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Data are also available for these years:  2002  2004  2006

303(d) Listed Waters for 2008

Waterbody Changes from Prior Cycle

Comparison Summary by Reporting Year

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Colorado 2008 Water Quality Assessment Report

Assessed Waters of Colorado by Watershed

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Display impaired waters and TMDL information only

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Colorado Assessment Summary for Reporting Year 2008

Description of this table
  Size of Water
Rivers and
Streams (Miles)		 Lakes, Reservoirs,
and Ponds (Acres)
   Good Waters 62,370.4 52,635.9
      Previously impaired waters
      now attaining all uses
   Threatened Waters
      TMDL completed        
      TMDL alternative        
      Non-pollutant impairment        
      TMDL needed        
   Impaired Waters 10,376.4 41,504.1
      TMDL completed     276.3    
      TMDL alternative        
      Non-pollutant impairment        
      TMDL needed     10,098.3     41,504.1
         New TMDLs completed     232.9     .0
         Remaining TMDLs needed           9,865.5           41,504.1
Total Assessed Waters 72,746.9 94,139.9
Total Waters 107,403.0 164,029.0
Percent of Waters Assessed 67.7 57.4

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


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

Description of this table
Assessed Status Miles
Assessed 72,746.9
Unassessed 34,656.1
Total Miles 107,403.0







arrow pointing right 		Description of this table
Attainment Status Miles
Good 62,370.4
Threatened .0
Impaired 10,376.4
Total Miles Assessed 72,746.9







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TMDL Development Status Miles
All TMDLs completed 509.2
TMDL alternative .0
Non-pollutant impairment .0
TMDL needed 9,865.5
Total Threatened and Impaired 10,376.4

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Colorado 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
Agriculture 69,033.2 95.8 .0 4.2 color.gifcolor.gif
Aquatic Life Cold Water-Class 1 25,934.7 92.2 .0 7.8 color.gifcolor.gif
Aquatic Life Cold Water-Class 2 5,777.2 83.4 .0 16.6 color.gifcolor.gif
Aquatic Life Warm Water-Class 1 1,438.1 38.3 .0 61.7 color.gifcolor.gif
Aquatic Life Warm Water-Class 2 24,632.8 80.4 .0 19.6 color.gifcolor.gif
Domestic Water Source 41,089.1 96.4 .0 3.6 color.gifcolor.gif
Recreation Primary Contact 44,531.5 95.1 .0 4.9 color.gifcolor.gif
Recreation Secondary Contact 15,666.8 98.9 .0 1.1 color.gifcolor.gif

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Colorado 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
Selenium Metals (other than Mercury) color.gif 6,866.5
Escherichia Coli (E. Coli) Pathogens color.gif 2,350.0
Iron Metals (other than Mercury) color.gif 950.8
Zinc Metals (other than Mercury) color.gif 809.9
Copper Metals (other than Mercury) color.gif 602.2
Cadmium Metals (other than Mercury) color.gif 492.5
pH pH/Acidity/Caustic Conditions color.gif 196.2
Lead Metals (other than Mercury) color.gif 174.8
Sedimentation/Siltation Sediment color.gif 117.9
Aluminum Metals (other than Mercury) color.gif 91.0
Uranium Radiation color.gif 80.5
Cause Unknown Cause Unknown color.gif 70.5
Ammonia, Un-ionized Ammonia color.gif 67.4
Sulfates Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 22.4
Manganese Metals (other than Mercury) color.gif 20.4
BOD, Sediment Load (Sediment Oxygen Demand) Organic Enrichment/Oxygen Depletion color.gif 12.5
Dissolved Oxygen Saturation Organic Enrichment/Oxygen Depletion color.gif 12.4
Nitrate/Nitrite (Nitrite + Nitrate as N) Nutrients color.gif 11.2

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Colorado 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 color.gif 5,886.2
Agriculture Agriculture color.gif 2,625.7
Natural Sources Natural/Wildlife color.gif 827.7
Impacts From Abandoned Mine Lands (Inactive) Resource Extraction color.gif 627.1
Upstream Source Other color.gif 67.8
Contaminated Groundwater Groundwater Loadings/Withdrawals color.gif 26.7
Highway/Road/Bridge Runoff (Non-Construction Related) Urban-Related Runoff/Stormwater color.gif 16.8
Mine Tailings Resource Extraction color.gif 11.2

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

Description of this table
Assessed Status Acres
Assessed 94,139.9
Unassessed 69,889.1
Total Acres 164,029.0







arrow pointing right 		Description of this table
Attainment Status Acres
Good 52,635.9
Threatened .0
Impaired 41,504.1
Total Acres Assessed 94,139.9







arrow pointing right 		Description of this table
TMDL Development Status Acres
All TMDLs completed .0
TMDL alternative .0
Non-pollutant impairment .0
TMDL needed 41,504.1
Total Threatened and Impaired 41,504.1

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Colorado 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
Agriculture 88,908.6 100.0 .0 .0 color.gif
Aquatic Life Cold Water-Class 1 47,108.5 64.8 .0 35.2 color.gifcolor.gif
Aquatic Life Cold Water-Class 2 142.0 .0 .0 100.0 color.gif
Aquatic Life Warm Water-Class 1 31,207.9 34.7 .0 65.3 color.gifcolor.gif
Aquatic Life Warm Water-Class 2 4,685.1 6.3 .0 93.7 color.gifcolor.gif
Domestic Water Source 64,121.4 100.0 .0 .0 color.gif
Recreation Primary Contact 76,713.4 100.0 .0 .0 color.gif
Recreation Secondary Contact 2,449.5 100.0 .0 .0 color.gif

