Leroy Nelson Houck (1895-1980) was an electrician with the Pennsylvania Water & Power Company.

Houck was born to Alice Tuttle Houck (1872-1950) and Edward A. Houck (1871-1943) in Ravena, New York. He worked as a chauffeur while studying to become an electrician.

From 1917 to 1921, Houck worked at the Upper Hudson Electric and Railroad Co. One of the first major projects he worked on was building the electric plant at Racquette River, New York. In 1921, Houck moved to Baltimore, Maryland, to work for the Pennsylvania Water & Power Company. He began his time at the company managing the substation at the Holtwood facility. He went on to spend the remainder of his career working in the Load Dispatcher's Office.

In 1917, Houck married Margurite Buckman Houck (1893-1990); the couple had three children, two daughters and one son.

Pennsylvania Water & Power Company was established to store, transport, and generate water power for both commercial and manufacturing purposes. The Holtwood facility outside of Lancaster, Pennsylvania, was the first power plant to have both a hydroelectric generator and a coal power generator. The company was originally called McCall’s Ferry Power Co. and was founded in 1905.

The Holtwood Dam was built between 1905 and 1910 along the Susquehanna River, twenty-five miles upstream from the Chesapeake Bay. The original name was the McCalls Ferry Dam. The name was changed to honor two financiers who helped complete the project after the 1907 financial panic in the United States caused the company to default on its bonds. At this time, the dam, powerhouse, and railroad yard were only partially finished. The company reached out to John E. Aldred (1864-1945), a hydroelectric industry pioneer and entrepreneur, for help. Aldred was the president of Shawinigan Falls Power Co. in Canada and president of Consolidated Gas, Electric Light and Power Company in Baltimore. Aldred partnered with Sir Herbert S. Holt (1856-1941), president of Montreal Light, Heat & Power Company, and Edward R. Wood (1866-1941), vice president of Toronto Securities. The company was reorganized as Pennsylvania Water & Power Company. The dam was renamed Holtwood, and the reservoir was named Lake Aldred.

John Abbet Walls (187?-195?) was the chief engineer and later president of the Pennsylvania Water and Power Company. As chief engineer, he oversaw the construction of the dams. A graduate of the Massachusetts Institute of Technology, Walls worked for Aldred at the Shawinigan Falls Power Co. as an assistant engineer in 1901.

In 1925, a coal-fired steam electric station was built next to the hydroelectric plant. From 1925 until 1973, the plant burned coal that was dredged from the river.

To meet the needs of the growing industrial use of electric power, a second dam was built located thirty-two miles upstream from the Chesapeake Bay. Construction on the Safe Harbor Dam began in 1929, and by 1931, power was being generated and delivered. The reservoir, Lake Clarke, extends nine and a half miles upstream near Columbia, Pennsylvania. Sand and coal were dredged from the lake each year between 1954 and 1972.

The Safe Harbor Dam was co-owned by Consolidated Gas Electric Light and Power Company, which owned two-thirds of the company. In 1955, Pennsylvania Power & Light (PP&L) acquired Pennsylvania Water and Power Company. With this purchase, PP&L now became the owner of the Holtwood Dam and one-third owner of the Safe Harbor Dam. PP&L changed its name to PPL Corporation in 2000.