Louisiana Assessment Data for 2008

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Louisiana Assessment Summary
Water Quality by Waterbody Type
Causes of Impairment
Probable Sources Contributing to Impairments
TMDL Alternatives by Cause of Impairment

Data are also available for these cycles:
2002 2004 2006 2010

For More Information:

Louisiana Assessment Report
State Water Quality Program

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Assessed Waters of Louisiana by Watershed

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Features

Site-specific Targeted Monitoring Summary Results

Louisiana (2008)

Description of this table

	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)	Wetlands (Acres)
	Size of Water
Good Waters	1,811.2	22,921.0	2,885.0	627,200.0
Previously impaired waters now attaining all uses	1,782.0	29,024.0	517.5
Threatened Waters
TMDL completed
TMDL alternative
Non-pollutant impairment
TMDL needed
Impaired Waters	7,610.2	647,668.0	2,068.5	402,560.0
TMDL completed	1,483.4	308,214.0	1,062.0
TMDL alternative	50.3		91.0
Non-pollutant impairment
TMDL needed	6,076.5	339,454.0	915.5	402,560.0

Total Assessed Waters	9,421.4	670,589.0	4,953.5	1,029,760.0
Total Waters	66,294.0	1,078,031.0	7,656.0	7,784,200.0
Percent of Waters Assessed	14.2	62.2	64.7	13.2

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Summary of Water Quality Assessments for Each Waterbody Type
for Reporting Year 2008

Site-specific Targeted Monitoring Results

Louisiana Rivers and Streams 2008

Description of this table

Assessed Status	Miles

Assessed	9,421.4
Unassessed	56,872.6
Total Miles	66,294.0

Description of this table

Attainment Status	Miles

Good	1,811.2
Threatened	.0
Impaired	7,610.2
Total Miles Assessed	9,421.4

Description of this table

TMDL Development Status	Miles

All TMDLs completed	1,483.4
TMDL alternative	50.3
Non-pollutant impairment	.0
TMDL needed	6,076.5
Total Threatened and Impaired	7,610.2

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Louisiana Rivers and Streams 2008

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table

Designated Use	Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Agriculture	1,719.0	100.0	.0	.0
Drinking Water Supply	1,476.0	71.1	.0	28.9
Fish And Wildlife Propagation	9,332.0	26.8	.0	73.2
Limited Aquatic Life And Wildlife Use	82.1	23.4	.0	76.6
Outstanding Natural Resource Waters	1,577.0	63.1	.0	36.9
Oyster Propagation	470.0	56.2	.0	43.8
Primary Contact Recreation	9,040.8	81.8	.0	18.2
Secondary Contact Recreation	9,255.6	97.4	.0	2.6

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Site-specific Targeted Monitoring Results

Causes of Impairment
Louisiana Rivers and Streams 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Miles Threatened or Impaired
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	5,022.9
Mercury in Fish Tissue	Mercury	2,392.5
Turbidity	Turbidity	2,235.0
Fecal Coliform	Pathogens	1,836.0
Total Suspended Solids (TSS)	Turbidity	1,793.0
Total Dissolved Solids (TDS)	Salinity/Total Dissolved Solids/Chlorides/Sulfates	1,373.5
Nitrate/Nitrite (Nitrite + Nitrate as N)	Nutrients	1,333.0
Phosphorus, Total	Nutrients	1,269.0
Sedimentation/Siltation	Sediment	1,130.0
Carbofuran	Pesticides	930.0
Sulfates	Salinity/Total Dissolved Solids/Chlorides/Sulfates	791.0
DDT	Pesticides	749.0
pH, Low	pH/Acidity/Caustic Conditions	553.0
Lead	Metals (other than Mercury)	544.0
Non-Native Aquatic Plants	Nuisance Exotic Species	493.0
Color	Taste, Color and Odor	426.0
Toxaphene	Pesticides	420.0
Chloride	Salinity/Total Dissolved Solids/Chlorides/Sulfates	366.0
Fipronil	Pesticides	252.0
Ammonia, Total	Ammonia	120.0
Dioxin (Including 2,3,7,8-TCDD)	Dioxins	87.0
Methyl Parathion	Pesticides	43.0
Atrazine	Pesticides	43.0
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	41.0
Polycyclic Aromatic Hydrocarbons (PAHs) (Aquatic Ecosystems)	Toxic Organics	29.0
1,2-Dichloroethane	Pesticides	15.3
Benzo[a]pyrene (PAHs)	Toxic Organics	13.0
Hexachlorobutadiene	Toxic Organics	12.0
Hexachlorobenzene	Pesticides	12.0
Bromoform	Toxic Organics	12.0
1,1,1,2-Tetrachloroethane	Toxic Organics	12.0
Phenols	Toxic Organics	8.0
Methoxychlor	Pesticides	8.0
1,1,2-Trichloroethane	Toxic Organics	7.3
Chloroform	Toxic Organics	7.3
pH, High	pH/Acidity/Caustic Conditions	7.0
Chlorine	Chlorine	6.0
Copper	Metals (other than Mercury)	6.0
Oil and Grease	Oil and Grease	4.0

