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Cow Pen Slough Condition Report for 2012

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Pass

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: 47,518 acres
  • Location: North and central Sarasota County, south Manatee County
  • Discharges into: Dona Bay

The hydrologic boundary of the Cow Pen Slough Basin is indeterminate in many areas due to the flat topography and undefined drainageways. Drainage from the basin is conveyed through 14 miles of improved channel. There are two operational flood control structures on the channel which were designed to provide grade control and water conservation. At present the Cow Pen Slough Basin is primarily rural in nature, with the majority of the land uses being classified as rangeland, crop and pastureland, orchards and groves, and upland forests. There are localized areas that are primarily urban in nature around Bee Ridge and north of Venice, with the majority being classified as residential. For basin details see: Cow Pen Slough Basin Master Plan (USDA Report, 1997)

Creek Location Map

Water Chemistry Ratings - Freshwater Portion of the Creek

Total nitrogen, total phosphorus, chlorophyll a, and dissolved oxygen levels are monitored carefully by water resource managers and used by regulatory authorities to determine whether a creek meets the water quality standards mandated by the Clean Water Act. Shown below are water quality data for each freshwater stream segment. Florida law defines a threshold for the maximum allowable concentration of nitrogen, phosphorus, and chlorophyll a, and the minimum required 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:
  • 1924
  • 1924B
  • 1987
  • 1994
  • 1996
  • 2004
Pass

Chlorophyll a

Score: Pass
Units: mg/l Year
2012
Historical
period of record
High 0.145 0.243
Mean 0.0116 0.0121 0.02374491
Low 0.0009 0.0006
No. of Samples 30 259

Five-year Trend Graph

      
1/1/20087.6730.0076700mg/l0.0053900
2/1/200811.4840.0095800mg/l0.0076900
3/1/20089.5640.0095700mg/l0.0084400
4/1/200814.2850.0107500mg/l0.0119000
5/1/200831.8650.0149700mg/l0.0275400
6/1/200843.9840.0198100mg/l0.0380300
7/1/200826.1840.0228900mg/l0.0241900
8/1/200814.7240.0234300mg/l0.0090900
9/1/200880.6040.0352700mg/l0.0426700
10/1/200828.9150.0377100mg/l0.0198700
11/1/200816.4740.0351400mg/l0.0143900
12/1/200810.3030.0295300mg/l0.0096100
1/1/200914.1030.0275200mg/l0.0136300
2/1/200932.3330.0304500mg/l0.0196800
3/1/20099.7620.0186500mg/l0.0097500
4/1/200911.5930.0157600mg/l0.0095900
5/1/200916.1330.0157000mg/l0.0158500
6/1/200933.6530.0195900mg/l0.0234200
7/1/200920.4530.0206500mg/l0.0146500
8/1/200922.7130.0190500mg/l0.0157300
9/1/20097.6430.0187000mg/l0.0076100
10/1/20095.9230.0177500mg/l0.0051000
11/1/200929.9330.0200500mg/l0.0273300
12/1/200939.2730.0209900mg/l0.0289200
1/1/20103.3930.0181400mg/l0.0028000
2/1/201013.8430.0166700mg/l0.0123800
3/1/20108.7430.0168500mg/l0.0085900
4/1/201025.9730.0201900mg/l0.0237700
6/1/201026.5030.0156900mg/l0.0262200
7/1/201020.5030.0191100mg/l0.0195100
9/1/201019.6460.0231500mg/l0.0146700
10/1/201010.8130.0193600mg/l0.0047700
11/1/20104.1930.0163300mg/l0.0035700
12/1/201027.3930.0165100mg/l0.0126100
1/1/20117.9130.0139900mg/l0.0071300
2/1/201113.6530.0139300mg/l0.0130800
3/1/201118.9030.0138100mg/l0.0161900
4/1/20118.3730.0134000mg/l0.0079100
5/1/201123.4330.0166100mg/l0.0126600
6/1/201129.5030.0169600mg/l0.0230800
7/1/201122.5730.0194000mg/l0.0218800
8/1/20115.3330.0180200mg/l0.0052800
9/1/20117.8730.0161800mg/l0.0057900
10/1/20116.2330.0158200mg/l0.0047900
11/1/20116.1030.0129300mg/l0.0057800
12/1/20115.4330.0089200mg/l0.0053100
1/1/201219.5830.0084200mg/l0.0106700
2/1/201242.8730.0146800mg/l0.0282000
3/1/201217.6550.0163100mg/l0.0166400
4/1/201211.3430.0171600mg/l0.0112400
5/1/201228.2520.0208500mg/l0.0222200
6/1/201280.0520.0332900mg/l0.0467900
7/1/20125.5520.0309500mg/l0.0055300
8/1/20125.7620.0247700mg/l0.0054900
9/1/20123.5720.0224200mg/l0.0023700
10/1/20123.7820.0211600mg/l0.0037500
11/1/201220.9920.0199500mg/l0.0175400
12/1/20128.5420.0080300mg/l0.0081700
Target
mg/l
Threshold
0.02 mg/l
Pass

