LAKE ARIEL, PA — Did you know that thousands of years ago, before the dam was built in 1926 to create Lake Wallenpaupack in the Pocono Mountains of Pennsylvania, it used to be a much bigger lake that was carved out by glaciers? Bernadine Lennon, program chair of the Greene-Dreher Historical Society, and D.J. Roberts, local historian and former trustee for the Lacawac Sanctuary, shared this and other information in honor of the 100th anniversary of Lake Wallenpaupack and the 60th anniversary of Lacawac Sanctuary. 

Their presentation on September 26 at Lacawac looked back 10,000 years on the evolution of Lake Wallenpaupack from a geological and historical perspective.

Glacial periods

Lennon said that between 17,000 and 20,000 years ago in the Wallenpaupack Valley area, there was an enormous lake, formed by the Wisconsin glacier. This glacier was a large sheet of ice the size of a continent that extended into northwestern and northeastern Pennsylvania.  

As the glacier receded, it left hilly, rocky terrain, eroded the land, and carved out a basin that filled with meltwater and rainwater to create a glacial lake.  An ancient river flowing through the valley before the Wisconsin glacier combined with the glacial melt to form a lake 200 to 300 feet deep. (See image, center right.)

Over thousands of years, water flowing from the river and lake eroded glacial deposits in the area where the dam is now located, forming the Wallenpaupack Falls (or High Falls at Wilsonville). (See image,  lower right).  Over time, the valley lake became the Wallenpaupack River, which was dammed in 1926 to create Lake Wallenpaupack. 

In addition to the valley lake, the glacier created 50 lakes in Pennsylvania, 42 in northeastern Pennsylvania (including Bruce Lake, Pike County and Lake Lacawac, Wayne County) and eight in northwestern Pennsylvania.

Native Americans and early settlers

Lennon noted that ancient hunter-gatherers from Asia, known as Paleoindians (or Clovis people), lived in the region 10,000 to 13,000 years ago and grew into distinct Native American cultures. One of them was the Lenape, and their land became known as Lenapehoking—Land of the Lenape.  The Lenape and other indigenous tribes created 131 foot trails through Pennsylvania, which were used for hundreds of years to trade with other Native American tribes, forage for food, and hunt game. 

A trail in the Wallenpaupack Valley area was the Wyoming-Minisink Trail, connecting Minisink Island in the Upper Delaware River to the Susquehanna River. 

In the 18th century, settlers came to the Wallenpaupack Valley from Europe and New England, especially Connecticut, due to a shortage of fertile, affordable land elsewhere.  Most had small homesteads with farm animals, vegetable gardens and orchards.  A small gristmill and sawmill were built at the High Falls, where the Lake Wallenpaupack dam is located.

By the 19th century, commercial sawmills, wood factories, leather tanneries and large gristmills were operating on the Wallenpaupack River. Five major industries developed in Hawley that relied on water power from the Wallenpaupack River and the falls: electrical power, silk/textile manufacturing, cut glass, gristmills and leather tanneries. 

The current Lake Wallenpaupack Dam

By the early 20th century, the hidden potential of the Wallenpaupack River had yet to be realized. The creation of the dam in 1926 changed the region dramatically.

Roberts said that Colonel Louis Arthur Watres, an industrialist in the region, was the driving force behind the creation of a dam that could harness the economic and water power of the Wallenpaupack River and the falls. By 1913, he and his partners bought 12,000 acres of land along the Wallenpaupack River to create a dam. They organized two companies: the Pennsylvania Realty and Investment Company to buy the land for the Wallenpaupack Project; and the Pennsylvania, New York and New Jersey Power Company to build it. 

Land purchased by Watres included what is now known as Lacawac Sanctuary, a scientific and educational facility in Lake Ariel.  It was founded by his grandson, Arthur Watres.

When the dam was built, workers used sandy gravel deposited by the Wisconsin Glacier to mix with the concrete walls being built for the dam. It runs over 1,280 feet, almost a quarter of a mile, and is 70 feet high at its maximum.

According to Roberts, “The creation of Lake Wallenpaupack increased Pennsylvania Power and Light’s (PPL) capacity about 25 percent. Today, the big lake represents a fraction of a percent of PPL’s generating capacity and is, however, efficient in that it kicks in automatically whenever peak power is demanded, a critical point for electric suppliers.” Ownership has changed several times and Brookfield Renewable Partners now owns the lake and generates electricity.

The shoreline around Lake Wallenpaupack has yielded many Indian artifacts such as arrowheads, spear points, tomahawks, mortars and pestles. Many of these can be seen at the Visitor’s Center and at the Wallenpaupack Environmental Learning Center in Hawley.

The Greene-Dreher Historical Society (www.greenedreherhs.org) is located at 465 South Sterling Road in South Sterling. For information on group presentations, contact balennon@ATT.net.  The Lacawac Sanctuary’s address is 94 Sanctuary Road in Lake Ariel. For information on upcoming events, visit www.lacawac.org.