Water Quality
Water Quality > Hudson River Estuary Data > New York City, Hudson County & Bergen County Sites > Harlem River – Willis Ave. Bridge

Harlem River – Willis Ave. Bridge

Harlem River-Willis Ave. Bridge
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Physical/Chemical Data

Physical, chemical and biological properties of the surface water that are measured continuously while the patrol boat is underway.

Entero Count (fecal indicator) and Rainfall

108 Samples taken

Sample Date [i] Enterococcus Count
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Entero Count

Enterococcus (“Entero”) is a fecal indicating bacterium that lives in the intestines of humans and other warm-blooded animals. It is the EPA preferred indicator for sewage contamination.

Quality Rain, day of (in) Prior Day 2 Days Prior 3 Days Prior Rain 4 Days Total Rain
Sort Sort Sort Sort Sort Sort Sort Sort
10/16/2023 96 Beach Advisory 0.0 0.0 0.7 0.0 0.8
09/18/2023 4611 Beach Advisory 0.6 0.1 0.0 0.0 0.7
08/21/2023 85 Beach Advisory 0.0 0.0 0.0 1.6 1.6
07/17/2023 583 Beach Advisory 0.0 0.1 0.2 0.1 0.4
06/26/2023 <10 Acceptable 0.0 0.0 0.1 0.0 0.1
05/01/2023 6867 Beach Advisory 3.1 1.1 1.7 0.0 6.0
10/10/2022 20 Acceptable 0.0 0.0 0.0 0.1 0.1
09/10/2022 <10 Acceptable 0.0 0.0 1.1 0.1 1.2
08/12/2022 20 Acceptable 0.1 0.1 0.0 0.6 0.8
07/15/2022 171 Beach Advisory 0.0 0.0 0.0 0.0 0.0
06/13/2022 168 Beach Advisory 0.3 0.0 0.0 0.7 1.0
05/23/2022 20 Acceptable 0.0 0.4 0.0 0.7 1.2
10/25/2021 121 Beach Advisory 0.0 0.0 0.0 0.0 0.0
09/13/2021 10 Acceptable 0.0 0.0 0.0 0.1 0.1
08/16/2021 10 Acceptable 0.0 0.0 0.0 0.0 0.0
07/19/2021 10 Acceptable 0.0 0.6 0.0 0.0 0.6
06/07/2021 31 Acceptable 0.0 0.0 0.7 0.3 1.0
05/17/2021 10 Acceptable 0.0 0.0 0.0 0.0 0.0
10/14/2020 20 Acceptable 0.0 0.9 0.2 0.0 1.1
09/18/2020 20 Acceptable 0.0 0.0 0.0 0.0 0.0
08/14/2020 20 Acceptable 0.1 1.5 0.0 0.0 1.6
07/14/2020 <10 Acceptable 0.0 0.1 0.0 2.5 2.6
06/16/2020 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
05/26/2020 10 Acceptable 0.0 0.0 0.0 0.8 0.8
10/08/2019 185 Beach Advisory 0.0 0.2 0.0 0.0 0.2
09/10/2019 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
08/06/2019 20 Acceptable 0.0 0.0 0.0 0.2 0.3
07/09/2019 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
06/04/2019 288 Beach Advisory 0.0 0.0 0.3 0.0 0.3
05/07/2019 96 Beach Advisory 0.1 0.0 1.3 0.1 1.5
10/10/2018 10 Acceptable 0.0 0.0 0.0 0.0 0.0
09/10/2018 465 Beach Advisory 0.9 0.5 0.0 0.0 1.4
08/14/2018 414 Beach Advisory 0.0 0.7 0.0 2.9 3.6
07/17/2018 30 Acceptable 0.0 0.0 0.6 0.4 1.0
06/13/2018 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
05/06/2018 20 Acceptable 0.0 0.0 0.0 0.0 0.0
10/16/2017 10 Acceptable 0.0 0.0 0.1 0.0 0.1
09/11/2017 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
08/14/2017 <10 Acceptable 0.0 0.0 0.1 0.0 0.1
07/10/2017 52 Acceptable 0.0 0.0 0.0 1.8 1.8
06/12/2017 10 Acceptable 0.0 0.0 0.0 0.0 0.0
05/15/2017 155 Beach Advisory 0.0 0.0 1.6 0.0 1.6
04/04/2017 884 Beach Advisory 1.2 0.0 0.0 0.0 1.2
10/13/2016 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
09/14/2016 10 Acceptable 0.0 0.0 0.0 0.0 0.0
08/15/2016 20 Acceptable 0.0 0.1 0.0 0.3 0.4
07/13/2016 10 Acceptable 0.0 0.0 0.0 0.0 0.0
06/15/2016 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
05/20/2016 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
10/12/2015 52 Acceptable 0.0 0.0 0.0 0.9 0.9
09/11/2015 1187 Beach Advisory 0.0 1.6 0.0 0.0 1.6
08/12/2015 231 Beach Advisory 0.0 1.2 0.0 0.0 1.2
07/08/2015 10 Acceptable 0.0 0.1 0.0 0.0 0.1
06/11/2015 <10 Acceptable 0.0 0.0 0.0 0.1 0.1
05/12/2015 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
10/13/2014 10 Acceptable 0.0 0.0 0.3 0.0 0.3
09/07/2014 <10 Acceptable 0.0 0.1 0.0 0.0 0.1
08/11/2014 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
07/07/2014 <10 Acceptable 0.0 0.0 0.0 0.1 0.1
06/12/2014 10 Acceptable 0.0 0.0 0.0 1.6 1.6
05/12/2014 109 Beach Advisory 0.0 0.0 0.4 0.0 0.4
10/16/2013 10 Acceptable 0.0 0.0 0.0 0.0 0.0
09/18/2013 20 Acceptable 0.0 0.0 0.0 0.0 0.0
08/14/2013 173 Beach Advisory 0.0 0.9 0.1 0.0 0.9
07/17/2013 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
06/19/2013 <10 Acceptable 0.0 0.2 0.0 0.0 0.2
05/31/2013 10 Acceptable 0.0 0.0 0.0 0.5 0.5
10/10/2012 20 Acceptable 0.3 0.0 0.0 0.2 0.5
09/10/2012 10 Acceptable 0.0 0.0 0.4 0.0 0.4
08/13/2012 <10 Acceptable 0.0 0.0 0.0 0.2 0.2
07/16/2012 10 Acceptable 0.0 0.3 0.0 0.0 0.3
06/11/2012 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
05/15/2012 <10 Acceptable 0.5 0.0 0.0 0.0 0.5
10/21/2011 52 Acceptable 0.0 0.0 1.1 0.0 1.1
09/14/2011 41 Acceptable 0.0 0.0 0.0 0.0 0.0
08/16/2011 565 Beach Advisory 0.0 0.6 5.8 0.0 6.4
07/19/2011 30 Acceptable 0.0 0.1 0.0 0.0 0.1
06/27/2011 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
05/16/2011 448 Beach Advisory 0.2 0.9 0.0 0.0 1.1
10/12/2010 487 Beach Advisory 0.1 1.1 0.0 0.0 1.2
09/11/2010 10 Acceptable 0.0 0.0 0.0 0.0 0.0
08/17/2010 63 Beach Advisory 0.0 0.1 0.2 0.0 0.3
07/21/2010 <10 Acceptable 0.0 0.0 0.1 0.0 0.1
06/15/2010 <10 Acceptable 0.0 0.0 0.3 0.0 0.3
05/21/2010 10 Acceptable 0.0 0.0 0.0 1.1 1.1
10/19/2009 10 Acceptable 0.0 0.3 0.0 0.1 0.4
09/14/2009 <10 Acceptable 0.0 0.0 0.0 0.8 0.9
08/20/2009 20 Acceptable 0.0 0.0 0.6 0.0 0.6
07/28/2009 399 Beach Advisory 0.0 0.6 1.4 0.0 2.0
06/22/2009 85 Beach Advisory 0.0 0.5 0.3 0.0 0.7
06/05/2009 448 Beach Advisory 0.9 0.5 0.5 0.1 2.0
05/12/2009 20 Acceptable 0.0 0.0 0.0 0.6 0.6
10/20/2008 10 Acceptable 0.0 0.0 0.0 0.0 0.0
09/24/2008 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
08/19/2008 <10 Acceptable 0.0 0.0 0.0 0.0 0.0
07/14/2008 5635 Beach Advisory 0.5 0.0 0.0 0.0 0.5
07/02/2008 10 Acceptable 0.0 0.0 0.0 0.6 0.6
06/24/2008 160 Beach Advisory 0.0 0.1 0.1 0.0 0.1
05/19/2008 10 Acceptable 0.0 0.1 0.0 0.9 1.1
09/06/2007 4 Acceptable 0.0 0.0 0.0 0.0 0.0
08/16/2007 19 Acceptable 0.0 0.0 0.0 0.0 0.0
07/11/2007 11 Acceptable 0.0 0.0 0.0 0.0 0.0
06/18/2007 16 Acceptable 0.0 0.0 0.0 0.0 0.0
05/23/2007 3 Acceptable 0.0 0.0 0.0 0.0 0.0
04/18/2007 356 Beach Advisory 0.0 0.0 0.9 7.6 8.5
11/10/2006 310 Beach Advisory 0.0 0.0 3.6 0.0 3.6
10/18/2006 263 Beach Advisory 0.0 1.1 0.0 0.0 1.1
09/26/2006 25 Acceptable 0.0 0.0 0.0 0.1 0.1