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Site-specific Targeted Monitoring Results

Probable Sources
Louisiana Rivers and Streams 2008

Description of this table

Probable Source	Probable Source Group	Miles Threatened or Impaired
Source Unknown	Unknown	4,085.5
Atmospheric Deposition - Toxics	Atmospheric Deposition	2,392.5
Irrigated Crop Production	Agriculture	1,863.0
Non-Irrigated Crop Production	Agriculture	1,706.0
Natural Conditions - Water Quality Standards Use Attainability Analyses Needed	Natural/Wildlife	1,638.0
Natural Sources	Natural/Wildlife	1,502.0
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Discharges/Sewage	1,086.0
Agriculture	Agriculture	720.9
Crop Production (Crop Land Or Dry Land)	Agriculture	652.0
Introduction Of Non-Native Organisms (Accidental Or Intentional)	Other	510.0
Municipal Point Source Discharges	Municipal Discharges/Sewage	488.0
Package Plant Or Other Permitted Small Flows Discharges	Municipal Discharges/Sewage	436.0
Sources Outside State Jurisdiction Or Borders	Other	409.0
Wildlife Other Than Waterfowl	Natural/Wildlife	393.0
Sanitary Sewer Overflows (Collection System Failures)	Municipal Discharges/Sewage	386.0
Naturally Occurring Organic Acids	Natural/Wildlife	327.0
Drainage/Filling/Loss Of Wetlands	Habitat Alterations (Not Directly Related To Hydromodification)	321.0
Sewage Discharges In Unsewered Areas	Municipal Discharges/Sewage	314.0
Silviculture Plantation Management	Silviculture (Forestry)	276.0
Unpermitted Discharge (Domestic Wastes)	Municipal Discharges/Sewage	268.0
Silviculture Activities	Silviculture (Forestry)	257.0
Non-Point Source	Unspecified Nonpoint Source	197.0
Managed Pasture Grazing	Agriculture	186.0
Site Clearance (Land Development Or Redevelopment)	Construction	186.0
Industrial Point Source Discharge	Industrial	184.3
Livestock (Grazing Or Feeding Operations)	Agriculture	183.0
Rural (Residential Areas)	Other	169.0
Sediment Resuspension (Clean Sediment)	Hydromodification	167.0
Flow Alterations From Water Diversions	Hydromodification	166.0
Municipal (Urbanized High Density Area)	Urban-Related Runoff/Stormwater	156.0
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	146.0
Discharges From Municipal Separate Storm Sewer Systems (Ms4)	Urban-Related Runoff/Stormwater	143.0
Habitat Modification - Other Than Hydromodification	Habitat Alterations (Not Directly Related To Hydromodification)	127.0
Littoral/Shore Area Modifications (Non-Riverine)	Habitat Alterations (Not Directly Related To Hydromodification)	127.0
Drought-Related Impacts	Natural/Wildlife	124.0
Silviculture Harvesting	Silviculture (Forestry)	121.0
Marina/Boating Sanitary On-Vessel Discharges	Recreational Boating And Marinas	90.0
Residential Districts	Urban-Related Runoff/Stormwater	86.0
Total Retention Domestic Sewage Lagoons	Municipal Discharges/Sewage	86.0
Forced Drainage Pumping	Hydromodification	83.0
Transfer Of Water From An Outside Watershed	Hydromodification	72.0
Industrial/Commercial Site Stormwater Discharge (Permitted)	Urban-Related Runoff/Stormwater	72.0
Runoff From Forest/Grassland/Parkland	Other	63.0
Changes In Tidal Circulation/Flushing	Hydromodification	59.0
Rangeland Grazing	Agriculture	58.0
Petroleum/Natural Gas Activities	Resource Extraction	52.5
Upstream Source	Other	48.0
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	42.0
Dredging (E.G., For Navigation Channels)	Hydromodification	40.0
Unspecified Domestic Waste	Municipal Discharges/Sewage	39.0
Combined Sewer Overflows	Municipal Discharges/Sewage	39.0
Unspecified Land Disturbance	Other	37.0
Industrial Land Treatment	Industrial	34.0
Mine Tailings	Resource Extraction	30.0
Waterfowl	Natural/Wildlife	22.0
Other Spill Related Impacts	Spills/Dumping	22.0
Urban Runoff/Storm Sewers	Urban-Related Runoff/Stormwater	14.0
Contaminated Sediments	Legacy/Historical Pollutants	13.0
Cercla Npl (Superfund) Sites	Legacy/Historical Pollutants	13.0
Seafood Processing Operations	Aquaculture	12.0
Dairies (Outside Milk Parlor Areas)	Agriculture	10.0
Streambank Modifications/Destabilization	Hydromodification	10.0
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	4.0

