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.
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.
Caution
Chlorophyll a
Units: mg/l |
Year 2015 |
Historical period of record |
High |
0.0478 |
0.0612 |
Mean |
0.0072 |
0.0052
0.00576031
0.0043000000
|
Low |
0.0013 |
0.0001 |
No. of Samples |
50 |
641 |
Target |
0.0043 |
0.0043 |
Threshold |
0.0049 |
0.0049 |
MDL |
0.0005 |
0.0005 |
GeoMean |
0.0054 |
0.0054 |
Five-year Trend Graph
| | | | |
---|
1/1/2011 | 3.01 | 4 | 0.0030100 | mg/l |
2/1/2011 | 4.88 | 4 | 0.0039500 | mg/l |
3/1/2011 | 1.82 | 4 | 0.0032400 | mg/l |
4/1/2011 | 5.08 | 4 | 0.0037000 | mg/l |
5/1/2011 | 4.99 | 4 | 0.0039600 | mg/l |
6/1/2011 | 5.98 | 4 | 0.0042900 | mg/l |
7/1/2011 | 7.18 | 4 | 0.0049900 | mg/l |
8/1/2011 | 7.97 | 4 | 0.0055000 | mg/l |
9/1/2011 | 7.80 | 4 | 0.0065000 | mg/l |
10/1/2011 | 8.39 | 4 | 0.0070500 | mg/l |
11/1/2011 | 3.56 | 4 | 0.0068100 | mg/l |
12/1/2011 | 1.88 | 4 | 0.0061300 | mg/l |
1/1/2012 | 2.03 | 4 | 0.0052700 | mg/l |
2/1/2012 | 2.03 | 4 | 0.0042800 | mg/l |
3/1/2012 | 2.04 | 4 | 0.0033200 | mg/l |
4/1/2012 | 1.18 | 4 | 0.0021200 | mg/l |
5/1/2012 | 3.12 | 4 | 0.0020500 | mg/l |
6/1/2012 | 5.49 | 4 | 0.0026500 | mg/l |
7/1/2012 | 7.39 | 4 | 0.0035400 | mg/l |
8/1/2012 | 8.51 | 4 | 0.0046200 | mg/l |
9/1/2012 | 5.22 | 5 | 0.0051500 | mg/l |
10/1/2012 | 5.10 | 4 | 0.0058100 | mg/l |
11/1/2012 | 4.11 | 5 | 0.0059700 | mg/l |
12/1/2012 | 1.83 | 4 | 0.0053600 | mg/l |
1/1/2013 | 6.04 | 4 | 0.0051400 | mg/l |
2/1/2013 | 1.82 | 4 | 0.0040200 | mg/l |
3/1/2013 | 2.34 | 4 | 0.0035400 | mg/l |
4/1/2013 | 1.98 | 4 | 0.0030200 | mg/l |
5/1/2013 | 2.59 | 4 | 0.0027700 | mg/l |
6/1/2013 | 10.65 | 4 | 0.0042400 | mg/l |
7/1/2013 | 11.09 | 4 | 0.0050800 | mg/l |
8/1/2013 | 8.63 | 4 | 0.0062100 | mg/l |
9/1/2013 | 6.91 | 4 | 0.0069800 | mg/l |
10/1/2013 | 18.98 | 4 | 0.0098100 | mg/l |
11/1/2013 | 3.95 | 4 | 0.0100400 | mg/l |
12/1/2013 | 4.04 | 4 | 0.0089300 | mg/l |
1/1/2014 | 3.19 | 4 | 0.0076200 | mg/l |
2/1/2014 | 2.08 | 4 | 0.0065300 | mg/l |
3/1/2014 | 2.16 | 4 | 0.0057300 | mg/l |
4/1/2014 | 2.33 | 4 | 0.0029600 | mg/l |
5/1/2014 | 5.31 | 4 | 0.0031900 | mg/l |
6/1/2014 | 7.41 | 4 | 0.0037500 | mg/l |
7/1/2014 | 6.99 | 4 | 0.0043800 | mg/l |
8/1/2014 | 4.51 | 4 | 0.0047900 | mg/l |
9/1/2014 | 5.67 | 4 | 0.0053700 | mg/l |
10/1/2014 | 15.31 | 4 | 0.0075300 | mg/l |
11/1/2014 | 4.61 | 4 | 0.0074200 | mg/l |
12/1/2014 | 5.72 | 4 | 0.0071400 | mg/l |
1/1/2015 | 3.53 | 5 | 0.0065600 | mg/l |
2/1/2015 | 3.44 | 4 | 0.0063800 | mg/l |
3/1/2015 | 2.78 | 4 | 0.0059000 | mg/l |
4/1/2015 | 2.23 | 4 | 0.0037200 | mg/l |
5/1/2015 | 2.95 | 4 | 0.0034400 | mg/l |
6/1/2015 | 8.76 | 4 | 0.0039500 | mg/l |
7/1/2015 | 6.05 | 4 | 0.0043700 | mg/l |
8/1/2015 | 12.25 | 4 | 0.0058400 | mg/l |
9/1/2015 | 12.77 | 4 | 0.0075000 | mg/l |
10/1/2015 | 17.05 | 4 | 0.0099700 | mg/l |
11/1/2015 | 9.79 | 5 | 0.0111100 | mg/l |
12/1/2015 | 5.26 | 4 | 0.0105300 | mg/l |
Caution
Nitrogen, Total
Units: mg/l |
Year 2015 |
Historical period of record |
