In April, President Trump ordered a review of 27 national monuments around the country. The interior secretary made his recommendations last week.
Zinke said unspecified boundary adjustments for some monuments will be included in the recommendations he planned to give President Donald Trump.
"This is great news for Colorado and I’m thrilled the Department of the Interior listened to Coloradans," Sen. Cory Gardner Said.
“We believe any review of Canyons should conclude that no changes to the designation are necessary,” said Republicans Sen. Cory Gardner and Rep. Scott Tipton in a letter.