Nitrogen, Total

Score: Pass
Units: mg/l Year
2012
Historical
period of record
High 1.976 2.73
Mean 0.9405 0.9689 0.44590406
Low 0.472 0.15
No. of Samples 28 319

Five-year Trend Graph

      
1/1/2008619.3330.6193300mg/l0.5757700
2/1/2008691.6340.6554800mg/l0.6242100
3/1/2008512.5040.6078200mg/l0.4631100
4/1/2008954.6050.6945200mg/l0.8755100
5/1/20081341.2050.8238500mg/l1.1703200
6/1/20081269.0040.8980400mg/l1.1503200
7/1/20081323.5041.0154100mg/l1.2975600
8/1/20081484.7541.1475900mg/l1.4780900
9/1/20081595.0041.3280100mg/l1.4992700
10/1/2008976.2051.3316100mg/l0.8835300
11/1/2008738.6341.2311800mg/l0.6469300
12/1/2008736.6731.1424600mg/l0.7087800
1/1/2009531.6731.0104900mg/l0.4739600
2/1/2009872.0030.9083600mg/l0.5159100
3/1/2009780.5020.7726100mg/l0.7484100
4/1/2009810.0030.7449100mg/l0.7695900
5/1/20091161.3330.8153600mg/l1.1429800
6/1/20091555.0030.9517500mg/l1.5197600
7/1/20091582.3331.1268600mg/l1.5026800
8/1/20091130.3331.1699200mg/l1.1246300
9/1/20091256.3331.2492200mg/l1.2119600
10/1/2009833.6731.2531700mg/l0.8104300
11/1/20091049.3331.2345000mg/l1.0385700
12/1/20091259.0031.1851700mg/l1.2504700
1/1/20101054.3331.0971700mg/l1.0488100
2/1/20101077.6731.0883900mg/l1.0699800
3/1/20101743.6731.1696100mg/l1.7385400
4/1/20101257.6731.2402800mg/l1.2456300
6/1/20101259.0031.2784700mg/l1.2273400
7/1/2010930.3331.2536700mg/l0.9225400
9/1/20101438.0061.2212500mg/l1.4247200
10/1/20101022.3331.1624200mg/l1.0211100
11/1/2010816.3331.0932000mg/l0.8067900
12/1/2010982.3331.0378600mg/l0.9024100
1/1/2011778.3331.0074600mg/l0.7667700
2/1/2011899.0030.9893900mg/l0.8928100
3/1/20111195.3330.9489400mg/l1.1193900
4/1/20111167.3330.9731100mg/l1.1543100
5/1/20111328.6731.0585000mg/l1.2395000
6/1/20111170.6731.0898900mg/l1.0905900
7/1/20111133.0031.1490000mg/l1.1274600
8/1/20111478.0031.2455000mg/l1.4653300
9/1/20111543.0031.3034500mg/l1.5348000
10/1/20111009.3331.2771100mg/l1.0038700
11/1/2011774.6731.1847800mg/l0.7739200
12/1/2011676.3331.1023900mg/l0.6757200
1/1/2012653.3331.0224400mg/l0.6518300
2/1/2012951.3330.9346700mg/l0.9231000
3/1/2012919.0040.8306700mg/l0.8981300
4/1/20121008.6730.8305600mg/l0.9326400
5/1/2012773.0020.8302800mg/l0.7119900
6/1/20121486.0020.9652200mg/l1.4028900
7/1/20121153.0011.0485000mg/l1.1530000
8/1/20121490.0021.1382800mg/l1.4516200
9/1/20121269.5021.1967000mg/l1.2631800
10/1/20121365.5021.2561700mg/l1.3441500
11/1/2012661.0021.2375000mg/l0.6578000
12/1/2012718.5021.1095800mg/l0.7180500
Pass

