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Sarasota Bay Condition Report for 2017

View 2016 Report

Pass

3 out of 3 indicators were rated as PASS.

All three indicators must pass
for the bay to be rated as PASS.

Learn more about how this report is created

Summary:

The overall health in Sarasota Bay showed improvement in 2017, with concentrations of both chlorophyll a and phosphorus lower than in 2016. Nitrogen levels increased slightly, but are still relatively low.

Water Quality: The mean concentration of chlorophyll a in Sarasota Bay fell to 0.0056 mg/l in 2017, bringing it below the threshold value and improving its rating to "Good". Phosphorus levels, already low, were also down from 2016, and at 0.0598 mg/l remain below the target. Nitrogen concentration rose slightly to 0.3666 mg/l, but water quality overall remained very good. The target and threshold values for nitrogen in Sarasota Bay are still advisory, as no official regulatory threshold has been established. The mean for chlorophyll a was calculated as an arithmetic mean and the means for nitrogen and phosphorus were calculated as geometric means (per the Numeric Nutrient Criteria outlined in the Florida Administrative Code, section 62-302.532). 

Biotic Indicator: A survey of the biotic indicator, seagrass, was performed in 2016 by the Southwest Florida Water Management District. In 2016, the total area of seagrass in the lower portion of Sarasota Bay (the area within Sarasota County) was estimated to be 3,639 acres, well above the target of 2,022 acres.

Bay Location Map

Bays included in this report:

Water Chemistry Ratings

Total nitrogen, total phosphorus, and chlorophyll a levels are monitored carefully by water resource managers and used by regulatory authorities to determine whether a bay meets the water quality standards mandated by the Clean Water Act. The trend graphs for these indicators are shown below, along with their target and threshold values. A target value is a desirable goal to be attained, while a threshold is an undesirable level which is to be avoided. Learn More about these ratings and how they are calculated »

The Five-year Trend Graphs below illustrate the general trend of water quality parameters. They show a six-month running average, which moderates high and low values in the data.

Good

Chlorophyll a

Units: mg/l Year
2017
Historical
period of record
High 0.0276 0.049
Mean 0.0056 0.0048 0.00393333 0.0052000000
Low 0.0008 0.0002
No. of Samples 252 8,275

Five-year Trend Graph

     
1/1/20134.12450.0052000mg/l
2/1/20132.19430.0040800mg/l
3/1/20134.30370.0038000mg/l
4/1/20134.02460.0037100mg/l
5/1/20133.79420.0037100mg/l
6/1/20135.91420.0040600mg/l
7/1/20133.95410.0040300mg/l
8/1/20135.75410.0046200mg/l
9/1/20135.34370.0047900mg/l
10/1/20136.23460.0051600mg/l
11/1/20134.13370.0052200mg/l
12/1/20133.67460.0048500mg/l
1/1/20142.94370.0046800mg/l
2/1/20142.04450.0040600mg/l
3/1/20142.29410.0035500mg/l
4/1/20143.72420.0031300mg/l
5/1/20143.13370.0029700mg/l
6/1/20144.69460.0031400mg/l
7/1/20148.53410.0040700mg/l
8/1/20145.17370.0045900mg/l
9/1/20147.09370.0053900mg/l
10/1/20145.19510.0056300mg/l
11/1/20143.37410.0056700mg/l
12/1/20146.57430.0059900mg/l
1/1/20154.41620.0053000mg/l
2/1/20153.19540.0049700mg/l
3/1/20151.93570.0041100mg/l
4/1/20153.20410.0037800mg/l
5/1/20153.02450.0037200mg/l
6/1/20154.43430.0033600mg/l
7/1/20155.85450.0036000mg/l
8/1/20155.36430.0039700mg/l
9/1/20156.10340.0046600mg/l
10/1/20155.13410.0049800mg/l
11/1/20157.77400.0057700mg/l
12/1/20158.98320.0065300mg/l
1/1/20166.84340.0067000mg/l
2/1/20163.97410.0064700mg/l
3/1/20163.32340.0060000mg/l
4/1/20164.28420.0058600mg/l
5/1/20162.96440.0050600mg/l
6/1/20167.95370.0048900mg/l
7/1/20166.95340.0049100mg/l
8/1/20163.92320.0049000mg/l
9/1/20169.92170.0060000mg/l
10/1/201610.69160.0070700mg/l
11/1/20166.72170.0076900mg/l
12/1/201611.64160.0083100mg/l
1/1/20173.39170.0077100mg/l
2/1/20172.45160.0074700mg/l
3/1/20172.09260.0061600mg/l
4/1/20173.04230.0048900mg/l
5/1/20174.46230.0045100mg/l
6/1/20177.99200.0039000mg/l
7/1/20175.61220.0042700mg/l
8/1/20176.54200.0049600mg/l
9/1/201712.55220.0067000mg/l
10/1/20179.44200.0077700mg/l
11/1/20175.69230.0079700mg/l
12/1/20174.49200.0073900mg/l
Loading Chart...
Target
0.0052 mg/l
Threshold
0.0061 mg/l
Excellent

