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

2 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: 2,327 acres
  • Location: Central Sarasota County
  • Discharges into: Little Sarasota Bay

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

View county-wide water quality trends »

North Creek

North 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:
  • 1984AB
Chart Legend
  • Trend Line
  • Annual Mean
  • Threshold

Chlorophyll a

Units: mg/l Year
2022
Historical
period of record
High 0.032
Mean 0.0035 0.00706059
Low 0.0007
No. of Samples 0 49

Five-year Rolling Average

  • Annual Mean

Nitrogen, Total

Units: mg/l Year
2022
Historical
period of record
High 3.71
Mean 1.4122 0.56145996
Low 1.042
No. of Samples 0 29

Five-year Rolling Average

  • Annual Mean

Phosphorus, Total

Units: mg/l Year
2022
Historical
period of record
High 2.70
Mean 0.1679 0.46026575
Low 0.041
No. of Samples 0 33

Five-year Rolling Average

  • Annual Mean

Dissolved Oxygen Saturation

Note: Low DO saturation also may be naturally influenced by inflows from nearby wetlands or groundwater sources.
Units: percent (%) Year
2022
Historical
period of record
High 117.00
Mean 45.36 19.76586
Low 10.70
No. of Samples 0 60

Five-year Rolling Average

  • Annual Mean

BOD, Biochemical oxygen demand

Units: mg/l Year
2022
Historical
period of record
High 1.70
Mean 1.54 0.21213
Low 1.40
No. of Samples 0 2

Five-year Rolling Average

  • Annual Mean

Color

Units: PCU Year
2022
Historical
period of record
High 250.00
Mean 85.47 46.11282
Low 38.00
No. of Samples 0 30

Five-year Rolling Average

  • Annual Mean

Escherichia coli

Units: cfu/100ml Year
2022
Historical
period of record
High 866.00
Mean 214.63 203.21843
Low 74.00
No. of Samples 0 15

Five-year Rolling Average

  • Annual Mean

Nitrogen, Ammonia + Ammonium as N

Units: ug/l Year
2022
Historical
period of record
High 460.00
Mean 69.41 77.23173
Low 18.00
No. of Samples 0 30

Five-year Rolling Average

  • Annual Mean

Nitrogen, Kjeldahl

Units: ug/l Year
2022
Historical
period of record
High 27000.00
Mean 1317.06 4731.13119
Low 890.00
No. of Samples 0 30

Five-year Rolling Average

  • Annual Mean

Nitrogen, Nitrite + Nitrate as N

Units: ug/l Year
2022
Historical
period of record
High 520.00
Mean 108.07 171.34175
Low 4.00
No. of Samples 0 30

Five-year Rolling Average

  • Annual Mean

pH

Units: None Year
2022
Historical
period of record
High 7.72
Mean 7.3 0.18823
Low 6.80
No. of Samples 0 60

Five-year Rolling Average

  • Annual Mean

Salinity

Units: PSS Year
2022
Historical
period of record
High 14.86
Mean 0.64 2.43739
Low 0.16
No. of Samples 0 58

Five-year Rolling Average

  • Annual Mean

Specific conductance

Units: umho Year
2022
Historical
period of record
High 24590.00
Mean 1265.22 3943.77213
Low 328.00
No. of Samples 0 60

Five-year Rolling Average

  • Annual Mean

Temperature, water

Units: deg F Year
2022
Historical
period of record
High 85.028
Mean 75.48 6.54002
Low 55.94
No. of Samples 0 60

Five-year Rolling Average

  • Annual Mean

Turbidity

Units: NTU Year
2022
Historical
period of record
High 39.00
Mean 4.46 8.8722
Low 1.30
No. of Samples 0 30

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:
  • 1984A
Chart Legend
  • Trend Line
  • Annual Mean
  • Threshold
Caution

Chlorophyll a

Score: Caution
Units: mg/l Year
2022
Historical
period of record
High 0.1 0.2
Mean 0.0129 0.0125 0.02211634
Low 0.0043 0.0009
No. of Samples 12 300

Five-year Rolling Average

  • Annual Mean

Nitrogen, Total

We were unable to determine a trend for the data available.
Units: mg/l Year
2022
Historical
period of record
High 2.0 4.0
Mean 1.4583 1.3038 0.42602326
Low 1.085 0.002
No. of Samples 12 261

Five-year Rolling Average

  • Annual Mean

Phosphorus, Total

We were unable to determine a trend for the data available.
Units: mg/l Year
2022
Historical
period of record
High 0.4 0.9
Mean 0.2326 0.2819 0.14560358
Low 0.145 0.08
No. of Samples 12 308

