Military rescue crews have met to identify new areas to check and places to cover again with hundreds of people still considered missing.
"They've kind of transitioned from that initial response to going into more of a grid search," Colorado National Guard Lt. Skye Robinson said.
The state's latest count has dropped to about 580 people missing, and the number continues to decrease as the stranded get in touch with families.
One of the missing is Gerald Boland, a retired math teacher and basketball coach who lives in the damaged town of Lyons. Boland's neighbors, all of whom defied a mandatory evacuation order to stay behind, said Boland took his wife to safety Thursday then tried to return home.
Two search teams went looking for him Monday.
"He was very sensible. I find it amazing that he would do something that would put himself in harm's way," said neighbor Mike Lennard. "But you just never know under these circumstances."
State officials reported eight flood-related deaths, and the number was expected to increase. It could take weeks or even months to search through flooded areas looking for people who died.
With the airlifts tapering, state and local transportation officials are tallying the washed-out roads, collapsed bridges and twisted railroad lines. The rebuilding effort will cost hundreds of millions of dollars and take months, if not years.
Initial assessments have begun trickling in, but many areas remain inaccessible and the continuing emergency prevents a thorough understanding of the devastation's scope.
"The numbers are going to change tomorrow as we get into more places, and the numbers are going to change the day after that," Federal Emergency Management Agency spokesman Ricardo Zuniga said.
Northern Colorado's broad agricultural expanses are especially affected, with more than 400 lane-miles of state highway and more than 30 bridges destroyed or impassable.
A Colorado Department of Transportation helicopter crew has been surveying damage, said department spokesman Ashley Mohr.
County officials have started their own damage tallies: 654 miles of roads in Weld County bordering Wyoming, 150 miles of roads in the Boulder County roads foothills, along with hundreds of bridges, culverts and canals.
Hard-hit Larimer County hasn't begun its assessment, with approximately 600 people there still awaiting rescue, but officials said the widespread damage leaves little doubt about what the price tag will be.
"It's going to be astronomical, there's no way around it," Capt. Ralph Kettle with the Poudre Fire Authority in Ft. Collins.
Dale Miller, road and bridge director for Larimer County, said it could compare to the damage wrought by a 1976 flood that killed 144 people. It took two years to rebuild after that disaster.
State officials have put initial estimates at more than 19,000 homes damaged or destroyed throughout the flooded areas.
Federal aid is forthcoming — it's not known how much yet — after President Barack Obama's disaster declaration. An initial $5 million has been pledged.