Nitrogen, Total

Score: Excellent How was this determined?
Units: mg/l Year
2017
Historical
period of record
High 0.986 1.87
Mean 0.3666 0.34 0.17519962 0.5100000000
Low 0.066 0.03
No. of Samples 251 5,144

Five-year Trend Graph

     
1/1/2013350.52290.3632400mg/l
2/1/2013271.73260.3429500mg/l
3/1/2013256.43210.3227900mg/l
4/1/2013367.07290.3130000mg/l
5/1/2013424.42260.3202800mg/l
6/1/2013415.40250.3476000mg/l
7/1/2013394.60250.3549400mg/l
8/1/2013487.40250.3908900mg/l
9/1/2013522.14210.4351700mg/l
10/1/2013411.17300.4425200mg/l
11/1/2013505.19210.4559800mg/l
12/1/2013343.83300.4440600mg/l
1/1/2014366.90210.4394400mg/l
2/1/2014415.17300.4274000mg/l
3/1/2014382.20250.4040800mg/l
4/1/2014321.96250.3892100mg/l
5/1/2014370.71210.3668000mg/l
6/1/2014456.17300.3855200mg/l
7/1/2014422.20250.3947400mg/l
8/1/2014509.29210.4104200mg/l
9/1/2014557.86210.4397000mg/l
10/1/2014421.32340.4562600mg/l
11/1/2014439.50260.4677200mg/l
12/1/2014461.92260.4686800mg/l
1/1/2015397.96270.4646400mg/l
2/1/2015354.09220.4387800mg/l
3/1/2015385.75320.4100900mg/l
4/1/2015314.05210.3922100mg/l
5/1/2015395.74270.3849200mg/l
6/1/2015420.92260.3780900mg/l
7/1/2015464.04270.3891000mg/l
8/1/2015425.77260.4010500mg/l
9/1/2015362.06170.3971000mg/l
10/1/2015364.54240.4055100mg/l
11/1/2015432.35170.4116100mg/l
12/1/2015447.50160.4160400mg/l
1/1/2016385.76170.4030000mg/l
2/1/2016452.13240.4073900mg/l
3/1/2016297.94170.3967000mg/l
4/1/2016449.56250.4108700mg/l
5/1/2016336.31260.3948700mg/l
6/1/2016408.25200.3883300mg/l
7/1/2016367.35170.3852600mg/l
8/1/2016333.13160.3654200mg/l
9/1/2016347.35170.3736600mg/l
10/1/2016423.94160.3693900mg/l
11/1/2016350.59170.3717700mg/l
12/1/2016393.25160.3692700mg/l
1/1/2017291.06170.3565500mg/l
2/1/2017347.50160.3589500mg/l
3/1/2017509.58260.3859900mg/l
4/1/2017264.54240.3594200mg/l
5/1/2017392.32220.3663800mg/l
6/1/2017442.80200.3746300mg/l
7/1/2017427.64220.3974000mg/l
8/1/2017409.95200.4078100mg/l
9/1/2017447.41220.3974400mg/l
10/1/2017402.55200.4204500mg/l
11/1/2017364.64220.4158300mg/l
12/1/2017325.35200.3962600mg/l
Loading Chart...
Target
0.51 mg/l
Threshold
0.822 mg/l
Targets and thresholds shown on this graph are advisory approximations computed by Sarasota County using recent data. Regulatory thresholds have not been established. Learn more about Sarasota Bay Nitrogen targets/thresholds »
Excellent

