11.9 1,427,933

Water Water 5000 12.07% 1.19 70.4 0% 0.0 0

Natural Areas Forrests/wetlands/Open 4000/6000 30.03% 2.96 435.9 0% 0.0 0

Transportation Transportation 8100 0.46% 12.14 27.1 43% 11.7 256,618

Communication/Utilities Communication/Utilities 8200/8300 0.20% 7.92 7.8 55% 4.3 3,702,458

Total Basin 100% 6.72 3,298 27% 874 342,705,734

1 Assumed on Septic

2 Assumed about 70% of Discharge from WWT outside basin

Estimated N 

Reduction