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Site-specific Targeted Monitoring Results

Louisiana Lakes, Reservoirs, and Ponds 2008

Description of this table

Assessed Status	Acres

Assessed	670,589.0
Unassessed	407,442.0
Total Acres	1,078,031.0

Description of this table

Attainment Status	Acres

Good	22,921.0
Threatened	.0
Impaired	647,668.0
Total Acres Assessed	670,589.0

Description of this table

TMDL Development Status	Acres

All TMDLs completed	308,214.0
TMDL alternative	.0
Non-pollutant impairment	.0
TMDL needed	339,454.0
Total Threatened and Impaired	647,668.0

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Louisiana Lakes, Reservoirs, and Ponds 2008

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table

Designated Use	Acres Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Agriculture	425,672.0	100.0	.0	.0
Drinking Water Supply	251,717.0	98.9	.0	1.1
Fish And Wildlife Propagation	670,589.0	3.4	.0	96.6
Primary Contact Recreation	657,168.0	94.2	.0	5.8
Secondary Contact Recreation	658,000.0	95.9	.0	4.1

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Site-specific Targeted Monitoring Results

Causes of Impairment
Louisiana Lakes, Reservoirs, and Ponds 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Acres Threatened or Impaired
Non-Native Aquatic Plants	Nuisance Exotic Species	319,163.0
Mercury in Fish Tissue	Mercury	280,403.0
Turbidity	Turbidity	256,578.0
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	194,002.0
Total Suspended Solids (TSS)	Turbidity	154,717.0
Sedimentation/Siltation	Sediment	153,472.0
Carbofuran	Pesticides	83,840.0
Sulfates	Salinity/Total Dissolved Solids/Chlorides/Sulfates	66,999.0
Total Dissolved Solids (TDS)	Salinity/Total Dissolved Solids/Chlorides/Sulfates	63,276.0
Chloride	Salinity/Total Dissolved Solids/Chlorides/Sulfates	51,840.0
Fecal Coliform	Pathogens	36,292.0
pH, High	pH/Acidity/Caustic Conditions	29,548.0
Phosphorus, Total	Nutrients	24,259.0
Nitrate/Nitrite (Nitrite + Nitrate as N)	Nutrients	24,259.0
pH, Low	pH/Acidity/Caustic Conditions	8,243.0
Ammonia, Total	Ammonia	6,099.0
Color	Taste, Color and Odor	2,690.0
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	2,260.0
Lead	Metals (other than Mercury)	1,771.0
Temperature, Water	Temperature	1,747.0
Copper	Metals (other than Mercury)	1,101.0
Arsenic	Metals (other than Mercury)	24.0
Hexachlorobutadiene	Toxic Organics	24.0
Oil and Grease	Oil and Grease	24.0
Hexachlorobenzene	Pesticides	24.0