Phosphorus, Total

Score: Pass
Units: mg/l Year
2012
Historical
period of record
High 0.497 1.19
Mean 0.1504 0.2028 0.19509566
Low 0.039 0.02
No. of Samples 23 275

Five-year Trend Graph

      
1/1/2008113.0030.1130000mg/l0.1020300
2/1/2008156.7540.1348800mg/l0.1527900
3/1/200892.5040.1207500mg/l0.0855100
4/1/2008242.0050.1510600mg/l0.1986000
5/1/2008374.4050.1957300mg/l0.3429000
6/1/2008624.0040.2671100mg/l0.5682300
7/1/2008525.7540.3359000mg/l0.4878100
8/1/2008264.7540.3539000mg/l0.2633500
9/1/2008449.5040.4134000mg/l0.4015800
10/1/2008398.0050.4394000mg/l0.3814400
11/1/2008175.5040.4062500mg/l0.1655200
12/1/2008100.3330.3189700mg/l0.0989700
1/1/200964.0030.2420100mg/l0.0639800
2/1/200977.6730.2108300mg/l0.0698300
3/1/200978.5020.1490000mg/l0.0780400
4/1/200974.3330.0950600mg/l0.0730400
5/1/2009372.3330.1278600mg/l0.3525700
6/1/2009915.6730.2637500mg/l0.8527500
7/1/2009440.3330.3264700mg/l0.4319700
8/1/2009232.3330.3522500mg/l0.2317800
9/1/2009207.3330.3737200mg/l0.1874800
10/1/2009136.3330.3840500mg/l0.1154600
11/1/2009180.3330.3520500mg/l0.1718400
12/1/2009127.3330.2206600mg/l0.1258000
1/1/2010100.6730.1640500mg/l0.0960100
2/1/2010130.6730.1471100mg/l0.1256700
3/1/2010354.0030.1715600mg/l0.3516400
4/1/2010266.3330.1932200mg/l0.2638600
6/1/2010339.3330.2382000mg/l0.3267200
7/1/2010167.3330.2515300mg/l0.1660100
9/1/2010334.3360.2768300mg/l0.3310300
10/1/2010205.6730.2616700mg/l0.2008400
11/1/2010116.3330.2326000mg/l0.1110900
12/1/2010101.0030.1849300mg/l0.0954200
1/1/201191.3330.1697300mg/l0.0875500
2/1/2011104.0030.1587800mg/l0.0960900
3/1/2011137.0030.1258900mg/l0.1166500
4/1/2011398.6730.1580600mg/l0.3735700
5/1/2011317.6730.1916100mg/l0.2796900
6/1/2011397.0030.2409500mg/l0.3826200
7/1/2011514.0030.3113900mg/l0.4936700
8/1/2011390.0030.3590600mg/l0.3892000
9/1/2011465.0030.4137200mg/l0.4595000
10/1/2011293.3330.3961700mg/l0.2881500
11/1/2011115.0030.3623900mg/l0.1075700
12/1/201196.6730.3123300mg/l0.0833300
1/1/201266.6730.2377800mg/l0.0595800
2/1/201291.6730.1880600mg/l0.0885900
3/1/2012152.0040.1358900mg/l0.1453600
4/1/2012144.3330.1110600mg/l0.1431500
5/1/2012119.5020.1118100mg/l0.1194200
6/1/2012389.0020.1605300mg/l0.3737100
7/1/2012200.0010.1827500mg/l0.2000000
8/1/2012209.5020.2023900mg/l0.2002700
9/1/2012165.5020.2046400mg/l0.1614200
10/1/2012168.5020.2086700mg/l0.1684600
11/1/201274.0020.2010800mg/l0.0640900
12/1/2012103.5020.1535000mg/l0.1014500
Target
mg/l
Threshold
0.49 mg/l
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
2012
Historical
period of record
High 152.20 227.16
Mean 65.65 71.23 34.59025
Low 6.90 2.381
No. of Samples 24 480