Phosphorus, Total

Score: Excellent How was this determined?
Units: mg/l Year
2017
Historical
period of record
High 0.99 4.40
Mean 0.0598 0.0832 0.13316878 0.1500000000
Low 0.019 0.002
No. of Samples 253 5,286

Five-year Trend Graph

     
1/1/201351.66290.0708600mg/l
2/1/201351.54260.0685300mg/l
3/1/201374.76210.0638600mg/l
4/1/201394.58310.0656300mg/l
5/1/201351.92260.0647900mg/l
6/1/201356.96250.0635700mg/l
7/1/201358.96250.0647900mg/l
8/1/201355.12250.0653800mg/l
9/1/201359.05210.0627700mg/l
10/1/201353.47300.0559100mg/l
11/1/201352.86210.0560700mg/l
12/1/2013110.93300.0650700mg/l
1/1/201453.33210.0641300mg/l
2/1/201452.13300.0636300mg/l
3/1/201452.85260.0626000mg/l
4/1/201454.16250.0627100mg/l
5/1/201462.38210.0643000mg/l
6/1/201460.80300.0559400mg/l
7/1/201474.96250.0595500mg/l
8/1/201460.95210.0610200mg/l
9/1/201464.76210.0630000mg/l
10/1/201467.00340.0651400mg/l
11/1/201460.00260.0647500mg/l
12/1/201450.92260.0631000mg/l
1/1/201583.93280.0645900mg/l
2/1/201580.91220.0679200mg/l
3/1/201598.75320.0735900mg/l
4/1/201577.20250.0752900mg/l
5/1/201573.93280.0776100mg/l
6/1/201547.31260.0770100mg/l
7/1/201557.04270.0725200mg/l
8/1/201554.23260.0680800mg/l
9/1/201554.12170.0606400mg/l
10/1/2015327.60250.1023700mg/l
11/1/201572.73220.1021700mg/l
12/1/201578.75160.1074100mg/l
1/1/201678.24170.1109500mg/l
2/1/201687.60250.1165100mg/l
3/1/201656.47170.1169000mg/l
4/1/201670.40250.0740300mg/l
5/1/201648.46260.0699900mg/l
6/1/201653.81210.0658300mg/l
7/1/201666.47170.0638700mg/l
8/1/201660.00160.0592700mg/l
9/1/201664.12170.0605400mg/l
10/1/201693.75160.0644400mg/l
11/1/201680.56180.0697900mg/l
12/1/201668.75160.0722800mg/l
1/1/201755.29170.0704100mg/l
2/1/201767.50160.0716600mg/l
3/1/2017133.08260.0831600mg/l
4/1/2017350.42240.1259300mg/l
5/1/201750.26230.1208800mg/l
6/1/201744.80200.1168900mg/l
7/1/201751.59220.1162800mg/l
8/1/201751.75200.1136500mg/l
9/1/201758.86220.1012800mg/l
10/1/201757.75200.0525000mg/l
11/1/201751.26230.0526700mg/l
12/1/201751.55200.0537900mg/l
Loading Chart...
Target
0.15 mg/l
Threshold
0.19 mg/l

Dissolved Oxygen

Units: mg/l Year
2017
Historical
period of record
High 10.30 13.80
Mean 6.71 6.7 1.4609
Low 5.01 0.10
No. of Samples 234 16,787