Entero Count (fecal indicator) and Rainfall Correlation

108 Samples taken

All Water Quality Parameters

108 Samples taken

Sample Date [i] Entero Count
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Entero Count

Enterococcus (“Entero”) is a fecal indicating bacterium that lives in the intestines of humans and other warm-blooded animals. It is the EPA preferred indicator for sewage contamination.

Quality [i] Temp (f)
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Temperature

Hudson River water temperature changes seasonally. Surface water temperature can change on small scales in the river reflecting natural and human influences.

[i] Salinity
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Salinity

Estuaries like the Hudson are where freshwaters in rivers meet the sea. Salinity tells us about the relative contribution of fresh and salt water within a particular region of the estuary. 

[i] Chlorophyll
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Chlorophyll

A measure of the amount of microscopic algae present in the water. High chlorophyll counts can mean high levels of the nutrients phosphorus and nitrogen, and the threat, or presence, of algae blooms.

[i] Turbidity
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Turbidity

Turbidity is a measure of the amount of fine particles suspended in the water. As turbidity rises, light penetration, a key factor for aquatic plants and algae, diminishes.

[i] Oxygen
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Oxygen

Oxygen concentrations in the water are closely connected to biological activities. Surface waters are typically in equilibrium with the atmosphere such that the oxygen concentration near the surface is close to fully saturated (100%).

