So far, his office has received more than 7,900 complaints about the provincial utility's billing practices — and they keep pouring in, he said after releasing his annual report.
"We're still getting about 10 a day, which is quite incredible," Marin said.
His office has never received so many complaints about a single government organization, he said, pushing up the annual total to a record 26,999 complaints last year — a 37 per cent increase from the year before.
Marin launched an investigation in February after customers complained about delayed or missing invoices, which resulted in high "catch-up" bills.
Hydro One took $8,390 from the bank account of one woman who had authorized automatic payments, saying it had underestimated her billings for almost two years, his report said.
Other customers complained of unintelligible billing, erratic billing and overbilling, lack of meter readings and malfunctioning smart meters, he said.
"People whose homes have completely burned down and they're still getting hydro bills, which is my favourite one," he said.
"It's actually quite incredible ... for many of these people, it's been a hopeless quagmire."
Hydro One responded immediately after he announced the probe and have taken several short-term measures to alleviate problems, Marin said. He expects to release his report in November.
The Crown corporation said it has received 1,733 complaints from the ombudsman's office and has resolved 1,567 with customers. It said it is currently billing 99.2 per cent of its customers on actual usage.
Hydro One "would like its customers to know that we (have) been working tirelessly — and have made progress — to resolve the customer service issues currently before us," president and CEO Carmine Marcello said in a statement.
But Marin said he's skeptical. "I'm not sure where these numbers come from," he said.
His annual report also summarized other cases his office is working on, such as a probe into unlicensed daycares launched after the death of a two-year-old girl north of Toronto, which is expected to be released this summer.
It also looked at whether the government took any action in response to the office's previous work, such as non-emergency medical transfers. Marin said the Liberals did introduce legislation to address problems stemming from some of those cases, but those bills died when the June 12 election was called.
They included a bill aimed at replacing a controversial law that led to police arresting and detaining hundreds of people during the Toronto's G20 protests in 2010.
"I find it troublesome that it's still in the books," Marin said.
Now that the Liberals are coming back with a majority of seats in the legislature, government legislation should pass more quickly, he said.
Premier Kathleen Wynne has promised to re-introduce a bill that would give Marin a long-sought power to oversee municipalities, school boards and universities — but not hospitals.
It wasn't quite everything he had dreamed it would be, but it will allow Ontario to catch up with other provinces and the powers they've granted to their ombudsmen, Marin said.
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