High |
1.621 |
1.715 |
Mean |
0.5511 |
0.439
0.27315048
0.4000000000
|
Low |
0.145 |
0.055 |
No. of Samples |
50 |
637 |
Target |
0.40 |
0.40 |
Threshold |
0.42 |
0.42 |
MDL |
|
|
GeoMean |
0.4726 |
0.4726 |
Five-year Trend Graph
| | | | |
---|
1/1/2011 | 268.00 | 4 | 0.2680000 | mg/l |
2/1/2011 | 319.50 | 4 | 0.2937500 | mg/l |
3/1/2011 | 387.75 | 4 | 0.3250800 | mg/l |
4/1/2011 | 444.25 | 4 | 0.3548800 | mg/l |
5/1/2011 | 422.50 | 4 | 0.3684000 | mg/l |
6/1/2011 | 373.25 | 4 | 0.3692100 | mg/l |
7/1/2011 | 426.25 | 4 | 0.3955800 | mg/l |
8/1/2011 | 647.50 | 4 | 0.4502500 | mg/l |
9/1/2011 | 848.50 | 4 | 0.5270400 | mg/l |
10/1/2011 | 445.50 | 4 | 0.5272500 | mg/l |
11/1/2011 | 358.75 | 4 | 0.5166300 | mg/l |
12/1/2011 | 298.75 | 4 | 0.5042100 | mg/l |
1/1/2012 | 275.50 | 4 | 0.4790800 | mg/l |
2/1/2012 | 349.00 | 4 | 0.4293300 | mg/l |
3/1/2012 | 337.50 | 4 | 0.3441700 | mg/l |
4/1/2012 | 270.00 | 4 | 0.3149200 | mg/l |
5/1/2012 | 260.00 | 4 | 0.2984600 | mg/l |
6/1/2012 | 267.50 | 4 | 0.2932500 | mg/l |
7/1/2012 | 809.00 | 4 | 0.3821700 | mg/l |
8/1/2012 | 543.00 | 4 | 0.4145000 | mg/l |
9/1/2012 | 727.40 | 5 | 0.4794800 | mg/l |
10/1/2012 | 503.00 | 4 | 0.5183200 | mg/l |
11/1/2012 | 494.60 | 5 | 0.5574200 | mg/l |
12/1/2012 | 240.00 | 4 | 0.5528300 | mg/l |
1/1/2013 | 351.50 | 4 | 0.4765800 | mg/l |
2/1/2013 | 258.00 | 4 | 0.4290800 | mg/l |
3/1/2013 | 175.00 | 4 | 0.3370200 | mg/l |
4/1/2013 | 275.25 | 4 | 0.2990600 | mg/l |
5/1/2013 | 397.50 | 4 | 0.2828800 | mg/l |
6/1/2013 | 615.25 | 4 | 0.3454200 | mg/l |
7/1/2013 | 1016.25 | 4 | 0.4562100 | mg/l |
8/1/2013 | 850.25 | 4 | 0.5549200 | mg/l |
9/1/2013 | 770.75 | 4 | 0.6542100 | mg/l |
10/1/2013 | 987.50 | 4 | 0.7729200 | mg/l |
11/1/2013 | 418.25 | 4 | 0.7763800 | mg/l |
12/1/2013 | 401.00 | 4 | 0.7406700 | mg/l |
1/1/2014 | 353.50 | 4 | 0.6302100 | mg/l |
2/1/2014 | 396.25 | 4 | 0.5545400 | mg/l |
3/1/2014 | 365.25 | 4 | 0.4869600 | mg/l |
4/1/2014 | 420.25 | 4 | 0.3924200 | mg/l |
5/1/2014 | 425.25 | 4 | 0.3935800 | mg/l |
6/1/2014 | 530.00 | 4 | 0.4150800 | mg/l |
7/1/2014 | 470.75 | 4 | 0.4346300 | mg/l |
8/1/2014 | 758.00 | 4 | 0.4949200 | mg/l |
9/1/2014 | 614.25 | 4 | 0.5364200 | mg/l |
10/1/2014 | 1019.50 | 4 | 0.6362900 | mg/l |
11/1/2014 | 462.75 | 4 | 0.6425400 | mg/l |
12/1/2014 | 473.50 | 4 | 0.6331300 | mg/l |
1/1/2015 | 504.00 | 5 | 0.6386700 | mg/l |
2/1/2015 | 315.50 | 4 | 0.5649200 | mg/l |
3/1/2015 | 340.00 | 4 | 0.5192100 | mg/l |
4/1/2015 | 180.00 | 4 | 0.3792900 | mg/l |
5/1/2015 | 372.75 | 4 | 0.3642900 | mg/l |
6/1/2015 | 535.00 | 4 | 0.3745400 | mg/l |
7/1/2015 | 414.00 | 4 | 0.3595400 | mg/l |
8/1/2015 | 995.25 | 4 | 0.4728300 | mg/l |
9/1/2015 | 950.75 | 4 | 0.5746300 | mg/l |
10/1/2015 | 797.00 | 4 | 0.6774600 | mg/l |
11/1/2015 | 814.60 | 5 | 0.7511000 | mg/l |
12/1/2015 | 339.75 | 4 | 0.7185600 | mg/l |
Excellent
Phosphorus, Total
Units: mg/l |
Year 2015 |
Historical period of record |
High |
0.32 |
0.47 |
Mean |
0.1072 |
0.124
0.07265045
0.1700000000
|
Low |
0.05 |
0.05 |
No. of Samples |
