Pepco Region President Thomas Graham thanked customers for their patience, 46 days after more than 480,000 Pepco customers lost power -- some for more than a week -- following the June 29 derecho.

In a letter that arrived in customers' mailboxes this week, Graham touted the company's force of more than 3,000 workers who were involved in restoring power in the days following the storm and emphasized the destructive force of the derecho, a type of storm that gets its name from its straight-line winds.

"Yet even with all of the destruction, Pepco restored power to 90 [percent] of customers by midnight on July 4, more than 48 hours before our original estimate," Graham wrote. "We reached 100 [percent] restoration before any other utility in the area -- just before dawn on Sunday, July 8."

Pepco's post-storm performance has been widely criticized. At a hearing held by the Public Service Commission, some residents were particularly incensed by public relations maneuvers like Graham's letter after what they felt was particularly poor performance.

But according to Graham, not every resident felt the same.

"I would also like to thank customers who took time to show their gratitude -- shaking crew members' hands, and leaving them notes, water and Popsicles, and even sending emails or handwritten thank you notes to the company," he wrote at the end of the letter.