Across the nation, malls are being mothballed. After a heady period of expansion when malls seemed to spring up everywhere, the retail mindset has changed. With vacancy rates up in many large indoor retail centers, there’s been a shift toward mixed-use developments or outdoor malls designed to resemble the downtown shopping districts they replaced.

Here in the Lower Hudson Valley, where one of the first outdoor shopping centers opened more than 50 years ago, that trend is evident. Next week, the Shops at Nanuet, a new outdoor shopping center that replaces the moribund Nanuet Mall, is scheduled to open. It will join Westchester’s Ridge Hill in Yonkers and a proposed outdoor luxury mall in White Plains.

“Part of the challenge is to give people a reason to go to the mall,” said Maureen McAvey, a senior fellow for retail at the Urban Land Institute based in Washington. “And for generations X, Y and for the millennium, who are so used to constant stimulation, there is a need offer many options and constant change.”

The mall, she added, “is a part of the suburban fabric. Increasingly, we are seeing them become mini-downtowns in some areas with mixed uses (incorporating) offices and residential.”

After years of planning and construction, the shops at Nanuet in Clarkstown is ready for its commercial debut. Opening ceremonies are set for Oct. 10-13.

The nearly 800,000-square-foot open-air mall off Route 59 in Rockland County sports an open street-like format with amenities like green space and benches. There is a 24-Hour Fitness, a 12-screen Regal movie theater and a Fairway market. It was estimated to be a $150 million renovation project.

In 1969, it was called the Nanuet Mall and featured Bamberger’s, which morphed into Macy’s and a  Sears. Both stores remained open during construction and await neighbor stores, which will be connected by walkable streets, one called Fashion Drive, Storefront architecture varies; some are modern with large windows while others have turrets and arched doorways.

General Manager Ryan Hidalgo views the new center with an eye to its past. As a Rockland teenager, he worked part time at a Disney store here. Now married with children, he is employed full time to direct the more than 50 stores in this mall.

“I grew up here and feel very attached to this place. Rockland County has changed in terms of density, affluence and demographics,” he said during a tour as construction hit its final stages.  “It makes sense for the mall to change. This is a modern-day mall, coming at just the right time for the community.”

This new facility is intended to draw people from many communities to shop and spend time together.

“We know we are competing for people’s leisure time,” he added.

Good community planning looks to find new uses for old spaces, said Rob Lane, an architect from Dobbs Ferry. He is a senior fellow for community design at the Regional Plan Association, a group of researchers and regional planners that look at development and sustainability in the New York region.

“There are a whole set of building types that need to be rethought. We have to thing creatively about how to reuse these places,” he explained. “It is one thing to build an entirely new shopping center in an auto-centric location, then to take a dying mall and reinvent it. Malls of today have to consider how their employees will get to work and what will keep customers on-site for long stretches of time.”

He said these new malls that connect to public transportation, such as local bus services, offer new opportunities for job seekers and shoppers, advantages that should not be overlooked.

More than just adding retailers, the new centers expand service choices that had traditionally been found at malls.

That is the case with Westchester’s Ridge Hill shopping center in Yonkers, which opened in fall of 2011. It has an adjacent luxury housing component and office space to coordinate with the theaters, health club, restaurants and a Legoland Discovery Center. The stores in the roughly 750,000 square-feet of retail space are considered high-end retailers and include Orvis and L.L. Bean, which have not had storefronts in this area.

One of the reasons we picked Pidge Hill was that it was an open-air site on over 80 acres. It allowed us to created something that city of Yonkers and the county of Westchester wanted, which was a downtown experience,” said Kathy Welch, executive vice president for retail development at Forest City Ratner, the project developer.

She said each store was designed to have an individual look. It is also walkable with a main avenue called Market Street. In response to concerns about being open air during unpleasant seasonal weather, she said customers don’t seem to mind, except in rare extreme cases.

The center, she added, also has a farmer’s market on Fridays with fresh produce, as well as community events like a bike day and Harvest Festival on Oct. 26. There is WestMed Medical Group, where about 1,000 or more patients are seen a day, Welch added.

“This becomes a great place for families, not just somewhere to run and pick u your goods and leave,” she added.

In 2011, the Cross County Shopping Center off the Cross County Parkway in Yonkers completed a $105 million renovation. The center, one of the nation’s forst shopping malls when it opened 50 years ago, remains a sprawling open-air destination, with stores, restaurant and entertainment options accessed by a series of landscaped pathways.

On the horizon is another high-end shopping center on Bloomingdale Road in White Plains called Heritage White Plains, planned by Faros Properties and Caspi Development. Along with two four-storey office buildings, the plan calls for streetfront retail space for up to 18 boutiques. It is expected to open in 2016.

The right concept is the one that makes sense for the particular community, says Tom Schneider, executive vice president of Simon Properties Group, which developed the shops at Nanuet and operates the Jefferson Valley Mall in Yorktown and the Westchester.

“It really comes down to what you can build on the site,” he said.”You’d like to be as many things to as many people as possible.”