50 |
641 |
Target |
0.17 |
0.17 |
Threshold |
0.18 |
0.18 |
MDL |
0.0001 |
0.0001 |
GeoMean |
0.0925 |
0.0925 |
Five-year Trend Graph
| | | | |
---|
1/1/2011 | 50.00 | 4 | 0.0500000 | mg/l |
2/1/2011 | 50.00 | 4 | 0.0500000 | mg/l |
3/1/2011 | 52.50 | 4 | 0.0508300 | mg/l |
4/1/2011 | 70.00 | 4 | 0.0556300 | mg/l |
5/1/2011 | 85.00 | 4 | 0.0615000 | mg/l |
6/1/2011 | 77.50 | 4 | 0.0641700 | mg/l |
7/1/2011 | 107.50 | 4 | 0.0737500 | mg/l |
8/1/2011 | 145.00 | 4 | 0.0895800 | mg/l |
9/1/2011 | 170.00 | 4 | 0.1091700 | mg/l |
10/1/2011 | 65.00 | 4 | 0.1083300 | mg/l |
11/1/2011 | 50.00 | 4 | 0.1025000 | mg/l |
12/1/2011 | 52.50 | 4 | 0.0983300 | mg/l |
1/1/2012 | 50.00 | 4 | 0.0887500 | mg/l |
2/1/2012 | 60.00 | 4 | 0.0745800 | mg/l |
3/1/2012 | 55.00 | 4 | 0.0554200 | mg/l |
4/1/2012 | 50.00 | 4 | 0.0529200 | mg/l |
5/1/2012 | 65.00 | 4 | 0.0554200 | mg/l |
6/1/2012 | 60.00 | 4 | 0.0566700 | mg/l |
7/1/2012 | 242.50 | 4 | 0.0887500 | mg/l |
8/1/2012 | 112.50 | 4 | 0.0975000 | mg/l |
9/1/2012 | 126.00 | 5 | 0.1093300 | mg/l |
10/1/2012 | 87.50 | 4 | 0.1155800 | mg/l |
11/1/2012 | 96.00 | 5 | 0.1207500 | mg/l |
12/1/2012 | 50.00 | 4 | 0.1190800 | mg/l |
1/1/2013 | 57.50 | 4 | 0.0882500 | mg/l |
2/1/2013 | 50.00 | 4 | 0.0778300 | mg/l |
3/1/2013 | 65.00 | 4 | 0.0676700 | mg/l |
4/1/2013 | 55.00 | 4 | 0.0622500 | mg/l |
5/1/2013 | 50.00 | 4 | 0.0545800 | mg/l |
6/1/2013 | 125.00 | 4 | 0.0670800 | mg/l |
7/1/2013 | 237.50 | 4 | 0.0970800 | mg/l |
8/1/2013 | 160.00 | 4 | 0.1154200 | mg/l |
9/1/2013 | 97.50 | 4 | 0.1208300 | mg/l |
10/1/2013 | 195.00 | 4 | 0.1441700 | mg/l |
11/1/2013 | 70.00 | 4 | 0.1475000 | mg/l |
12/1/2013 | 52.50 | 4 | 0.1354200 | mg/l |
1/1/2014 | 57.50 | 4 | 0.1054200 | mg/l |
2/1/2014 | 65.00 | 4 | 0.0895800 | mg/l |
3/1/2014 | 57.50 | 4 | 0.0829200 | mg/l |
4/1/2014 | 87.50 | 4 | 0.0650000 | mg/l |
5/1/2014 | 85.00 | 4 | 0.0675000 | mg/l |
6/1/2014 | 115.00 | 4 | 0.0779200 | mg/l |
7/1/2014 | 130.00 | 4 | 0.0900000 | mg/l |
8/1/2014 | 137.50 | 4 | 0.1020800 | mg/l |
9/1/2014 | 75.00 | 4 | 0.1050000 | mg/l |
10/1/2014 | 170.00 | 4 | 0.1187500 | mg/l |
11/1/2014 | 85.00 | 4 | 0.1187500 | mg/l |
12/1/2014 | 50.00 | 4 | 0.1079200 | mg/l |
1/1/2015 | 78.00 | 5 | 0.0992500 | mg/l |
2/1/2015 | 75.00 | 4 | 0.0888300 | mg/l |
3/1/2015 | 50.00 | 4 | 0.0846700 | mg/l |
4/1/2015 | 80.00 | 4 | 0.0696700 | mg/l |
5/1/2015 | 65.00 | 4 | 0.0663300 | mg/l |
6/1/2015 | 107.50 | 4 | 0.0759200 | mg/l |
7/1/2015 | 100.00 | 4 | 0.0795800 | mg/l |
8/1/2015 | 195.00 | 4 | 0.0995800 | mg/l |
9/1/2015 | 165.00 | 4 | 0.1187500 | mg/l |
10/1/2015 | 170.00 | 4 | 0.1337500 | mg/l |
11/1/2015 | 148.00 | 5 | 0.1475800 | mg/l |
12/1/2015 | 50.00 | 4 | 0.1380000 | mg/l |
Dissolved Oxygen
Units: mg/l |
Year 2015 |
Historical period of record |
High |
8.90 |
9.20 |
Mean |
6.15 |
6.19
1.06221
|
Low |
3.40 |
2.10 |
No. of Samples |
48 |
608 |
Target |
|
|
Threshold |
0.00 |
0.00 |
MDL |
0.20 |
0.20 |
GeoMean |
6.0366 |
6.0366 |
Five-year Trend Graph
| | | | |
---|
