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Connecticut Assessment Summary for Reporting Year 2008

Description of this table

	Size of Water
	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)
Good Waters	1,224.9	20,654.5	192.3
Previously impaired waters       now attaining all uses	16.0
Threatened Waters
TMDL completed
TMDL alternative
Non-pollutant impairment
TMDL needed
Impaired Waters	874.1	6,220.5	419.6
TMDL completed	76.0	256.7	173.8
TMDL alternative	23.7	339.3
Non-pollutant impairment	29.7	392.1
TMDL needed	744.7	5,232.4	245.7
New TMDLs completed	1.8	.0	.0
Remaining TMDLs needed	742.9	5,232.4	245.7
Total Assessed Waters	2,099.1	26,874.9	611.9
Total Waters	5,830.0	64,973.0	613.3
Percent of Waters Assessed	36.0	41.4	99.8

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

Connecticut Assessed Waters
Summary of Water Quality Attainment for Rivers and Streams
Reporting Year 2008

Description of this table Assessed Status Miles Assessed 2,099.1 Unassessed 3,730.9 Total Miles 5,830.0

Description of this table Attainment Status Miles Good 1,224.9 Threatened .0 Impaired 874.1 Total Miles Assessed 2,099.1

Description of this table TMDL Development Status Miles All TMDLs completed 77.9 TMDL alternative 23.7 Non-pollutant impairment 29.7 TMDL needed 742.9 Total Threatened and Impaired 874.1

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Connecticut Assessed Waters
Designated Use Support for Rivers and Streams
Reporting Year 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
Existing Or Proposed Drinking Water	1.2	.0	.0	100.0
Fish Consumption	2,097.2	93.8	.0	6.2
Habitat For Fish, Other Aquatic Life And Wildlife	1,198.9	67.0	.0	33.0
Recreation	812.7	14.0	.0	86.0

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Connecticut Causes of Impairment
for Threatened and Impaired Rivers and Streams
Reporting Year 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Miles Threatened or Impaired
Escherichia Coli (E. Coli)	Pathogens	691.4
Cause Unknown	Cause Unknown	341.2
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	127.8
Enterococcus Bacteria	Pathogens	59.0
Other Flow Regime Alterations	Flow Alteration(s)	33.5
Physical Substrate Habitat Alterations	Habitat Alterations	32.3
Sedimentation/Siltation	Sediment	5.6
Whole Effluent Toxicity (WET)	Total Toxics	5.4
Iron	Metals (other than Mercury)	5.3
Alterations in Wetland Habitats	Habitat Alterations	4.5
Chlorine	Chlorine	4.4
Copper	Metals (other than Mercury)	3.8
Mercury	Mercury	3.8
Zinc	Metals (other than Mercury)	3.3
Propylene Glycol	Toxic Organics	3.1
Ethylene Glycol	Toxic Organics	3.1
Lead	Metals (other than Mercury)	2.7
Ammonia, Un-ionized	Ammonia	2.2
Temperature, Water	Temperature	1.8
Sodium	Salinity/Total Dissolved Solids/Chlorides/Sulfates	1.4
Turbidity	Turbidity	1.4
Uranium	Radiation	.7
Cobalt	Metals (other than Mercury)	.7
Nutrient/Eutrophication Biological Indicators	Nutrients	.6
Dissolved Oxygen Saturation	Organic Enrichment/Oxygen Depletion	.6
Organic Enrichment (Sewage) Biological Indicators	Organic Enrichment/Oxygen Depletion	.6
Sulfates	Salinity/Total Dissolved Solids/Chlorides/Sulfates	.1
Diesel Fuel	Oil and Grease	.1

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Connecticut Probable Sources of Impairments
for Threatened and Impaired Rivers and Streams
Reporting Year 2008

