Connecticut Water Quality Assessment Report

Assessed Waters of Connecticut by Watershed

Search for a waterbody within Connecticut

Features

Site-specific Targeted Monitoring Summary Results

Connecticut (2006)

	Rivers and Streams (Miles)	Lakes, Reservoirs, and Ponds (Acres)	Bays and Estuaries (Square Miles)
	Size of Water
Good Waters	1,321.9	20,654.5	236.8
Previously impaired waters now attaining all uses	63.0		4.3
Threatened Waters
TMDL completed
TMDL alternative
Non-pollutant impairment
TMDL needed
Impaired Waters	638.2	6,220.5	375.8
TMDL completed	77.1	246.7	209.4
TMDL alternative	50.0	339.3
Non-pollutant impairment	29.7	392.1
TMDL needed	481.5	5,242.4	166.5
New TMDLs completed	54.8	1,057.3	.0
Remaining TMDLs needed	426.7	4,185.0	166.5

Total Assessed Waters	1,960.1	26,874.9	612.6
Total Waters	5,830.0	64,973.0	613.3
Percent of Waters Assessed	33.6	41.4	99.9

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Summary of Water Quality Assessments for Each Waterbody Type
for Reporting Year 2006

Site-specific Targeted Monitoring Results

Connecticut Rivers and Streams 2006

Description of this table

Assessed Status	Miles

Assessed	1,960.1
Unassessed	3,869.9
Total Miles	5,830.0

Description of this table

Attainment Status	Miles

Good	1,321.9
Threatened	.0
Impaired	638.2
Total Miles Assessed	1,960.1

Description of this table

TMDL Development Status	Miles

All TMDLs completed	131.8
TMDL alternative	50.0
Non-pollutant impairment	29.7
TMDL needed	426.7
Total Threatened and Impaired	638.2

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Connecticut Rivers and Streams 2006

* 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	181.6	99.3	.0	.7
Fish Consumption	1,958.3	93.4	.0	6.6
Habitat For Fish, Other Aquatic Life And Wildlife	950.1	61.5	.0	38.5
Recreation	553.1	24.8	.0	75.2

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Site-specific Targeted Monitoring Results

Causes of Impairment
Connecticut Rivers and Streams 2006

Description of this table

Cause of Impairment	Cause of Impairment Group	Miles Threatened or Impaired
Escherichia Coli (E. Coli)	Pathogens	403.0
Cause Unknown	Cause Unknown	314.5
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	127.8
Enterococcus Bacteria	Pathogens	63.9
Physical Substrate Habitat Alterations	Habitat Alterations	36.1
Other Flow Regime Alterations	Flow Alteration(s)	33.8
Chlorine	Chlorine	6.1
Sedimentation/Siltation	Sediment	5.6
Copper	Metals (other than Mercury)	5.5
Whole Effluent Toxicity (WET)	Total Toxics	5.4
Iron	Metals (other than Mercury)	5.3
Zinc	Metals (other than Mercury)	5.0
Alterations in Wetland Habitats	Habitat Alterations	4.5
Lead	Metals (other than Mercury)	4.4
Ammonia, Un-ionized	Ammonia	3.9
Mercury	Mercury	3.8
Propylene Glycol	Toxic Organics	3.1
Ethylene Glycol	Toxic Organics	3.1
Temperature, Water	Temperature	1.8
Sodium	Salinity/Total Dissolved Solids/Chlorides/Sulfates	1.4
Turbidity	Turbidity	1.4
Cobalt	Metals (other than Mercury)	.7
Uranium	Radiation	.7
Dissolved Oxygen Saturation	Organic Enrichment/Oxygen Depletion	.6
Organic Enrichment (Sewage) Biological Indicators	Organic Enrichment/Oxygen Depletion	.6
Nutrient/Eutrophication Biological Indicators	Nutrients	.6
Sulfates	Salinity/Total Dissolved Solids/Chlorides/Sulfates	.1
Diesel Fuel	Oil and Grease	.1

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Site-specific Targeted Monitoring Results