Five-year Trend Graph

     
1/1/20137.30286.5200000mg/l
2/1/20137.96256.8700000mg/l
3/1/20136.65516.9600000mg/l
4/1/20137.46287.2000000mg/l
5/1/20136.36257.1300000mg/l
6/1/20135.45746.8600000mg/l
7/1/20136.00246.6500000mg/l
8/1/20135.76246.2800000mg/l
9/1/20136.09206.1900000mg/l
10/1/20136.74346.0700000mg/l
11/1/20136.59216.1100000mg/l
12/1/20137.55296.4600000mg/l
1/1/20147.06206.6300000mg/l
2/1/20147.91296.9900000mg/l
3/1/20147.32247.2000000mg/l
4/1/20147.21457.2700000mg/l
5/1/20147.73507.4600000mg/l
6/1/20146.33297.2600000mg/l
7/1/20145.70247.0300000mg/l
8/1/20144.55206.4700000mg/l
9/1/20145.00546.0900000mg/l
10/1/20146.58335.9800000mg/l
11/1/20147.31255.9100000mg/l
12/1/20144.11505.5400000mg/l
1/1/20153.99515.2600000mg/l
2/1/20152.56704.9300000mg/l
3/1/20157.91305.4100000mg/l
4/1/20157.40535.5500000mg/l
5/1/20158.29795.7100000mg/l
6/1/20156.40256.0900000mg/l
7/1/20155.79256.3900000mg/l
8/1/20156.84257.1100000mg/l
9/1/20155.91156.7700000mg/l
10/1/20156.50236.6200000mg/l
11/1/20156.97216.4000000mg/l
12/1/20157.26676.5500000mg/l
1/1/20169.84497.2200000mg/l
2/1/20168.01247.4200000mg/l
3/1/20167.30157.6500000mg/l
4/1/20168.971008.0600000mg/l
5/1/20166.92248.0500000mg/l
6/1/20166.89897.9900000mg/l
7/1/20166.17157.3800000mg/l
8/1/20165.92157.0300000mg/l
9/1/20167.01156.9800000mg/l
10/1/20165.28156.3700000mg/l
11/1/20166.34156.2700000mg/l
12/1/20166.45156.2000000mg/l
1/1/20177.61156.4400000mg/l
2/1/20177.00156.6200000mg/l
3/1/20177.38246.6800000mg/l
4/1/20177.08236.9800000mg/l
5/1/20176.45207.0000000mg/l
6/1/20176.35196.9800000mg/l
7/1/20176.32206.7600000mg/l
8/1/20175.94196.5900000mg/l
9/1/20176.43206.4300000mg/l
10/1/20176.63196.3500000mg/l
11/1/20176.48216.3600000mg/l
12/1/20176.96196.4600000mg/l
Loading Chart...
Target
mg/l
Threshold
0.00 mg/l

Light Attenuation

Units: K(1/m) Year
2017
Historical
period of record
High 2.9199 5.68
Mean 0.7 0.69 0.32659
Low 0.16 0.04
No. of Samples 220 4,224

