By Madison Park

CNN

SAN FRANCISCO (CNN) -- It's been a brutal year so far for California's infrastructure.

Swinging from a five-year drought to massive rainfall has pummeled the state's structures and roads. Damage to the state highway system is estimated to exceed $1 billion, according to the California Department of Transportation's estimates.

Here's what lies in ruins: portions of Pacific Coast Highway buried under landslides, a disintegrated spillway and a cracked bridge.

Mud Creek landslide- Pacific Coast Highway

Repair cost: Unknown

A monster of a landslide buried a quarter-mile section of the scenic coastal highway in California's Big Sur region.

More than a million tons of rock and dirt fell Saturday onto the Pacific Coast Highway, the main artery running through Big Sur. The section is about 60 miles south of Monterey.

The Mud Creek landslide covered the road, also known as State Route 1, in a 35-40 feet deep layer of dirt for about 1,500 feet. There were no injuries as the highway had been closed at that spot -- almost continuously since January -- because of landslides caused by unusually heavy rainfall.

The latest slide is the largest by far, and authorities said they don't know when it can be cleared.

Caltrans listed at least 10 landslide sites in need of repair on State Route 1 in Monterey County with estimates reaching $55 million. This sum excludes the latest landslide.

Oroville Dam

Repair cost: more than $274 million

Under heavy rainfall, the primary spillway that handles the overflow at the Oroville Dam eroded and formed a hole almost the size of a football field.

As the damaged spillway along with the backup channel struggled to handle the influx of water earlier this year, authorities feared that Lake Oroville was on the verge of overflow, threatening communities downstream. About 188,000 residents of Butte, Sutter and Yuba counties were evacuated in February. They returned to their homes four days later.

The concrete primary spillway remains splintered as crews have begun repairs.

California is borrowing up to $500 million to pay for repairs. The state hasn't given an estimate for how much the project will cost, according to Capital Public Radio. In April, the Trump administration approved $274 million in federal funding for repairs.

Pfeiffer Canyon Bridge

Cost: estimated $26.5 million

The bridge cracked after heavy rains caused a landslide that damaged one of its main support columns.

After closing the bridge in February, crews demolished the structure to make room for a new steel plate girder bridge. The Pfeiffer Canyon Bridge connects drivers to Big Sur, and serves a popular tourist route on Pacific Coast Highway.

Caltrans estimates that the new bridge will be ready in September.

CNN's Jason Hanna and Samira Said contributed to this report.