Mercer County Engineer's Office

About Us


Mercer County has an infrastructure investment in county owned bridges and dams of over 100 million dollars. There are 247 bridges located throughout the county. Of the 247 bridges, three are owned jointly with Crawford County, two are owned jointly with Trumbull County, and one is owned jointly with Coolspring township. A number of municipalities also have maintenance responsibilities for certain bridge features such as sidewalks and lighting.

The Engineer's office is responsible for the inspection, maintenance and operation of these facilities, as well as the design and construction management of improvement projects.


The County complies with the National Bridge Inspection Standards as detailed in the Code of Federal Regulations 23 Highways Part 650, Subpart C.

Each bridge is inspected at a frequency of not less than 2 years by inspectors meeting the qualifications stated in 650.307. Annual inspections are required to ensure the continued safe operation, maintenance and stability of the structure thus protecting life and property.

The inspection consists of a comprehensive visual or hands on inspection, accompanied by photographs, which indicates the conditions prevailing at each bridge. Measurements are routinely made to assess integrity of the structure.

All phases of design for new structures and rehabilitated structures are completed by staff professionals. In-house staff also performs construction inspection quality assurance and quantity documentation.