Can the Mitchell Park Domes Be Saved?

National Trust for Historic Preservation names them a ‘National Treasure,’ releases engineering report aimed at preservation of the Milwaukee landmark

The National Trust for Historic Preservation today named Milwaukee’s Mitchell Park Domes a “National Treasure,” calling the landmark “a unique engineering marvel, and a nationally significant example of midcentury modern architecture.” The Trust is also releasing a new engineering report that “demonstrates a more comprehensive and cost-effective path forward for preserving the Domes—a potential solution that could ensure that these one-of-a-kind buildings remain a part of the Milwaukee community into the future.”

Officially called the Mitchell Park Horticultural Conservatory, but popularly known simply as “The Domes,” the glass houses have been a center of community life and an international tourism destination for more than 50 years. In 1958, Milwaukee architect Donald L. Grieb won a national competition with his design for the Domes, which were constructed between 1959 and 1967. Their distinctive architecture features the world’s first “conoidal” – or cone-shaped – domes, which the Milwaukee Journal Sentinel has called “adventurous structures that remain unique in the world.” The Cultural Landscape Foundation, based in Washington, D.C., named the Domes an “at-risk cultural landscape” and compares their significance to St. Louis’s Gateway Arch, another “Modernist marvel.

Generations of Milwaukeeans and thousands of tourists visit the Domes annually. Attendance was 240,000 in 2015. Several hundred residents turned out for a public hearing about the Domes’ future in February 2016, after they were temporarily closed following the discovery of a small shard of concrete in one dome. Citizens overwhelmingly urged county officials to preserve them. Arthur Capps, 12, said the Domes are “as important as the Milwaukee Zoo. It’s like a zoo except for plants,” such as the exotic “sausage fruit tree or the golden shrimp tree.”

“Anyone who has visited the Milwaukee Domes can appreciate what a stunning and absolutely one-of-a-kind place they are,” said Stephanie Meeks, president and CEO of the National Trust for Historic Preservation. “From our work at other icons of modern architecture, like Houston’s Astrodome or Philip Johnson’s Glass House, we also know that inspiring, innovative architecture often requires equally creative solutions. Rather than risk losing this iconic piece of Milwaukee’s heritage, we need a thoughtful, long-term preservation solution for the challenges facing the Domes.”

Despite the Domes’ significance and continued role in the community, the Domes remain threatened. Milwaukee County, which owns the complex, is considering demolition of one or more of the Domes, along with other options ranging from partial restoration to full reconstruction of the buildings. This situation also landed the Domes on the National Trust’s 2016 list of “America’s 11 Most Endangered Historic Places.” There has since been “a lot of response about the Domes” on the Trust’s website, including people signing a petition to save them, according to Jennifer Sandy, senior field officer for the Trust’s Chicago office. Reached by phone, Sandy said that support is by both those familiar with Domes and people “fascinated by their architecture” who now want to visit them. Sandy complimented county officials and the Domes task force for “engaging in a responsible process” to consider options for the Domes, including as part of Mitchell Park and the surrounding neighborhood.

The Trust, a privately funded nonprofit organization, mobilizes its more than 60 years of expertise and resources to protect a growing portfolio of National Treasures that are threatened buildings, neighborhoods, communities, and landscapes that stand at risk across the country. The Trust’s National Treasures program “demonstrates the value of preservation by taking direct action to protect these places and promote their history and significance.” That may include “raising needed funds, building coalitions to prevent demolition” and other efforts to ensure that “the icons of the past remain with us in the future.”

Photo courtesy of The Park People of Milwaukee County

To that end, the National Trust and Milwaukee Preservation Alliance, a volunteer-led nonprofit organization, are launching “a coordinated campaign to rally the public to support a preservation solution for the Domes.”

Also, a new report identifies a comprehensive rehabilitation approach for the Domes estimated at $18.6 million, around one-third the cost of the full rehabilitation options developed by GRAEF. The peer review of GRAEF’s repair proposals was prepared by Wiss, Janney, Elstner Associates (WJE), an engineering firm with decades of experience working on world-famous buildings including such high-profile projects as St. Louis’s Gateway Arch, the Metropolitan Museum of Art in New York, and the Washington Monument.

WJE’s report concludes: “Based on our observations and experience with similar structures, it is our opinion that the Domes can be preserved and restored.” It notes that they “have performed well during their first fifty-eight years of service and can be preserved. The condition of the precast concrete framing and glass cladding are repairable, and replacement of these systems is not necessary at this time.”

The new analysis continues, “Overall, the glass cladding and precast concrete have performed well considering that minimal maintenance and repairs have been completed on the domes. The primary issues are water leakage and spalling concrete at the embedded connections… Past repairs have not addressed water leakage into the domes.”

WJE staff visited the facility and also reviewed all GRAEF’s architectural and engineering reports and letters about the Domes since 1994. The peer review analyzed GRAEF’s five proposed restoration options and one replacement in-kind option, which were cost-estimated from $14 to $64 million.  

Though WJE’s proposed repair would cost $18.6 million, $4.6 million more than GRAEF’s Option 1, the cost would be far less than GRAEF’s other proposed options, or what county officials roughly estimated might cost up to $75 million.

The report explains,With properly designed and installed repairs and regular maintenance, it is our opinion that the precast framing and glass repairs described in GRAEF’s Option 1 will extend the useful life of the domes for many years. If water leakage is addressed and concrete repairs are completed, we would not expect concrete repairs would be needed for ten to fifteen years or more… With continued future maintenance related to water leakage, we anticipate that concrete repairs would be minimal in future once spalling at all embedded connections is addressed.”

aerial view of the Mitchell Park Domes
Photo courtesy of The Park People of Milwaukee County

“It’s hard to imagine Milwaukee without the Domes,” said Peter Zanghi, president of the Milwaukee Preservation Alliance, Inc. “For those who grew up in Wisconsin, the Domes are a landmark that contributes to Milwaukee’s unique identity. Rising gracefully from the southern edge of the Menomonee Valley, the Domes are not just beautiful, they are also useful – providing a valuable educational experience to the thousands of students who visit them every year, and functioning as a venue for everything from weddings to live music to model train shows. Milwaukee is fortunate to have the Domes, and MPA looks forward to finding a solution to preserve them for future generations.”

WJE’s full report will be presented at the Domes Task Force meeting on Wednesday at 5:30 p.m. in the lobby of the Domes, 524 S. Layton Boulevard in Milwaukee. Time permitting, the public may be allowed to speak.


 Virginia Small is a Milwaukee freelance writer who has written for publications throughout the United States.


About The National Trust for Historic Preservation

The National Trust for Historic Preservation, a privately funded nonprofit organization, works to save America’s historic places.

About National Treasures

The National Trust for Historic Preservation mobilizes its more than 60 years of expertise and resources to protect a growing portfolio of National Treasures that are threatened buildings, neighborhoods, communities, and landscapes that stand at risk across the country. The Trust’s National Treasures program demonstrates the value of preservation by taking direct action to protect these places and promote their history and significance.

About Milwaukee Preservation Alliance, Inc.

The Milwaukee Preservation Alliance is a nonprofit organization devoted to promoting stewardship and awareness of the historic, cultural, and economic value of Milwaukee’s built heritage. MPA aims to strengthen Milwaukee’s neighborhoods by advocating for and promoting unique cultural spaces and architectural assets to foster a strong and vibrant community, as well as demonstrating the link between historic preservation and viable economic development.

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