1/1/2011 | 7.63 | 4 | 7.6300000 | mg/l |
2/1/2011 | 7.33 | 4 | 7.4800000 | mg/l |
3/1/2011 | 7.05 | 4 | 7.3400000 | mg/l |
4/1/2011 | 6.33 | 4 | 7.0900000 | mg/l |
5/1/2011 | 6.03 | 4 | 6.8700000 | mg/l |
6/1/2011 | 5.60 | 4 | 6.6600000 | mg/l |
7/1/2011 | 5.38 | 4 | 6.2900000 | mg/l |
8/1/2011 | 4.60 | 4 | 5.8300000 | mg/l |
9/1/2011 | 5.10 | 4 | 5.5100000 | mg/l |
10/1/2011 | 5.50 | 4 | 5.3700000 | mg/l |
11/1/2011 | 6.28 | 4 | 5.4100000 | mg/l |
12/1/2011 | 6.95 | 4 | 5.6400000 | mg/l |
1/1/2012 | 7.18 | 4 | 5.9400000 | mg/l |
2/1/2012 | 6.70 | 4 | 6.2900000 | mg/l |
3/1/2012 | 6.70 | 4 | 6.5500000 | mg/l |
4/1/2012 | 6.28 | 4 | 6.6800000 | mg/l |
5/1/2012 | 5.93 | 4 | 6.6200000 | mg/l |
6/1/2012 | 5.75 | 4 | 6.4200000 | mg/l |
7/1/2012 | 5.28 | 4 | 6.1100000 | mg/l |
8/1/2012 | 4.78 | 4 | 5.7900000 | mg/l |
9/1/2012 | 4.95 | 4 | 5.5000000 | mg/l |
10/1/2012 | 5.10 | 4 | 5.3000000 | mg/l |
11/1/2012 | 5.50 | 4 | 5.2300000 | mg/l |
12/1/2012 | 6.00 | 4 | 5.2700000 | mg/l |
1/1/2013 | 6.23 | 4 | 5.4300000 | mg/l |
2/1/2013 | 7.53 | 4 | 5.8900000 | mg/l |
3/1/2013 | 7.18 | 4 | 6.2600000 | mg/l |
4/1/2013 | 6.45 | 4 | 6.4800000 | mg/l |
5/1/2013 | 6.28 | 4 | 6.6100000 | mg/l |
6/1/2013 | 4.18 | 4 | 6.3100000 | mg/l |
7/1/2013 | 5.58 | 4 | 6.2000000 | mg/l |
8/1/2013 | 4.85 | 4 | 5.7500000 | mg/l |
9/1/2013 | 5.65 | 4 | 5.5000000 | mg/l |
10/1/2013 | 5.55 | 4 | 5.3500000 | mg/l |
11/1/2013 | 6.48 | 4 | 5.3800000 | mg/l |
12/1/2013 | 6.80 | 4 | 5.8200000 | mg/l |
1/1/2014 | 6.70 | 4 | 6.0100000 | mg/l |
2/1/2014 | 7.18 | 4 | 6.3900000 | mg/l |
3/1/2014 | 6.50 | 4 | 6.5400000 | mg/l |
4/1/2014 | 6.45 | 4 | 6.6900000 | mg/l |
5/1/2014 | 6.73 | 4 | 6.7300000 | mg/l |
6/1/2014 | 5.63 | 4 | 6.5300000 | mg/l |
7/1/2014 | 5.20 | 4 | 6.2800000 | mg/l |
8/1/2014 | 3.20 | 4 | 5.6200000 | mg/l |
9/1/2014 | 5.28 | 4 | 5.4200000 | mg/l |
10/1/2014 | 4.40 | 4 | 5.0700000 | mg/l |
11/1/2014 | 6.88 | 4 | 5.1000000 | mg/l |
12/1/2014 | 7.08 | 4 | 5.3400000 | mg/l |
1/1/2015 | 5.90 | 4 | 5.4600000 | mg/l |
2/1/2015 | 8.13 | 4 | 6.2800000 | mg/l |
3/1/2015 | 7.13 | 4 | 6.5900000 | mg/l |
4/1/2015 | 6.85 | 4 | 7.0000000 | mg/l |
5/1/2015 | 6.60 | 4 | 6.9500000 | mg/l |
6/1/2015 | 5.63 | 4 | 6.7100000 | mg/l |
7/1/2015 | 6.05 | 4 | 6.7300000 | mg/l |
8/1/2015 | 5.28 | 4 | 6.2600000 | mg/l |
9/1/2015 | 5.13 | 4 | 5.9200000 | mg/l |
10/1/2015 | 5.25 | 4 | 5.6600000 | mg/l |
11/1/2015 | 5.03 | 4 | 5.4000000 | mg/l |
12/1/2015 | 6.83 | 4 | 5.6000000 | mg/l |
Light Attenuation
Units: K(1/m) |
Year 2015 |
Historical period of record |
High |
6.05 |
9.04 |
Mean |
1.39 |
1.11
0.90132
|
Low |
0.43 |
0.06 |
No. of Samples |
48 |
600 |
Target |
|
|
Threshold |
0.00 |
0.00 |
MDL |
0.05 |
0.05 |
GeoMean |
1.1153 |
1.1153 |
Five-year Trend Graph
| | | | |
---|
1/1/2011 | 1.27 | 4 | 1.2700000 | K(1/m) |
2/1/2011 | 1.07 | 4 | 1.1700000 | K(1/m) |
3/1/2011 | 0.80 | 4 | 1.0500000 | K(1/m) |
4/1/2011 | 1.13 | 4 | 1.0700000 | K(1/m) |
5/1/2011 | 0.97 | 4 | 1.0500000 | K(1/m) |
6/1/2011 | 0.80 | 4 | 1.0100000 | K(1/m) |
