"The department remains committed to this investigation," Powell added, noting there is still a $10,000 reward for information leading to Susan Powell's whereabouts.
Anyone with information is encouraged to call the West Valley City Police Department at 801-840-4000.
In recent months, a spokesman for the city has said ongoing work on the case justifies their refusal to release records related to the investigation.
In Washington state, the Associated Press reported Wednesday it received a folder containing nearly 4,500 images of Susan Powell in response to a records request for evidence used at the voyeurism trial of Steve Powell, her father-in-law. Many of the images of Susan were taken without her knowledge and focused on her crotch and backside.
They were among other evidence seized from Steve Powell's Puyallup home in August 2011. Among that cache were images of young girls who lived next door, which were used to convict Steven Powell of voyeurism charges earlier this year.
Susan Powell was last seen at her home Dec. 6, 2009, a Sunday, when a friend stopped by to help the young mom untangle some yarn and then stayed through a later-afternoon pancake brunch.
A day-care provider raised an alarm early the next morning when the boys were not dropped off as scheduled and she could not reach either parent. Josh Powell, accompanied by the boys, finally arrived back at the couple's home in the early evening of Dec. 7, 2009. Josh Powell told police they had left around midnight to go camping in Utah's West Desert, while Susan stayed behind. He initially insisted he assumed she had gone to work.
But the story was full of holes from the moment Josh Powell offered it. Investigators found Susan Powell's cellphone in her husband's minivan, and Josh Powell could not explain why he called it after being informed his wife was missing. They identified her blood on a couch and nearby floor in the couple's home. They also retrieved a statement Susan Powell, 28, prepared detailing the couple's ongoing marital problems and her concerns that Josh Powell might harm her if she attempted to proceed with a divorce and sought custody of their sons.
The most innocent and telling observation of all came from Powell's son Charlie, who was 4 at the time his mom disappeared. Charlie told a police investigator his mom had gone camping with them but did not come back with them and he did not know why.
The story shifted to Washington when, less than a month after his wife's disappearance, Josh Powell, with his sons, moved into his father Steven's home in Puyallup.
The case simmered until August 2011 when police searched the Puyallup home looking for clues. A month later, they arrested Steven Powell and charged him with voyeurism after finding sexually explicit photos he had taken surreptitiously of neighborhood children.
Washington authorities removed the boys Charlie, 7, and Braden, 5 from the home and placed them with their grandparents. The Coxes were engaged in a custody battle with Josh Powell, 36, when he carried out the murder/suicide on Feb. 5, 2012.
Moments after the two boys arrived for a supervised visit at Josh Powell's rented home, the father started a fire that killed the boys and also claimed his life.