Tibbetts Brook Water Quality Monitoring

Urban park wetlands, lakes, streams and ponds are hosts to a number of ecological stressors leading to increased deposition of nutrients, road salt, sediment and invasive species (Dudgeon et. al. 2006). Tibbetts Brook is one of the last above ground streams left in NYC due to development. Since December of 2015 the Friends in association with the Civil & Environmental Engineering Department at Manhattan College have been monitoring the health of Tibbetts Brook and the associated Van Cortlandt Lake in order to better understand human impacts on the aquatic system.

If you are interested in joining our Water Monitoring team, contact John Butler, Ecological Project Manager, at john@vancortlandt.org for future dates.

Monitoring Sites Map


Project highlights thus far

  • The monitoring team was successful in sampling once a week in the brook for one year, while teaching over 70 community members water quality monitoring strategies. We are happy to announce that we are continuing monitoring Tibbetts Brook in 2017 and would love your help!
  • In June of this past year, while in the field, the monitoring team observed a small localized fish kill directly nearby a storm water pipe from I-87 that leads directly into the Lake. Both the NYC Parks Department and the DEC were contacted, and although nothing was determined, it has begun to draw attention to the three storm water pipes that enter the eastern side of Van Cortlandt Lake from I-87.
  • A groundwater discharge enters the Tibbetts Brook system nearby the John Kieran Nature Trail repeatedly has high conductivity, common in groundwater, but also held high levels of Enterococcus and Fecal Coliform bacteria when tested last summer.
  • The Friends were led to a suspicious storm water pipe along the South County Trail in Yonkers. This pipe was brought to the attention of the Department of Environmental Conservation and Yonkers Engineering Department during the month of August 2016. With further probing, Yonkers Engineering found three illegal connections and multiple sewage leaks into this pipe, allowing raw sewage to enter Tibbetts Brook, and eventually to Van Cortlandt Lake. As the illegal connections and sewage leakages are fixed in Yonkers, bacteria levels in the Brook will hopefully decrease.


Suggested Readings

Dudgeon, David, et al. “Freshwater biodiversity: importance, threats, status and conservation challenges.” Biological reviews 81.02 (2006): 163-182.

Wenger, Seth J., et al. “Twenty-six key research questions in urban stream ecology: an assessment of the state of the science.” Journal of the North American Benthological Society 28.4 (2009): 1080-1098.