Saw Mill River

Saw Mill River

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

77 Samples taken

Sample Date [i] Enterococcus Count

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.

QualityRain, day of (in)Prior Day2 Days Prior3 Days Prior Rain4 Days Total Rain
SortSortSortSortSortSortSortSort
09/10/201720Acceptable0.00.00.00.10.1
08/13/201752Acceptable0.00.40.30.00.8
07/09/2017134Beach Advisory0.00.02.20.02.2
06/11/2017<10Acceptable0.00.00.00.00.0
05/14/20171067Beach Advisory0.11.70.00.01.8
04/04/201720Acceptable1.10.00.00.11.2
10/12/201651Acceptable0.00.00.00.10.1
09/13/201620Acceptable0.00.00.00.20.2
08/14/2016<10Acceptable0.00.10.20.30.6
07/12/201610Acceptable0.00.00.00.80.8
06/14/2016<10Acceptable0.00.00.00.10.1
05/19/201663Beach Advisory0.00.00.00.00.0
10/11/2015688Beach Advisory0.00.00.10.00.1
09/10/20156488Beach Advisory1.30.00.00.01.3
08/11/201519863Beach Advisory1.00.00.00.01.0
07/07/2015<10Acceptable0.00.00.00.00.0
06/10/201552Acceptable0.00.20.20.00.4
05/11/201531Acceptable0.00.00.00.00.0
10/12/2014226Beach Advisory0.00.30.00.00.3
09/07/2014350Beach Advisory0.00.10.00.00.1
08/11/201463Beach Advisory0.00.00.00.00.0
07/07/2014<10Acceptable0.00.00.00.10.1
06/12/2014201Beach Advisory0.00.00.01.61.6
05/12/201475Beach Advisory0.00.00.40.00.4
10/16/201386Beach Advisory0.00.00.00.00.0
09/18/201341Acceptable0.00.00.00.00.0
08/14/2013959Beach Advisory0.00.90.10.01.0
07/17/201341Acceptable0.00.00.00.00.0
06/19/201331Acceptable0.00.20.00.00.2
05/31/2013121Beach Advisory0.00.00.00.50.5
11/08/2012134Beach Advisory0.11.10.00.01.2
10/10/2012<10Acceptable0.30.00.00.20.5
09/10/2012404Beach Advisory0.00.00.40.00.4
08/13/2012368Beach Advisory0.00.00.00.20.2
07/16/2012958Beach Advisory0.00.30.00.00.3
06/12/201298Beach Advisory0.00.00.00.00.0
05/16/201210Acceptable0.10.50.00.00.6
10/21/201131Acceptable0.00.01.10.01.1
09/15/201175Beach Advisory0.00.00.00.00.0
08/17/201124196Beach Advisory0.00.00.65.86.4
07/25/201119863Beach Advisory0.00.00.00.00.0
07/22/201110Acceptable0.00.00.00.00.0
07/21/2011<10Acceptable0.00.00.00.10.1
07/18/201110Acceptable0.00.00.00.00.0
06/28/2011959Beach Advisory0.00.00.00.00.0
05/17/2011>24196Beach Advisory0.70.20.90.01.8
10/13/2010816Beach Advisory0.00.11.10.01.2
09/12/2010<10Acceptable0.00.00.00.00.0
08/18/201085Beach Advisory0.00.00.10.20.3
07/22/20101274Beach Advisory0.00.00.00.10.1
06/16/201051Acceptable0.00.00.00.30.3
05/22/201041Acceptable0.00.00.00.00.0
10/19/2009148Beach Advisory0.00.30.00.10.4
09/15/2009<10Acceptable0.00.00.00.00.0
08/21/200910Acceptable0.00.00.00.60.6
07/29/200986Beach Advisory0.00.00.61.42.0
06/23/200920Acceptable0.00.00.50.30.8
06/06/200910Acceptable0.00.90.50.51.9
05/13/2009246Beach Advisory0.00.00.00.00.0
10/21/200810Acceptable0.00.00.00.00.0
10/20/200820Acceptable0.00.00.00.00.0
10/19/200810Acceptable0.00.00.00.00.0
09/23/200831Acceptable0.00.00.00.00.0
08/19/200820Acceptable0.00.00.00.00.0
07/14/20084229Beach Advisory0.50.00.00.00.5
07/02/20086488Beach Advisory0.00.00.00.60.6
06/24/20081427Beach Advisory0.00.10.10.00.2
05/19/2008109Beach Advisory0.00.10.00.91.0
09/06/2007123Beach Advisory0.00.00.00.00.0
08/16/2007134Beach Advisory0.00.00.00.00.0
07/11/200711Acceptable0.00.00.00.00.0
06/28/200711Acceptable0.00.70.00.00.7
06/18/200719Acceptable0.00.00.00.00.0
05/23/2007115Beach Advisory0.00.00.00.00.0
04/18/20071496Beach Advisory0.00.00.97.68.5
12/13/20061500Beach Advisory0.20.00.00.00.2
11/10/20061500Beach Advisory0.00.03.60.03.6

Entero Count (fecal indicator) and Rainfall Correlation

77 Samples taken

All Water Quality Parameters

77 Samples taken

Sample Date [i] Entero Count

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)

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

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

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

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

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%).

