Cracks appear

Cracks appear

Credit: Kelly M. Grow/ California Department of Water Resources via Getty Images

On Feb. 7, a small hole appeared in the Oroville spillway, which is meant to provide overflow relief for the Oroville Dam in Northern California.

First hole

First hole

Credit: Kelly M. Grow/ California Department of Water Resources via Getty Images

The hole, shown here on Feb. 7 triggered an evacuation of nearly 200,000 people. Ultimately, however, with more rains coming, water-department officials decided they needed to use the damaged spillway to continue lowering the water levels in Lake Oroville, so that water didn't overtop the dam and cause truly catastrophic devastation.

Rushing waters

Rushing waters

Credit: Kelly M. Grow/ California Department of Water Resources via Getty Images

On Feb. 9, the Lake Oroville spillway flows late Thursday afternoon as 35,000 cubic feet per second (cfs) of water was released over the damaged spillway February 9, 2017 in Oroville, California.

No choices

No choices

Credit: Florence Low/ California Department of Water Resources/Getty Images

Water flows down the Oroville Dam main spillway at 55,000 cubic feet per second (cfs) February 11, 2017 in Oroville, California.

Huge erosion

Huge erosion

Credit: Elijah Nouvelage/Getty Images

The scale of the damage and erosion at the Oroville Spillway can already be seen on Feb. 13.

Scale of erosion

Scale of erosion

Credit: Elijah Nouvelage/Getty Images

On Feb. 13, water flowed down the Oroville Spillway. The huge area covered by the water's outlet gives a hint of the scale of erosion below.

Pounding waterfall

Pounding waterfall

Credit: Elijah Nouvelage/Getty Images

On Feb. 14, sprays from the pounding waterfall cascading over the Oroville Spillway created a rainbow. The pounding whitewater was causing extensive damage to the spillway and mountainside beneath it.

Extensive damage

Extensive damage

Credit: Dale Kolke /CA Dept. of Water Resources/Reuters/Newscom

An aerial view of the damaged Oroville Dam spillway site with a huge debris field in the diversion pool area just below the spillway on February 27, 2017 in Oroville, California.

Swept away

Swept away

Credit: Rich Pedroncelli/AP

A small flow of water goes down Oroville Dam's crippled spillway Tuesday, Feb. 28, 2017, in Oroville, California.

Dramatic difference

Dramatic difference

Credit: Expedition 50 crew/NASA/JSC

The erosion in the Oroville Spillway can be seen from space on Feb. 22 in this image taken by a member of the Expedition 50 crew on the International Space Station. The outlet flow appears markedly wider halfway down the spillway.

oroville-massive-erosion

oroville-massive-erosion

Credit: Dale Kolke / California Department of Water Resources

The massive amount of erosion can be seen from above in the diversion pool just below the spillway in this photo taken Feb. 27.

erosion-field-oroville-spillway

erosion-field-oroville-spillway

Credit: Dale Kolke / California Department of Water Resources

Another aerial view of the large debris field in the pool immediately below the Oroville Spillway, taken on Feb. 27. The spillway sustained massive damage after heavy rains pounded the region in February.