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Site-specific Targeted Monitoring Results

Probable Sources
Louisiana Lakes, Reservoirs, and Ponds 2008

Description of this table

Probable Source	Probable Source Group	Acres Threatened or Impaired
Source Unknown	Unknown	365,906.0
Introduction Of Non-Native Organisms (Accidental Or Intentional)	Other	319,163.0
Atmospheric Deposition - Toxics	Atmospheric Deposition	280,403.0
Natural Conditions - Water Quality Standards Use Attainability Analyses Needed	Natural/Wildlife	152,226.0
Non-Irrigated Crop Production	Agriculture	134,420.0
Irrigated Crop Production	Agriculture	84,048.0
Natural Sources	Natural/Wildlife	76,963.0
Sediment Resuspension (Clean Sediment)	Hydromodification	57,530.0
Agriculture	Agriculture	44,007.0
Waterfowl	Natural/Wildlife	37,754.0
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	27,981.0
Managed Pasture Grazing	Agriculture	26,880.0
Runoff From Forest/Grassland/Parkland	Other	23,450.0
Internal Nutrient Recycling	Natural/Wildlife	16,314.0
Lake Fertilization	Other	10,272.0
Wildlife Other Than Waterfowl	Natural/Wildlife	9,280.0
Unpermitted Discharge (Domestic Wastes)	Municipal Discharges/Sewage	9,280.0
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Discharges/Sewage	9,216.0
Rural (Residential Areas)	Other	5,418.0
Naturally Occurring Organic Acids	Natural/Wildlife	4,019.0
Other Spill Related Impacts	Spills/Dumping	2,598.0
Unspecified Land Disturbance	Other	2,598.0
Industrial Point Source Discharge	Industrial	2,200.0
Package Plant Or Other Permitted Small Flows Discharges	Municipal Discharges/Sewage	2,112.0
Forced Drainage Pumping	Hydromodification	2,112.0
Silviculture Plantation Management	Silviculture (Forestry)	1,747.0
Sewage Discharges In Unsewered Areas	Municipal Discharges/Sewage	1,747.0
Crop Production (Crop Land Or Dry Land)	Agriculture	154.0
Industrial/Commercial Site Stormwater Discharge (Permitted)	Urban-Related Runoff/Stormwater	84.0
Discharges From Municipal Separate Storm Sewer Systems (Ms4)	Urban-Related Runoff/Stormwater	84.0
Sanitary Sewer Overflows (Collection System Failures)	Municipal Discharges/Sewage	24.0
Upstream Source	Other	24.0
Contaminated Sediments	Legacy/Historical Pollutants	24.0

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Site-specific Targeted Monitoring Results

Louisiana Bays and Estuaries 2008

Description of this table

Assessed Status	Square Miles

Assessed	4,953.5
Unassessed	2,702.5
Total Square Miles	7,656.0

Description of this table

Attainment Status	Square Miles

Good	2,885.0
Threatened	.0
Impaired	2,068.5
Total Square Miles Assessed	4,953.5

Description of this table

TMDL Development Status	Square Miles

All TMDLs completed	1,062.0
TMDL alternative	91.0
Non-pollutant impairment	.0
TMDL needed	915.5
Total Threatened and Impaired	2,068.5

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Louisiana Bays and Estuaries 2008

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table

Designated Use	Square Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Fish And Wildlife Propagation	4,953.5	63.2	.0	36.8
Oyster Propagation	4,268.0	80.2	.0	19.8
Primary Contact Recreation	4,953.5	99.9	.0	.1
Secondary Contact Recreation	4,953.5	100.0	.0	.0

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Site-specific Targeted Monitoring Results

Causes of Impairment
Louisiana Bays and Estuaries 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Square Miles Threatened or Impaired
Mercury in Fish Tissue	Mercury	1,657.0
Fecal Coliform	Pathogens	849.5
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	260.5
Turbidity	Turbidity	195.0
Phosphorus, Total	Nutrients	193.0
Sedimentation/Siltation	Sediment	193.0
Total Suspended Solids (TSS)	Turbidity	193.0
Nitrate/Nitrite (Nitrite + Nitrate as N)	Nutrients	193.0
Carbofuran	Pesticides	187.0
Non-Native Aquatic Plants	Nuisance Exotic Species	91.0
Ammonia, Total	Ammonia	6.0