7/1/2011 | 0.96 | 4 | 0.9600000 | K(1/m) |
8/1/2011 | 1.11 | 4 | 0.9600000 | K(1/m) |
9/1/2011 | 1.85 | 4 | 1.1400000 | K(1/m) |
10/1/2011 | 1.23 | 4 | 1.1500000 | K(1/m) |
11/1/2011 | 0.84 | 4 | 1.1300000 | K(1/m) |
12/1/2011 | 0.63 | 4 | 1.1000000 | K(1/m) |
1/1/2012 | 0.99 | 4 | 1.1100000 | K(1/m) |
2/1/2012 | 0.75 | 4 | 1.0500000 | K(1/m) |
3/1/2012 | 0.84 | 4 | 0.8800000 | K(1/m) |
4/1/2012 | 0.55 | 4 | 0.7700000 | K(1/m) |
5/1/2012 | 0.56 | 4 | 0.7200000 | K(1/m) |
6/1/2012 | 0.86 | 4 | 0.7600000 | K(1/m) |
7/1/2012 | 1.71 | 4 | 0.8800000 | K(1/m) |
8/1/2012 | 1.08 | 4 | 0.9300000 | K(1/m) |
9/1/2012 | 1.72 | 4 | 1.0800000 | K(1/m) |
10/1/2012 | 1.55 | 4 | 1.2500000 | K(1/m) |
11/1/2012 | 1.02 | 4 | 1.3200000 | K(1/m) |
12/1/2012 | 0.76 | 4 | 1.3100000 | K(1/m) |
1/1/2013 | 0.80 | 4 | 1.1600000 | K(1/m) |
2/1/2013 | 0.70 | 4 | 1.0900000 | K(1/m) |
3/1/2013 | 0.79 | 4 | 0.9400000 | K(1/m) |
4/1/2013 | 0.50 | 4 | 0.7600000 | K(1/m) |
5/1/2013 | 0.81 | 4 | 0.7300000 | K(1/m) |
6/1/2013 | 1.17 | 4 | 0.8000000 | K(1/m) |
7/1/2013 | 2.90 | 4 | 1.1500000 | K(1/m) |
8/1/2013 | 1.51 | 4 | 1.2800000 | K(1/m) |
9/1/2013 | 1.96 | 4 | 1.4800000 | K(1/m) |
10/1/2013 | 1.98 | 4 | 1.7200000 | K(1/m) |
11/1/2013 | 0.84 | 4 | 1.7300000 | K(1/m) |
12/1/2013 | 0.49 | 4 | 1.6100000 | K(1/m) |
1/1/2014 | 0.55 | 4 | 1.2200000 | K(1/m) |
2/1/2014 | 0.70 | 4 | 1.0900000 | K(1/m) |
3/1/2014 | 0.75 | 4 | 0.8900000 | K(1/m) |
4/1/2014 | 0.92 | 4 | 0.7100000 | K(1/m) |
5/1/2014 | 1.27 | 4 | 0.7800000 | K(1/m) |
6/1/2014 | 1.13 | 4 | 0.8900000 | K(1/m) |
7/1/2014 | 0.77 | 4 | 0.9200000 | K(1/m) |
8/1/2014 | 1.52 | 4 | 1.0600000 | K(1/m) |
9/1/2014 | 0.88 | 4 | 1.0800000 | K(1/m) |
10/1/2014 | 3.25 | 4 | 1.4700000 | K(1/m) |
11/1/2014 | 0.81 | 4 | 1.3900000 | K(1/m) |
12/1/2014 | 1.21 | 4 | 1.4100000 | K(1/m) |
1/1/2015 | 0.76 | 4 | 1.4100000 | K(1/m) |
2/1/2015 | 1.20 | 4 | 1.3500000 | K(1/m) |
3/1/2015 | 0.72 | 4 | 1.3300000 | K(1/m) |
4/1/2015 | 0.71 | 4 | 0.9000000 | K(1/m) |
5/1/2015 | 0.79 | 4 | 0.9000000 | K(1/m) |
6/1/2015 | 1.11 | 4 | 0.8800000 | K(1/m) |
7/1/2015 | 0.68 | 4 | 0.8700000 | K(1/m) |
8/1/2015 | 2.93 | 4 | 1.1600000 | K(1/m) |
9/1/2015 | 3.11 | 4 | 1.5600000 | K(1/m) |
10/1/2015 | 2.27 | 4 | 1.8200000 | K(1/m) |
11/1/2015 | 1.61 | 4 | 1.9500000 | K(1/m) |
12/1/2015 | 0.85 | 4 | 1.9100000 | K(1/m) |
Rainfall
Units: inches/yr |
Year 2015 |
Historical period of record |
High |
55.99 |
66.45 |
Mean |
|
42.0
17.5513127985453
|
Low |
|
5.43 |
No. of Samples |
365 |
5,043 |
Target |
|
|
Threshold |
|
|
MDL |
|
|
GeoMean |
|
|
Five-year Trend Graph
| | | | |
---|
1/1/2011 | 2.30 | 31 | 2.3000000 | inches |
2/1/2011 | 0.35 | 28 | 0.3500000 | inches |
3/1/2011 | 5.41 | 31 | 5.4100000 | inches |
4/1/2011 | 0.83 | 30 | 0.8300000 | inches |
5/1/2011 | 2.85 | 31 | 2.8500000 | inches |
6/1/2011 | 3.64 | 30 | 3.6400000 | inches |
7/1/2011 | 12.48 | 31 | 12.4800000 | inches |
8/1/2011 | 5.35 | 31 | 5.3500000 | inches |
9/1/2011 | 4.03 | 30 | 4.0300000 | inches |
10/1/2011 | 1.57 | 30 | 1.5700000 | inches |