Sort Sort Sort Sort Sort Sort Sort Sort
10/16/2023 96 Beach Advisory 17.21 15.25 0.95 9.5 91.4
09/18/2023 4611 Beach Advisory 22.55 19.61 1.55 1.1 66.7
08/21/2023 85 Beach Advisory 23.54 17.7 1.76 16.7 64.7
07/17/2023 583 Beach Advisory 25.69 5.51 2.3 18.7 73.1
06/26/2023 <10 Acceptable 68.6 23.1 2.1 6.7 72.5
05/01/2023 6867 Beach Advisory 54.3 12.4 1.6 12.3 80.0
10/10/2022 20 Acceptable 62 18.2 1.4 5.4 76.5
09/10/2022 <10 Acceptable 76.8 19.8 2.1 6.8 63.7
08/12/2022 20 Acceptable 78.7 18.8 2.4 5.9 66.7
07/15/2022 171 Beach Advisory 74 20.6 2.1 17.5 72.1
06/13/2022 168 Beach Advisory 69 14.2 2.6 13.7 82.4
05/23/2022 20 Acceptable 60.3 21.5 1.4 7.9 77.6
10/25/2021 121 Beach Advisory 64.256 20.38 1.62 7.9 n/a
09/13/2021 10 Acceptable 73.058 21.79 1.94 3.9 66.8
08/16/2021 10 Acceptable 75.074 23.84 1.88 11.3 56.2
07/19/2021 10 Acceptable 75.83 18.38 1.68 7.7 59.9
06/07/2021 31 Acceptable 65.624 18.51 1.06 9.7 71.6
05/17/2021 10 Acceptable 56.984 20.32 1.25 10.5 81.3
10/14/2020 20 Acceptable 63.122 23.24 1.43 3.2 76.2
09/18/2020 20 Acceptable 72.212 18.66 1.83 7.7 64.9
08/14/2020 20 Acceptable 77.882 23.41 1.52 4.3 51.9
07/14/2020 <10 Acceptable 76.676 22.87 1.66 4.6 63.2
06/16/2020 <10 Acceptable 68.846 16.93 2 3.6 85.4
05/26/2020 10 Acceptable 60.566 17.41 1.95 15.7 90.7
10/08/2019 185 Beach Advisory 67.712 22.9 1.47 2.4 73.5
09/10/2019 <10 Acceptable 73.094 21.23 2.54 3.2 69.8
08/06/2019 20 Acceptable 74.75 23.15 1.59 5.7 47.9
07/09/2019 <10 Acceptable 71.204 22.03 1.34 7.3 63.7
06/04/2019 288 Beach Advisory 63.68 12.23 1.54 23.8 77.9
05/07/2019 96 Beach Advisory 54.986 12.03 1.8 28.3 84.2
10/10/2018 10 Acceptable 70.646 6.22 2.2 16.7 75
09/10/2018 465 Beach Advisory 73.886 22.43 1.81 6.3 65.8
08/14/2018 414 Beach Advisory 76.604 20.26 1.35 12.9 46.1
07/17/2018 30 Acceptable 77.234 17.78 4.12 8.8 68.3
06/13/2018 <10 Acceptable 67.424 15.36 8.2 11.3 94.7
05/06/2018 20 Acceptable 53.528 13.43 4.51 14.8 92.6
10/16/2017 10 Acceptable 68.414 20.26 1.82 4.2 74.6
09/11/2017 <10 Acceptable 69.638 22.66 1.76 7.6 69.7
08/14/2017 <10 Acceptable 74.732 22.53 2.08 6.8 55.6
07/10/2017 52 Acceptable 73.058 13.52 1.17 16.1 74.8
06/12/2017 10 Acceptable 66.848 13.84 1.52 17.2 79.4
05/15/2017 155 Beach Advisory 55.94 15.17 1.72 14.2 83.4
04/04/2017 884 Beach Advisory 43.826 17.32 10.85 11.2 96.9
10/13/2016 <10 Acceptable 66.308 24.61 2.33 35.8 79.9
09/14/2016 10 Acceptable 76.712 17.05 4.77 n/a 79.1
08/15/2016 20 Acceptable 81.878 16.31 7.03 24.4 86.8
07/13/2016 10 Acceptable 74.876 19.03 3.54 5.8 75.5
06/15/2016 <10 Acceptable 67.316 17.54 2.18 16.2 83.3
05/20/2016 <10 Acceptable 57.884 18.6 1.81 n/a 87
10/12/2015 52 Acceptable 65.66 14.43 2 20 78.8
09/11/2015 1187 Beach Advisory 76.73 22.19 2.4 9.1 52
08/12/2015 231 Beach Advisory 76.046 16.95 2.48 10.4 68.9
07/08/2015 10 Acceptable 71.852 21.37 2.82 11.4 69.8
06/11/2015 <10 Acceptable 66.29 21.39 1.34 n/a 71.7