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Site-specific Targeted Monitoring Results

Probable Sources
Louisiana Bays and Estuaries 2008

Description of this table

Probable Source	Probable Source Group	Square Miles Threatened or Impaired
Atmospheric Deposition - Toxics	Atmospheric Deposition	1,657.0
Source Unknown	Unknown	1,613.0
Natural Sources	Natural/Wildlife	583.0
Petroleum/Natural Gas Production Activities (Permitted)	Industrial	581.0
Package Plant Or Other Permitted Small Flows Discharges	Municipal Discharges/Sewage	581.0
Irrigated Crop Production	Agriculture	193.0
Non-Irrigated Crop Production	Agriculture	193.0
Introduction Of Non-Native Organisms (Accidental Or Intentional)	Other	91.0
Unspecified Domestic Waste	Municipal Discharges/Sewage	64.0
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	64.0
Changes In Ordinary Stratification And Bottom Water Hypoxia/Anoxia	Natural/Wildlife	64.0
Wildlife Other Than Waterfowl	Natural/Wildlife	55.0
Marina/Boating Sanitary On-Vessel Discharges	Recreational Boating And Marinas	55.0
Upstream Source	Other	44.0
Urban Runoff/Storm Sewers	Urban-Related Runoff/Stormwater	3.5
Discharges From Municipal Separate Storm Sewer Systems (Ms4)	Urban-Related Runoff/Stormwater	3.5
Sewage Discharges In Unsewered Areas	Municipal Discharges/Sewage	3.5
Sediment Resuspension (Clean Sediment)	Hydromodification	2.0
Sanitary Sewer Overflows (Collection System Failures)	Municipal Discharges/Sewage	2.0

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Site-specific Targeted Monitoring Results

Louisiana Wetlands 2008

Description of this table

Assessed Status	Acres

Assessed	1,029,760.0
Unassessed	6,754,440.0
Total Acres	7,784,200.0

Description of this table

Attainment Status	Acres

Good	627,200.0
Threatened	.0
Impaired	402,560.0
Total Acres Assessed	1,029,760.0

Description of this table

TMDL Development Status	Acres

All TMDLs completed	.0
TMDL alternative	.0
Non-pollutant impairment	.0
TMDL needed	402,560.0
Total Threatened and Impaired	402,560.0

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Louisiana Wetlands 2008

* Waters assessed for more than one designated use are included in multiple designated use groups below.

Description of this table

Designated Use	Acres Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
					% Threatened
					% Impaired
Drinking Water Supply	464,000.0	100.0	.0	.0
Fish And Wildlife Propagation	1,025,280.0	60.7	.0	39.3
Primary Contact Recreation	1,025,280.0	99.3	.0	.7
Secondary Contact Recreation	1,029,760.0	100.0	.0	.0

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Site-specific Targeted Monitoring Results

Causes of Impairment
Louisiana Wetlands 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Acres Threatened or Impaired
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	394,880.0
Mercury in Fish Tissue	Mercury	199,040.0
Total Dissolved Solids (TDS)	Salinity/Total Dissolved Solids/Chlorides/Sulfates	7,680.0
Chloride	Salinity/Total Dissolved Solids/Chlorides/Sulfates	7,680.0
Temperature, Water	Temperature	7,680.0
Sulfates	Salinity/Total Dissolved Solids/Chlorides/Sulfates	7,680.0

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Site-specific Targeted Monitoring Results

Probable Sources
Louisiana Wetlands 2008

Description of this table

Probable Source	Probable Source Group	Acres Threatened or Impaired
Atmospheric Deposition - Toxics	Atmospheric Deposition	199,040.0
Source Unknown	Unknown	199,040.0
Non-Irrigated Crop Production	Agriculture	195,840.0
Petroleum/Natural Gas Production Activities (Permitted)	Industrial	195,840.0
Drainage/Filling/Loss Of Wetlands	Habitat Alterations (Not Directly Related To Hydromodification)	7,680.0
Littoral/Shore Area Modifications (Non-Riverine)	Habitat Alterations (Not Directly Related To Hydromodification)	7,680.0
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	7,680.0
Habitat Modification - Other Than Hydromodification	Habitat Alterations (Not Directly Related To Hydromodification)	7,680.0