Description of this table

Probable Source	Probable Source Group	Miles Threatened or Impaired
Source Unknown	Unknown	766.0
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	222.2
Municipal Point Source Discharges	Municipal Dishcarges/Sewage	130.5
Sources Outside State Jurisdiction Or Borders	Other	106.6
Industrial Point Source Discharge	Industrial	105.3
Combined Sewer Overflows	Municipal Dishcarges/Sewage	78.6
Illicit Connections/Hook-Ups To Storm Sewers	Municipal Dishcarges/Sewage	52.0
Landfills	Land Application/Waste Sites/Tanks	49.5
Contaminated Sediments	Legacy/Historical Pollutants	48.8
Sanitary Sewer Overflows (Collection System Failures)	Municipal Dishcarges/Sewage	46.5
Agriculture	Agriculture	43.1
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	42.4
Upstream Impoundments (E.G., Pl-566 Nrcs Structures)	Hydromodification	41.1
Channelization	Hydromodification	39.4
Site Clearance (Land Development Or Redevelopment)	Construction	37.9
Baseflow Depletion From Groundwater Withdrawals	Hydromodification	32.3
Above Ground Storage Tank Leaks (Tank Farms)	Spills/Dumping	25.5
Flow Alterations From Water Diversions	Hydromodification	23.7
Golf Courses	Recreation And Tourism (Non-Boating)	22.2
Dredge Mining	Resource Extraction	15.7
Loss Of Riparian Habitat	Habitat Alterations (Not Directly Related To Hydromodification)	15.2
Animal Feeding Operations (Nps)	Agriculture	11.9
Livestock (Grazing Or Feeding Operations)	Agriculture	10.4
Waterfowl	Natural/Wildlife	8.9
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Dishcarges/Sewage	7.2
Surface Mining	Resource Extraction	4.9
Habitat Modification - Other Than Hydromodification	Habitat Alterations (Not Directly Related To Hydromodification)	4.6
Irrigated Crop Production	Agriculture	4.2
Post-Development Erosion And Sedimentation	Hydromodification	4.0
Industrial Land Treatment	Industrial	3.8
Natural Sources	Natural/Wildlife	3.2
Airports	Industrial	3.1
Accidental Release/Spill	Spills/Dumping	2.9
Non-Point Source	Unspecified Nonpoint Source	2.1
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	2.0
Streambank Modifications/Destabilization	Hydromodification	1.7
Drainage/Filling/Loss Of Wetlands	Habitat Alterations (Not Directly Related To Hydromodification)	1.5
Managed Pasture Grazing	Agriculture	1.2
Discharges From Biosolids (Sludge) Storage, Application Or Disposal	Land Application/Waste Sites/Tanks	.6
Inappropriate Waste Disposal	Spills/Dumping	.4
Non-Irrigated Crop Production	Agriculture	.2
Leaking Underground Storage Tanks	Land Application/Waste Sites/Tanks	.1

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Connecticut Assessed Waters
Summary of Water Quality Attainment for Lakes, Reservoirs, and Ponds
Reporting Year 2008

Description of this table Assessed Status Acres Assessed 26,874.9 Unassessed 38,098.1 Total Acres 64,973.0

Description of this table Attainment Status Acres Good 20,654.5 Threatened .0 Impaired 6,220.5 Total Acres Assessed 26,874.9

Description of this table TMDL Development Status Acres All TMDLs completed 256.7 TMDL alternative 339.3 Non-pollutant impairment 392.1 TMDL needed 5,232.4 Total Threatened and Impaired 6,220.5

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Connecticut Assessed Waters
Designated Use Support for Lakes, Reservoirs, and Ponds
Reporting Year 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
Existing Or Proposed Drinking Water	1,190.3	100.0	.0	.0
Fish Consumption	26,864.2	85.9	.0	14.1
Habitat For Fish, Other Aquatic Life And Wildlife	26,618.9	95.6	.0	4.4
Recreation	24,526.2	80.5	.0	19.5

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Connecticut Causes of Impairment
for Threatened and Impaired Lakes, Reservoirs, and Ponds
Reporting Year 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Acres Threatened or Impaired
Nutrient/Eutrophication Biological Indicators	Nutrients	3,520.0
Excess Algal Growth	Algal Growth	3,353.4
Chlorophyll-A	Algal Growth	3,213.6
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	3,068.6
Taste and Odor	Taste, Color and Odor	1,594.9
Debris/Floatables/Trash	Trash	1,594.9
Escherichia Coli (E. Coli)	Pathogens	1,146.1
Mercury	Mercury	810.0
Non-Native Aquatic Plants	Nuisance Exotic Species	389.4
Other Flow Regime Alterations	Flow Alteration(s)	214.4
Sedimentation/Siltation	Sediment	195.5
Turbidity	Turbidity	194.5
Phosphorus, Total	Nutrients	112.8
Dissolved Oxygen Saturation	Organic Enrichment/Oxygen Depletion	110.7
Alterations in Wetland Habitats	Habitat Alterations	95.6
Enterococcus Bacteria	Pathogens	70.5
Chlordane	Pesticides	53.9
Lead	Metals (other than Mercury)	24.1
Total Suspended Solids (TSS)	Turbidity	9.4
Cadmium	Metals (other than Mercury)	5.0
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	4.0
Copper	Metals (other than Mercury)	.6
Ammonia, Un-ionized	Ammonia	.6
Organic Enrichment (Sewage) Biological Indicators	Organic Enrichment/Oxygen Depletion	.6

