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On This Page 303(d) Listed Waters for 2006

Data are also available for these cycles:
2002 2004

Waterbody Changes from Prior Cycle

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Delaware Water Quality Assessment Report

Assessed Waters of Delaware by Watershed

Select a watershed from the list:
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Search for a waterbody within Delaware
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Display impaired waters and TMDL information only


NOTE: The data provided in this report differs slightly from the information provided in the original Delaware 2006 305(b) report. This is a result of differences between the Delaware State assessment database and the summary data provided in Delaware's 2006 Integrated Report, which is available at http://www.dnrec.state.de.us/water2000/Sections/Watershed/TMDL/2006%20305(b)Final.pdf



Site-specific Targeted Monitoring Summary Results

Delaware (2006)

Description of this table
 
    8.8 90.0 25.0
      
   
                          
                          
                          
                          
    2,497.3 2,863.9 29.5
           476.3     1,427.5     3.0     
                          
                          
           2,020.9     1,436.4     26.5     
              .0     .0     .0     .0
                    2,020.9           1,436.4           26.5          
2,506.1 2,953.9 29.5 25.0
2,509.0 2,954.0 448.5 25.0
99.9 100.0 6.6 100.0

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


Site-specific Targeted Monitoring Results

Delaware Rivers and Streams 2006

Description of this table

All
Rivers and Streams

2,509.0 Miles of Rivers and Streams

Assessed 2,506.1
Unassessed 2.9
Total Miles 2,509.0







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Description of this table

Assessed
Rivers and Streams

2,506.1 Miles of
Assessed Rivers and Streams

Good 8.8
Threatened .0
Impaired 2,497.3
Total Miles Assessed 2,506.1







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Description of this table

Threatened and Impaired
Rivers and Streams

2,497.3 Miles of
Threatened and Impaired
Rivers and Streams

476.3
.0
.0
2,020.9
Total Threatened and Impaired 2,497.3

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Delaware Rivers and Streams 2006

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

Description of this table
% Good
% Threatened
% Impaired
Agricultural Water Supply 1,928.1 100.0 .0 .0 color.gif
Cold Water Fish 66.6 80.8 .0 19.2 color.gifcolor.gif
Fish, Aquatic Life, And Wildlife 2,478.2 2.9 .0 97.1 color.gifcolor.gif
Harvestable Shellfish Waters 5.2 .0 .0 100.0 color.gif
Industrial Water Supply 2,448.7 100.0 .0 .0 color.gif
Primary Contact Recreation 2,479.4 11.6 .0 88.4 color.gifcolor.gif
Public Water Supply 204.5 97.1 .0 2.9 color.gifcolor.gif
Secondary Contact Recreation 2,475.0 100.0 .0 .0 color.gif
Waters Of Exceptional Recreational Or Ecological Significance 867.3 21.9 .0 78.1 color.gifcolor.gif

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Site-specific Targeted Monitoring Results

Causes of Impairment
Delaware Rivers and Streams 2006

Description of this table
Phosphorus, Total Nutrients color.gif 2,191.3
Nitrogen, Total Nutrients color.gif 2,079.6
Enterococcus Bacteria Pathogens color.gif 1,898.3
Habitat Assessment (Streams) Cause Unknown - Impaired Biota color.gif 268.9
Nitrate/Nitrite (Nitrite + Nitrate as N) Nutrients color.gif 185.8
Polychlorinated Biphenyls (PCBs) Polychlorinated Biphenyls (PCBs) color.gif 114.6
Total Kjehldahl Nitrogen (TKN) Nutrients color.gif 91.5
Organic Enrichment (Sewage) Biological Indicators Organic Enrichment/Oxygen Depletion color.gif 75.6
Dioxin (Including 2,3,7,8-TCDD) Dioxins color.gif 72.6
Dieldrin Pesticides color.gif 37.8
Chlordane Pesticides color.gif 31.8
Mercury Mercury color.gif 24.1
Ammonia, Un-ionized Ammonia color.gif 21.3
DDT in Fish Tissue Pesticides color.gif 17.0
DDT Pesticides color.gif 12.8
Zinc Metals (other than Mercury) color.gif 12.8
Temperature, Water Temperature color.gif 9.4
Solids (Suspended/Bedload) Sediment color.gif 9.4
Cause Unknown Cause Unknown color.gif 6.9

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Site-specific Targeted Monitoring Results

Probable Sources
Delaware Rivers and Streams 2006

Description of this table
Agriculture Agriculture color.gif 847.9
Natural Sources Natural/Wildlife color.gif 423.5
Source Unknown Unknown color.gif 247.5
On-Site Treatment Systems (Septic Systems And Similar Decencentralized Systems) Municipal Discharges/Sewage color.gif 172.1
Municipal Point Source Discharges Municipal Discharges/Sewage color.gif 118.4
Industrial Point Source Discharge Industrial color.gif 105.0
Rcra Hazardous Waste Sites Industrial color.gif 10.0
Combined Sewer Overflows Municipal Discharges/Sewage color.gif 9.3
Site Clearance (Land Development Or Redevelopment) Construction color.gif 8.2
Construction Stormwater Discharge (Permitted) Construction color.gif 8.2
Landfills Land Application/Waste Sites/Tanks color.gif 5.2

