st. louis • The Gateway Arch was topped in high drama on a sparkling fall day in 1965. The sweeping landscape around it took shape over many years, its progress measured in sod squares and tree plantings.

The idea was for a pastoral place amidst downtown bustle that would complement, not clutter, the glistening form rising above trees, lawns and ponds. There were quibbles over details, but today's 91-acre riverfront park is essentially what architect Eero Saarinen and landscaper Dan Kiley had in mind.

Their original, winning design in 1948 was much busier — a major irony, considering the competition under way to enliven the Jefferson National Expansion Memorial and greatly improve its connections to downtown. The original design included a frontier village, above-ground museums and cafes.

Those ideas fell away over the next two decades, first during the protracted battle to remove the old riverfront railroad trestle and later because of diminished federal appropriations. But the modified design approved in 1964 is apparent to anyone who strolls the park.

"Saarinen and Kiley worked very closely together," said Regina Bellavia, author of an official 1996 history of the landscape project. "Kiley wanted tulip poplars, not ash trees. He wanted it more forested. But the alignments are his. They bring your eye to the Arch, and that was the idea. I believe Kiley was satisfied with what was achieved."

Saarinen died in 1961, one year before work began on the Arch he designed. Kiley left the project in 1964, but the National Park Service continued using his plan. Kiley died in 2004 at age 91.

Peter Morrow Meyer, a landscape architect in Bristol, Vt., who worked with Kiley two decades ago, said Kiley spoke often of the Arch project — his time with Saarinen, his frustration over the trees and his overall pride in the work.

"He loved working with Eero, and he told tales of no sleep and lots of gin," Meyer said. "Overall, the (Arch) grounds were pretty true to what he designed. He was proud of it. He wanted the broad sweep and the purity of it. For him, anything else was just decoration.

"But the trees — that ate at him," Meyer said. "Any time the Arch came up, the first thing he say was, 'Those were the wrong trees.'"

Another irony today is that Kiley's frustration over the choice of trees is back with a vengeance, with or without any remaking of the grounds. Almost half of the park's 2,069 trees are Rosehill (white) Ash, a tree species threatened by the emerald ash borer, a pest that reached the U.S. on a Chinese lumber shipment. The ash-killing borer has been found in isolated places in Illinois and Missouri.

Bob Moore, of the National Park Service staff at the Arch, said a study team is reviewing replacement species, including Kiley's beloved tulip poplars. The ash trees line the walkways on the grounds. Other species, including cypress, red buds and river birch, were planted around the two ponds and other places in the park.

"We know we're eventually going to have to replace the ash," Moore said. "We have decided to replace them with one species, because that is one of the defining characteristics of the landscape."

Moore said he toured the grounds with Kiley in the early 1990s. Tree choices aside, Moore quoted Kiley as saying of the grounds, "'This is what I had in mind.'"

Bellavia, author of the official history, worked on the Arch staff during the mid-1990s and completed her "Cultural Landscape Report" in 1996. She served as a consultant last summer on the ash-tree issue, and is a facilities manager at Boston College.

The basic idea of the competition is to create more attractions on the grounds, improve pedestrian connections to downtown and extend the park to the East St. Louis riverbank. The National Park Service and CityArchRiver2015, a local foundation pressing for a busier riverfront, are sponsoring the competition.

An eight-person jury — the system used in 1948 to choose Saarinen's Arch — is to pick a winner on Sept. 24. Forty-nine teams entered the process in January.

WAYS OVER ROADS

Area leaders have grumbled for years about the problem of getting visitors across Memorial Drive and the depressed lanes of Interstate 70 to the Arch grounds.

Saarinen and Kiley proposed elevated walkways linking the Arch grounds to Luther Ely Smith Park in front of the Old Courthouse, but they never were built.

All five teams in the current competition propose ways over those busy roads. They also envision additional uses for the riverfront park, from amphitheaters to bicycle rentals.

All of that harkens to the original call for the park in the 1940s. Saarinen's winning design included a frontier village, an outdoor campfire theater, two above-ground museums and two restaurants on the north and south overlook areas.

Then came the protracted battle with the Terminal Railroad Association, which owned the dingy trestle running from the downtown yards and along the riverfront into the city's north side. The National Park Service wouldn't begin work without moving the trestle. Not until 1957 did Saarinen come up with the model of tunnels and cuts for the tracks that exists today.

By then, Saarinen and Kiley had stripped away the frontier village and above-ground museums, preferring an underground museum and a more pastoral grounds. Saarinen called it a "more mature and classic design."

Groundbreaking was in 1959. Saarinen died after surgery for a brain tumor on Sept. 1, 1961, at age 51. The first concrete for the Arch foundation was poured in 1962, and the final piece of the Arch was fitted on Oct. 28, 1965. The first rides up the Arch tram took place almost two years later.

Embarrassment over the muddy, unfinished landscape finally led to a push to complete it in 1970, when park officials chose ash over tulip poplars at the urging of local tree nurseries. Planting and sod-laying began the next year and continued through the decade. The ponds weren't finished until 1979.

Not until 2003 was the original idea of a grand staircase down to the river realized in concrete. That was done by connecting the two narrow staircases that were built in a budget compromise.

"Without the pedestrian overpasses at Memorial (Drive,) you can argue that it's still not finished," Bellavia said. "For me, the park is a way to enjoy nature in the middle of a city. That was the idea."