(AP) — An expert panel says the U.S. Army Corps of Engineers wasn’t to blame for record Missouri River flooding this year. But the panel said several changes, including improved monitoring of pending snowmelt, could help avoid a disastrous repeat.

A 99-page report released Tuesday says that the current manuals and procedures could be improved and updated.

The corps has said that the floods caused $630 million in damage to the levees, dams and channels built to control the river.

The analysis said “climatic extremes” appear to be getting “bigger and more frequent,” with the experts calling for updated flood probability models and procedures.  It did not cite climate change as a factor, saying the issue was “beyond the scope of this report.”

The report said the 2011 flood was the “the largest of the period of record in terms of runoff volume, and it stressed the mainstream reservoir system and its operators as never before.  Many people were dismayed that such a damaging event could occur, in spite of the flood control reservoir system.”

An expert from the panel said May rainfall in Montana exceeded 300 percent of normal, surprising everyone and causing the biggest problems.  But he said such unusual weather may be a more common part of the weather cycle, no matter the cause.

“Back when they designed this master manual, it was a weather event that they probably just didn’t think was possible,” said Bill Lawrence, a hydrologist with the National Weather Service in Tulsa, Okla.   “I think whether or not you believe in climate change is beside the point.”

The experts waded cautiously into the debate over whether the corps should release more water from upstream reservoirs in order to leave more room for floodwater storage. This past season, the corps was forced to release water from the full reservoirs knowing it would cause downstream flooding.

“The unprecedented inflow volume tested the reservoir system more than ever before,” the report said. “The panel recommends a review of the system storage allocations, to include the flood-control storage needed for floods like 2011 or larger.”