Sleepy Hollow- DEP Spillway

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

42 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
10/27/20182603Beach Advisory0.
09/15/2018195Beach Advisory0.
08/18/2018>24196Beach Advisory0.
06/16/2018629Beach Advisory0.
05/19/2018>2420Beach Advisory0.
09/16/2017866Beach Advisory0.
08/19/20171414Beach Advisory0.
07/15/20172420Beach Advisory0.
06/17/2017313Beach Advisory0.
05/20/2017104Beach Advisory0.
10/08/2016436Beach Advisory0.
09/10/20162420Beach Advisory0.
08/13/20161986Beach Advisory0.
07/09/20161414Beach Advisory0.
06/11/2016285Beach Advisory0.
05/14/201663Beach Advisory0.
10/03/2015>2420Beach Advisory0.
09/05/20151986Beach Advisory0.
08/01/2015770Beach Advisory0.
07/04/2015687Beach Advisory0.
06/06/20151733Beach Advisory0.
10/04/2014>2420Beach Advisory0.
09/06/201471Beach Advisory0.
08/02/2014326Beach Advisory0.
07/05/20141986Beach Advisory0.
06/07/2014152Beach Advisory0.
10/12/201366Beach Advisory0.
09/14/20131414Beach Advisory0.
08/10/2013158Beach Advisory0.
07/13/20131733Beach Advisory0.
06/15/2013178Beach Advisory0.
05/04/2013326Beach Advisory0.
10/06/20121046Beach Advisory0.
09/08/2012>2420Beach Advisory1.
08/04/2012130Beach Advisory0.
07/14/2012>2420Beach Advisory0.
06/02/2012>2420Beach Advisory0.
11/06/2011167Beach Advisory0.

Entero Count (fecal indicator) and Rainfall Correlation

42 Samples taken

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 citizen scientists trained by Riverkeeper, and processed on the Riverkeeper vessel, according to the 2014 Quality Assurance Project Plan.

Rainfall data comes from 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:

This site is located at a NYC DEP building that is part of the Croton aqueduct system. The site is near Rockefeller Brook.

Agencies Responsible:

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

Keep the Hudson River flowing!
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