Five-year Trend Graph

      
1/1/200892.27392.2700000percent (%)91.9400000
2/1/200887.83490.0500000percent (%)86.2600000
3/1/200856.48478.8600000percent (%)33.1900000
4/1/200880.50579.2700000percent (%)74.0200000
5/1/2008125.60288.5400000percent (%)125.1700000
6/1/200896.60189.8800000percent (%)96.6000000
7/1/200868.05485.8400000percent (%)50.6500000
8/1/200851.83479.8400000percent (%)44.7800000
9/1/200896.45486.5100000percent (%)88.8200000
10/1/200895.72589.0400000percent (%)89.2800000
11/1/200883.20381.9800000percent (%)82.8800000
12/1/200866.63376.9800000percent (%)64.4200000
1/1/2009108.53383.7300000percent (%)108.3500000
2/1/2009108.53393.1800000percent (%)105.1000000
3/1/200990.50292.1900000percent (%)88.6300000
4/1/200980.50389.6500000percent (%)76.2300000
5/1/200962.50386.2000000percent (%)60.3700000
6/1/200981.33388.6500000percent (%)71.3400000
7/1/200936.50376.6400000percent (%)29.6800000
8/1/200969.03370.0600000percent (%)63.6200000
9/1/200959.20364.8400000percent (%)57.8000000
10/1/200963.03361.9300000percent (%)60.3200000
11/1/2009122.45271.9200000percent (%)115.7200000
12/1/2009115.77377.6600000percent (%)110.2200000
1/1/201086.93386.0700000percent (%)86.2800000
2/1/201096.70390.6800000percent (%)96.4100000
3/1/201077.10393.6600000percent (%)75.8400000
4/1/201096.53399.2500000percent (%)96.5200000
7/1/201094.45291.2000000percent (%)94.4100000
9/1/201081.97390.9800000percent (%)80.9300000
11/1/201089.53388.6500000percent (%)88.1000000
12/1/2010105.70292.9100000percent (%)105.2000000
1/1/201184.70390.4800000percent (%)81.7800000
2/1/201197.83391.9500000percent (%)88.1400000
3/1/201178.63391.2800000percent (%)77.0600000
4/1/201176.70388.8500000percent (%)68.0900000
5/1/201148.30381.9800000percent (%)47.4400000
1/1/201296.90396.9000000percent (%)95.5600000
2/1/201267.33382.1200000percent (%)66.8600000
3/1/2012102.00388.7400000percent (%)96.5400000
4/1/201274.83385.2700000percent (%)73.8000000
5/1/201280.00284.2100000percent (%)79.5500000
6/1/201238.95276.6700000percent (%)22.1300000
8/1/201245.55268.2700000percent (%)44.3800000
10/1/201258.10255.6500000percent (%)56.8700000
11/1/201295.50259.5300000percent (%)93.7900000
12/1/201250.50262.4100000percent (%)50.0800000
Target
percent (%)
Threshold
38.00 percent (%)

Rainfall

Units: inches Year
2012
Historical
period of record
High 40.97 70.27
Mean 21.4880915576018
Low 3.15
No. of Samples 357 3,511

