At noon Monday, Oregon County Southern Commissioner John Wrenfrow said he went to his worst areas before daylight trying to assess the damage.
On Sunday, most roads still were holding.
Until the water goes down, he said, it will be difficult to assess the road damage. Many roads were closed because of washed-out areas and high water at low-water crossings and bridges.
The rain also took its toll on paved state highways. Highway 160, west of Alton at the Barren Fork Bridge, Hurricane Creek, Highway 142 near Billmore, Route A near Couch were all closed Monday, making travel extremely difficult around the county as rain continued to fall.
Most areas received about 3 inches of rain Saturday, four inches on Sunday and another five inches on Monday. Earlier in the week, the area received about two inches.
Thayer Mayor Earl "Buddy" Rogers said city storm drains were able to handle the water.
The only problem in the city was at the wastewater treatment plant, where a valve was not properly opened.
It was human error, Rogers said. City workers were able to correct the problem, he said.
Fun and Friends Senior Center in Thayer was closed all day Monday as volunteers mopped up water after a sump pump failed to work.
In neighboring Mammoth Spring, Mayor Jean Pace said the city did not experience any serious flooding, mostly because the rain came down steadily over several days, rather than all at once.
"I've been watching the river all day," Pace said.
Pace said the city has only had one serious flood in recent years, which happened on the week of city-wide cleanup when 11 inches of rain fell in a short period of time.
"People's debris was floating down Main Street," Pace said.
Pace said the most cost associated with recent storms has been at the wastewater treatment plant, as component parts have had to be replaced three times in the last six weeks.
"There is nothing we can do about it," she said, adding that the city has installed lightning rods, yet continues to sustain damage.
The heavy rain over the weekend had one positive effect, Missouri Department of Transportation bridge inspector Ron King said.
High water under the Frederick Creek Bridge under construction on Route Y caused some bends in the creek bank to straighten out, King said.
The project is scheduled to be complete by the end of May. "It may be sooner than that," King said.
Also on Monday, Alton Schools cancelled classes as rural road were impassable for buses.
Gov. Jay Nixon activated the Missouri National Guard to help with response efforts in parts of state impacted by flooding and threats to levees, particularly in the Poplar Bluff community where many areas were evacuated.
Parts of West Plains also were evacuated.
The weather forecasts for this week call for continued heavy rain. "We just have to hope for the best," Mayor Rogers said.