Probable Sources
Connecticut Rivers and Streams 2006

Description of this table

Probable Source	Probable Source Group	Miles Threatened or Impaired
Source Unknown	Unknown	392.9
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	214.5
Municipal Point Source Discharges	Municipal Discharges/Sewage	132.2
Sources Outside State Juristiction Or Borders	Other	106.6
Industrial Point Source Discharge	Industrial	105.3
Combined Sewer Overflows	Municipal Discharges/Sewage	79.9
Landfills	Land Application/Waste Sites/Tanks	49.5
Contaminated Sediments	Legacy/Historical Pollutants	48.8
Sanitary Sewer Overflows (Collection System Failures)	Municipal Discharges/Sewage	46.5
Impacts From Hydrostructure Flow Regulation/Modification	Hydromodification	42.4
Upstream Impoundments (E.G., Pl-566 Nrcs Structures)	Hydromodification	41.4
Channelization	Hydromodification	39.4
Site Clearance (Land Development Or Redevelopment)	Construction	37.9
Baseflow Depletion From Groundwater Withdrawals	Hydromodification	32.3
Agriculture	Agriculture	29.1
Above Ground Storage Tank Leaks (Tank Farms)	Spills/Dumping	25.5
Flow Alterations From Water Diversions	Hydromodification	24.0
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	13.1
Livestock (Grazing Or Feeding Operations)	Agriculture	10.4
Waterfowl	Natural/Wildlife	8.9
Surface Mining	Resource Extraction	8.4
On-Site Treatment Systems (Septic Systems And Similar Decencentralized Systems)	Municipal Discharges/Sewage	7.2
Illicit Connections/Hook-Ups To Storm Sewers	Municipal Discharges/Sewage	4.8
Irrigated Crop Production	Agriculture	4.2
Post-Development Erosion And Sedimentation	Hydromodification	4.0
Habitat Modification - Other Than Hydromodification	Habitat Alterations (Not Directly Related To 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/Destablization	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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Site-specific Targeted Monitoring Results

Connecticut Lakes, Reservoirs, and Ponds 2006

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	1,304.1
TMDL alternative	339.3
Non-pollutant impairment	392.1
TMDL needed	4,185.0
Total Threatened and Impaired	6,220.5

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Connecticut Lakes, Reservoirs, and Ponds 2006

* 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	94.4	.0	5.6
Recreation	24,526.2	80.5	.0	19.5

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Site-specific Targeted Monitoring Results

Causes of Impairment
Connecticut Lakes, Reservoirs, and Ponds 2006

Description of this table

Cause of Impairment	Cause of Impairment Group	Acres Threatened or Impaired
Nutrient/Eutrophication Biological Indicators	Nutrients	3,855.2
Excess Algal Growth	Algal Growth	3,688.7
Chlorophyll-A	Algal Growth	3,552.9
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
Dissolved Oxygen Saturation	Organic Enrichment/Oxygen Depletion	450.0
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
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
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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Site-specific Targeted Monitoring Results

Probable Sources
Connecticut Lakes, Reservoirs, and Ponds 2006

Description of this table

Probable Source	Probable Source Group	Acres Threatened or Impaired
Contaminated Sediments	Legacy/Historical Pollutants	3,098.3
Sources Outside State Juristiction 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	2,207.3
Agriculture	Agriculture	1,971.9
Municipal Point Source Discharges	Municipal Discharges/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
Upstream Impoundments (E.G., Pl-566 Nrcs Structures)	Hydromodification	339.3
On-Site Treatment Systems (Septic Systems And Similar Decencentralized Systems)	Municipal Discharges/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/Destablization	Hydromodification	9.4
Combined Sewer Overflows	Municipal Discharges/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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Site-specific Targeted Monitoring Results

Connecticut Bays and Estuaries 2006

Description of this table

Assessed Status	Square Miles

Assessed	612.6
Unassessed	.7
Total Square Miles	613.3

Description of this table

Attainment Status	Square Miles

Good	236.8
Threatened	.0
Impaired	375.8
Total Square Miles Assessed	612.6

Description of this table

TMDL Development Status	Square Miles

All TMDLs completed	209.4
TMDL alternative	.0
Non-pollutant impairment	.0
TMDL needed	166.5
Total Threatened and Impaired	375.8

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Connecticut Bays and Estuaries 2006

