More than 50 years of creating honest client partnerships, like the City of Livonia.


In 1962, OHM Advisors began with a simple premise: to create extraordinary relationships with our clients.

Since our beginnings, we've understood that meeting the advisory needs of our clients starts with building their trust. For close to 60 years, our goal has been to create honest client partnerships for today's challenges that last well into the future. 

Lasting Foundations
The principals of OHM Advisors back in the 1960s.

Relationships, Not Clients

In 1962, engineering veteran John E. Hiltz joined Melvin “Ernie” Orchard to form John E. Hiltz & Associates in Detroit, Michigan, with 15 employees. Their vision was a firm built on extraordinary relationships with municipal clients, providing insightful engineering counsel, and delivering on a promise to Advance Communities.  

Over the years, OHM Advisors has purposefully grown and diversified.

Purposeful Growth

Over the years, John E. Hiltz & Associates became Orchard, Papke, Hiltz and McCliment, Inc., Orchard, Hiltz & McCliment, Inc., and then OHM Advisors; while continually growing and diversifying our team and offerings to become a full-service consulting firm.

Some of our growth has been through strategic mergers and acquisitions and some has been organic, but the driving force has always been to create an exceptional team of people committed to best serving our clients.

Trusted advisors, working with our clients in the field.

Trusted Advisors

Close to 60 years later—with a talented 500+ team in multiple states—we’re still living our mission of Advancing Communities through our work with municipalities, state and regional agencies, schools, corporations, developers and local entities. We’ve grown our extraordinary relationships to become our clients’ trusted advisors, and continue to nurture those partnerships to endure for tomorrow's challenges.

Historic Highlights

Click below to learn how we grew from one office to many with a click on these important years in our history.

1962: Beginnings in Detroit, Michigan

John E. Hiltz, an engineer with more than 30 years of municipal engineering experience, joins forces with Melvin "Ernie" Orchard of Orchard Engineering, and Frank Papke and Dick Toal of Salle Engineering to form John E. Hiltz & Associates, Inc. The company starts in Detroit with 15 employees and serves as the consulting engineer for the City of Livonia, the beginning of a relationship that continues today.

1972: Name Change & New Headquarters

Founding partner John E. Hiltz retires and the firm changes its name to Orchard, Papke, Hiltz and McCliment, Inc. Co-founder Ernie Orchard becomes President and continues to develop our culture of acting as trusted advisors to our community clients. The firm moves to a new, larger building, and serves five major Michigan municipal clients still with us today: the cities of Livonia, Ypsilanti, and Farmington and the townships of Superior and Pontiac (now the City of Auburn Hills).

1984: Client Community & Technology Expansions

The firm expands to provide services for county road agencies and we complete our first projects for the Michigan Department of Transportation. We also delve into the new world of computer-aided drafting, launching a Structural Design Group focused on roadway infrastructure the following year. 


1995: Robust Service Growth & Second Office Opening

Our second office in Livonia opens to house our expanding Construction and Geographic Information Systems departments.


2005: Merger Brings Architecture Expertise

The firm expands to Michigan's Upper Peninsula, joining forces with Hitch, Inc. of Houghton, Michigan. The merger brings new service offerings to our clients including architecture and mechanical and electrical engineering services. The office also extends our client community family to include K-12 schools, universities and the federal government.

2008: Nashville Office Opening Grows Firm Regionally

The opening of our Nashville, Tennessee location begins a future of successful professional relationships with the Tennessee Department of Transportation, the city of Nashville and many other cities and municipalities in the firm’s new service region.

2010: Merger Adds Planning & Landscape Architecture

Under the leadership of new President John J. Hiltz, we again expand our geographic reach and diversify our client service offerings through a merger with Columbus, Ohio-based Bird Houk Collaborative. The merger integrates our public-sector focused services to municipalities and agencies with Bird Houk’s architecture, planning, and urban design for both private and public sectors, beginning a new era for our firm as a full-service consultant across multiple (and growing) geographies. 


2015: Firm Expands Further with Northeast Ohio Partnership

OHM Advisors merges with Krock Esser Engineering of Richland, Ohio, expanding the firm's reach to Northeast Ohio and integrating Krock Esser’s municipal engineering, construction management and private sector development services in that region. In addition to a new location, the firm gains a team of professionals that provides complementary services, has shared core values, and aligns with our firm's partnership vision.

2018: Continued Expansion Strengthens Client Services

The firm is now operating in Akron and Cleveland, aligning operations and multidisciplinary staff growth with client needs. The newly-opened Petoskey office strengthens offerings to clients in northern Michigan, historically served by OHM Advisors’ Hancock and mid-Michigan offices. Seventeen employees from the former Northwest Design Group (NDG), a Petoskey-based engineering firm founded more than 36 years ago, initially comprised the local team.

In our Founding Partner's Words
OHM Advisors employees stand at Livonia Drain No. 22 with City Officials.
OHM Advisors Livonia Drain No. 22 - a nine-foot diameter barrel along Plymouth Road.