PALM BEACH GARDENS, FLA. -- A missing link on the 1,857-mile Interstate 95 highway that hugs the nation's Eastern Seaboard has opened, and planners predict an explosion of growth in south Florida rivaling suburban Los Angeles.

The 30-mile section of I-95 in south Florida, slicing through Martin and Palm Beach counties about 75 miles north of Miami, will offer a route for growth opportunities long thwarted by construction and environmental concerns.

Don Vogel, director of the Palm Beach Gardens Planning, says opening the road may forever change the landscape of largely undeveloped Martin and St. Lucie counties, coastal communities north of West Palm Beach.

"I think we're seeing in south Florida what Orange County, Calif., went through 10 to 15 years ago," Vogel said. "We're just on the verge of exploding."

Opening the missing interstate link makes it possible for I-95 drivers to speed from Houlton, Maine, on the U.S.-Canadian border, to Miami on the $6 billion highway.

Only a short section, less than a mile, north of Philadelphia near the Pennsylvania Turnpike remains unopened, said Larry Green, a Federal Highway Administration engineer in Washington.

Completion of the 30-mile link is expected to rob the aging Florida Turnpike of $14.2 million in annual toll revenue and hundreds of thousands of weary Yankees making their southbound escape from snow and ice to palm trees, sand and surf.

Howard Hills, a Florida Turnpike regional manager, said I-95's new link could cut traffic on the 290-mile turnpike, running from Miami to Wildwood, in half.

"Truckers, commuters and people coming down on vacation already on it will stay on it," Hills said. "Our traffic will be greatly reduced during the next few months, but it will balance out toward the end of 1988."

Many developers, anticipating the completion of the missing link and eager to begin building, have already submitted plans for numerous industrial and commercial projects.

Already planned near the congested main artery is Florida's largest shopping mall -- a 1.6 million-square-foot project developed by Forbes-Cohen of Southfield, Mich. High-rise office buildings, restaurants, marinas and residential suburbs also are on the drawing board, Vogel said.

"When you put it all together, it's starting to look a lot like Miami," Vogel said.

Travelers heading north of Miami on the busy corridor now have six additional exits from north Palm Beach County to Stuart in Martin County, giving them relief from bumper-to-bumper traffic along scenic Rte. A1A, crowded U.S. 1 and the turnpike tolls.

The state spent $220 million on the 30-mile stretch, compared with $1 billion for the 383 miles of I-95 in the state, said Florida Department of Transportation spokesman Steve Liner. Construction began near Jacksonville in 1955.

Protests from environmentalists, upset the highway would cut through Jonathan Dickinson State Park and the Loxahatchee River basin, delayed work on I95's missing link for several years.

The original plan also would have cut through Jupiter Farms, where actor Burt Reynolds' father owned a horse farm.

After several years of wrangling in the early 1970s, FHA Administrator Norbert Tiemann canceled approvals for the route on the day former President Gerald R. Ford left office. The action sent federal highway officials scurrying back to redesign the road.

Tequesta resident Nick Nixon said influential citizens, including former assistant interior secretary Nat Reed, living on exclusive Jupiter Island, also opposed the original plans.

"I wanted to keep the road as far away from Hobe Sound as possible, and I make no bones about it," Reed said. Hobe Sound, an unincorporated area of 2,000 people, is located north of Jupiter and is popular with golfers.

Now that the road has opened, the $2-billion John D. and Catherine T. MacArthur Foundation, which owns about 16,000 acres along the highway, is expected to be instrumental in deciding the fate of the area.