* 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	67.0	59.9	.0	40.1
Fish Consumption	612.6	98.9	.0	1.1
Habitat For Marine Fish, Other Aquatic Life And Wildlife	550.9	47.3	.0	52.7
Recreation	154.0	87.1	.0	12.9
Shellfish Harvesting For Direct Consumption Where Authorized	246.8	50.9	.0	49.1

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Site-specific Targeted Monitoring Results

Causes of Impairment
Connecticut Bays and Estuaries 2006

Description of this table

Cause of Impairment	Cause of Impairment Group	Square Miles Threatened or Impaired
Dissolved Oxygen Saturation	Organic Enrichment/Oxygen Depletion	285.9
Dissolved Oxygen	Organic Enrichment/Oxygen Depletion	285.9
Nutrient/Eutrophication Biological Indicators	Nutrients	276.2
Nitrogen, Total	Nutrients	261.4
Fecal Coliform	Pathogens	145.9
Enterococcus Bacteria	Pathogens	19.8
Polychlorinated Biphenyls (PCBs)	Polychlorinated Biphenyls (PCBs)	18.0
Estuarine Bioassessments	Cause Unknown - Impaired Biota	11.6
Oil and Grease	Oil and Grease	9.1
Cause Unknown	Cause Unknown	4.2
Polycyclic Aromatic Hydrocarbons (PAHs) (Aquatic Ecosystems)	Toxic Organics	1.9
Alterations in Wetland Habitats	Habitat Alterations	.6
Lead	Metals (other than Mercury)	.4
Mercury	Mercury	.4
Zinc	Metals (other than Mercury)	.2
Copper	Metals (other than Mercury)	.2
Dioxin (Including 2,3,7,8-TCDD)	Dioxins	.2
Silver	Metals (other than Mercury)	.0
Gold	Metals (other than Mercury)	.0

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Site-specific Targeted Monitoring Results

Probable Sources
Connecticut Bays and Estuaries 2006

Description of this table

Probable Source	Probable Source Group	Square Miles Threatened or Impaired
Unspecified Urban Stormwater	Urban-Related Runoff/Stormwater	375.1
Residential Districts	Urban-Related Runoff/Stormwater	373.4
Non-Point Source	Unspecified Nonpoint Source	351.2
Municipal Point Source Discharges	Municipal Discharges/Sewage	269.5
Combined Sewer Overflows	Municipal Discharges/Sewage	266.1
Atmospheric Deposition - Nitrogen	Atmospheric Deposition	260.1
Industrial Point Source Discharge	Industrial	259.7
Waterfowl	Natural/Wildlife	155.4
Marina/Boating Sanitary On-Vessel Discharges	Recreational Boating And Marinas	155.2
On-Site Treatment Systems (Septic Systems And Similar Decencentralized Systems)	Municipal Discharges/Sewage	117.7
Wet Weather Discharges (Point Source And Combination Of Stormwater, Sso Or Cso)	Municipal Discharges/Sewage	102.9
Source Unknown	Unknown	54.0
Contaminated Sediments	Legacy/Historical Pollutants	11.0
Landfills	Land Application/Waste Sites/Tanks	6.9
Sanitary Sewer Overflows (Collection System Failures)	Municipal Discharges/Sewage	3.1
Agriculture	Agriculture	1.5
Sources Outside State Juristiction Or Borders	Other	1.0
Highway/Road/Bridge Runoff (Non-Construction Related)	Urban-Related Runoff/Stormwater	1.0
Dredge Mining	Resource Extraction	.6
Other Spill Related Impacts	Spills/Dumping	.4
Industrial/Commercial Site Stormwater Discharge (Permittted)	Urban-Related Runoff/Stormwater	.2
Airports	Industrial	.2

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Connecticut Causes of Impairment for Reporting Year 2006

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)
Algal Growth		3,688.7
Ammonia	3.9	.6
Cause Unknown	314.5		4.2
Cause Unknown - Impaired Biota			11.6
Chlorine	6.1
Dioxins			.2
Flow Alteration(s)	33.8	214.4
Habitat Alterations	40.6	95.6	.6
Mercury	3.8	810.0	.4
Metals (other than Mercury)	14.8	24.1	.6
Nuisance Exotic Species		389.4
Nutrients	.6	3,968.0	276.2
Oil and Grease	.1		9.1
Organic Enrichment/Oxygen Depletion	.6	450.0	285.9
Pathogens	413.1	1,216.6	150.4
Pesticides		53.9
Polychlorinated Biphenyls (PCBs)	127.8	3,068.6	18.0
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 2006

