NEW YORK (AP) – A state regulatory agency on Wednesday released a blistering report on a blackout that left tens of thousands of people without power for a week last summer, charging the local utility’s performance was “unacceptable and a gross disservice to its customers.”

The 185-page Public Service Commission report details a litany of mistakes that Consolidated Edison made during the blackout in July 2006 and said the company needed to make “critical and substantial” improvements.

The report said about 174,000 people in Queens lost service or experienced low voltage, many more than the 100,000 that Con Ed claimed in the wake of the outage, which began July 17. The report did not find any evidence that the company had spent less money on its operations in the borough, which is home to many of the city’s largest immigrant communities, than it did in other areas.

The commission said it only found incompetence – plenty of it.

“In general, staff found that Con Edison’s overall performance was poor and unreasonable,” said the draft report by the PSC’s staff, which began investigating the day after power was restored on July 25. “Staff finds that Con Edison’s performance was unacceptable and a gross disservice to its customers.

At the height of the crisis, 10 of the 22 feeder cables that carry electricity through the Co Ed system were malfunctioning. Residents sweltered without air conditioners on some of the hottest days of the years, and estimated business losses ran into the tens of millions of dollars as stores were forced to throw out perished goods.

In October, Con Edison, in its own report, praised its efforts to restore power, detailing how it was quick to respond by deploying all available personnel on an around-the-clock basis.

But the PSC report said: “While most of the company’s operating personnel, field crews and consumer services representatives worked long hours and under difficult conditions to contain the crisis, the company either failed, or refused, to comprehend the magnitude of the crisis.”

Consolidated Edison said Wednesday it has worked tirelessly to improve its network systems, operating performance and emergency response procedures. It said it was reviewing the PSC’s preliminary findings.

“We will continue to improve our operations and procedures to reduce the likelihood of similar occurrences in the future and will continue to work closely with city and state agencies,” it said in a statement.

Equipment failures and customer outages beset Con Ed’s network in the Long Island City section of Queens and in Westchester County after temperatures in the 90s engulfed the region in a suffocating heat wave.

Con Edison said the blackout was caused by three unrelated incidents, but the commission disputed that finding in one particularly damning section of the report, suggesting that the scope of the disaster could have been reduced if company officials had take action previously.

“The overriding cause of the Long Island City network event and the lengthy outage was the company’s failure to address a multitude of pre-existing problems and issues associated with the operations, maintenance and oversight of the Long Island City network and its failure to shut the network down in light of glaring evidence that the secondary system was experiencing severe damage during the early stages of the event,” the report said.

PSC staff investigators also chided the company for not creating an effective way to assess damages or outages, calling it a “major failure.” They said company officials “ignored many indications that the outage was significantly more widespread and damaging than they thought.”

The commission accused the company of providing inaccurate information to its customers, public officials and the media, “compromising public safety.”

The report said Con Edison had spent an estimated $120 million in connection with the blackout, but apparently that’s not enough. It found “significant weakness” in Con Edison’s “system and practices that could lead to similar or worse problems in the future if not corrected now.”