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Site-specific Targeted Monitoring Results

Delaware Lakes, Reservoirs, and Ponds 2006

Description of this table

All
Lakes, Reservoirs, and Ponds

2,954.0 Acres of Lakes, Reservoirs, and Ponds

Assessed 2,953.9
Unassessed .1
Total Acres 2,954.0







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Description of this table

Assessed
Lakes, Reservoirs, and Ponds

2,953.9 Acres of
Assessed Lakes, Reservoirs, and Ponds

Good 90.0
Threatened .0
Impaired 2,863.9
Total Acres Assessed 2,953.9







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Description of this table

Threatened and Impaired
Lakes, Reservoirs, and Ponds

2,863.9 Acres of
Threatened and Impaired
Lakes, Reservoirs, and Ponds

1,427.5
.0
.0
1,436.4
Total Threatened and Impaired 2,863.9

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Delaware 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
% Good
% Threatened
% Impaired
Agricultural Water Supply 2,764.6 100.0 .0 .0 color.gif
Fish, Aquatic Life, And Wildlife 2,953.9 11.3 .0 88.7 color.gifcolor.gif
Industrial Water Supply 2,953.9 100.0 .0 .0 color.gif
Primary Contact Recreation 2,953.9 55.6 .0 44.4 color.gifcolor.gif
Public Water Supply 295.6 100.0 .0 .0 color.gif
Secondary Contact Recreation 2,942.0 82.4 .0 17.6 color.gifcolor.gif
Waters Of Exceptional Recreational Or Ecological Significance 757.8 33.9 .0 66.1 color.gifcolor.gif

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Site-specific Targeted Monitoring Results

Causes of Impairment
Delaware Lakes, Reservoirs, and Ponds 2006

Description of this table
Phosphorus, Total Nutrients color.gif 2,512.5
Nitrogen, Total Nutrients color.gif 2,203.9
Enterococcus Bacteria Pathogens color.gif 983.6
Nitrate/Nitrite (Nitrite + Nitrate as N) Nutrients color.gif 390.4
Polychlorinated Biphenyls (PCBs) Polychlorinated Biphenyls (PCBs) color.gif 210.5
Mercury Mercury color.gif 183.4
Dioxin (Including 2,3,7,8-TCDD) Dioxins color.gif 157.8
Total Kjehldahl Nitrogen (TKN) Nutrients color.gif 150.0
DDT in Fish Tissue Pesticides color.gif 27.1

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Site-specific Targeted Monitoring Results

Probable Sources
Delaware Lakes, Reservoirs, and Ponds 2006

Description of this table
Agriculture Agriculture color.gif 403.6
Source Unknown Unknown color.gif 253.4
Natural Sources Natural/Wildlife color.gif 237.4

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Site-specific Targeted Monitoring Results

Delaware Bays and Estuaries 2006

Description of this table

All
Bays and Estuaries

448.5 Square Miles of Bays and Estuaries

Assessed 29.5
Unassessed 419.0
Total Square Miles 448.5







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Description of this table

Assessed
Bays and Estuaries

29.5 Square Miles of
Assessed Bays and Estuaries

Good .0
Threatened .0
Impaired 29.5
Total Square Miles Assessed 29.5







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Description of this table

Threatened and Impaired
Bays and Estuaries

29.5 Square Miles of
Threatened and Impaired
Bays and Estuaries

3.0
.0
.0
26.5
Total Threatened and Impaired 29.5

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Delaware Bays and Estuaries 2006

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

Description of this table
% Good
% Threatened
% Impaired
Fish, Aquatic Life, And Wildlife 29.0 .0 .0 100.0 color.gif
Harvestable Shellfish Waters 14.5 4.1 .0 95.9 color.gifcolor.gif
Industrial Water Supply 29.0 100.0 .0 .0 color.gif
Primary Contact Recreation 29.5 50.8 .0 49.2 color.gifcolor.gif
Secondary Contact Recreation 29.0 100.0 .0 .0 color.gif
Waters Of Exceptional Recreational Or Ecological Significance 29.5 10.2 .0 89.8 color.gifcolor.gif

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Site-specific Targeted Monitoring Results

Causes of Impairment
Delaware Bays and Estuaries 2006

Description of this table
Organic Enrichment (Sewage) Biological Indicators Organic Enrichment/Oxygen Depletion color.gif 28.0
Nitrate/Nitrite (Nitrite + Nitrate as N) Nutrients color.gif 28.0
Total Kjehldahl Nitrogen (TKN) Nutrients color.gif 28.0
Enterococcus Bacteria Pathogens color.gif 26.5
Phosphorus, Total Nutrients color.gif 26.0
Solids (Suspended/Bedload) Sediment color.gif 12.0
Nitrogen, Total Nutrients color.gif 1.0
Temperature, Water Temperature color.gif 1.0

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Site-specific Targeted Monitoring Results

