Pass
Rating icon - Chlorophyll a Rating icon - Total Nitrogen Rating icon - Total Phosphorous Rating icon - Dissolved Oxygen Saturation

4 out of 4 indicators were rated as PASS.

All four indicators must pass for the creek to be rated as PASS.

Learn more about how this report is created

  • Size: 12,630 acres
  • Location: Central Sarasota County
  • Discharges into: Blackburn Bay

For more information, please see: Little Sarasota Bay Water Quality Management Plan (2012)

View county-wide water quality trends »

South Creek

South Creek

Water Chemistry Ratings | Freshwater Portion of the Creek

Creek Conditions Ratings are based on comparing nitrogen, phosphorus, chlorophyll and dissolved oxygen to water quality guidelines or regulations. Florida law defines a maximum allowable concentration of nitrogen, phosphorus, and chlorophyll a, and a minimum allowable concentration of dissolved oxygen in these streams. Learn more about these ratings and how they are calculated »

Data for the following WBIDs is averaged when compiling the data below:
  • 1982
  • 1982B
  • 1985
Chart Legend
  • Trend Line
  • Annual Mean
  • Threshold
Pass

Chlorophyll a

Score: Pass
Units: mg/l Year
2022
Historical
period of record
High 0.0354 0.0416
Mean 0.0026 0.0046 0.00624948
Low 0.0005 0.0003
No. of Samples 12 318

Five-year Rolling Average

  • Annual Mean
Pass

Nitrogen, Total

Score: Pass
Units: mg/l Year
2022
Historical
period of record
High 1.956 3.60
Mean 1.3868 1.1323 0.55348047
Low 0.67 0.0022
No. of Samples 12 285

Five-year Rolling Average

  • Annual Mean
Pass

Phosphorus, Total

Score: Pass
Units: mg/l Year
2022
Historical
period of record
High 0.185 1.308
Mean 0.0681 0.1499 0.17406027
Low 0.024 0.01
No. of Samples 12 318

Five-year Rolling Average

  • Annual Mean
Pass

Dissolved Oxygen Saturation

Note: Low DO saturation also may be naturally influenced by inflows from nearby wetlands or groundwater sources.
Score: Pass
Units: percent (%) Year
2022
Historical
period of record
High 76.5457 135.60
Mean 39.78 47.76 21.40413
Low 12.8043 1.80
No. of Samples 16 380

Five-year Rolling Average

  • Annual Mean

BOD, Biochemical oxygen demand

Units: mg/l Year
2022
Historical
period of record
High 1.78 8.49
Mean 1.05 1.2 0.9154
Low 1.00 0.50
No. of Samples 12 246

Five-year Rolling Average

  • Annual Mean

Color

Units: PCU Year
2022
Historical
period of record
High 300.00 450.00
Mean 91.73 103.89 74.27878
Low 40.00 10.00
No. of Samples 12 423

Five-year Rolling Average

  • Annual Mean

Escherichia coli

Units: cfu/100ml Year
2022
Historical
period of record
High 275.00 8164.00
Mean 62.62 104.35 908.26868
Low 10.00 9.10
No. of Samples 16 152

Five-year Rolling Average

  • Annual Mean

Nitrogen, Ammonia + Ammonium as N

Units: ug/l Year
2022
Historical
period of record
High 741.00 741.00
Mean 21.53 20.18 103.89011
Low 8.00 0.00
No. of Samples 12 384

Five-year Rolling Average

  • Annual Mean

Nitrogen, Kjeldahl

Units: ug/l Year
2022
Historical
period of record
High 1910.00 3110.00
Mean 1276.25 1110.73 481.02269
Low 586.00 129.00
No. of Samples 12 365

Five-year Rolling Average

  • Annual Mean

Nitrogen, Nitrite + Nitrate as N

Units: ug/l Year
2022
Historical
period of record
High 234.00 1810.00
Mean 87.07 66.14 161.83998
Low 15.00 0.00
No. of Samples 12 325

Five-year Rolling Average

  • Annual Mean

pH

Units: None Year
2022
Historical
period of record
High 7.4485 8.88
Mean 6.88 7.48 0.28615
Low 5.85 3.00
No. of Samples 16 1,989