Five-year Trend Graph

      
1/1/20082.06312.0600000inches2.0600000
2/1/20081.44291.4400000inches1.4400000
3/1/20082.46312.4600000inches2.4600000
4/1/20082.97302.9700000inches2.9700000
5/1/20082.75312.7500000inches2.7500000
6/1/20083.18303.1800000inches3.1800000
7/1/20089.50319.5000000inches9.5000000
8/1/20089.19319.1900000inches9.1900000
9/1/20083.77303.7700000inches3.7700000
10/1/20081.90311.9000000inches1.9000000
11/1/20080.53300.5300000inches0.5300000
12/1/20081.66311.6600000inches1.6600000
1/1/20090.75310.7500000inches0.7500000
2/1/20090.50280.5000000inches0.5000000
3/1/20090.90310.9000000inches0.9000000
4/1/20091.21301.2100000inches1.2100000
5/1/20096.79316.7900000inches6.7900000
6/1/20094.67304.6700000inches4.6700000
7/1/20095.87315.8700000inches5.8700000
8/1/20096.18316.1800000inches6.1800000
9/1/20096.87306.8700000inches6.8700000
10/1/20090.92310.9200000inches0.9200000
11/1/20092.10302.1000000inches2.1000000
12/1/20094.23314.2300000inches4.2300000
1/1/20102.89312.8900000inches2.8900000
2/1/20102.40282.4000000inches2.4000000
3/1/20106.78316.7800000inches6.7800000
4/1/20101.84301.8400000inches1.8400000
5/1/20101.63311.6300000inches1.6300000
6/1/20104.08304.0800000inches4.0800000
7/1/20106.90316.9000000inches6.9000000
8/1/201010.553110.5500000inches10.5500000
9/1/20103.29303.2900000inches3.2900000
10/1/20100.00310.0000000inches0.0000000
11/1/20101.29301.2900000inches1.2900000
12/1/20100.79310.7900000inches0.7900000
1/1/20112.64312.6400000inches2.6400000
2/1/20110.35280.3500000inches0.3500000
3/1/20118.10318.1000000inches8.1000000
4/1/20111.56301.5600000inches1.5600000
5/1/20112.10312.1000000inches2.1000000
6/1/20112.32302.3200000inches2.3200000
7/1/20117.43317.4300000inches7.4300000
8/1/20117.38317.3800000inches7.3800000
9/1/20117.31307.3100000inches7.3100000
10/1/20112.24312.2400000inches2.2400000
11/1/20111.46301.4600000inches1.4600000
12/1/20110.08310.0800000inches0.0800000
1/1/20120.82300.8200000inches0.8200000
2/1/20120.59290.5900000inches0.5900000
3/1/20121.17311.1700000inches1.1700000
4/1/20122.57242.5700000inches2.5700000
5/1/20120.76310.7600000inches0.7600000
6/1/201213.503013.5000000inches13.5000000
7/1/20126.18316.1800000inches6.1800000
8/1/20129.35319.3500000inches9.3500000
9/1/20122.44302.4400000inches2.4400000
10/1/20121.44311.4400000inches1.4400000
11/1/20120.03280.0300000inches0.0300000
12/1/20122.12312.1200000inches2.1200000
Target
inches
Threshold
inches

Salinity

Units: PSS Year
2012
Historical
period of record
High 36.21 76.50
Mean 1.53 27.36 14.41658
Low 0.14 0.00
No. of Samples 24 3,394

