Water Quality > Tributary and Waterfront Data > Pocantico River > Sleepy Hollow- Rockefeller Brook tributary

Sleepy Hollow- Rockefeller Brook tributary

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

28 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
10/27/20182310Beach Advisory0.
09/15/201874Beach Advisory0.
08/18/201819863Beach Advisory0.
06/16/2018157Beach Advisory0.
05/19/2018204Beach Advisory0.
09/16/2017770Beach Advisory0.
08/19/20171986Beach Advisory0.
07/15/20172420Beach Advisory0.
06/17/20172420Beach Advisory0.
10/08/2016178Beach Advisory0.
09/10/2016>2420Beach Advisory0.
08/13/20161986Beach Advisory0.
07/09/20162420Beach Advisory0.
06/11/2016328Beach Advisory0.
10/03/2015>2420Beach Advisory0.
08/01/2015575Beach Advisory0.
07/04/2015613Beach Advisory0.
06/06/2015488Beach Advisory0.
10/04/2014>2420Beach Advisory0.
09/06/2014517Beach Advisory0.
08/02/2014921Beach Advisory0.
07/05/20142420Beach Advisory0.
06/07/2014281Beach Advisory0.

Entero Count (fecal indicator) and Rainfall Correlation

28 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 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:

The Rockefeller Brook rises from three small ponds and flows through a mostly forested and agricultural area before joining the Pocantico River in the Rockefeller State Park Preserve.

Agencies Responsible:

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

Keep the Hudson River flowing!
Become a Member