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Louisiana Causes of Impairment for Reporting Year 2008

Description of this table

Cause of Impairment Group	Size of Assessed Waters with Listed Causes of Impairment
NOTE: Click on the underlined Cause of Impairment Group to see a list of specific state causes of impairment making up the Cause of Impairment Group. See also Pollution categories summary document (PDF) (20 pp, 557K, About PDF) for brief, non-technical descriptions of general cause categories.
Cause of Impairment Group	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)	Wetlands (Acres)
Ammonia	120.0	6,099.0	6.0
Chlorine	6.0
Dioxins	87.0
Mercury	2,392.5	280,403.0	1,657.0	199,040.0
Metals (other than Mercury)	550.0	2,872.0
Nuisance Exotic Species	493.0	319,163.0	91.0
Nutrients	1,333.0	24,259.0	193.0
Oil and Grease	4.0	24.0
Organic Enrichment/Oxygen Depletion	5,022.9	194,002.0	260.5	394,880.0
Pathogens	1,836.0	36,292.0	849.5
Pesticides	1,355.3	83,864.0	187.0
pH/Acidity/Caustic Conditions	560.0	37,791.0
Polychlorinated Biphenyls (PCBs)	41.0	2,260.0
Salinity/Total Dissolved Solids/Chlorides/Sulfates	1,821.5	78,435.0		7,680.0
Sediment	1,130.0	153,472.0	193.0
Taste, Color and Odor	426.0	2,690.0
Temperature		1,747.0		7,680.0
Toxic Organics	61.3	24.0
Turbidity	2,289.0	256,626.0	195.0

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Louisiana Probable Sources Contributing to Impairments
for Reporting Year 2008

Description of this table

Probable Source Group	Size of Assessed Waters with Probable Sources of Impairments
NOTE: Click on the underlined Probable Source Group to see a list of specific state Probable Sources making up the Probable Source Group.
Probable Source Group	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)	Wetlands (Acres)
Agriculture	2,882.9	164,347.0	193.0	195,840.0
Aquaculture	12.0
Atmospheric Deposition	2,392.5	280,403.0	1,657.0	199,040.0
Construction	186.0
Habitat Alterations (Not Directly Related To Hydromodification)	321.0			7,680.0
Hydromodification	635.0	87,623.0	2.0	7,680.0
Industrial	218.3	2,200.0	581.0	195,840.0
Legacy/Historical Pollutants	13.0	24.0
Municipal Discharges/Sewage	2,163.0	20,267.0	648.5
Natural/Wildlife	3,033.0	276,348.0	702.0
Other	1,236.0	327,203.0	135.0
Recreational Boating And Marinas	90.0		55.0
Resource Extraction	82.5
Silviculture (Forestry)	654.0	1,747.0
Spills/Dumping	22.0	2,598.0
Unknown	4,085.5	365,906.0	1,613.0	199,040.0
Unspecified Nonpoint Source	197.0
Urban-Related Runoff/Stormwater	499.0	84.0	67.5

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Louisiana TMDL Alternatives by Cause of Impairment 2008

Description of this table

Cause of Impairment	Number of TMDL Alternatives	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)
NOTE: Click on the underlined "Number of TMDL Alternatives by Cause of Impairment " value to see a listing of those Causes of Impairment.
Non-Native Aquatic Plants	40	487	311,438	91
Polychlorinated Biphenyls (PCBs)	3		2,260
Benzo[a]pyrene (PAHs)	2	13
Oil and Grease	2	4	24
1,1,2-Trichloroethane	1	7
1,2-Dichloroethane	1	7
Arsenic	1		24
Chloroform	1	7
Hexachlorobenzene	1		24
Hexachlorobutadiene	1		24
Lead	1		24

Total: 54 TMDL Alternatives

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