Five-year Trend Graph

      
1/1/20089.2839.2800000PSS1.7500000
2/1/20087.3148.3000000PSS1.3000000
3/1/20088.0348.2100000PSS1.2800000
4/1/20086.5857.8000000PSS0.9700000
5/1/20080.4126.3200000PSS0.4000000
6/1/20080.3915.3300000PSS0.3900000
7/1/20085.7844.7500000PSS0.8000000
8/1/20080.8843.6800000PSS0.3300000
9/1/20082.1042.6900000PSS0.7000000
10/1/20084.7652.3900000PSS0.7700000
11/1/20086.2543.3600000PSS0.9900000
12/1/20087.2234.5000000PSS1.3400000
1/1/200910.5935.3000000PSS1.7500000
2/1/200910.2536.8600000PSS1.8100000
3/1/200912.9228.6700000PSS3.9900000
4/1/200911.8239.8400000PSS2.2400000
5/1/20097.43310.0400000PSS1.7000000
6/1/20098.29310.2200000PSS1.4700000
7/1/20095.5139.3700000PSS0.7600000
8/1/20092.9538.1500000PSS0.5300000
9/1/20090.3536.0600000PSS0.3400000
10/1/20099.7035.7100000PSS1.4300000
11/1/20099.7926.1000000PSS2.8400000
12/1/20093.4935.3000000PSS0.9300000
1/1/20102.7534.8400000PSS0.8700000
2/1/20103.6134.9500000PSS0.9400000
3/1/20100.2934.9400000PSS0.2700000
4/1/20106.2134.3600000PSS1.2500000
7/1/20100.3622.6200000PSS0.3600000
9/1/20104.1833.5800000PSS0.9500000
11/1/201010.9535.1600000PSS1.6200000
12/1/201015.5927.7700000PSS3.4200000
1/1/20116.3839.2800000PSS1.3700000
2/1/20119.9839.4200000PSS1.7000000
3/1/20119.80310.5400000PSS1.7100000
4/1/20116.9739.9500000PSS1.2600000
5/1/201110.7439.9100000PSS1.5800000
1/1/20120.3330.3300000PSS0.2900000
2/1/201210.7235.5300000PSS1.8500000
3/1/201211.5037.5200000PSS1.8800000
4/1/201211.8438.6000000PSS1.9600000
5/1/201218.33210.5400000PSS3.9900000
6/1/201210.35210.5100000PSS2.7100000
8/1/20120.28210.4600000PSS0.2700000
10/1/20125.7128.6700000PSS1.7300000
11/1/201215.2527.9000000PSS3.4300000
12/1/201214.5028.9400000PSS3.3800000

Turbidity

Units: NTU Year
2012
Historical
period of record
High 9.40 48.00
Mean 3.05 2.65 4.00842
Low 1.00 0.40
No. of Samples 28 463

Five-year Trend Graph

      
1/1/20081.7131.7100000NTU1.5200000
2/1/20083.5642.6400000NTU2.7800000
3/1/20082.1842.4800000NTU1.8200000
4/1/20082.4252.4700000NTU1.8200000
5/1/20085.6453.1000000NTU4.1100000
6/1/20086.2343.6200000NTU5.3900000
7/1/20084.1044.0200000NTU3.8500000
8/1/20083.9844.0900000NTU3.9100000
9/1/20085.8044.7000000NTU5.2900000
10/1/20083.2254.8300000NTU3.0700000
11/1/20082.6044.3200000NTU2.5700000
12/1/20081.3833.5100000NTU1.3600000
1/1/20092.0533.1700000NTU1.9200000
2/1/20095.1933.3700000NTU3.5900000
3/1/20091.9122.7300000NTU1.9000000
4/1/20092.0232.5300000NTU1.8500000
5/1/20092.5032.5100000NTU2.3700000
6/1/20093.4732.8600000NTU3.3300000
7/1/20094.5033.2700000NTU4.0400000
8/1/20092.9232.8900000NTU2.4100000
9/1/20092.7733.0300000NTU2.6600000
10/1/20092.0233.0300000NTU2.0200000
11/1/20095.5333.5400000NTU5.1600000
12/1/20093.3033.5100000NTU3.2300000
1/1/20102.6733.2000000NTU2.6300000
2/1/20102.7333.1700000NTU2.6900000
3/1/20103.8733.3500000NTU3.8600000
4/1/20105.6033.9500000NTU5.5500000
6/1/20106.0034.1700000NTU5.6300000
7/1/20105.5734.7500000NTU5.2900000
9/1/20105.0865.5600000NTU4.9600000
10/1/20103.8735.1300000NTU3.6100000
11/1/20102.0734.5200000NTU2.0600000
12/1/20103.9134.1000000NTU2.9200000
1/1/20112.8333.5500000NTU2.4500000
2/1/20113.1033.4800000NTU3.0700000
3/1/20117.8333.9400000NTU6.5600000
4/1/20113.2733.8400000NTU3.2300000
5/1/20114.1434.1800000NTU3.1100000
6/1/20113.5034.1100000NTU3.1800000
7/1/20113.5334.2300000NTU3.4300000
8/1/20113.5034.3000000NTU3.5000000
9/1/20113.4333.5600000NTU3.3000000
10/1/20112.8733.5000000NTU2.8000000
11/1/20112.1133.1600000NTU2.0700000
12/1/20111.2232.7800000NTU1.2100000
1/1/20121.8032.4900000NTU1.5400000
2/1/20125.1032.7600000NTU4.3200000
3/1/20123.2042.7200000NTU3.0900000
4/1/20123.2332.7800000NTU3.0000000
5/1/20123.0522.9300000NTU3.0500000
6/1/20125.5023.6500000NTU5.2900000
7/1/20128.2014.7100000NTU8.2000000
8/1/20123.4524.4400000NTU3.4400000
9/1/20124.2524.6100000NTU4.1200000
10/1/20123.6024.6800000NTU3.5300000
11/1/20121.9024.4800000NTU1.8600000
12/1/20121.7023.8500000NTU1.6900000
Other Measures of Creek Health

