SPOKANE, Wash. – A Spokane man is devastated after his dog was electrocuted in downtown Spokane due to an apparent heated sidewalk malfunction.   

Zach Harper was walking his dog, Hank, on a sidewalk outside of the Washington Trust Bank building’s parking garage on First Avenue on Tuesday when Hank appeared to suffer an electric shock. Hank died minutes later.

"My dog completely froze and then went straight into sounds I've never heard him make before," Harper told KREM 2. 

Harper said he thought Hank stepped on something. He reached for Hank, who bit his hand - something totally out of character for the young Border Collie/Australian Shepherd mix. 

Harper said the bank's building manager rushed to help and moved Hank to a different section of sidewalk, but Hank laid on the ground and started to go stiff. 

“I had to watch my 4-year-old, perfectly healthy, best friend of a dog, Hank pass away directly in front of me, and a crowd of others that were trying to help,” Harper wrote on Facebook. “At this point, what I do understand is that it was an absolute ‘freak accident’ and I don’t even know how to begin to describe was has happened, how I feel, or where I go from here. He was absolutely helpless…and it was so incredibly traumatic and sad to be part of.”

Harper said he reached for his phone, which had fallen behind Hank, and felt a jolt. 

"That's when I started to yell, 'I think it's something in the pavement,'" Harper said. 

Hank stopped breathing and despite Harper and others trying to administer CPR, Hank passed away. 

Harper said Washington Trust Bank’s Chief Operating Officer reached out directly to him and is trying to “make this right.”

Watch: Harper talks to KREM about tragic incident

Electrocution from 'stray voltage' in sidewalk

Harper said he and his veterinarian believe Hank was electrocuted by a heated sidewalk, which malfunctioned. They also believe moisture and rock salt may have also carried the electricity to Hank.

Washington Trust Bank and Avista also said the heated sidewalk was likely to blame. 

Washington Trust Bank released a statement about the incident to KREM 2.

“It appears the death was caused by stray voltage,” bank leaders said. “We are in close contact with Zach during this difficult time and are broken-hearted for his loss."

The bank doesn’t yet know exactly what caused the stray voltage, but said it has turned off all electricity outside of the building and tested the area to make sure it is safe.

“We are working with our building manager, Avista, and outside engineers to determine the cause of this tragedy. After we determine the cause we will then determine what next steps are to assure something like this never occurs again,” Washington Trust Bank leaders said.

Avista said it received a call from Harper Tuesday afternoon and immediately began to investigate. The power company said the electrocution appears to have been caused by the heated sidewalk malfunction. 

“We have worked collaboratively with Washington Trust Bank to investigate this matter, and we understand that the issue relates to a problem with WTB’s sidewalk heating equipment,” Avista officials said. “We have inspected all Avista equipment in the vicinity of where the incident occurred and determined it to be in safe working order.”

An Avista spokesperson told KREM 2 the sidewalk is Washington Trust Bank's heating system. The company does not regulate that system and could not say whether it owned other heated sidewalks in the city. 

The city of Spokane said it does not have an inventory of heated sidewalks downtown, and does not require special permits or inspections for heated sidewalks.  

RELATED: City of Spokane, Avista say heated sidewalks aren't regulated after dog's electrocution

Owner urges others to take precautions

Harper said he is sharing his story in hopes that other dog owners protect their pets from the same tragic outcome. 

"As crazy as it is to put little booties on your dog, if it's wet outside I would absolutely encourage that because you could potentially save a life," he said. 

Harper also cautioned owners from letting their pets step on or go to the bathroom on metal objects when it's wet outside. 

Harper says he has an amazing support system and has been overwhelmed by how many people reached out after Hank's death, but he's still in shock.

 "It's still a tough reality to settle with I guess, knowing that something like this could happen on a public sidewalk," he said. 

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