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: 2,406 acres
  • Location: North Sarasota County
  • Discharges into: Sarasota Bay

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

View county-wide water quality trends »

Hudson Bayou

Hudson Bayou

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:
  • 1953A
Chart Legend
  • Trend Line
  • Annual Mean
  • Threshold
Pass

Chlorophyll a

Score: Pass
Units: mg/l Year
2019
Historical
period of record
High 0.024 0.1568
Mean 0.0012 0.0013 0.01246593
Low 0.0004 0.0002
No. of Samples 50 696

Five-year Rolling Average

  • Annual Mean
Pass

Nitrogen, Total

Score: Pass
Units: mg/l Year
2019
Historical
period of record
High 3.303 17.52
Mean 1.0106 0.9034 1.2264874
Low 0.625 0.0018
No. of Samples 49 406

Five-year Rolling Average

  • Annual Mean
Pass

Phosphorus, Total

Score: Pass
Units: mg/l Year
2019
Historical
period of record
High 1.80 4.05
Mean 0.3081 0.4361 0.36993906
Low 0.047 0.047
No. of Samples 49 715

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
2019
Historical
period of record
High 96.10 144.70
Mean 63.45 53.07 30.06137
Low 22.60 3.30
No. of Samples 25 713

Five-year Rolling Average

  • Annual Mean

BOD, Biochemical oxygen demand

Units: mg/l Year
2019
Historical
period of record
High 1.32 13.10
Mean 1.03 0.98 1.63595
Low 1.00 0.50
No. of Samples 44 677

Five-year Rolling Average

  • Annual Mean

Color

Units: PCU Year
2019
Historical
period of record
High 120.00 400.00
Mean 72.23 72.45 34.38452
Low 40.00 20.00
No. of Samples 49 796

Five-year Rolling Average

  • Annual Mean

Escherichia coli

Units: cfu/100ml Year
2019
Historical
period of record
High 5475.00 10462.00
Mean 1414.99 1228.53 1864.67299
Low 315.00 41.00
No. of Samples 48 218

Five-year Rolling Average

  • Annual Mean

Nitrogen, Ammonia + Ammonium as N

Units: ug/l Year
2019
Historical
period of record
High 309.00 650.00
Mean 57.08 52.68 110.44038
Low 8.00 0.008
No. of Samples 49 737

Five-year Rolling Average

  • Annual Mean

Nitrogen, Kjeldahl

Units: ug/l Year
2019
Historical
period of record
High 3060.00 13800.00
Mean 821.72 782.02 795.51706
Low 446.00 0.00
No. of Samples 49 714

Five-year Rolling Average

  • Annual Mean

Nitrogen, Nitrite + Nitrate as N

Units: ug/l Year
2019
Historical
period of record
High 344.00 3720.00
Mean 164.72 121.4 234.02298
Low 44.00 4.00
No. of Samples 49 715

Five-year Rolling Average

  • Annual Mean

pH

Units: None Year
2019
Historical
period of record
High 7.64 758.00
Mean 7.26 7.46 28.59633
Low 6.94 6.62
No. of Samples 25 689

Five-year Rolling Average

  • Annual Mean

Rainfall

Units: inches Year
2019
Historical
period of record
High 34.76 63.64
Mean 14.0989372707216
Low 11.33
No. of Samples 363 6,447

Five-year Rolling Average

  • Annual Mean

Salinity

Units: PSS Year
2019
Historical
period of record
High 0.7868 25.30
Mean 0.36 0.37 2.2378
Low 0.1918 0.04
No. of Samples 26 591

Five-year Rolling Average

  • Annual Mean

Specific conductance

Units: umho Year
2019
Historical
period of record
High 1545.48 54000.00
Mean 735.44 821.54 8812.04256
Low 396.645 0.445
No. of Samples 25 617

Five-year Rolling Average

  • Annual Mean

Temperature, water

Units: deg F Year
2019
Historical
period of record
High 85.5685 91.40
Mean 76.67 73.61 7.24582
Low 64.8426 53.87
No. of Samples 25 515

Five-year Rolling Average

  • Annual Mean

Turbidity

Units: NTU Year
2019
Historical
period of record
High 60.00 60.00
Mean 60.0 3.73 4.56997
Low 60.00 1.00
No. of Samples 1 610

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 »

Chart Legend
  • Trend Line
  • Annual Mean
  • Threshold
Water quality data are not available for the tidal portion of this creek.

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 HUD2 2019 18 82 100 82

Impervious Features

Hudson Bayou is located within the Sarasota Bay Watershed. View details about the 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.

47% of the land area within the Hudson Bayou Basin is covered by impervious surfaces

Impervious Surface Coverage by Type

Land Use / Land Cover

Hudson Bayou is located within the Sarasota Bay Watershed. View details about the 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 Hudson Bayou Basin
Land Use Classification 1990 1995 1999 2005 2011 2014 2017 2020 Trend
Urban & Built-up 2,22492.4% 2,24493.3% 2,24393.2% 2,26093.9% 2,26093.9% 2,24993.5% 2,26093.9% 2,25993.9% Land Use Trend Sparkline
Upland Forests 160.7% 90.4% 90.4% 00% 00% 00% 00% 00% Land Use Trend Sparkline
Water 241% 251% 261.1% 261.1% 271.1% 271.1% 271.1% 271.1% Land Use Trend Sparkline
Wetlands 160.7% 130.5% 130.5% 100.4% 100.4% 100.4% 100.4% 100.4% Land Use Trend Sparkline
Transportation and Utilities 1265.2% 1154.8% 1154.8% 1094.6% 1094.6% 1205% 1094.5% 1104.6% Land Use Trend Sparkline
Land Use Chart