Why bird sh*t shut down Pittsburgh’s drinking water

The straight ? on droppings and reservoirs

Roman Cherednychenko / Flickr

On Thursday, Pittsburgh Water and Sewer Authority lifted a boil and flush advisory for customers in northern Pittsburgh neighborhoods and Reserve Township. The advisory remains in effect for residents of Millvale, with water test results still pending there.

The advisory itself was first put in place Monday after abnormal test readings at the Lanpher Reservoir. They were also put in place amid concerns about a tear in the reservoir’s cover that “could compromise water quality” by leaving the water vulnerable to animal and bird droppings containing bacteria or pathogens dangerous to humans.

But given that not all water supplies are covered, what made this different? Rachel Rampa, PWSA assistant communications director, explained via email.

Q: How did bird waste factor into this boil advisory? Potable water can be drawn from rivers and open reservoirs, so why did it matter this time?

A: “EPA mandates require that all open reservoirs containing drinking water be covered or undergo additional retreatment processes to protect drinking water from biological pathogens.

“All of PWSA’s reservoirs are covered, except Highland Reservoir 1. That open reservoir has an additional microfiltration plant connected to it that performs a full second water treatment process to protect it from biological pathogens before entering the distribution system. (Lanpher Reservoir, by comparison, undergoes no such retreatment process.) Bird waste can contain such biological pathogens; therefore, if any breach is detected in a cover, or treatment process to an open reservoir, a precautionary boil water advisory is issued until all water going through the system can be tested multiple times to confirm there are no contaminants present.

“Since the inspection of the Lanpher cover Monday morning, Aug. 28 determined that the cover may be compromised, the potential for untreated water to enter the reservoir exists. The boil water advisory was issued per the standard Department of Environmental Protection process to ensure that all drinking water meets regulatory standards before lifting the advisory.”

Q: So is there an allowable amount of animal droppings in water supplies?

A: “There is no such allowance; bird waste should not and does not exist in any drinking water, because the water is treated and chlorinated to remove any contaminants or waste before it enters the distribution system.”