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National Assessment Data 2002

Assessed Waters of the United States by Water Type Water Quality by Waterbody Type Rivers, Streams, and Creeks Individual Use Support for Assessed Waters Water Quality Attainment for Assessed Waters Top Ten National Causes of Impairments Top Ten National Probable Sources of Impairments Lakes, Ponds, and Reservoirs Individual Use Support for Assessed Waters Water Quality Attainment for Assessed Waters Top Ten National Causes of Impairments Top Ten National Probable Sources of Impairments Bays and Estuaries Individual Use Support for Assessed Waters Water Quality Attainment for Assessed Waters Top Ten National Causes of Impairments Top Ten National Probable Sources of Impairments Coastal Shorelines Individual Use Support for Assessed Waters Water Quality Attainment for Assessed Waters Top Ten National Causes of Impairments Top Ten National Probable Sources of Impairments Oceans, and Near Coastal Waters Individual Use Support for Assessed Waters Water Quality Attainment for Assessed Waters Top Ten National Causes of Impairments Top Ten National Probable Sources of Impairments Wetlands Individual Use Support for Assessed Waters Water Quality Attainment for Assessed Waters Top Ten National Causes of Impairments Top Ten National Probable Sources of Impairments Great Lakes Shoreline Individual Use Support for Assessed Waters Water Quality Attainment for Assessed Waters Top Ten National Causes of Impairments Top Ten National Probable Sources of Impairments Great Lakes Open Water Individual Use Support for Assessed Waters Water Quality Attainment for Assessed Waters Top Ten National Causes of Impairments Top Ten National Probable Sources of Impairments Causes of Impairment Probable Sources Contributing to Impairment State URL for Water Quality Hardcopy 305(b) Summary Report Glossary

National Assessment Database About this Database Assessing Water Quality (Questions and Answers) National Water Quality Inventory Report to Congress, 2002 Reporting Cycle The 2002 National Assessment Database (Fact Sheet) Previous National Water Quality Reports EnviroMapper for Water

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Assessed Waters of the United States

Description of this table

	Size Of Water
	Rivers, Streams, Creeks (Miles)	Lakes, Ponds, Reservoir (Acres)	Bays, Estuaries (Square Miles)	Coastal Shorelines (Miles)	Oceans, Near Coastal Waters (Square Miles)	Wetlands (Acres)	Great Lakes Shoreline (Miles)	Great Lakes Open Water (Square Miles)
Total Assessed Waters	695,540.37	14,831,882.35	30,445.72	2,570.68	4,952.42	1,255,423.63	519.22	50,866.46
Estimated Total Water Size in US	3,692,830.00	40,603,893.00	87,369.00	58,618.00	54,120.00	105,500,000.00	5,521.00	60,546.00
Percent of Waters Assessed	18.83	36.53	34.85	4.39	9.15	1.19	9.40	84.01

National Assessed Waters
Individual Use Support for Rivers and Streams

Description of this table

EPA Designated Use		Total Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Fish, Shellfish, and Wildlife Protection and Propagation	596,433.07	55.37	3.73	40.90
	Recreation	321,749.90	64.12	3.03	32.85
	Public Water Supply	150,491.90	80.69	1.54	17.78
	Aquatic Life Harvesting	186,720.91	56.98	16.03	27.00
	Agricultural	189,331.50	92.02	.77	7.20
	Industrial	35,917.02	73.60	.15	26.25
	Aesthetic Value	25,184.71	76.43	.91	22.66
	Other	18,998.94	27.71	1.35	70.93
	Exceptional Recreational or Ecological Significance	15,908.86	11.05	4.72	84.23

695,540.37 miles of rivers and streams were assessed, or 18.83% of 3,692,830.00 total miles.

National Assessed Waters
Water Quality Attainment for Rivers and Streams

Description of this table

Attainment Status	Miles	Percent of Assessed
Good	358,034.88	51.48
Threatened	27,749.97	3.99
Impaired	309,755.53	44.53
Total Miles Assessed	695,540.37	100.00

Top Ten National Causes of Impairments
for Rivers and Streams

Description of this table

	Cause Name	Total Miles Impaired
1	SEDIMENT/SILTATION	100,445.87
2	PATHOGENS	82,132.98
3	HABITAT ALTERATIONS	80,974.29
4	METALS	52,809.48
5	NUTRIENTS	52,227.56
6	THERMAL MODIFICATIONS	51,738.32
7	ORGANIC ENRICHMENT/LOW DISSOLVED OXYGEN	51,549.52
8	FLOW ALTERATIONS	48,925.16
9	CAUSE UNKNOWN	25,180.67
10	pH/ACIDITY/CAUSTIC CONDITIONS	18,295.47

