About Us

Callon Dietz has a rich history of surveying throughout Ontario. We begin a typical project by researching available records from many sources to ensure we have first-rate information and evidence to complete the project. We then choose only the best combination of equipment to finish the project safely, accurately and efficiently so that we deliver the best product to our clients.

Callon Dietz started in 1967 as T.O Callon Limited and changed its name when Terry Dietz became a partner. Expanding throughout the province to better service and reach our customers, Callon Dietz has offices in London, North Bay and Ottawa.

Lidar Mapping Illustration


To provide a full range of world-class surveying, mapping and land information services to meet the expectation of domestic and international customers. In business since 1967, Callon Dietz Incorporated Ontario Land Surveyors is proud to be Ontario’s first ISO 9000:2008 registered land surveying company.


Technology powered by experience.

Callon Dietz Incorporated has provided land-surveying services to Southwestern Ontario since 1967. Established as the T.O. Callon Company, the firm became Callon Dietz Incorporated Ontario Land Surveyors in 1991.

Today, Callon Dietz partners on a wide variety of projects including gas line and other above-ground and underground services, highway reconstruction programs, subdivision and condominium surveys, digital terrain modelling and mapping. While London, Ontario, Canada is our base, we do business across Ontario.

Committed to quality.

By its very nature, surveying is about quality management. That’s why Callon Dietz developed a rigorous quality assurance process that is continually reviewed by external auditors to ensure compliance with ISO quality systems standards.

In 1998, we achieved ISO 9000 certification. Callon Dietz was one of the first in Canada, to achieve this internationally recognized designation.

What does this mean for our customers?

Callon Dietz is registered with the Ontario Ministry of Transportation’s Registry, Appraisal and Qualification System (RAQS). This system registers, prequalifies and tracks consultant performance, determining eligibility to bid for the MTO contracts.

In addition to ISO 9001:2008 certification, An Ontario Land Surveyor directly supervises all work done at Callon Dietz. They check all plans and a regular schedule of field inspections ensures that only the highest quality surveys reach you. We routinely audit all facets of our own practice and hire external auditors to verify our procedures.


Training and Safety

Our employees are our most important resource. Technical staff are graduates of university or community college surveying programs. Our staff keep up with technology through continuing education and have current first aid, traffic control and WHMIS training, Crew Chiefs have been trained under the Occupational Health and Safety Act. Safety is our first priority on all projects.


We are always interested in talking to highly skilled individuals who share our mission and values. We welcome resumes from qualified applicants.

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Put your project in motion today and call on Callon Dietz to set up an appointment with one of our responsive and knowledgeable staff.

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© 2018 Callon Dietz. All Rights Reserved

Callon Dietz Incorporated
41 Adelaide St. North, Unit 1
London, Ontario  N6B 3P4

591 Main St. East, Unit 102
North Bay, Ontario  P1B 1B7

40 Bennett Street, Unit B
Carleton Place, Ontario  K7C 4J9