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Connecticut Probable Sources of Impairments
for Threatened and Impaired Lakes, Reservoirs, and Ponds
Reporting Year 2008

Description of this table

Probable Source	Probable Source Group	Acres Threatened or Impaired
Contaminated Sediments	Legacy/Historical Pollutants	3,098.3
Sources Outside State Jurisdiction Or Borders	Other	3,050.2
Industrial Point Source Discharge	Industrial	3,018.8
Source Unknown	Unknown	2,891.7
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	2,211.3
Agriculture	Agriculture	1,971.9
Municipal Point Source Discharges	Municipal Dishcarges/Sewage	1,854.7
Non-Point Source	Unspecified Nonpoint Source	1,782.4
Atmospheric Deposition - Toxics	Atmospheric Deposition	625.3
Internal Nutrient Recycling	Natural/Wildlife	508.4
Waterfowl	Natural/Wildlife	443.9
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Dishcarges/Sewage	279.0
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	216.0
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	214.4
Post-Development Erosion And Sedimentation	Hydromodification	204.8
Sediment Resuspension (Clean Sediment)	Hydromodification	140.6
Habitat Modification - Other Than Hydromodification	Habitat Alterations (Not Directly Related To Hydromodification)	95.6
Above Ground Storage Tank Leaks (Tank Farms)	Spills/Dumping	70.5
Natural Sources	Natural/Wildlife	56.8
Surface Mining	Resource Extraction	44.5
Other Spill Related Impacts	Spills/Dumping	29.6
Streambank Modifications/Destabilization	Hydromodification	9.4
Combined Sewer Overflows	Municipal Dishcarges/Sewage	2.7
Discharges From Biosolids (Sludge) Storage, Application Or Disposal	Land Application/Waste Sites/Tanks	.6
Landfills	Land Application/Waste Sites/Tanks	.6

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Connecticut Assessed Waters
Summary of Water Quality Attainment for Bays and Estuaries
Reporting Year 2008

Description of this table Assessed Status Square Miles Assessed 611.9 Unassessed 1.5 Total Square Miles 613.3

Description of this table Attainment Status Square Miles Good 192.3 Threatened .0 Impaired 419.6 Total Square Miles Assessed 611.9

Description of this table TMDL Development Status Square Miles All TMDLs completed 173.8 TMDL alternative .0 Non-pollutant impairment .0 TMDL needed 245.7 Total Threatened and Impaired 419.6

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Connecticut Assessed Waters
Designated Use Support for Bays and Estuaries
Reporting Year 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
Commercial Shellfish Harvesting Where Authorized	65.1	60.1	.0	39.9
Fish Consumption	611.9	98.6	.0	1.4
Habitat For Marine Fish, Other Aquatic Life And Wildlife	548.5	42.7	.0	57.3
Recreation	40.2	71.1	.0	28.9
Shellfish Harvesting For Direct Consumption Where Authorized	246.4	17.3	.0	82.7

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Connecticut Causes of Impairment
for Threatened and Impaired Bays and Estuaries
Reporting Year 2008

Description of this table

Cause of Impairment	Cause of Impairment Group	Square Miles Threatened or Impaired
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	304.0
Dissolved Oxygen Saturation	Organic Enrichment/Oxygen Depletion	304.0
Nutrient/Eutrophication Biological Indicators	Nutrients	290.2
Nitrogen, Total	Nutrients	278.0
Fecal Coliform	Pathogens	229.8
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	17.8
Estuarine Bioassessments	Cause Unknown - Impaired Biota	13.7
Enterococcus Bacteria	Pathogens	11.6
Oil and Grease	Oil and Grease	9.5
Cause Unknown	Cause Unknown	8.8
Organic Enrichment (Sewage) Biological Indicators	Organic Enrichment/Oxygen Depletion	2.0
Polycyclic Aromatic Hydrocarbons (PAHs) (Aquatic Ecosystems)	Toxic Organics	1.9
Zinc	Metals (other than Mercury)	1.5
Copper	Metals (other than Mercury)	1.5
Dioxin (Including 2,3,7,8-TCDD)	Dioxins	1.4
Lead	Metals (other than Mercury)	1.0
Mercury	Mercury	.9
Alterations in Wetland Habitats	Habitat Alterations	.4
Gold	Metals (other than Mercury)	.2
Silver	Metals (other than Mercury)	.2
Escherichia Coli (E. Coli)	Pathogens	.0