Five-year Trend Graph

     
1/1/20130.67200.7600000K(1/m)
2/1/20130.69260.7700000K(1/m)
3/1/20130.68200.7400000K(1/m)
4/1/20130.45200.6900000K(1/m)
5/1/20130.61200.6700000K(1/m)
6/1/20130.69250.6300000K(1/m)
7/1/20130.64240.6300000K(1/m)
8/1/20130.57240.6100000K(1/m)
9/1/20130.82200.6300000K(1/m)
10/1/20130.76290.6800000K(1/m)
11/1/20130.67200.6900000K(1/m)
12/1/20130.62280.6800000K(1/m)
1/1/20140.54200.6600000K(1/m)
2/1/20140.70300.6900000K(1/m)
3/1/20140.52240.6400000K(1/m)
4/1/20140.72200.6300000K(1/m)
5/1/20140.49200.6000000K(1/m)
6/1/20140.65290.6000000K(1/m)
7/1/20140.58200.6100000K(1/m)
8/1/20140.56200.5900000K(1/m)
9/1/20140.60200.6000000K(1/m)
10/1/20140.68340.5900000K(1/m)
11/1/20140.87250.6600000K(1/m)
12/1/20140.91200.7000000K(1/m)
1/1/20150.75200.7300000K(1/m)
2/1/20150.95200.7900000K(1/m)
3/1/20150.64200.8000000K(1/m)
4/1/20150.67240.8000000K(1/m)
5/1/20150.44260.7300000K(1/m)
6/1/20150.59250.6700000K(1/m)
7/1/20150.81250.6800000K(1/m)
8/1/20150.77260.6500000K(1/m)
9/1/20150.60150.6500000K(1/m)
10/1/20150.68240.6500000K(1/m)
11/1/20150.78210.7100000K(1/m)
12/1/20150.67150.7200000K(1/m)
1/1/20160.69150.7000000K(1/m)
2/1/20160.88240.7200000K(1/m)
3/1/20160.74150.7400000K(1/m)
4/1/20161.00250.7900000K(1/m)
5/1/20160.59250.7600000K(1/m)
6/1/20160.77200.7800000K(1/m)
7/1/20160.56150.7600000K(1/m)
8/1/20160.64150.7200000K(1/m)
9/1/20161.67150.8700000K(1/m)
10/1/20160.87150.8500000K(1/m)
11/1/20160.63150.8600000K(1/m)
12/1/20160.77150.8600000K(1/m)
1/1/20170.65150.8700000K(1/m)
2/1/20170.70150.8800000K(1/m)
3/1/20170.70240.7200000K(1/m)
4/1/20170.71230.6900000K(1/m)
5/1/20170.68210.7000000K(1/m)
6/1/20170.63190.6800000K(1/m)
7/1/20170.73200.6900000K(1/m)
8/1/20170.79190.7100000K(1/m)
9/1/20170.82150.7300000K(1/m)
10/1/20170.71190.7300000K(1/m)
11/1/20170.73150.7400000K(1/m)
12/1/20170.50150.7100000K(1/m)
Loading Chart...
Target
K(1/m)
Threshold
0.00 K(1/m)

Rainfall

Units: inches/yr Year
2017
Historical
period of record
High 45.28 56.04
Mean 37.09 13.8396664217989
Low 8.12
No. of Samples 365 5,190

Five-year Trend Graph

     
1/1/20130.13310.1300000inches
2/1/20131.10231.1000000inches
3/1/20131.38311.3800000inches
4/1/20133.42303.4200000inches
5/1/20133.31313.3100000inches
6/1/201312.213012.2100000inches
7/1/20138.36318.3600000inches
8/1/201312.313112.3100000inches
9/1/201311.613011.6100000inches
10/1/20131.19311.1900000inches
11/1/20130.85300.8500000inches
12/1/20130.17310.1700000inches
1/1/20142.20312.2000000inches
2/1/20143.14283.1400000inches
3/1/20145.04315.0400000inches
4/1/20141.48291.4800000inches
5/1/20146.43316.4300000inches
6/1/20143.64303.6400000inches
7/1/20144.83314.8300000inches
8/1/20141.73281.7300000inches
9/1/20147.33257.3300000inches
10/1/20142.34292.3400000inches
11/1/20143.76303.7600000inches
12/1/20140.38310.3800000inches
1/1/20151.26311.2600000inches
2/1/20153.59283.5900000inches
3/1/20151.13311.1300000inches
4/1/20151.14301.1400000inches
5/1/20153.68313.6800000inches
6/1/20155.92305.9200000inches
7/1/201510.803110.8000000inches
8/1/20156.46316.4600000inches
9/1/20157.54307.5400000inches
10/1/20153.25313.2500000inches
11/1/20150.73300.7300000inches
12/1/20152.12312.1200000inches
1/1/20165.73315.7300000inches
2/1/20161.92291.9200000inches
3/1/20162.51312.5100000inches
4/1/20160.46300.4600000inches
5/1/20164.97314.9700000inches
6/1/20167.23307.2300000inches
7/1/20163.77313.7700000inches
8/1/201610.663110.6600000inches
9/1/20164.03304.0300000inches
10/1/20162.33312.3300000inches
11/1/20160.04300.0400000inches
12/1/20160.33310.3300000inches
1/1/20171.30311.3000000inches
2/1/20170.89280.8900000inches
3/1/20171.07311.0700000inches
4/1/20170.09300.0900000inches
5/1/20172.95312.9500000inches
6/1/20179.04309.0400000inches
7/1/20177.29317.2900000inches
8/1/201711.013111.0100000inches
9/1/20175.96305.9600000inches
10/1/20174.67314.6700000inches
11/1/20170.26300.2600000inches
12/1/20170.75310.7500000inches
Loading Chart...
Target
inches/yr
Threshold
inches/yr

