Celebrating Our 150th Anniversary

Building success with service since 1874

Click to view Booklet

Our retention file of survey plans, dates back to the beginning, in 1874.

Our History

Yerkes Associates was founded by Samuel and John Garrigues in 1874 to provide primarily surveying services to the Philadelphia Main Line property owners, businesses and financial institutions that nurtured the growth of the Montgomery and Delaware County areas during the formative years of the twentieth century. The Company’s home office was located in Bryn Mawr which is centrally located to that growth area.

Milton R. Yerkes became associated with the Company just prior to 1900 and following the retirement of the Garrigues brothers, purchased the firm in 1902 and changed its name to M.R. Yerkes, C.E. Milton Yerkes was the first of four generations of the Yerkes family to oversee its expansion in the five-county southeastern Pennsylvania area. The focal point of the Company throughout its steady growth was to provide survey and civil engineering services to both private and municipal entities developing the Main Line. The Company expanded its services in support of the orderly growth of the area by providing professional planning expertise in the early part of the 20th Century.

John B. Yerkes, Sr. joined the firm in 1933 and the name was changed to M.R. & J. B. Yerkes, Civil Engineers & Land Surveyors. By 1955, growth had progressed steadily and larger office spaces were necessary. The firm moved to Rosemont to occupy three buildings on the Vauclain Estate where its business continued to mature. Another name change to Yerkes Engineering Company was made and additional professional and support staff was added to manage the growing demand for services.

As the Main Line growth expanded into the surrounding western counties, the Company opened an office in 1969 in the Exton area of central Chester County. The Municipal Services Department was expanded to serve municipalities in Chester and Berks Counties and provide the private sector with Civil Engineering, Site Planning and Landscape Architecture. Increased demand for a variety of municipal inspection services allowed the Company to expand its Inspection Group with Certified Code Officials that provide Code compliance reviews and building construction inspection for residential, commercial and industrial construction.

To conform to a growing corporate structure, a name change to the current Yerkes Associates, Inc. was made and the Company consolidated its corporate work force in 1975 to a six acre property in Chester County near the Route 202 and 30 crossroads. The municipal Services Group expanded to serve more than 20 townships and boroughs, and the civil engineering and landscape architecture disciplines grew to provide enhanced services to the private sector.

On May 1, 2017, Cirilli Associates, Inc. acquired “Yerkes” under the leadership of Nick Cirilli, PE, PLS, further enhancing Yerkes’ full-service capability. Despite today’s unsettled times, the future is bright as we continue to provide our clients with efficient, effective quality professional services. To our many, many clients – we are appreciative and grateful that you have given us the opportunity to serve. – Thank you.

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