11/1/2011 | 1.93 | 30 | 1.9300000 | inches |
12/1/2011 | 0.06 | 30 | 0.0600000 | inches |
1/1/2012 | 0.36 | 29 | 0.3600000 | inches |
2/1/2012 | 1.10 | 29 | 1.1000000 | inches |
3/1/2012 | 1.52 | 31 | 1.5200000 | inches |
4/1/2012 | 2.25 | 24 | 2.2500000 | inches |
5/1/2012 | 2.18 | 31 | 2.1800000 | inches |
6/1/2012 | 14.14 | 30 | 14.1400000 | inches |
7/1/2012 | 7.30 | 31 | 7.3000000 | inches |
8/1/2012 | 12.42 | 31 | 12.4200000 | inches |
9/1/2012 | 5.23 | 30 | 5.2300000 | inches |
10/1/2012 | 3.36 | 31 | 3.3600000 | inches |
11/1/2012 | 0.20 | 28 | 0.2000000 | inches |
12/1/2012 | 1.91 | 31 | 1.9100000 | inches |
1/1/2013 | 0.48 | 31 | 0.4800000 | inches |
2/1/2013 | 0.96 | 23 | 0.9600000 | inches |
3/1/2013 | 1.85 | 30 | 1.8500000 | inches |
4/1/2013 | 3.99 | 30 | 3.9900000 | inches |
5/1/2013 | 6.07 | 31 | 6.0700000 | inches |
6/1/2013 | 12.38 | 30 | 12.3800000 | inches |
7/1/2013 | 11.34 | 31 | 11.3400000 | inches |
8/1/2013 | 8.62 | 31 | 8.6200000 | inches |
9/1/2013 | 12.07 | 30 | 12.0700000 | inches |
10/1/2013 | 2.37 | 31 | 2.3700000 | inches |
11/1/2013 | 0.94 | 30 | 0.9400000 | inches |
12/1/2013 | 0.35 | 31 | 0.3500000 | inches |
1/1/2014 | 2.90 | 31 | 2.9000000 | inches |
2/1/2014 | 1.23 | 28 | 1.2300000 | inches |
3/1/2014 | 4.70 | 31 | 4.7000000 | inches |
4/1/2014 | 1.30 | 29 | 1.3000000 | inches |
5/1/2014 | 5.37 | 31 | 5.3700000 | inches |
6/1/2014 | 4.82 | 30 | 4.8200000 | inches |
7/1/2014 | 6.62 | 31 | 6.6200000 | inches |
8/1/2014 | 6.26 | 28 | 6.2600000 | inches |
9/1/2014 | 11.60 | 26 | 11.6000000 | inches |
10/1/2014 | 4.11 | 30 | 4.1100000 | inches |
11/1/2014 | 3.59 | 30 | 3.5900000 | inches |
12/1/2014 | 0.16 | 31 | 0.1600000 | inches |
1/1/2015 | 1.17 | 31 | 1.1700000 | inches |
2/1/2015 | 3.61 | 28 | 3.6100000 | inches |
3/1/2015 | 1.21 | 31 | 1.2100000 | inches |
4/1/2015 | 1.35 | 30 | 1.3500000 | inches |
5/1/2015 | 4.40 | 31 | 4.4000000 | inches |
6/1/2015 | 5.01 | 30 | 5.0100000 | inches |
7/1/2015 | 14.96 | 31 | 14.9600000 | inches |
8/1/2015 | 7.70 | 31 | 7.7000000 | inches |
9/1/2015 | 8.51 | 30 | 8.5100000 | inches |
10/1/2015 | 5.31 | 31 | 5.3100000 | inches |
11/1/2015 | 0.75 | 30 | 0.7500000 | inches |
12/1/2015 | 2.01 | 31 | 2.0100000 | inches |
Salinity
Units: PSS |
Year 2015 |
Historical period of record |
High |
36.10 |
38.50 |
Mean |
27.39 |
30.56
7.9942
|
Low |
0.40 |
0.10 |
No. of Samples |
48 |
608 |
Target |
|
|
Threshold |
|
|
MDL |
0.10 |
0.10 |
GeoMean |
22.6258 |
22.6258 |
Five-year Trend Graph
| | | | |
---|
1/1/2011 | 32.18 | 4 | 32.1800000 | PSS |
2/1/2011 | 32.63 | 4 | 32.4100000 | PSS |
3/1/2011 | 34.03 | 4 | 32.9500000 | PSS |
4/1/2011 | 32.00 | 4 | 32.7100000 | PSS |
5/1/2011 | 33.40 | 4 | 32.8500000 | PSS |
6/1/2011 | 34.98 | 4 | 33.2000000 | PSS |
7/1/2011 | 30.95 | 4 | 33.0000000 | PSS |
8/1/2011 | 30.20 | 4 | 32.5900000 | PSS |
9/1/2011 | 22.83 | 4 | 30.7300000 | PSS |
10/1/2011 | 30.55 | 4 | 30.4900000 | PSS |
11/1/2011 | 33.95 | 4 | 30.5800000 | PSS |
12/1/2011 | 33.63 | 4 | 30.3500000 | PSS |
