Adrian Shank, 61, whose family has owned and operated the mill since 1935, owns the water rights to Red Run stream.
A buildup of sediment over four decades left little room for water in the millrace, Shank said.
Shank's grandfather, Wilmer O. Shank, bought the mill from the Shockey family. Adrian Shank's father, Odell J. Shank, took it over. After Odell Shank died in 1973, his wife, Yula, ran the mill until 2000.
Shank worked in the mill until he graduated from Waynesboro High School and left in 1962 for Drexel University, where he earned a degree in electrical engineering. He lives in Odenton, Md., and holds a management position with Northrop Grumman Corp.
The mill, even though its machinery is still in working order, will not run full time again, Shank said.
Once the millrace is cleaned out and filled with water, the mill will become a living history exhibit operated on a limited basis so visitors can learn how a gristmill worked.
"Plans are fluid, but this is a historical treasure. This is what the family wants," he said.
"The mill is well-equipped. Its original equipment could be started right now, but it's not like booting up a computer. There's a lot of quirky stuff in here," he said.
He wants the mill operating by September, when hundreds of members of the Society for the Preservation of Old Mills, or SPOOM, come for a visit.
Anderson's Mill near Mercersburg, Pa., Franklin County's other working gristmill, also is on the SPOOM tour.
A dam in the millrace across the road from the mill creates a small pond that provides a constant flow to the wheel.
Water flows to the wheel through a large pipe. It leaves the wheel through an aqueduct under the mill to the tailrace, where it flows back into Red Run stream in the same clean condition it was in when it entered the mill.
Between the millrace and tailrace there must have been a cacophony of noise when the mill was in full operation.
A labyrinth of belts, pulleys and gears, all run by the water wheel, accepted, cleaned and dried all the corn, wheat, oats, rye and barley that area farmers brought in on their horses and wagons and, later, trucks. The finished product then was conveyed to fourth- and fifth-floor storage bins or ground into flour, meal or animal feed.
Storage capacity was important to the mill, Shank said.
"The farmers had to get their crops into the mill by the fall and the mill needed a large enough supply to be able to grind corn and flour until the next harvest season," he said.
A small building across Amsterdam Road from the mill served as the cooper's shed. Carpenters, or coopers, built the barrels that held the grain that the mill produced. Grain and flour also were bagged by the mill's machinery.
In later years, the mill produced specialty flour for area bakeries, Shank said.
Shank's Mill, which Shank said was built in 1857 by Christian Stouffer, is on the National Register of Historic Places.