Salinity

Units: PSS Year
2017
Historical
period of record
High 38.90 68.20
Mean 33.62 33.27 2.38792
Low 25.45 3.60
No. of Samples 235 18,297

Five-year Trend Graph

     
1/1/201333.592833.9500000PSS
2/1/201334.802534.0900000PSS
3/1/201334.842034.2300000PSS
4/1/201330.692833.6300000PSS
5/1/201335.162533.9000000PSS
6/1/201335.507334.1000000PSS
7/1/201332.052433.8400000PSS
8/1/201332.382433.4400000PSS
9/1/201330.402032.7000000PSS
10/1/201333.614833.1800000PSS
11/1/201333.072032.8400000PSS
12/1/201333.222932.4600000PSS
1/1/201433.352032.6700000PSS
2/1/201432.992932.7700000PSS
3/1/201433.832433.3500000PSS
4/1/201433.182533.2700000PSS
5/1/201432.992033.2600000PSS
6/1/201435.042933.5600000PSS
7/1/201435.462533.9200000PSS
8/1/201435.672034.3600000PSS
9/1/201435.795434.6900000PSS
10/1/201432.583334.5900000PSS
11/1/201433.382534.6500000PSS
12/1/201432.465534.2200000PSS
1/1/201531.458833.5600000PSS
2/1/201533.466933.1900000PSS
3/1/201532.432932.6300000PSS
4/1/201534.295332.9100000PSS
5/1/201535.037833.1900000PSS
6/1/201535.042533.6200000PSS
7/1/201535.592534.3100000PSS
8/1/201531.942534.0500000PSS
9/1/201531.541533.9100000PSS
10/1/201534.012433.8600000PSS
11/1/201533.992033.6900000PSS
12/1/201533.866533.4900000PSS
1/1/201633.995033.2200000PSS
2/1/201632.382433.3000000PSS
3/1/201633.011533.5400000PSS
4/1/201634.209633.5700000PSS
5/1/201634.692533.6900000PSS
6/1/201635.298433.9300000PSS
7/1/201634.721534.0500000PSS
8/1/201634.661534.4300000PSS
9/1/201629.721533.8800000PSS
10/1/201628.171532.8800000PSS
11/1/201633.561532.6900000PSS
12/1/201633.381532.3700000PSS
1/1/201733.291532.1300000PSS
2/1/201734.971532.1800000PSS
3/1/201734.842433.0400000PSS
4/1/201735.432334.2500000PSS
5/1/201736.142134.6800000PSS
6/1/201733.641934.7200000PSS
7/1/201733.822034.8100000PSS
8/1/201732.741934.4400000PSS
9/1/201729.062033.4700000PSS
10/1/201732.161932.9300000PSS
11/1/201733.122132.4200000PSS
12/1/201733.701932.4300000PSS
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Turbidity

Units: NTU Year
2017
Historical
period of record
High 10.00 39.00
Mean 2.63 2.64 2.43468
Low 0.60 0.03
No. of Samples 252 14,871