Top Ten National Sources of Impairments
for Rivers and Streams

Description of this table

	EPA Source Name	Total Miles Impaired by Source
1	AGRICULTURE	113,662.70
2	UNKNOWN	91,823.72
3	HYDROMODIFICATION	79,399.66
4	HABITAT ALTERATIONS (NOT DIRECTLY RELATED TO HYDROMODIFICATION)	51,297.85
5	NATURAL	41,764.05
6	URBAN-RELATED RUNOFF/STORMWATER	38,114.89
7	MUNICIPAL PERMITTED DISCHARGES (DIRECT AND INDIRECT)	32,438.24
8	RESOURCE EXTRACTION	28,722.37
9	SILVICULTURE (FORESTRY)	18,463.23
10	INDUSTRIAL	17,405.02

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National Assessed Waters
Individual Use Support for Lakes, Ponds and Reservoirs

Description of this table

EPA Designated Use		Total Acres Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Fish, Shellfish, and Wildlife Protection and Propagation	9,738,350.58	45.92	7.23	46.85
	Recreation	9,564,367.35	60.26	3.44	36.30
	Public Water Supply	5,669,056.67	74.55	3.51	21.94
	Aquatic Life Harvesting	4,562,746.31	40.78	11.45	47.77
	Agricultural	2,931,969.88	70.84	12.83	16.33
	Industrial	1,678,879.85	69.50	.28	30.22
	Aesthetic Value	1,031,627.90	51.09	2.21	46.70
	Other	971,409.76	32.38	.99	66.63
	Exceptional Recreational or Ecological Significance	767,060.25	9.12	3.16	87.73

14,831,882.35 acres of lakes, ponds and reservoirs were assessed, or 36.53% of 40,603,893.00 total acres.

National Assessed Waters
Water Quality Attainment for Lakes, Ponds and Reservoirs

Description of this table

Attainment Status	Acres	Percent of Assessed
Good	7,073,207.01	47.69
Threatened	810,774.82	5.47
Impaired	6,947,900.51	46.84
Total Acres Assessed	14,831,882.35	100.00

Top Ten National Causes of Impairments
for Lakes, Ponds and Reservoirs

Description of this table

	Cause Name	Total Acres Impaired
1	NUTRIENTS	2,864,710.69
2	METALS	2,827,608.22
3	ORGANIC ENRICHMENT/LOW DISSOLVED OXYGEN	1,339,070.42
4	SEDIMENT/SILTATION	1,317,938.02
5	NUISANCE EXOTIC SPECIES	1,264,022.52
6	TOXIC ORGANICS	801,595.96
7	HARMFUL ALGAL BLOOMS (HABs)	724,042.98
8	SALINITY/TDS/CHLORIDES	650,960.72
9	FLOW ALTERATIONS	592,360.99
10	TURBIDITY	487,784.09

Top Ten National Sources of Impairments
for Lakes, Ponds and Reservoirs

Description of this table

	EPA Source Name	Total Acres Impaired by Source
1	UNKNOWN	2,743,374.10
2	AGRICULTURE	2,093,641.13
3	ATMOSPHERIC DEPOSITION	1,829,672.24
4	LAND APPLICATION/WASTE SITES	1,540,223.99
5	HYDROMODIFICATION	1,525,224.08
6	OTHER	1,295,104.21
7	NATURAL	1,251,035.22
8	SPILLS AND UNPERMITTED DISCHARGES	1,164,089.76
9	URBAN-RELATED RUNOFF/STORMWATER	948,420.23
10	MUNICIPAL PERMITTED DISCHARGES (DIRECT AND INDIRECT)	823,510.09

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National Assessed Waters
Individual Use Support for Bays and Estuaries

Description of this table

EPA Designated Use		Total Square Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Fish, Shellfish, and Wildlife Protection and Propagation	29,064.49	68.59	2.55	28.86
	Recreation	9,289.96	84.48	.53	14.99
	Public Water Supply	213.93	22.31	.00	77.69
	Aquatic Life Harvesting	10,024.82	67.60	3.47	28.93
	Industrial	570.32	74.06	.02	25.92
	Exceptional Recreational or Ecological Significance	561.56	.79	.00	99.21
	Aesthetic Value	342.38	37.23	.00	62.77
	Other	299.19	28.00	.00	72.00
	Agricultural	92.06	42.39	.00	57.61

30,445.72 square miles of bays and estuaries were assessed, or 34.85% of 87,369.00 total square miles.

