Larry Oliver, district chief with Front Royal Volunteer Fire and Rescue responded to the call Friday when they found 2,000 fish killed along with a raccoon and a possum.
Fire officials said the discharge was traced back to the Hydro Spray Car Wash on Commerce Avenue.
"He did observe that crayfish were not impacted and many other invertebrate, so that's what led him to believe that it was a detergent, and not some other material that may have been more detrimental to invertebrate life," said Steven Burke, Front Royal town manager.
Witnesses told police they saw a black pickup truck dumping materials at the car wash on Friday. The materials eventually reached a storm sewer on Fifth Street and ultimately, Happy Creek.
"Unfortunately, they simply chose an inappropriate and easy disposal location for whatever they were trying to get rid of," added Burke.
The fire department is investigating with the Virginia Department of Emergency Management and the Department of Environmental Quality. They said the discharge was between Fifth Street and north of Gertrude Miller Park where the material has now dissipated.
"I mean, sure, there's some type of environmental impact but in the long term, it's not going to be as big of an impact as it could've been, had it been another type of chemical or something like that," said Oliver.
Happy Creek is now safe again for recreational use and luckily the town's drinking water has not been affected.
The incident is still under investigation. Anyone with information about the black pickup truck is urged to contact Front Royal Police Department at (540)-635-2111.
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