Water Chemistry Ratings - Tidal Portion of the Creek

As is the case for predominantly freshwater streams, total nitrogen, total phosphorus, and chlorophyll a levels are monitored carefully by water resource managers and used by regulatory authorities to determine whether a tidally-influenced stream meets the water quality standards mandated by the Clean Water Act. Shown below are water quality data for each saltwater water body within this basin. Florida law defines a threshold for the maximum allowable concentration of chlorophyll a and the minimum required concentration of dissolved oxygen in these streams. No thresholds have been established for the allowable concentration of nitrogen or phosphorus; trend information is provided for these nutrients, to determine whether a statistically significant trend exists and if so, whether levels are rising (bad) or falling (good). Learn more about these ratings and how they are calculated »

Data for the following WBIDs is averaged when compiling the data below:
  • 1924A

Chlorophyll a

Units: mg/l Year
2012
Historical
period of record
High
Mean
Low
No. of Samples

Five-year Trend Graph

     
Target
mg/l
Threshold
0.011 mg/l

Nitrogen, Total

We were unable to determine a trend for the data available.
Units: mg/l Year
2012
Historical
period of record
High
Mean
Low
No. of Samples

Five-year Trend Graph

     

Phosphorus, Total

We were unable to determine a trend for the data available.
Units: mg/l Year
2012
Historical
period of record
High
Mean
Low
No. of Samples

Five-year Trend Graph

     
Target
mg/l
Threshold
mg/l

Dissolved Oxygen Saturation

Note: Low DO saturation also may be naturally influenced by inflows from nearby wetlands or groundwater sources
Units: percent (%) Year
2012
Historical
period of record
High
Mean
Low
No. of Samples

Five-year Trend Graph

     
Target
percent (%)
Threshold
56.00 percent (%)

Oysters

Units: Year
2012
Historical
period of record
High
Mean
Low
No. of Samples

Five-year Trend Graph

     
1/1/200778.95178.9500000%78.9500000
1/1/200886.54186.5400000%86.5400000
1/1/200973.24173.2400000%73.2400000
1/1/201083.78183.7800000%83.7800000
1/1/201182.95182.9500000%82.9500000
1/1/201261.24161.2400000%61.2400000

Rainfall

Units: inches Year
2012
Historical
period of record
High 41.0 70.3
Mean 21.4880915576018
Low 3.15
No. of Samples 357 3,511

