Photos: Oroville Dam Spillway Used For First Time Since Rebuild

The nation's tallest dam is back in business! California officials opened the flood-control spillway Tuesday, April 2, for the first time since it was rebuilt after crumbling down during heavy rains two years ago.

Water flowed freely down the $1 billion structure and into the Feather River, as rainstorms and the melting snowpack are expected to swell the surrounding lake behind the dam as soon as Thursday, April 4."We're going from flood to drought and drought to flood with very little normal in between," said Kris Tjernell, deputy director of the water resources department.

The original spillway was built in the 1960s on the 770-foot-high dam, located 150 miles northeast of San Francisco. When harsh storms caused the spillway to crumble apart in 2017, "dam operators reduced the flow and allowed water to run down an emergency spillway — essentially a low area on the reservoir's rim — but the flow began eroding the earthen embankment that had never been used," reported AP. As a result, authorities had to quickly order an evacuation of nearly 200,000 people living in communities downstream.

The new spillway "was designed and constructed using 21st century engineering practices and under the oversight and guidance from state and federal regulators and independent experts," said Joel Ledesma, deputy director of the water resources department's State Water Project.

See photos of the newly constructed Oroville Dam Spillway being used for the first time below:

Tuesday April 2, 2019

Water flows down the Oroville Dam spillway in Oroville, California.

California officials opened the flood-control spillway at the nation's tallest dam for the first time since it was rebuilt after it crumbled during heavy rains two years ago.

Department of Water Resources Engineer John King, center, thrusts a snow survey tube into the snowpack while conducting the April 2019 snow survey at the Phillips Station near Echo Summit, California.

The survey found the snowpack at 106.5 inches deep with a snow water equivalent of 51 inches at this location at this time of year.

Water flows down the Oroville Dam spillway in Oroville, California for the first time since it was rebuilt after it crumbled during heavy rains two years ago.

Department of Water Resources Engineer John King, left, and Kris Tjernell measure the depth of the snow survey tube in the snowpack while conducting the April 2019 snow survey at the Phillips Station near Echo Summit, California.

Culvin May takes a photo of the water flowing down the Oroville Dam Spillway in Oroville, California.

May helped rebuild the spillway as a carpenter for Kiewit Construction Company that did the work on the project.

Zack Rodriquez runs up a hill across from the Oroville Dam Spillway before water began flowing down the repaired structure, in Oroville, California.

Water flows down the Oroville Dam spillway in Oroville, California on Tuesday, April 2, 2019.

Department of Water Resources Engineer John King measures the depth of the snow survey tube in the snowpack while conducting the April 2019 snow survey at the Phillips Station near Echo Summit, California.

Another shot of John King, center, as he prepares to measure the depth of the snowpack during the April 2019 snow survey at the Phillips Station near Echo Summit, California.

Andy Reising, center, of the Department of Water Resources, analyzes data obtained while conducting the April, 2019 snow survey at the Phillips Station near Echo Summit, California.

AP contributed to this post.