Five-year Rolling Average

  • Annual Mean

Salinity

Units: PSS Year
2022
Historical
period of record
High 0.6727 38.60
Mean 0.47 8.09 12.58246
Low 0.28 0.00
No. of Samples 20 1,912

Five-year Rolling Average

  • Annual Mean

Specific conductance

Units: umho Year
2022
Historical
period of record
High 1330.70 55148.00
Mean 952.01 10183.48 15389.11176
Low 574.612 0.00
No. of Samples 16 1,994

Five-year Rolling Average

  • Annual Mean

Temperature, water

Units: deg F Year
2022
Historical
period of record
High 181.9014 185.1029
Mean 138.08 78.63 14.3628
Low 72.32 34.574
No. of Samples 16 1,914

Five-year Rolling Average

  • Annual Mean

Turbidity

Units: NTU Year
2022
Historical
period of record
High 280.00
Mean 4.12 16.28289
Low 0.42
No. of Samples 0 305

Five-year Rolling Average

  • Annual Mean
Other Measures of Creek Health:

Water Chemistry Ratings | Tidal Portion of the Creek

Creek Conditions Ratings are based on comparing nitrogen, phosphorus, chlorophyll and dissolved oxygen to water quality guidelines or regulations. Florida law defines a maximum allowable concentration of chlorophyll a and a minimum allowable concentration of dissolved oxygen in these streams. Florida has no regulatory thresholds for nitrogen or phosphorus in tidal creeks so trends are used to rate the creeks. Learn more about these ratings and how they are calculated »

Data for the following WBIDs is averaged when compiling the data below:
  • 1982A
  • 1992
Chart Legend
  • Trend Line
  • Annual Mean
  • Threshold

Chlorophyll a

Units: mg/l Year
2022
Historical
period of record
High 0.0
Mean 0.0055 0.01042251
Low 0.0001
No. of Samples 0 42

Five-year Rolling Average

  • Annual Mean

Nitrogen, Total

Units: mg/l Year
2022
Historical
period of record
High 2.6
Mean 1.0356 0.5517367
Low 0.049
No. of Samples 0 70

Five-year Rolling Average

  • Annual Mean

Phosphorus, Total

Units: mg/l Year
2022
Historical
period of record
High 1.6
Mean 0.3068 0.22696825
Low 0.06
No. of Samples 0 79

Five-year Rolling Average

  • Annual Mean

Dissolved Oxygen Saturation

Units: percent (%) Year
2022
Historical
period of record
High 101.2
Mean 51.02 19.99828
Low 9.00
No. of Samples 0 168

Five-year Rolling Average

  • Annual Mean

BOD, Biochemical oxygen demand

Units: mg/l Year
2022
Historical
period of record
High 8.3
Mean 2.81 2.004
Low 0.78
No. of Samples 0 23

Five-year Rolling Average

  • Annual Mean

Color

Units: PCU Year
2022
Historical
period of record
High 280.0
Mean 54.99 63.54005
Low 15.00
No. of Samples 0 128

Five-year Rolling Average

  • Annual Mean

Nitrogen, Ammonia + Ammonium as N

Units: ug/l Year
2022
Historical
period of record
High 290.0
Mean 5.09 43.08657
Low 0.00
No. of Samples 0 129

Five-year Rolling Average

  • Annual Mean

Nitrogen, Kjeldahl

Units: ug/l Year
2022
Historical
period of record
High 4,720.0
Mean 1017.45 577.66121
Low 0.00
No. of Samples 0 130

Five-year Rolling Average

  • Annual Mean

Nitrogen, Nitrite + Nitrate as N

Units: ug/l Year
2022
Historical
period of record
High 430.0
Mean 36.86 92.34682
Low 0.00
No. of Samples 0 91

Five-year Rolling Average

  • Annual Mean

pH

Units: None Year
2022
Historical
period of record
High 8.8
Mean 7.6 0.36242
Low 5.80
No. of Samples 0 186

Five-year Rolling Average

  • Annual Mean

Salinity

Units: PSS Year
2022
Historical
period of record
High 34.6
Mean 14.91 10.16399
Low 0.00
No. of Samples 0 121

Five-year Rolling Average

  • Annual Mean

Specific conductance

Units: umho Year
2022
Historical
period of record
High 54,000.0
Mean 18372.16 16217.39383
Low 230.00
No. of Samples 0 252