05/12/2015 <10 Acceptable 58.082 22.35 3.35 31.7 95.4
10/13/2014 10 Acceptable 64.652 23.99 1.2 14.2 74.1
09/07/2014 <10 Acceptable 76.28 21.62 2.82 7.6 68.1
08/11/2014 <10 Acceptable 76.424 17.01 1.6 16 67.8
07/07/2014 <10 Acceptable 70.97 18.82 1.64 6.6 67.2
06/12/2014 10 Acceptable 64.436 18.7 6.8 17.9 82.2
05/12/2014 109 Beach Advisory 56.444 15.11 2.33 18.8 90.4
10/16/2013 10 Acceptable 65.498 24.04 1 4.8 77.4
09/18/2013 20 Acceptable 69.764 24.59 2.46 n/a 69.6
08/14/2013 173 Beach Advisory 73.094 23.08 1.94 15.6 55
07/17/2013 <10 Acceptable 74.048 21.63 2.16 25.3 65.7
06/19/2013 <10 Acceptable 67.442 17.82 1.5 19.4 73.2
05/31/2013 10 Acceptable 63.14 20.29 1.09 7.4 74
10/10/2012 20 Acceptable 66.308 22.42 2.14 6.6 66.9
09/10/2012 10 Acceptable 76.784 24.06 2.59 22.5 53.7
08/13/2012 <10 Acceptable 78.134 31.72 0.9 14.1 56.2
07/16/2012 10 Acceptable 77.108 30.84 2.21 5.6 67.8
06/11/2012 <10 Acceptable 68.558 21.67 1.64 n/a 66.3
05/15/2012 <10 Acceptable 59.864 17.35 2.03 7.5 83.8
10/21/2011 52 Acceptable 63.302 16.78 0.64 24.6 76.4
09/14/2011 41 Acceptable 71.168 1.85 1.95 197.8 76.7
08/16/2011 565 Beach Advisory 74.984 19.65 0.99 24.5 41.9
07/19/2011 30 Acceptable 74.516 20.65 1.63 16.8 66.4
06/27/2011 <10 Acceptable 71.132 17.84 1.93 11.8 65.5
05/16/2011 448 Beach Advisory 57.236 11.33 2.27 65.8 81.4
10/12/2010 487 Beach Advisory 65.858 19.74 1.59 13.8 69.9
09/11/2010 10 Acceptable 72.194 22.2 1.51 19.4 62.6
08/17/2010 63 Beach Advisory 75.848 26.01 1.95 5.6 45.9
07/21/2010 <10 Acceptable 77.9 25.03 1.72 4.9 46.8
06/15/2010 <10 Acceptable 66.956 21.11 0.4 23.9 62
05/21/2010 10 Acceptable 56.804 23.24 2.06 12.9 75.2
10/19/2009 10 Acceptable 56.408 14.74 1.14 17.9 83.6
09/14/2009 <10 Acceptable 71.348 23.93 0.64 36 64.2
08/20/2009 20 Acceptable 78.152 15.86 1.97 20.4 62.6
07/28/2009 399 Beach Advisory 73.85 21.5 1.07 8.3 51.1
06/22/2009 85 Beach Advisory 69.53 5.87 1.01 68.9 75
06/05/2009 448 Beach Advisory n/a n/a n/a n/a n/a
05/12/2009 20 Acceptable 58.712 12.93 0.68 22.5 77.9
10/20/2008 10 Acceptable 61.88 25.37 0.84 6 70.2
09/24/2008 <10 Acceptable 70.1 24.45 5.1 7.7 82.5
08/19/2008 <10 Acceptable 75.7 16.06 1.22 17.4 64.3
07/14/2008 5635 Beach Advisory 74.138 21 1.37 11.3 64.6
07/02/2008 10 Acceptable 72.86 18.69 1.78 12 69
06/24/2008 160 Beach Advisory 69.404 22.5 0.97 8.7 63.5
05/19/2008 10 Acceptable 58.37 10 1.13 63.4 86.6
09/06/2007 4 Acceptable 73.562 24.925 1.37 10.05 58.65
08/16/2007 19 Acceptable 77.162 19.05 1.35 22.9 59
07/11/2007 11 Acceptable 70.52 24.75 1.09 20.8 57.3
06/18/2007 16 Acceptable n/a n/a n/a n/a n/a
05/23/2007 3 Acceptable 60.08 20.75 1.155 15.25 74.7
04/18/2007 356 Beach Advisory 44.996 12.55 0.12 16.9 95.5
11/10/2006 310 Beach Advisory 53.438 3.28 1.23 51.6 91.9
10/18/2006 263 Beach Advisory 63.536 21.92 1.14 8.9 69.2
09/26/2006 25 Acceptable 69.962 11.12 0.64 n/a 84.5

