A neglected 1920s-era, brick-and-timber warehouse near Sports Authority Field at Mile High will gain new life as part of a redevelopment project promising to bring office, retail and residential to the tired industrial stretch.

Steam on the Platte, a joint effort by Denver’s Urban Ventures and White Construction Group of Castle Rock, will reinvent 3.2 acres along the South Platte River at West 14th Avenue and Zuni Street as a creative, vibrant area that developers hope will help provide ammunition for a long-awaited revitalization of the entire Sun Valley neighborhood.

“It’s a little gem. It’s a little rough right now, but it won’t be for long,” Urban Ventures president Susan Powers said.

The heart of the $50 million project is the 65,000-square-foot warehouse, which was best known, until recently, for being the big white building whose windows displayed photos of children — a giant public-service announcement, visible from Interstate 25, for lead-poisoning awareness.

The white paint now stripped away, the three-story building will be renovated into a creative office space that opens in the third quarter of 2016. NIMBL, a technology consulting firm based in Denver, has committed to being the anchor tenant.

Another building, with an arched roof and right along the river, also will be saved and transformed into a restaurant by late 2016 or early 2017. More office space and residential units will be built in future phases.

“It’s a neighborhood that’s been overlooked for so many years,” Powers said. “There’s a light-rail station, there’s a station area plan that’s very exciting, and there’s a lot of planning going on by the city and stadium district and housing authority. The time is right for this to take off now.”

The Denver Office of Economic Development is championing the project as a catalyst for the redevelopment of Sun Valley and the South Platte, both of which are priorities for Mayor Michael Hancock.

“The idea of new life in this industrial corridor is transformational, both culturally and economically,” executive director Paul Washington said in a statement.

White Construction president Timothy White said he hopes that Steam on the Platte becomes the front door to the neighborhood.

“It’s got great potential to set the stage for what that whole area to the west and the southwest is going to look like,” White said.

White Construction has considerable experience working on adaptive reuse projects, as well, including The Source, a foundry-turned-culinary center on Brighton Boulevard, and The Stanley Marketplace now under development in Aurora.

Steam’s 1928 warehouse has experienced its share of wear and tear over the years but remains “a beautiful masonry-heavy timber building with great interior amenities,” White said.

The site has been home to the Johnson and Bremer Soap Factory, a rag baler and a ceremonial bathhouse, according to developers.

“I love the corridor it’s in,” White said. “You get up on the roof and it’s a great east-west view. It’s right off the interstate. And the other great thing: It’s buffered on the south side by the light rail and on the west side by the Platte River.”

“There are very few properties that you can develop that are right on the river,” Powers said.

Emilie Rusch: 303-954-2457, erusch@denverpost.com or twitter.com/emilierusch