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Connecticut Probable Sources of Impairments
for Threatened and Impaired Bays and Estuaries
Reporting Year 2008

Description of this table

Probable Source	Probable Source Group	Square Miles Threatened or Impaired
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	417.9
Residential Districts	Urban-Related Runoff/Stormwater	416.6
Non-Point Source	Unspecified Nonpoint Source	378.9
Atmospheric Deposition - Nitrogen	Atmospheric Deposition	291.2
Municipal Point Source Discharges	Municipal Dishcarges/Sewage	290.2
Industrial Point Source Discharge	Industrial	279.0
Marina/Boating Sanitary On-Vessel Discharges	Recreational Boating And Marinas	244.0
Combined Sewer Overflows	Municipal Dishcarges/Sewage	228.2
Waterfowl	Natural/Wildlife	221.2
On-Site Treatment Systems (Septic Systems And Similar Decentralized Systems)	Municipal Dishcarges/Sewage	123.3
Wet Weather Discharges (Point Source And Combination Of Stormwater, Sso Or Cso)	Municipal Dishcarges/Sewage	89.4
Source Unknown	Unknown	39.4
Natural Sources	Natural/Wildlife	14.6
Contaminated Sediments	Legacy/Historical Pollutants	12.1
Landfills	Land Application/Waste Sites/Tanks	9.8
Illicit Connections/Hook-Ups To Storm Sewers	Municipal Dishcarges/Sewage	6.1
Sources Outside State Jurisdiction Or Borders	Other	4.0
Sanitary Sewer Overflows (Collection System Failures)	Municipal Dishcarges/Sewage	3.9
Agriculture	Agriculture	1.6
Industrial/Commercial Site Stormwater Discharge (Permitted)	Urban-Related Runoff/Stormwater	1.5
Airports	Industrial	1.4
Upstream Impoundments (E.G., Pl-566 Nrcs Structures)	Hydromodification	.8
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	.6
Other Spill Related Impacts	Spills/Dumping	.4
Dredge Mining	Resource Extraction	.4
Non-Irrigated Crop Production	Agriculture	.3
Flow Alterations From Water Diversions	Hydromodification	.1
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	.1

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Connecticut Causes of Impairment for Reporting Year 2008

Description of this table

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.
Cause of Impairment Group	Size of Assessed Waters with Listed Causes of Impairment
	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)
Algal Growth		3,353.4
Ammonia	2.2	.6
Cause Unknown	341.2		8.8
Cause Unknown - Impaired Biota			13.7
Chlorine	4.4
Dioxins			1.4
Flow Alteration(s)	33.5	214.4
Habitat Alterations	36.8	95.6	.4
Mercury	3.8	810.0	.9
Metals (other than Mercury)	13.1	24.1	2.6
Nuisance Exotic Species		389.4
Nutrients	.6	3,632.8	292.2
Oil and Grease	.1		9.5
Organic Enrichment/Oxygen Depletion	.6	114.8	304.0
Pathogens	696.5	1,216.6	229.8
Pesticides		53.9
Polychlorinated Biphenyls (PCBs)	127.8	3,068.6	17.8
Radiation	.7
Salinity/Total Dissolved Solids/Chlorides/Sulfates	1.5
Sediment	5.6	195.5
Taste, Color and Odor		1,594.9
Temperature	1.8
Total Toxics	5.4
Toxic Organics	3.1		1.9
Trash		1,594.9
Turbidity	1.4	194.5

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Connecticut Probable Sources Contributing to Impairments
for Reporting Year 2008