1/1/2012 | 34.48 | 4 | 30.9400000 | PSS |
2/1/2012 | 33.90 | 4 | 31.5600000 | PSS |
3/1/2012 | 35.33 | 4 | 33.6400000 | PSS |
4/1/2012 | 36.23 | 4 | 34.5900000 | PSS |
5/1/2012 | 36.45 | 4 | 35.0000000 | PSS |
6/1/2012 | 34.53 | 4 | 35.1500000 | PSS |
7/1/2012 | 20.68 | 4 | 32.8500000 | PSS |
8/1/2012 | 26.73 | 4 | 31.6600000 | PSS |
9/1/2012 | 24.53 | 4 | 29.8600000 | PSS |
10/1/2012 | 31.03 | 4 | 28.9900000 | PSS |
11/1/2012 | 29.40 | 4 | 27.8200000 | PSS |
12/1/2012 | 33.33 | 4 | 27.6200000 | PSS |
1/1/2013 | 33.03 | 4 | 29.6800000 | PSS |
2/1/2013 | 34.18 | 4 | 30.9200000 | PSS |
3/1/2013 | 34.30 | 4 | 32.5500000 | PSS |
4/1/2013 | 33.88 | 4 | 33.0200000 | PSS |
5/1/2013 | 33.08 | 4 | 33.6300000 | PSS |
6/1/2013 | 29.38 | 4 | 32.9800000 | PSS |
7/1/2013 | 13.60 | 4 | 29.7400000 | PSS |
8/1/2013 | 21.45 | 4 | 27.6200000 | PSS |
9/1/2013 | 20.38 | 4 | 25.3000000 | PSS |
10/1/2013 | 16.53 | 4 | 22.4000000 | PSS |
11/1/2013 | 32.15 | 4 | 22.2500000 | PSS |
12/1/2013 | 33.73 | 4 | 22.9700000 | PSS |
1/1/2014 | 33.78 | 4 | 26.3400000 | PSS |
2/1/2014 | 32.18 | 4 | 28.1300000 | PSS |
3/1/2014 | 34.23 | 4 | 30.4300000 | PSS |
4/1/2014 | 31.43 | 4 | 32.9200000 | PSS |
5/1/2014 | 30.53 | 4 | 32.6500000 | PSS |
6/1/2014 | 33.20 | 4 | 32.5600000 | PSS |
7/1/2014 | 31.40 | 4 | 32.1600000 | PSS |
8/1/2014 | 27.60 | 4 | 31.4000000 | PSS |
9/1/2014 | 30.05 | 4 | 30.7000000 | PSS |
10/1/2014 | 13.95 | 4 | 27.7900000 | PSS |
11/1/2014 | 31.33 | 4 | 27.9200000 | PSS |
12/1/2014 | 31.93 | 4 | 27.7100000 | PSS |
1/1/2015 | 32.53 | 4 | 27.9000000 | PSS |
2/1/2015 | 29.93 | 4 | 28.2900000 | PSS |
3/1/2015 | 30.60 | 4 | 28.3800000 | PSS |
4/1/2015 | 33.55 | 4 | 31.6500000 | PSS |
5/1/2015 | 34.38 | 4 | 32.1500000 | PSS |
6/1/2015 | 29.78 | 4 | 31.8000000 | PSS |
7/1/2015 | 33.65 | 4 | 31.9800000 | PSS |
8/1/2015 | 16.60 | 4 | 29.7600000 | PSS |
9/1/2015 | 14.70 | 4 | 27.1100000 | PSS |
10/1/2015 | 18.60 | 4 | 24.6200000 | PSS |
11/1/2015 | 21.23 | 4 | 22.4300000 | PSS |
12/1/2015 | 33.15 | 4 | 22.9900000 | PSS |
Turbidity
Units: NTU |
Year 2015 |
Historical period of record |
High |
12.00 |
23.00 |
Mean |
4.41 |
4.23
2.66022
|
Low |
2.00 |
0.35 |
No. of Samples |
50 |
640 |
Target |
|
|
Threshold |
|
|
MDL |
0.20 |
0.20 |
GeoMean |
4.1358 |
4.1358 |
Five-year Trend Graph
| | | | |
---|
1/1/2011 | 4.45 | 4 | 4.4500000 | NTU |
2/1/2011 | 8.93 | 4 | 6.6900000 | NTU |
3/1/2011 | 5.43 | 4 | 6.2700000 | NTU |
4/1/2011 | 11.48 | 4 | 7.5700000 | NTU |
5/1/2011 | 4.45 | 4 | 6.9500000 | NTU |
6/1/2011 | 3.48 | 4 | 6.3700000 | NTU |
7/1/2011 | 4.53 | 4 | 6.3800000 | NTU |
8/1/2011 | 6.80 | 4 | 6.0300000 | NTU |
9/1/2011 | 3.43 | 4 | 5.7000000 | NTU |
10/1/2011 | 3.28 | 4 | 4.3300000 | NTU |
11/1/2011 | 4.00 | 4 | 4.2500000 | NTU |
12/1/2011 | 3.70 | 4 | 4.2900000 | NTU |
1/1/2012 | 3.08 | 4 | 4.0500000 | NTU |
2/1/2012 | 3.73 | 4 | 3.5400000 | NTU |
3/1/2012 | 6.17 | 3 | 3.9900000 | NTU |
4/1/2012 | 5.03 | 4 | 4.2900000 | NTU |
5/1/2012 | 5.43 | 4 | 4.5200000 | NTU |
6/1/2012 | 4.40 | 4 | 4.6400000 | NTU |