National Assessed Waters
Water Quality Attainment for Bays and Estuaries

Description of this table

Attainment Status	Square Miles	Percent of Assessed
Good	19,915.70	65.41
Threatened	694.27	2.28
Impaired	9,835.75	32.31
Total Square Miles Assessed	30,445.72	100.00

Top Ten National Causes of Impairments
for Bays and Estuaries

Description of this table

	Cause Name	Total Square Miles Impaired
1	METALS	4,939.58
2	NUTRIENTS	2,229.23
3	ORGANIC ENRICHMENT/LOW DISSOLVED OXYGEN	2,214.03
4	PATHOGENS	2,141.23
5	CAUSE UNKNOWN	2,048.17
6	BIOLOGIC INTEGRITY (BIOASSESSMENTS)	1,965.36
7	TURBIDITY	1,622.12
8	PESTICIDES	1,255.70
9	HARMFUL ALGAL BLOOMS (HABs)	1,220.74
10	TOXIC ORGANICS	1,130.19

Top Ten National Sources of Impairments
for Bays and Estuaries

Description of this table

	EPA Source Name	Total Square Miles Impaired by Source
1	UNKNOWN	5,235.23
2	INDUSTRIAL	4,905.69
3	MUNICIPAL PERMITTED DISCHARGES (DIRECT AND INDIRECT)	3,444.97
4	RESOURCE EXTRACTION	2,826.53
5	URBAN-RELATED RUNOFF/STORMWATER	2,742.70
6	ATMOSPHERIC DEPOSITION	2,580.14
7	OTHER	2,139.01
8	HYDROMODIFICATION	1,325.76
9	LAND APPLICATION/WASTE SITES	1,278.66
10	NATURAL	1,155.67

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National Assessed Waters
Individual Use Support for Coastal Shorelines

Description of this table

EPA Designated Use		Total Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Fish, Shellfish, and Wildlife Protection and Propagation	2,488.06	82.63	.33	17.04
	Recreation	1,788.30	85.19	.00	14.81
	Public Water Supply	544.06	86.39	.00	13.61
	Aquatic Life Harvesting	1,316.79	83.18	.00	16.82
	Other	1,037.68	91.32	.00	8.68
	Exceptional Recreational or Ecological Significance	501.03	85.74	.00	14.26
	Agricultural	494.97	89.91	.00	10.09
	Aesthetic Value	445.01	100.00	.00	.00
	Industrial	302.74	79.46	.00	20.54

2,570.68 miles of coastal shorelines were assessed, or 4.39% of 58,618.00 total miles.

National Assessed Waters
Water Quality Attainment for Coastal Shorelines

Description of this table

Attainment Status	Miles	Percent of Assessed
Good	2,131.08	82.90
Threatened	8.20	.32
Impaired	431.40	16.78
Total Miles Assessed	2,570.68	100.00

Top Ten National Causes of Impairments
for Coastal Shorelines

Description of this table

	Cause Name	Total Miles Impaired
1	PATHOGENS	274.50
2	METALS	157.82
3	PESTICIDES	137.51
4	DIOXINS	108.10
5	NUTRIENTS	99.90
6	TOXIC ORGANICS	87.43
7	TURBIDITY	86.40
8	SUSPENDED SOLIDS	78.30
9	SEDIMENT/SILTATION	71.50
10	ORGANIC ENRICHMENT/LOW DISSOLVED OXYGEN	43.30

Top Ten National Sources of Impairments
for Coastal Shorelines

Description of this table

	EPA Source Name	Total Miles Impaired by Source
1	URBAN-RELATED RUNOFF/STORMWATER	230.69
2	UNKNOWN	139.06
3	INDUSTRIAL	131.56
4	NATURAL	119.34
5	AGRICULTURE	116.54
6	SPILLS AND UNPERMITTED DISCHARGES	63.31
7	MUNICIPAL PERMITTED DISCHARGES (DIRECT AND INDIRECT)	50.60
8	SEWAGE	50.26
9	OTHER	34.49
10	LAND APPLICATION/WASTE SITES	29.80

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National Assessed Waters
Individual Use Support for Oceans, and Near Coastal

Description of this table

EPA Designated Use		Total Square Miles Assessed	Percent Good	Percent Threatened	Percent Impaired	% Good
						% Threatened
						% Impaired
	Fish, Shellfish, and Wildlife Protection and Propagation	4,863.38	12.37	.01	87.62