The Highway Division within DOT&I is responsible for maintaining the County's Infrastructure under the direction of the Engineering Division. It is comprised of five (5) subdivisions: Roads, Bridges, Traffic, Mosquito Control and Shade Tree Divisions. The Roads Division maintains nearly 180 miles, (425 lane miles) of county roadway and is responsible for road repairs, roadway resurfacing and plowing. The Bridge Division is responsible for ensuring the structural integrity of over 850 structures including bridges, culverts, inlets and guide rails. The Traffic Division maintains and installs signs, traffic signals, and pavement markings on the county roadway system and also provides assistance to municipalities with no in-house traffic signal maintenance capabilities. The Shade Tree Division is responsible for trimming, planting and removing trees within the county right of way where necessary. The Mosquito Control Division is responsible for controlling the threat of disease carrying mosquito populations within Mercer County. The five subdivision of the Highway Department all work effectively together to provide the highest level of service and safety to all citizens of the County.