Seventy-nine harried hours of construction, congestion and the closure of the main San Francisco approach to the Golden Gate Bridge — May 28 to June 1 — will produce, at long last, the Presidio Parkway.

Decades of longing, 15 years of planning and seven years of construction are beginning to wrap up. Crews are putting the finishing touches on the 1.6-mile parkway, and the lights and safety systems in the tunnels are being tested. If everything goes according to plan, the new bridge approach — officially still known as Doyle Drive — will be complete.

There’s still about a year of landscaping, trail building and work on streets within the Presidio to do. But commuters, after two years of sharing a temporary roadway, will travel on the finished product. It includes two sets of tunnels, a pair of high viaducts, two low viaducts and a new off-ramp into the Presidio. There are also new connections between highways 1 and 101.

“This project has been so visible,” said Molly Graham, a spokeswoman for the project. “People drive it every day and see the progress. But it will be a whole new driving experience.”

Drivers warned away

Before that can happen, however, drivers who rely on the Golden Gate Bridge will face three days of doing without — or getting stuck in what promises to be horrendous traffic.

To allow construction crews to demolish parts of the current roadway and build connections to the new bridges and tunnels, Highway 101 will be closed from 10 p.m. May 28 until 5 a.m. June 1. Closures will begin at Lombard and Divisadero streets and extend to Highway 1.

The bridge will remain open, along with Highway 1, and left turns will be allowed from Park Presidio Boulevard to California Street and Geary Boulevard, the two main detours. Police and parking control officers will help direct traffic.

Nonetheless, transportation officials fear gridlock, especially on May 29, a Friday. They’re advising commuters to work from home, take ferries if they can squeeze aboard or be prepared to sit in slow-moving traffic.

“Our message that weekend is definitely stay away,” Graham said.

Carefully scripted schedule

While Doyle Drive is closed, crews will be busy. Peter van der Waart van Gulik, chief executive officer for Golden Link Concessionaire, the firm responsible for the second phase of the project, said workers will follow a carefully scripted schedule that leaves little room for delays.

Once traffic stops flowing, demolition crews will rip up the sections of roadway now in use that stand in the way of the future parkway. Then they’ll begin the longest part of the job, grading, laying down steel rebar and pouring a type of long-lasting concrete that needs time to cure. The concrete work, which will take place in three locations, is expected to take 62 hours, van der Waart van Gulik said.

“We will need to be working around the clock those 79 hours,” he said. “It’s a massive operation.”

The new ride through the parkway will take drivers in each direction across the viaducts and through the tunnels, offering views of the Golden Gate Bridge for northbound drivers and the Palace of Fine Arts and the downtown skyline in the other direction.

All connections between highways 101 and 1 will be reopened — the northbound 101 to southbound 1 off-ramp has been closed since 2010. A new off-ramp will take drivers to the Marina or, for the first time, into the Presidio.

“In the past, it was a military base, so access was restricted,” Graham said. “Now that it’s a national park, access is encouraged.”

It’s been a long road to replacing the main route to and from the Golden Gate Bridge. In 1933, the road was built with no shoulders, no median and narrow lanes. In 1945, the Golden Gate Bridge District turned it over to the state Division of Highways, predecessor to Caltrans.

Obstacles overcome

Ten years later, the bridge district asked the state to rebuild Doyle Drive and make it wider. When the state came up with a plan for an eight-lane highway with a median, San Franciscans objected, and the state Legislature passed a bill requiring San Francisco’s approval to widen the highway. Numerous attempts to replace Doyle Drive without widening it repeatedly fell victim to community opposition and lack of funding.

Money eventually came from a variety of sources, including San Francisco sales taxes, state transportation funds and federal stimulus dollars.

The Presidio Parkway, which cost about $1.1 billion, emerged from about 15 years of planning, studies and negotiations. The design was chosen in 2006 after planners, engineers and community groups winnowed down 16 options.

Construction of the new approach started in late 2009. The narrow, seismically unstable original roadway — which rated a 2 out of 100 on the Federal Highway Administration’s structural safety index — was demolished in 2012. Traffic was moved onto the temporary alignment now in use that shares a single tunnel and high viaduct while the second half of the project was constructed. The first phase involved building a new tunnel, high viaduct and temporary roadway and demolishing most of the old Doyle Drive.

The final traffic shift had been expected to take place late in the year, but the dry winter allowed construction to move more quickly than anticipated, Graham said.

Even though the new roadways are scheduled to open June 1, a significant amount of work remains. Over the next year, Golden Link will cover the tunnels in dirt and extend Halleck Road from the Presidio across the eastern set of tunnels near the main base to Old Mason Street. Crews will also extend Crissy Field Marsh beneath the low viaducts and build trails atop the tunnels and beneath the viaduct.

Project’s end in sight

Sometime in the middle of 2016, the project will officially be completed. The Presidio Trust will do more extensive landscaping, and Golden Link will move from building to operating and maintaining.

Under an unusual private-public partnership agreement, Caltrans’ first, Golden Link signed on to build the second phase of the project and then operate and maintain the parkway for the next 30 years, filling potholes, replacing light bulbs and towing away stalled vehicles.

Under the agreement, Caltrans will pay the consortium $488 million: $175 million when construction is completed and the rest spread out in payments over the next three decades.

Michael Cabanatuan is a San Francisco Chronicle staff writer. E-mail: mcabanatuan@sfchronicle.com Twitter: @ctuan