Mario Gandelsonas, principal with Agrest and Gandelsonas Architects, presented his vision to turn the vacant and drab Walnut Street into an informational and cultural hub at the Greater Des Moines Partnership on Friday afternoon.

But it will take a radical change and intense planning to turn the current street — whose only retailer is Walgreens — into the likes of the Third Street Promenade in Santa Monica, Calif.

Gandelsonas is up for the challenge, however, pointing out that he has been visiting Des Moines regularly for 25 years and has witnessed the transformation of the East Village and Western Gateway.

In Gandelsonas’ plan, the new-and-improved Walnut Street will be filled with restaurants, outdoor cafes complete with heating and cooling agents, pop-up shops, wider sidewalks and a bike share program. It would also be open to cars again, something that hasn’t been the case for the last 30 years.

Gandelsonas said he eventually envisions an area to hold outdoor film screenings, the addition of an upscale grocery store, and more residential options.

The addition of new shops and restaurants isn’t the only thing that will be changed — the plan will also make the area more cohesive. He wants to better incorporate the downtown skywalk system, adding more entrances that are more clearly marked, and connect Walnut Street to 10th Street and Fourth Street, two areas that already have distinct character and retailers.

However, there is still much to be done. Construction won’t begin until at least 2013, while the focus this year will be on leasing out space, completing the funding strategy and continuing planning the concept design. And even after all of that there’s no guarantee Walnut Street will be exactly as Gandelsonas has planned.

“We don’t know how this will be implemented,” he said. “But no one knew when the East Village started how it would end up, and we all enjoyed watching it.”