According to the United States Census Bureau, the township has a total area of , of which , or 0.02%, is water. The township is primarily drained by Conococheague Creek, which rises on South Mountain and enters the township at Caledonia Park, flowing west then south to Chambersburg and ultimately to the Potomac River. The northern corner of the township drains north via Rowe Run to Conodoguinet Creek, a tributary of the Susquehanna River.