Five-year Trend Graph

     
1/1/20133.50292.9200000NTU
2/1/20133.16273.0800000NTU
3/1/20135.23213.3700000NTU
4/1/20132.57303.2400000NTU
5/1/20133.20263.4500000NTU
6/1/20132.63253.3800000NTU
7/1/20132.06253.1400000NTU
8/1/20131.95252.9400000NTU
9/1/20132.30212.4500000NTU
10/1/20131.91302.3400000NTU
11/1/20133.28212.3600000NTU
12/1/20132.15302.2800000NTU
1/1/20143.33212.4900000NTU
2/1/20141.40312.4000000NTU
3/1/20141.89262.3300000NTU
4/1/20144.31262.7300000NTU
5/1/20142.50212.6000000NTU
6/1/20141.95302.5600000NTU
7/1/20142.19252.3700000NTU
8/1/20142.62212.5800000NTU
9/1/20142.99212.7600000NTU
10/1/20142.19342.4100000NTU
11/1/20141.91262.3100000NTU
12/1/20144.03262.6600000NTU
1/1/20153.02282.7900000NTU
2/1/20156.85223.5000000NTU
3/1/20152.44333.4100000NTU
4/1/20152.70253.4900000NTU
5/1/20152.26283.5500000NTU
6/1/20152.27273.2600000NTU
7/1/20152.80283.2200000NTU
8/1/20152.00272.4100000NTU
9/1/20152.07172.3500000NTU
10/1/20151.84252.2100000NTU
11/1/20152.28222.2100000NTU
12/1/20152.04162.1700000NTU
1/1/20162.58172.1400000NTU
2/1/20164.66252.5800000NTU
3/1/20165.36173.1300000NTU
4/1/20165.60263.7500000NTU
5/1/20162.16273.7300000NTU
6/1/20163.76214.0200000NTU
7/1/20162.66174.0300000NTU
8/1/20162.24163.6300000NTU
9/1/20161.89173.0500000NTU
10/1/20161.94162.4400000NTU
11/1/20161.98182.4100000NTU
12/1/20161.79162.0800000NTU
1/1/20172.50172.0600000NTU
2/1/20173.61162.2900000NTU
3/1/20172.18262.3300000NTU
4/1/20172.95242.5000000NTU
5/1/20173.07232.6800000NTU
6/1/20173.13202.9100000NTU
7/1/20171.87222.8000000NTU
8/1/20172.82202.6700000NTU
9/1/20172.46222.7200000NTU
10/1/20172.55202.6500000NTU
11/1/20172.35222.5300000NTU
12/1/20172.38202.4100000NTU
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Other Measures of Bay Health

In addition to nutrient levels and chlorophyll concentration, dissolved oxygen levels, and water clarity are also objective indicators of bay health. These have complex interactive cycles which are affected by rainfall, temperature, and tidal action, as well as other factors. High nutrient levels (nitrogen and phosphorus) can stimulate excessive growth of marine algae (indicated by chlorophyll a level), resulting in reduced water clarity (and increased light attenuation) and depleted oxygen levels. Both plants and animals in a bay need oxygen to survive, and the seagrasses which provide food and cover for bay creatures need light for photosynthesis.

Bay Contour Maps (2017)

Contour mapping is one of the best ways to visualize spatial differences in coastal water quality. The interactive map shown below presents monthly data for one selected water quality indicator atop an aerial view of the bay. Choose a different water quality parameter from the list at the top to change the map. Learn More about Water Quality Contour Mapping »

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Contour Visibility:

Visit the Water Quality Contour Mapping Tool to view and compare monthly water quality contour maps for ten different water quality indicators. In addition, you can generate your own custom maps.

Contour Legend:

  • Less than 1 mg/l
  • 1.0 - 5.9 mg/l
  • 6.0 - 10.9 mg/l
  • 11.0 - 17.9 mg/l
  • Greater than 18 mg/l

Seagrasses

Among the most important habitats in Florida's estuarine environments, seagrass beds are indispensable for the role they play in cycling nutrients, supplying food for wildlife, stabilizing sediments, and providing habitat for juvenile and adult finfish and shellfish. Use the interactive map below to observe the size, density and location of seagrass beds from year to year. The graph shows how the total amount of seagrass in the bay has changed over time. Learn More about Seagrasses »

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Target
2,022 acres

Land Use / Land Cover

Land use within a bay'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 (upland or wetland, e.g.), 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 »

Sarasota Bay is located within the Sarasota Bay Watershed. The chart below shows the land use / land cover characteristics for Sarasota Bay Watershed within the boundary of this Water Atlas. View details about the Sarasota Bay Watershed »

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