Probable Sources
Delaware Bays and Estuaries 2006

Description of this table
Municipal Point Source Discharges Municipal Discharges/Sewage color.gif 25.0
On-Site Treatment Systems (Septic Systems And Similar Decencentralized Systems) Municipal Discharges/Sewage color.gif 13.0
Agriculture Agriculture color.gif 12.0
Natural Sources Natural/Wildlife color.gif 3.0
Source Unknown Unknown color.gif 3.0

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Site-specific Targeted Monitoring Results

Delaware Coastal Shoreline 2006

Description of this table

All
Coastal Shoreline

25.0 Miles of Coastal Shoreline

Assessed 25.0
Unassessed .0
Total Miles 25.0







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Description of this table

Assessed
Coastal Shoreline

25.0 Miles of
Assessed Coastal Shoreline

Good 25.0
Threatened .0
Impaired .0
Total Miles Assessed 25.0







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Description of this table

Threatened and Impaired
Coastal Shoreline

.0 Miles of
Threatened and Impaired
Coastal Shoreline

.0
.0
.0
.0
Total Threatened and Impaired .0

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Site-specific Targeted Monitoring Results

Individual Designated Use Support
Delaware Coastal Shoreline 2006

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

Description of this table
% Good
% Threatened
% Impaired
Fish, Aquatic Life, And Wildlife 25.0 100.0 .0 .0 color.gif
Industrial Water Supply 25.0 100.0 .0 .0 color.gif
Primary Contact Recreation 25.0 100.0 .0 .0 color.gif
Secondary Contact Recreation 25.0 100.0 .0 .0 color.gif

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Site-specific Targeted Monitoring Results

Causes of Impairment
Delaware Coastal Shoreline 2006

No causes of impairment reported.

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Site-specific Targeted Monitoring Results

Probable Sources
Delaware Coastal Shoreline 2006

No probable sources of impairments reported.

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Delaware Causes of Impairment for Reporting Year 2006


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. See also Pollution categories summary document (PDF) (20 pp, 557K, About PDF) for brief, non-technical descriptions of general cause categories.
Size of Assessed Waters with Listed Causes of Impairment
Ammonia 21.3
Cause Unknown 6.9
Cause Unknown - Impaired Biota 268.9
Dioxins 72.6 157.8
Mercury 24.1 183.4
Metals (other than Mercury) 12.8
Nutrients 2,211.4 2,594.3 29.0
Organic Enrichment/Oxygen Depletion 75.6 28.0
Pathogens 1,898.3 983.6 26.5
Pesticides 58.8 27.1
Polychlorinated Biphenyls (PCBs) 114.6 210.5
Sediment 9.4 12.0
Temperature 9.4 1.0

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Delaware Probable Sources Contributing to Impairments
for Reporting Year 2006

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.
Size of Assessed Waters with Probable Sources of Impairments
Agriculture 847.9 403.6 12.0
Construction 8.2
Industrial 105.0
Land Application/Waste Sites/Tanks 5.2
Municipal Discharges/Sewage 290.6 25.0
Natural/Wildlife 423.5 237.4 3.0
Unknown 247.5 253.4 3.0

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Delaware TMDL Alternatives by Cause of Impairment 2006


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.
Nitrate/Nitrite (Nitrite + Nitrate as N) color.gif 1 11
Organic Enrichment (Sewage) Biological Indicators color.gif 1 11
Phosphorus, Total color.gif 1 11
Total Kjehldahl Nitrogen (TKN) color.gif 1 11

Total: 4 TMDL Alternatives

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


No previously 303(d)-listed waters reported as now attaining all applicable water quality standards.

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Delaware 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.
Nutrients color.gif 84
Pathogens color.gif 65
Cause Unknown - Impaired Biota color.gif 19
Polychlorinated Biphenyls (PCBs) color.gif 14
Pesticides color.gif 11
Dioxins color.gif 7
Mercury color.gif 3
Cause Unknown color.gif 1
Organic Enrichment/Oxygen Depletion color.gif 1
Turbidity color.gif 1

Total: 206 Causes of Impairment

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Delaware 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.
Number of Causes of
Impairment Addressed
Phosphorus color.gif 165 173
Bacteria color.gif 149 149
Nitrogen color.gif 114 114
Dissolved Oxygen color.gif 87 87
Ammonia color.gif 17 17
Biochemical Oxygen Demand (BOD) color.gif 16 16
Carbonaceous Bod (CBOD) color.gif 6 6
Nitrogen, Total color.gif 3 3
Nutrients color.gif 3 3
Phosphorus, Total color.gif 3 3
Polychlorinated Biphenyls (PCBs) color.gif 3 3
Zinc color.gif 3 3
Habitat color.gif 2 2
Temperature color.gif 2 2
Total Suspended Solids (TSS) color.gif 2 2
Escherichia Coli (E. Coli) color.gif 1 1
Fecal Coliform color.gif 1 1
NH3-N color.gif 1 1
Phosphates color.gif 1 1

Total: 579 TMDLs; 587 Causes of Impairment Addressed


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Delaware 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.
1998