SortSortSortSortSortSortSortSort
09/10/201720Acceptable7111.22.514.678.9
08/13/201752Acceptable77.49.73.112.476.5
07/09/2017134Beach Advisory75.05.02.913.794.9
06/11/2017<10Acceptable68.12.9218.392.2
05/14/20171067Beach Advisory54.40.45.023.099.7
04/04/201720Acceptable48.00.312.143.1100.0
10/12/201651Acceptable64.813.96.63191
09/13/201620Acceptable76.711.536.7n/a133
08/14/2016<10Acceptable83.88.851.516165
07/12/201610Acceptable77.29.68.2999
06/14/2016<10Acceptable68.77.54.92299
05/19/201663Beach Advisory59.36.42.8n/a96
10/11/2015688Beach Advisory65.913.333687
09/10/20156488Beach Advisory78.313.4101278
08/11/201519863Beach Advisory75.312.911.22185
07/07/2015<10Acceptable77.24.619.320100
06/10/201552Acceptablen/an/an/an/an/a
05/11/201531Acceptable66.85.62.82698
10/12/2014226Beach Advisory63.410.82.53584
09/07/2014350Beach Advisory7712.24.41981
08/11/201463Beach Advisory77.1103.82976
07/07/2014<10Acceptable76.33.3813100
06/12/2014201Beach Advisory66.58.432.119104
05/12/201475Beach Advisory59.1421898
10/16/201386Beach Advisory65.714.82.41580
09/18/201341Acceptable69.210.731880
08/14/2013959Beach Advisory757.464687
07/17/201341Acceptable79.95.74.52086
06/19/201331Acceptable69.22.44.22692
05/31/2013121Beach Advisory64.73.62.86889
11/08/2012134Beach Advisory50.78.51.12193
10/10/2012<10Acceptable64.98.55.7486
09/10/2012404Beach Advisory76.210.86.61384
08/13/2012368Beach Advisory80.712.214.88106
07/16/2012958Beach Advisory78.810.711.815100
06/12/201298Beach Advisory70.96.75.72585
05/16/201210Acceptable62.42.96.119100
10/21/201131Acceptable6221.34192
09/15/201175Beach Advisory710.21.815180
08/17/201124196Beach Advisory745.42.12787
07/25/201119863Beach Advisory81.85.623.39n/a
07/22/201110Acceptable84.85.432.218209
07/21/2011<10Acceptablen/an/an/an/an/a
07/18/201110Acceptable79.86.62.932n/a
06/28/2011959Beach Advisory76.83.715.3596
05/17/2011>24196Beach Advisory57.70.6n/an/a99
10/13/2010816Beach Advisory64.22.13.61886
09/12/2010<10Acceptable72.711.23.51570
08/18/201085Beach Advisory77.511.512987
07/22/20101274Beach Advisory79.39.424.127105
06/16/201051Acceptable7110.43.43473
05/22/201041Acceptable61.79.32.72487
10/19/2009148Beach Advisory54.491.92090
09/15/2009<10Acceptable71.69.72.55087
08/21/200910Acceptable80.18.36.73682
07/29/200986Beach Advisory77.25.73.32681
06/23/200920Acceptable70.41.30.83788
06/06/200910Acceptablen/an/an/an/an/a
05/13/2009246Beach Advisory59.12.21.21497
10/21/200810Acceptable59.712.12.31688
10/20/200820Acceptable61.715.41.91582
10/19/200810Acceptable62.217.51.63381
09/23/200831Acceptable69.910.621981
08/19/200820Acceptable77.68.62.31292
07/14/20084229Beach Advisory756.84.37193
07/02/20086488Beach Advisory759.56.33288
06/24/20081427Beach Advisory72.79.22.53086
05/19/2008109Beach Advisory59.15.91.55895
09/06/2007123Beach Advisory74.913.32.81783
08/16/2007134Beach Advisory78.911.73.34180
07/11/200711Acceptable76.412.67.21593
06/28/200711Acceptable74.8n/an/an/a96
06/18/200719Acceptablen/an/an/an/an/a
05/23/2007115Beach Advisory632.51.24993
04/18/20071496Beach Advisory42.80.40.57799
12/13/20061500Beach Advisory45.421.312100
11/10/20061500Beach Advisory53.81.31.54595

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:

Yonkers, NY
The Sawmill River enters the Hudson at Yonkers. There is boating, kayaking, recreational and subsistence fishing in this area.

Agencies Responsible:

Westchester County Dept. of Health: 914-813-5000 and NYSDEC Region 3: 914-428-2505

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