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)
Agriculture	44.5	1,971.9	1.5
Atmospheric Deposition		625.3	260.1
Construction	37.9
Habitat Alterations (Not Directly Related To Hydromodification)	20.6	95.6
Hydromodification	111.4	899.1
Industrial	109.3	3,018.8	259.7
Land Application/Waste Sites/Tanks	49.6	.6	6.9
Legacy/Historical Pollutants	48.8	3,098.3	11.0
Municipal Discharges/Sewage	206.9	2,136.4	333.5
Natural/Wildlife	8.9	1,009.0	155.4
Other	106.6	3,050.2	1.0
Recreation And Tourism (Non-Boating)	22.2
Recreational Boating And Marinas			155.2
Resource Extraction	24.1	44.5	.6
Spills/Dumping	28.7	100.1	.4
Unknown	392.9	2,891.7	54.0
Unspecified Nonpoint Source	2.1	1,782.4	351.2
Urban-Related Runoff/Stormwater	216.4	2,207.3	375.4

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Connecticut TMDL Alternatives by Cause of Impairment 2006

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.
Polychlorinated Biphenyls (PCBs)	10	49	2,861
Lead	2			0
Chlorine	1	1
Chlorophyll-A	1		339
Cobalt	1	1
Diesel Fuel	1	0
Dissolved Oxygen Saturation	1		339
Excess Algal Growth	1		339
Mercury	1	0
Nutrient/Eutrophication Biological Indicators	1		339
Sulfates	1	0
Uranium	1	1

Total: 22 TMDL Alternatives

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Connecticut Previously 303(d)-Listed Waters Now Attaining All Applicable Water Quality Standards

Description of this table

Year Attaining	Number of Waters Attaining	Number of Causes of Impairment Addressed
NOTE: Click on the underlined "Number of Waters Attaining" value for a detailed list of those previously 303(d)-listed waters now attaining all applicable water quality standards.
2004	6	9
2006	3	5
2011	9	9

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Connecticut Causes of Impairment for 303(d) Listed Waters

Description of this table

Cause of Impairment Group Name	Number of Causes of Impairment Reported
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.
Pathogens	206
Cause Unknown	102
Organic Enrichment/Oxygen Depletion	39
Nutrients	33
Polychlorinated Biphenyls (PCBs)	22
Metals (other than Mercury)	18
Algal Growth	18
Mercury	11
Sediment	5
Turbidity	4
Cause Unknown - Impaired Biota	3
Oil and Grease	3
Ammonia	2
Pesticides	2
Toxic Organics	2
Chlorine	1
Other Cause	1
Salinity/Total Dissolved Solids/Chlorides/Sulfates	1
Taste, Color and Odor	1
Dioxins	1
Total Toxics	1

Total: 476 Causes of Impairment

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Connecticut Cumulative TMDLs by Pollutant

This chart includes TMDLs since October 1, 1995.

Description of this table

Pollutant	Number of TMDLs	Number of Causes of Impairment Addressed
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.
Escherichia Coli (E. Coli)	230	235
Fecal Coliform	47	47
Copper	6	6
Zinc	5	5
Chlorine	4	4
Enterococcus Bacteria	4	4
Algal Growth	3	3
Ammonia	3	3
Lead	3	3
1,2-Propanediol	2	2
Ethylene Glycol	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: 325 TMDLs; 330 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

Fiscal Year	Number of TMDLs	Number of Causes of Impairment Addressed
NOTE: Click on the underlined "Number of TMDLs Completed" value for a detailed list of the TMDLs for the fiscal year.
2000	11	11
2001	9	9
2002	7	7
2004	3	3
2005	30	30
2006	16	16
2007	7	7
2008	26	27
2010	9	9
2011	25	25
2012	182	186

Total: 325 TMDLs; 330 Causes of Impairment Addressed

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TMDL Document Search

Full Text Search of TMDL Documents

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