Water Quality*

Acceptable (0–60) Beach Advisory (61+)

*Single sample thresholds;
Enterococcus count per 100mL

Prior Four Day Rainfall
(in inches)

Dry Weather (0–0.25) Wet Weather (0.25+)

Enterococcus is an EPA-approved fecal contamination indicator.

Samples taken by Riverkeeper, Lamont-Doherty Earth Observatory and CUNY Queens College staff, and processed on the Riverkeeper vessel, according to the 2014 Quality Assurance Project Plan.

Rainfall data comes from wunderground.com. Wet weather is a common trigger of fecal contamination.

What do the Numbers Mean?

Water Quality scoring is based on the 2012 Recreational Water Quality Criteria from the US Environmental Protection Agency (EPA) for safe swimming. Learn More

About this location:

Bronx, NY
The Harlem River at the Willis Avenue Bridge is an industrial waterway, connecting the Hudson with the East River. Contact includes recreational boating and jet-skiing, kayaking, as well as recreational and subsistence fishing from the shore.

The data displayed on these pages relates to the levels of sewage indicating microbes. Even though the levels on a single days can fall within acceptable levels for Enterococcus, these locations are not necessarily acceptable for swimming. Other water quality parameters not reported on this web site such as chemical contamination and floatables should cause users to exercise caution at this site.

Agencies Responsible:

NYCDEP: 212-639-9675 and NYSDEC Region 2: 718-482-4933

Tell Gov. Hochul to block invasive species at the Erie and Champlain canals
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