7/1/2012 | 3.83 | 4 | 4.7700000 | NTU |
8/1/2012 | 3.15 | 4 | 4.6700000 | NTU |
9/1/2012 | 3.44 | 5 | 4.2100000 | NTU |
10/1/2012 | 3.30 | 4 | 3.9300000 | NTU |
11/1/2012 | 3.58 | 5 | 3.6200000 | NTU |
12/1/2012 | 3.48 | 4 | 3.4600000 | NTU |
1/1/2013 | 2.93 | 4 | 3.3100000 | NTU |
2/1/2013 | 3.45 | 4 | 3.3600000 | NTU |
3/1/2013 | 7.45 | 4 | 4.0300000 | NTU |
4/1/2013 | 2.48 | 4 | 3.9000000 | NTU |
5/1/2013 | 5.40 | 4 | 4.2000000 | NTU |
6/1/2013 | 3.93 | 4 | 4.2700000 | NTU |
7/1/2013 | 2.95 | 4 | 4.2800000 | NTU |
8/1/2013 | 2.93 | 4 | 4.1900000 | NTU |
9/1/2013 | 4.33 | 4 | 3.6700000 | NTU |
10/1/2013 | 6.03 | 4 | 4.2600000 | NTU |
11/1/2013 | 5.45 | 4 | 4.2700000 | NTU |
12/1/2013 | 3.50 | 4 | 4.2000000 | NTU |
1/1/2014 | 4.35 | 4 | 4.4300000 | NTU |
2/1/2014 | 2.85 | 4 | 4.4200000 | NTU |
3/1/2014 | 3.39 | 4 | 4.2600000 | NTU |
4/1/2014 | 8.78 | 4 | 4.7200000 | NTU |
5/1/2014 | 3.75 | 4 | 4.4400000 | NTU |
6/1/2014 | 4.80 | 4 | 4.6500000 | NTU |
7/1/2014 | 3.95 | 4 | 4.5900000 | NTU |
8/1/2014 | 4.98 | 4 | 4.9400000 | NTU |
9/1/2014 | 3.13 | 4 | 4.9000000 | NTU |
10/1/2014 | 4.38 | 4 | 4.1700000 | NTU |
11/1/2014 | 3.60 | 4 | 4.1400000 | NTU |
12/1/2014 | 7.20 | 4 | 4.5400000 | NTU |
1/1/2015 | 5.04 | 5 | 4.7200000 | NTU |
2/1/2015 | 6.75 | 4 | 5.0200000 | NTU |
3/1/2015 | 4.23 | 4 | 5.2000000 | NTU |
4/1/2015 | 3.93 | 4 | 5.1300000 | NTU |
5/1/2015 | 5.88 | 4 | 5.5100000 | NTU |
6/1/2015 | 4.50 | 4 | 5.0600000 | NTU |
7/1/2015 | 4.60 | 4 | 4.9800000 | NTU |
8/1/2015 | 4.38 | 4 | 4.5900000 | NTU |
9/1/2015 | 3.68 | 4 | 4.5000000 | NTU |
10/1/2015 | 3.63 | 4 | 4.4500000 | NTU |
11/1/2015 | 3.18 | 5 | 4.0000000 | NTU |
12/1/2015 | 3.28 | 4 | 3.7900000 | NTU |
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 (2015)
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.
Loading interactive contour map viewer...
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.
Loading interactive seagrass coverage viewer...
Year | Acres |
1948 |
132.738072 |
1988 |
47.351 |
1994 |
58.637 |
1996 |
66.2119 |
1999 |
87.23853 |
2001 |
83.943443 |
2004 |
102.462343 |
2006 |
123.222818 |
2008 |
89.334667 |
2010 |
78.364281 |
2012 |
78.807574 |
2014 |
98.816992 |
2016 |
100.74333 |
Loading interactive chart...

Target
112 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.
Dona/Roberts Bay is located within the Dona and Roberts Bay Watershed. The chart below shows the land use / land cover characteristics for Dona and Roberts Bay Watershed within the boundary of this Water Atlas. View details about the Dona and Roberts Bay Watershed »
Year | Name | Area | Percent |
2011 | Urban & Built-up | 17696.705078125 | 31.6 |
2011 | Agriculture | 13409.662109375 | 24 |
2011 | Rangeland | 2104.44775390625 | 3.8 |
2011 | Upland Forests | 7742.46142578125 | 13.8 |
2011 | Water | 2813.03735351563 | 5 |
2011 | Wetlands | 9907.3662109375 | 17.7 |
2011 | Barren Land | 83.9428024291992 | 0.2 |
2011 | Transportation and Utilities | 2184.99267578125 | 3.9 |
Loading interactive chart...