What We Learned From Summer E. coli Monitoring

Primrose Brook in Jockey Hollow continues to have low E. coli during all but the heaviest rains. Credit GSWA/A. Ostella. 6/24/2015

Primrose Brook in Jockey Hollow continues to have low E. coli during all but the heaviest rains. Credit GSWA/A. Ostella. 6/24/2015

After five weeks in a row of sample collection, we have completed our E. coli monitoring program. Many thanks to the 11 volunteers involved; this program would not happen with you!

Last year, we were able to delineate sites based on when they met NJDEP’s strict water quality standards in both wet (storm) and dry (baseflow) conditions.* This year’s results are not as easy to categorize. Here is what we have learned:

  • Sites in ponds or just downstream from ponds had lower E. coli. Kitchell Pond in Loantaka Brook Reservation is the only location where we sampled both immediately upstream and immediately downstream of a pond. The downstream site (LB2M) was significantly lower than the upstream site (LB3) during 4 out of 5 weeks. Other ponds with frequently low E. coli levels, including Foote’s Pond in Morristown, Bayne Pond in Harding, and Branta Pond at the Somerset County Environmental Education Center.
  • Sites in Morristown National Historical Park at Jockey Hollow remain healthy with low levels of E. coli during all but the heaviest rains.
  • Four sites exceeded the state standard for all five weeks of testing: (a) LB5 and (b) LB4M in Loantaka Brook near Woodland Ave. and Ginty Pool in Morris Township, (c) BB2VA in Black Brook by Tanglewood Ln. in Chatham Township, and (d) CMA2 in Silver Brook in GSWA’s Conservation Management Area.
Silver Brook upstream from the big bridge in the CMA. Credit: GSWA/ J. Webb. 6/24/2015

Silver Brook upstream from the big bridge in the CMA. Credit: GSWA/ J. Webb. 6/24/15

So what does it all mean? Keep an eye on this blog as we decipher some of the findings!

Click here for 2015 E. coli results and click here for a map of the sites.

*Based on last year’s results, “storm conditions” were present when there was 0.25” of rain or more within the 48 hours prior to sample collection. “Baseflow conditions” were present if there was less than 0.25” of rain during that time period.


Leave a Reply

Your email address will not be published. Required fields are marked *