Five-year Trend Graph

     
1/1/20082.06312.0600000inches2.0600000
2/1/20081.44291.4400000inches1.4400000
3/1/20082.46312.4600000inches2.4600000
4/1/20082.97302.9700000inches2.9700000
5/1/20082.75312.7500000inches2.7500000
6/1/20083.18303.1800000inches3.1800000
7/1/20089.50319.5000000inches9.5000000
8/1/20089.19319.1900000inches9.1900000
9/1/20083.77303.7700000inches3.7700000
10/1/20081.90311.9000000inches1.9000000
11/1/20080.53300.5300000inches0.5300000
12/1/20081.66311.6600000inches1.6600000
1/1/20090.75310.7500000inches0.7500000
2/1/20090.50280.5000000inches0.5000000
3/1/20090.90310.9000000inches0.9000000
4/1/20091.21301.2100000inches1.2100000
5/1/20096.79316.7900000inches6.7900000
6/1/20094.67304.6700000inches4.6700000
7/1/20095.87315.8700000inches5.8700000
8/1/20096.18316.1800000inches6.1800000
9/1/20096.87306.8700000inches6.8700000
10/1/20090.92310.9200000inches0.9200000
11/1/20092.10302.1000000inches2.1000000
12/1/20094.23314.2300000inches4.2300000
1/1/20102.89312.8900000inches2.8900000
2/1/20102.40282.4000000inches2.4000000
3/1/20106.78316.7800000inches6.7800000
4/1/20101.84301.8400000inches1.8400000
5/1/20101.63311.6300000inches1.6300000
6/1/20104.08304.0800000inches4.0800000
7/1/20106.90316.9000000inches6.9000000
8/1/201010.553110.5500000inches10.5500000
9/1/20103.29303.2900000inches3.2900000
10/1/20100.00310.0000000inches0.0000000
11/1/20101.29301.2900000inches1.2900000
12/1/20100.79310.7900000inches0.7900000
1/1/20112.64312.6400000inches2.6400000
2/1/20110.35280.3500000inches0.3500000
3/1/20118.10318.1000000inches8.1000000
4/1/20111.56301.5600000inches1.5600000
5/1/20112.10312.1000000inches2.1000000
6/1/20112.32302.3200000inches2.3200000
7/1/20117.43317.4300000inches7.4300000
8/1/20117.38317.3800000inches7.3800000
9/1/20117.31307.3100000inches7.3100000
10/1/20112.24312.2400000inches2.2400000
11/1/20111.46301.4600000inches1.4600000
12/1/20110.08310.0800000inches0.0800000
1/1/20120.82300.8200000inches0.8200000
2/1/20120.59290.5900000inches0.5900000
3/1/20121.17311.1700000inches1.1700000
4/1/20122.57242.5700000inches2.5700000
5/1/20120.76310.7600000inches0.7600000
6/1/201213.503013.5000000inches13.5000000
7/1/20126.18316.1800000inches6.1800000
8/1/20129.35319.3500000inches9.3500000
9/1/20122.44302.4400000inches2.4400000
10/1/20121.44311.4400000inches1.4400000
11/1/20120.03280.0300000inches0.0300000
12/1/20122.12312.1200000inches2.1200000
Target
inches
Threshold
inches

Salinity

Units: PSS Year
2012
Historical
period of record
High
Mean
Low
No. of Samples

Five-year Trend Graph

     

Turbidity

Units: NTU Year
2012
Historical
period of record
High
Mean
Low
No. of Samples

Five-year Trend Graph

     
Other Measures of Creek Health

Oysters

Because they are immobile and will tolerate a fairly wide salinity range, eastern oysters (Crassotrea 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 SKC4 2012 169 267 436 61

Impervious Features

Cow Pen Slough 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.

of the land area within the Cow Pen Slough Basin is covered by impervious surfaces.

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Land Use / Land Cover

Cow Pen Slough 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 »

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Data Sources

The data sources listed below provided water quality data used to create the report on this page. Not all data sources provided data for every creek, and not every Creek Conditions Report used data from all listed data sources. While some data sources have no data for the scored year, they provided period-of-record (historical high, mean, low) data. Click on a data source name to review its metadata.