Description of this table

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	Size of Assessed Waters with Probable Sources of Impairments
	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)
Agriculture	57.3	1,971.9	1.9
Atmospheric Deposition		625.3	291.2
Construction	37.9
Habitat Alterations (Not Directly Related To Hydromodification)	21.3	95.6
Hydromodification	111.1	559.8	.8
Industrial	109.3	3,018.8	279.0
Land Application/Waste Sites/Tanks	49.6	.6	9.8
Legacy/Historical Pollutants	48.8	3,098.3	12.1
Municipal Dishcarges/Sewage	223.1	2,136.4	375.6
Natural/Wildlife	8.9	1,009.0	232.5
Other	106.6	3,050.2	4.0
Recreation And Tourism (Non-Boating)	22.2
Recreational Boating And Marinas			244.0
Resource Extraction	20.6	44.5	.4
Spills/Dumping	28.7	100.1	.4
Unknown	766.0	2,891.7	39.4
Unspecified Nonpoint Source	2.1	1,782.4	378.9
Urban-Related Runoff/Stormwater	224.1	2,211.3	419.0

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Connecticut TMDL Alternatives by Cause of Impairment 2008

Description of this table

NOTE: Click on the underlined "Number of TMDL Alternatives by Cause of Impairment " value to see a listing of those Causes of Impairment.
Cause of Impairment	Number of TMDL Alternatives	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)
Polychlorinated Biphenyls (PCBs)	10	49	2,861
Chlorine	1	1
Cobalt	1	1
Diesel Fuel	1	0
Lead	1			0
Mercury	1	0
Sulfates	1	0
Uranium	1	1

Total: 17 TMDL Alternatives

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Connecticut Previously Impaired Waters Now Attaining All Uses

Description of this table

NOTE: Click on the underlined "Number of Waters Attaining" value for a detailed list of those waters now attaining all uses.
Cycle Attaining	Number of Waters Attaining	Number of Causes of Impairment Addressed
2004	6	8
2006	3	3

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Connecticut Causes of Impairment for 303(d) Listed Waters

Description of this table

NOTE: Click on a cause of impairment (e.g. pathogens) to see the specific state-reported causes that are grouped to make up this category. Click on the "Number of Causes of Impairment Reported" to see a list of waters with that cause of impairment.
Cause of Impairment Group Name	Number of Causes of Impairment Reported
Pathogens	340
Cause Unknown	113
Organic Enrichment/Oxygen Depletion	67
Nutrients	44
Polychlorinated Biphenyls (PCBs)	31
Metals (other than Mercury)	20
Algal Growth	19
Mercury	11
Oil and Grease	9
Cause Unknown - Impaired Biota	8
Sediment	5
Turbidity	4
Dioxins	2
Pesticides	2
Ammonia	2
Toxic Organics	2
Chlorine	1
Taste, Color and Odor	1
Other Cause	1
Salinity/Total Dissolved Solids/Chlorides/Sulfates	1
Total Toxics	1

Total: 684 Causes of Impairment

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Connecticut Cumulative TMDLs by Pollutant

This chart includes TMDLs since October 1, 1995.

Description of this table

NOTE: Click on the underlined "Pollutant" value to see associated listed waters for which a TMDL was developed. Click on the underlined "Number of TMDLs" value to see a listing of those TMDLs for the pollutant.
Pollutant	Number of TMDLs	Number of Causes of Impairment Addressed
Escherichia Coli (E. Coli)	63	64
Copper	6	6
Zinc	5	5
Chlorine	4	4
Algal Growth	3	3
Ammonia	3	3
Lead	3	3
1,2-Propanediol	2	2
Ethylene Glycol	2	2
Fecal Coliform	2	2
Nitrogen, Total	2	2
Nutrients	2	2
Organic Enrichment/Low Dissolved Oxygen	2	2
Phosphorus, Total	2	2
Pollutants in Urban Stormwater	2	2
Turbidity	2	2
Algal Growth/Chlorophyll A	1	1
Chlorophyll-A	1	1
Nitrogen	1	1
Toxicity	1	1

Total: 109 TMDLs; 110 Causes of Impairment Addressed

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Connecticut Cumulative Number of TMDLs

EPA Fiscal Year starts October 1 and ends September 30.

Description of this table

NOTE: Click on the underlined "Number of TMDLs Completed" value for a detailed list of the TMDLs for the fiscal year.
Fiscal Year	Number of TMDLs	Number of Causes of Impairment Addressed
2000	11	11
2001	9	9
2002	7	7
2004	3	3
2005	30	30
2006	16	16
2007	7	7
2008	26	27

Total: 109 TMDLs; 110 Causes of Impairment Addressed

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