Five-year Rolling Average

  • Annual Mean

Temperature, water

Units: deg F Year
2022
Historical
period of record
High 89.6
Mean 74.92 8.10019
Low 52.70
No. of Samples 0 169

Five-year Rolling Average

  • Annual Mean

Turbidity

Units: NTU Year
2022
Historical
period of record
High 23.0
Mean 3.31 3.71898
Low 0.65
No. of Samples 0 144

Five-year Rolling Average

  • Annual Mean
Other Measures of Creek Health:

Oysters

Because they are immobile and will tolerate a fairly wide salinity range, eastern oysters (Crassostrea virginica) are valuable as an indicator of the relative health of aquatic ecosystems in the tidally-influenced portions of coastal creeks. Sarasota County has established an oyster monitoring program to track the location, types, and status of oyster reefs. Data from this monitoring program is shown below. Learn more about Oysters »

Loading oyster site map...
Most Recent Sarasota County Oyster Monitoring Program Data
Icon Site ID Year Dead Live Total % Live
1 SC1 2022 63 182 245 74
2 SC2 2022 201 368 569 64

Impervious Features

South Creek is located within the Little Sarasota Bay Watershed. View details about the Little Sarasota Bay Watershed »

Rain that falls on land that is in a natural state is absorbed and filtered by soils and vegetation as it makes it way into underground aquifers. However, in developed areas, "impervious surfaces" impede this process and contribute to polluted urban runoff entering surface waters. These surfaces include human infrastructure like roads, sidewalks, driveways and parking lots that are covered by impenetrable materials such as asphalt, concrete, brick and stone, as well as buildings and other permanent structures. Soils that have been disturbed and compacted by urban development are often impervious as well. Learn more about Impervious Features »

The Sarasota County Stormwater Environmental Utility (SEU) mapped impervious surfaces in the County in 2013. A map showing impervious surfaces can be viewed using the Water Atlas Map Viewer tool.

6% of the land area within the South Creek Basin is covered by impervious surfaces

Impervious Surface Coverage by Type

Land Use / Land Cover

South Creek is located within the Little Sarasota Bay Watershed. View details about the Little Sarasota Bay Watershed »

Land use within a creek's watershed has a major effect on its water quality. In general, less development means better water quality. Land Cover/Land Use classifications categorize land in terms of its observed physical surface characteristics (e.g. upland or wetland), and also reflect the types of activity that are taking place on it (agriculture, urban/built-up, utilities, etc.). Florida uses as its standard a set of statewide classifications which were developed by the Florida Department of Transportation. Learn more about Land Use and Land Cover »

Acreage and Percentage within each Land Use / Land Cover Category for South Creek Basin
Land Use Classification 1990 1995 1999 2005 2011 2014 2017 2020 Trend
Urban & Built-up 1,1298.9% 1,36910.8% 1,74513.8% 2,34118.5% 2,54620.2% 2,75621.8% 2,99523.7% 3,52527.9% Land Use Trend Sparkline
Agriculture 2,79022.1% 3,03524% 3,10424.6% 3,03124% 3,08824.5% 3,79330% 2,97923.6% 2,71921.5% Land Use Trend Sparkline
Rangeland 6495.1% 1,45211.5% 1,72313.6% 1,56512.4% 1,1819.4% 4843.8% 1,0408.2% 7155.7% Land Use Trend Sparkline
Upland Forests 4,91638.9% 3,58528.4% 2,78922.1% 2,39819% 2,40919.1% 2,15517.1% 2,21617.5% 2,14417% Land Use Trend Sparkline
Water 2261.8% 5414.3% 4383.5% 6054.8% 6275% 6545.2% 6835.4% 7836.2% Land Use Trend Sparkline
Wetlands 2,55320.2% 2,22517.6% 2,40319% 2,29018.1% 2,32018.4% 2,32118.4% 2,26417.9% 2,24317.8% Land Use Trend Sparkline
Barren Land 00% 110.1% 130.1% 100.1% 180.1% 200.2% 60% 60% Land Use Trend Sparkline
Transportation and Utilities 3672.9% 4123.3% 4153.3% 3903.1% 4403.5% 4453.5% 4483.5% 4963.9% Land Use Trend Sparkline
Land Use Chart