Chlorinated Water Being Dumped into Sligo
- DEP and MDE Reports -



Kathy Michels
January 11, 2006 		Original Posting
January 10, 2006 		WSSC Explanation
January 21, 2006 		FoSC Members Timelines
January 22, 2006
Letter to WSSC from FoSC
January 24, 2006 		WSSC Response to FoSC Letter
February 9, 2006 		WSSC Report at FoSC Meeting
May 15, 2007


The damage to life in Sligo Creek is severe according to Cameron Wiegand of Montgomery County Department of Environmental Protection:

On Monday Jan. 9, 1:00 pm Monitoring staff returned from the field and reported the following impacts on Sligo Creek:

  • Fish and salamander kills within and downstream of the pond, downstream to the playground parking area immediately below University Boulevard
  • About 50 dead salamanders between the discharge location and the stormwater pond
  • DEP staff detected chlorine levels below the outfall
  • Absence of benthics in the stream from the discharge downstream to the vicinity of University Boulevard
  • Absence of algae in the stream downstream to the pond
  • Evidence of stains on the streambank, apparently from the residue of the attempted dechlorination activity.

Photos taken by DEP showing effects of chlorine discharge - PDF file

MDE REPORT - excerpt - Information as of January 10, 2006

Presence/ behavior of live fish:
OBSERVATIONS MADE FROM DENNIS AVENUE TO UNIVERSITY BOULEVARD:
Despite the fact that two days had passed since the discharge had stopped, several actively dying fish were observed. Also, dozens of chronically affected fish were observed swimming erratically but evasively. Hundreds of live apparently healthy fish were also observed in the affected area.
Presence/ types of aquatic invertebrates (order/ family/ relative abundance):
None observed by MDE. No crayfish were observed. Mont. DEP observed an unknown number of dead oligochaetes worms in the upper reaches of the stream, above the stormwater ponds. They observed live leaches in the same area.

Kill Information as of January 10, 2006:
Upper Limit: 0.5 miles u/s of University Boulevard
Lower Limit: approximately Dennis Avenue
Stream miles (lake acres) affected: 1.4 miles
Species affected Size # found killed
juvenile sunfish species 1-2" 93
blacknose dace -3.5" 76
bluegill sunfish 3-6" 47
fathead minnow 3" 4
creek chub 4-7" 4
rosyside dace 3" 2
green sunfish 2-4" 2
dusky salamander 2-4" 162
tadpole 2-3.5" 2

TOTAL (FISH ONLY): 228
Suspected cause of kill: chlorine toxicity
Kill total or selective: Not total. Effect on some fish was chronic, and some continue to die as of 01/10/2006.
Condition of dead fish: From fresh to early stages of decomposition. Symptoms of moribund fish: lethargic, laying on side, slowly gilling. One displayed mouth stuck open, with pectoral gills pointed out.
Additional Investigations: MDE's Water Management Administration continues to investigate enforcement options against WSSC. Montgomery County DEP also investigated upper portion of affected area. DEP field report received and included in file.