Five-year Rolling Average

  • Annual Mean
Caution

Dissolved Oxygen Saturation

Note: Low DO saturation also may be naturally influenced by inflows from nearby wetlands or groundwater sources
Score: Caution
Units: percent (%) Year
2022
Historical
period of record
High 58.5 157.4
Mean 8.21 27.63 23.74285
Low 1.629 0.70
No. of Samples 12 382

Five-year Rolling Average

  • Annual Mean

BOD, Biochemical oxygen demand

Units: mg/l Year
2022
Historical
period of record
High 4.3 14.5
Mean 1.36 1.74 1.6532
Low 1.00 0.50
No. of Samples 12 242

Five-year Rolling Average

  • Annual Mean

Color

Units: PCU Year
2022
Historical
period of record
High 140.0 300.0
Mean 89.11 81.44 37.6399
Low 50.00 5.00
No. of Samples 12 397

Five-year Rolling Average

  • Annual Mean

Enterococcus Group Bacteria

Units: cfu/100ml Year
2022
Historical
period of record
High 5,400.0 20,000.0
Mean 721.23 890.86 3051.99494
Low 200.00 63.00
No. of Samples 12 141

Five-year Rolling Average

  • Annual Mean

Nitrogen, Ammonia + Ammonium as N

Units: ug/l Year
2022
Historical
period of record
High 487.0 602.0
Mean 34.87 22.68 95.17026
Low 8.00 0.008
No. of Samples 12 372

Five-year Rolling Average

  • Annual Mean

Nitrogen, Kjeldahl

Units: ug/l Year
2022
Historical
period of record
High 1,960.0 2,860.0
Mean 1331.22 1215.39 385.11961
Low 944.00 50.00
No. of Samples 12 355

Five-year Rolling Average

  • Annual Mean

Nitrogen, Nitrite + Nitrate as N

Units: ug/l Year
2022
Historical
period of record
High 249.0 2,380.0
Mean 76.34 98.31 207.9885
Low 6.00 0.00
No. of Samples 12 314

Five-year Rolling Average

  • Annual Mean

pH

Units: None Year
2022
Historical
period of record
High 7.3 8.8
Mean 7.05 7.42 0.32132
Low 6.40 5.40
No. of Samples 12 440

Five-year Rolling Average

  • Annual Mean

Salinity

Units: PSS Year
2022
Historical
period of record
High 29.8 29.8
Mean 8.55 6.47 8.45661
Low 0.655 0.00
No. of Samples 12 391

Five-year Rolling Average

  • Annual Mean

Specific conductance

Units: umho Year
2022
Historical
period of record
High 48,170.6 650,900.0
Mean 14382.15 11890.28 32354.205
Low 1297.17 25.058
No. of Samples 12 467

Five-year Rolling Average

  • Annual Mean

Temperature, water

Units: deg F Year
2022
Historical
period of record
High 189.1 190.1
Mean 172.72 83.45 29.313
Low 145.7492 48.56
No. of Samples 12 385

Five-year Rolling Average

  • Annual Mean

Turbidity

Units: NTU Year
2022
Historical
period of record
High 30.0
Mean 4.94 3.40511
Low 1.20
No. of Samples 0 300

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 NO1 2022 95 212 307 69

Impervious Features

North 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.

15% of the land area within the North Creek Basin is covered by impervious surfaces

Impervious Surface Coverage by Type

Land Use / Land Cover

North 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 North Creek Basin
Land Use Classification 1990 1995 1999 2005 2011 2014 2017 2020 Trend
Urban & Built-up 1,07446.2% 1,58468.1% 1,65271% 1,70273.2% 1,69973% 1,67972.2% 1,79577.1% 1,80977.8% Land Use Trend Sparkline
Agriculture 793.4% 863.7% 180.8% 90.4% 40.2% 1225.2% 40.2% 40.2% Land Use Trend Sparkline
Rangeland 00% 00% 00% 753.2% 743.2% 200.9% 301.3% 00% Land Use Trend Sparkline
Upland Forests 84536.3% 27511.8% 27711.9% 1426.1% 1416.1% 974.2% 944.1% 903.9% Land Use Trend Sparkline
Water 773.3% 1616.9% 1807.8% 1807.7% 1777.6% 1777.6% 1827.8% 1978.5% Land Use Trend Sparkline
Wetlands 2169.3% 2018.6% 1797.7% 1787.7% 1918.2% 1918.2% 1827.8% 1847.9% Land Use Trend Sparkline
Barren Land 170.7% 00% 00% 00% 10% 00% 00% 00% Land Use Trend Sparkline
Transportation and Utilities 180.8% 200.8% 200.8% 401.7% 401.7% 401.7% 401.7% 431.8% Land Use Trend Sparkline
Land Use Chart