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Colorado 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
Selenium Metals (other than Mercury) color.gif 17,696.0
Mercury in Fish Tissue Mercury color.gif 15,081.8
Dissolved Oxygen Saturation Organic Enrichment/Oxygen Depletion color.gif 5,016.1
pH pH/Acidity/Caustic Conditions color.gif 3,834.9
Dissolved Oxygen Organic Enrichment/Oxygen Depletion color.gif 1,807.1
Chlorophyll-A Algal Growth color.gif 916.2
Iron Metals (other than Mercury) color.gif 672.5
Ammonia, Un-ionized Ammonia color.gif 530.5
Copper Metals (other than Mercury) color.gif 142.0
Tetrachloroethylene Toxic Organics color.gif 78.4

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Colorado 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
Source Unknown Unknown color.gif 36,542.6
Impacts From Abandoned Mine Lands (Inactive) Resource Extraction color.gif 142.0
Natural Sources Natural/Wildlife color.gif 142.0
Contaminated Groundwater Groundwater Loadings/Withdrawals color.gif 78.4

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Colorado 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)
Algal Growth 916.2
Ammonia 67.4 530.5
Cause Unknown 70.5
Mercury 15,081.8
Metals (other than Mercury) 8,558.9 18,368.5
Nutrients 11.2
Organic Enrichment/Oxygen Depletion 24.9 6,823.2
Pathogens 2,350.0
pH/Acidity/Caustic Conditions 196.2 3,834.9
Radiation 80.5
Salinity/Total Dissolved Solids/Chlorides/Sulfates 22.4
Sediment 117.9
Toxic Organics 78.4

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Colorado 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)
Agriculture 2,625.7
Groundwater Loadings/Withdrawals 26.7 78.4
Natural/Wildlife 827.7 142.0
Other 67.8
Resource Extraction 638.3 142.0
Unknown 5,886.2 36,542.6
Urban-Related Runoff/Stormwater 16.8

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Colorado TMDL Alternatives by Cause of Impairment 2008


No TMDL Alternatives reported.

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Colorado 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
2008 color.gif 7 8

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Colorado 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
Metals (other than Mercury) color.gif 219
Pathogens color.gif 22
pH/Acidity/Caustic Conditions color.gif 16
Organic Enrichment/Oxygen Depletion color.gif 15
Mercury color.gif 13
Sediment color.gif 5
Cause Unknown color.gif 4
Salinity/Total Dissolved Solids/Chlorides/Sulfates color.gif 2
Ammonia color.gif 2
Radiation color.gif 2
Nutrients color.gif 1
Algal Growth color.gif 1
Toxic Organics color.gif 1

Total: 303 Causes of Impairment

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Colorado 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
Ammonia color.gif 128 129
Fecal Coliform color.gif 126 126
Total Residual Chlorine color.gif 99 101
Zinc color.gif 69 72
Copper color.gif 68 68
Chlorine color.gif 45 45
Cadmium color.gif 42 44
Ammonia, Un-ionized color.gif 41 41
Lead color.gif 39 39
Iron color.gif 38 38
Mercury color.gif 27 27
Silver color.gif 26 26
Escherichia Coli (E. Coli) color.gif 22 22
Manganese color.gif 21 21
Fecal color.gif 20 20
Cyanide color.gif 17 17
Selenium color.gif 17 17
Chlorine, Residual (Chlorine Demand) color.gif 14 14
Aluminum color.gif 8 9
Boron color.gif 8 8
Chromium VI color.gif 8 8
Arsenic color.gif 7 7
Phosphorus color.gif 6 8
Sediment color.gif 5 5
Chloride color.gif 4 4
Chromium color.gif 4 4
Chromium III color.gif 4 4
pH color.gif 4 4
Dissolved Oxygen color.gif 3 3
Nickel color.gif 3 3
Sulfide color.gif 3 3
Total Inorganic Nitrogen color.gif 3 3
Uranium color.gif 3 3
Benzene color.gif 2 2
MTBE color.gif 2 2
Nitrate color.gif 2 2
Radium color.gif 2 2
1,2-Dichloroethane color.gif 1 1
Antimony color.gif 1 1
Benzo[a]pyrene color.gif 1 1
Beryllium color.gif 1 1
Chromium IV color.gif 1 1
Contaminated Sediments (Copper) color.gif 1 1
Contaminated Sediments (Nickel) color.gif 1 1
Fluoride color.gif 1 1
Mercury in Fish Tissue color.gif 1 1
Nitrogen color.gif 1 1
Other Toxic Organics color.gif 1 1
Sulfate color.gif 1 1
Tetrachloroethene color.gif 1 1
Thallium color.gif 1 1
Trichloroethene color.gif 1 1

Total: 955 TMDLs; 966 Causes of Impairment Addressed


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Colorado 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
1997 color.gif 94 96
1998 color.gif 23 23
1999 color.gif 42 42
2000 color.gif 36 36
2001 color.gif 40 40
2002 color.gif 137 139
2003 color.gif 50 50
2004 color.gif 153 154
2005 color.gif 166 166
2006 color.gif 75 75
2007 color.gif 70 71
2008 color.gif 42 45
2009 color.gif 27 29

Total: 955 TMDLs; 966 Causes of Impairment Addressed

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