The new Frederick Douglass Memorial Bridge over the Anacostia River is midway to completion and on track for a 2021 opening, according to the District Department of Transportation.

The project will replace the 70-year-old busy crossing that connects D.C. neighborhoods east of the Anacostia River to the seat of the federal government.

DDOT says the South Capitol Street bridge will feature three above-deck arches, two piers that will appear to float in the river and four pedestrian overlooks. Crews are nearly done with the bridge foundation and its arches will begin to rise as early as this fall, project officials said.

The rainy conditions of the past year — Washington’s wettest — hasn’t stopped the more than 150 workers on the site from laying piles and pouring concrete on the city’s largest infrastructure project in history, valued at $480 million.

“We’re really excited about the progress that we’ve made,” DDOT Deputy Director Everett Lott said Friday during a tour of the construction on the west side of the river. “You will be seeing more progress as the weeks and days go on. It’s going to be a great benefit to the residents of D.C.”

The new, wider bridge is being built parallel to the old one, near Nationals Park. Most of the construction is over the river, limiting the impact on traffic on the existing bridge. As the work advances, travel patterns will shift and lane closures will be needed on nearby roadways, including busy Interstate 295, which itself will undergo major improvements.

The bridge will be a much needed upgrade to the old crossing, which carries about 70,000 vehicles daily and has been deemed structurally deficient for years. A distinct structure with parallel arches, the bridge was designed to improve pedestrian and vehicular travel; a multiuse path will facilitate more crossings on foot and bike and green areas on each side of the bridge will provide space for community activities.

City and community leaders say they hope project, combined with major construction planned on the old campus of St. Elizabeths Hospital on the east side of the river, will help spur economic development in Ward 8.

“What we don’t have in Ward 8 is the kind of commerce and the kind of restaurants and amenities for which this side of the Anacostia is known,” D.C. Del. Eleanor Holmes Norton (D) said Friday while touring the bridge construction on the west side, near Nats Park, an area that has experienced significant redevelopment since the baseball stadium opened a decade ago.

“We think this bridge will help spur that” on the east side, Norton said.

And there are already signs of redevelopment on the St. Elizabeths campus, she said. The federal government plans to consolidate the Department of Homeland Security headquarters at the site and the District has been discussing building a new hospital at St. Elizabeths. A 1.3 million-square-foot complex for the U.S. Coast Guard headquarters was completed on the historic campus in 2013. The Washington Wizards in September opened a $69 million training facility on the St. Elizabeths campus, another project touted as a catalyst for development near the Congress Heights Metro station.

The bridge project is also viewed as a major step toward the transformation of the shores of the Anacostia. A modern bridge, officials say, will be more in line with the growing development in the area, which has transformed from industrial and military uses into thriving mixed-use communities and employment centers. Growth has peaked around Nationals Park and Navy Yard at the foot of the bridge.

Work is on finishing up on the support for the bridge and utility relocation on each side of the bridge where the city will build traffic roundabouts that will serve to slow down motorists. Once the new bridge is completed and the two traffic ovals connect the new bridge, traffic will be directed to the new structure and the old bridge will be demolished.

The new bridge will have six general travel lanes, adding one more lane of general traffic to help address a choke point.

Norton, who helped secure the funding for the project in Congress over a six year-period, said seeing the bridge finally start to go up is gratifying.

“You want the slowest traffic in Washington, try coming to this bridge around 5 o’clock,” she said. “I am pleased that it is six lanes. That will make a big difference.”