The Utes (17-8, 8-5) ran away with the game in the first half despite trailing by eight early.
Utah took a 44-28 lead into halftime thanks to a 20-0 run. Lorenzo Bonam hit a pair of 3-pointers during the stretch as the Huskies went more than nine minutes without a field goal.
The Utes shot 58.1 percent in the first half.
It was more of the same in the second half as an 11-0 run stretched the Utah lead to 55-34 and Washington (9-16, 2-11) never made a significant run.
Utah's Kyle Kuzma had his 15th double-double of the season with 13 points and 10 rebounds. Van Dyke's 16 points were a career high.
David Crisp paced Washington with a career-high 31 points and Noah Dickerson added 18.
Utah out-rebounded Washington 39-23.
Washington: The Huskies were without Markelle Fultz and his 23.2 points per game due to a sore right knee. Saturday was the second consecutive game he was out and the Washington offense clearly missed him. The Huskies have now lost seven straight.
Utah: The Utes won their second consecutive game as they try to keep their NCAA Tournament hopes alive. The win, however doesn't carry much weight considering Washington has just two conference wins and was without Fultz.
Washington: The Huskies host Arizona State on Thursday.
Utah: The Utes travel to face Oregon on Thursday.