The Safe Harbor Dam (also Safe Harbor Hydroelectric Station) is a concrete gravity

dam A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use ...

, with an associated

hydroelectric Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and ...

power station A power station, also referred to as a power plant and sometimes generating station or generating plant, is an industrial facility for the generation of electric power. Power stations are generally connected to an electrical grid. Many p ...

, on the lower

Susquehanna River The Susquehanna River (; Lenape: Siskëwahane) is a major river located in the Mid-Atlantic region of the United States, overlapping between the lower Northeast and the Upland South. At long, it is the longest river on the East Coast of the ...

. It is the most northerly and last of three

Great Depression The Great Depression (19291939) was an economic shock that impacted most countries across the world. It was a period of economic depression that became evident after a major fall in stock prices in the United States. The economic contagio ...

era An era is a span of time defined for the purposes of chronology or historiography, as in the regnal eras in the history of a given monarchy, a calendar era used for a given calendar, or the geological eras defined for the history of Earth. Comp ...

public In public relations and communication science, publics are groups of individual people, and the public (a.k.a. the general public) is the totality of such groupings. This is a different concept to the sociological concept of the ''Öffentlichkei ...

electrification projects'

hydroelectric dams Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined an ...

, and was constructed between April 1, 1930 and December 7, 1931. It created a long and relatively shallow lake, known as

Lake Clarke Lake Clarke in Pennsylvania is a man-made lake along the Susquehanna River formed by the Safe Harbor Dam, a public works project of the 1930s Great Depression and one of the electrification projects of the New Deal. It is approximately long cent ...

, along the upper stretch of the

Conejohela Valley The Conejohela Flats are a group of islands in the flooded Conejohela Valley, a large floodplain along the southernmost 30 miles (50 km) of the Susquehanna River in Pennsylvania and Maryland in the United States. The valley was flooded primaril ...

. The creation of the lake shrank the upper

Conejohela Flats The Conejohela Flats are a group of islands in the flooded Conejohela Valley, a large floodplain along the southernmost 30 miles (50 km) of the Susquehanna River in Pennsylvania and Maryland in the United States. The valley was flooded primari ...

in size.

Base terrains

The mixed marshy terrain of the Conejohela Valley contained rapids and small waterfalls, wetlands, and thick woods along both sides of the river within a ten-year

floodplain A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.Goudi ...

which saw annual inundations all the way down into

Maryland Maryland ( ) is a state in the Mid-Atlantic region of the United States. It shares borders with Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware and the Atlantic Ocean to ...

at the headwaters of

Chesapeake Bay The Chesapeake Bay ( ) is the largest estuary in the United States. The Bay is located in the Mid-Atlantic (United States), Mid-Atlantic region and is primarily separated from the Atlantic Ocean by the Delmarva Peninsula (including the parts: the ...

, and experienced catastrophic floods regularly (the meaning of a ten-year floodplain). The varied terrain created many interface zones biologically nurturing a great many species. Many of those habitats effectively created difficult walking and horseback terrains, which stifled east-west crossing of the lower Susquehanna in colonial

Pennsylvania Pennsylvania (; ( Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, ...

, spurring the 1730 opening of the historic

Wright's Ferry Wright's Ferry was a Pennsylvania Colony settlement established by John Wright in 1726, that grew up around the site of an important Inn and Pub anchoring the eastern end of a popular animal powered ferry (1730–1901) and now a historic part of ...

and (later the first two) Columbia-Wrightsville Bridges, once believed to be the longest covered bridges in the world.

Siting

The dam is located just above the confluence of the

Conestoga River The Conestoga River, also referred to as Conestoga Creek, is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map, accessed August 8, 2011 tributary of the Susquehanna River flowing through the cente ...

with the Susquehanna, about downstream of Washington Boro,

, which at mid-river is figured more or less the center of

created by the damwhich has become very popular for water sports and fishing. Ecologically, the varying depth of inundated islands on the bottom of the lake create a succession of valuable varied habitats that support numerous freshwater feeder fish, pan fish, and large predatory

game fish Game fish, sport fish or quarry refer to popular fish pursued by recreational anglers, and can be freshwater or saltwater fish. Game fish can be eaten after being caught, or released after capture. Some game fish are also targeted commerciall ...

species. Thus, bird-small animal habitat that was lost was replaced, by and large, by freshwater lacustrine habitats.

Operating company

LS Power Group purchased PPL's share in 2011, and was subsequently purchased in March 2014 by

Brookfield Renewable Brookfield Renewable Partners L.P. is a publicly traded limited partnership that owns and operates renewable power assets, with corporate headquarters in Toronto, Ontario, Canada. It is 60% owned by Brookfield Asset Management. As of the end of ...

Inc. In May 2014, Brookfield purchased Exelon's share, gaining full ownership. The Safe Harbor Water Power Corporation operates the dam and power plant.

Planning and construction

Planning for the construction of the Safe Harbor Dam started in 1929, and construction started on April 1, 1930. The dam was completed and closed its gates for the first time on September 29, 1931. The first power was generated on December 7, 1931, and the last of the original seven turbine generator units came on-line on October 14, 1940. Planning for expansion of the generation capacity started in 1981. Construction started on April 12, 1982, and the five new turbine generator units came on-line between April 13, 1985 and April 12, 1986. Units 1 and 2 are

Kaplan turbine The Kaplan turbine is a propeller-type water turbine which has adjustable blades. It was developed in 1913 by Austrian professor Viktor Kaplan, who combined automatically adjusted propeller blades with automatically adjusted wicket gates to ach ...

s connected to

single-phase generator Single-phase generator (also known as single-phase alternator) is an alternating current electrical generator that produces a single, continuously alternating voltage. Single-phase generators can be used to generate power in single-phase electric p ...

s to produce 25 Hz

single-phase electric power In electrical engineering, single-phase electric power (abbreviated 1φ) is the distribution of alternating current electric power using a system in which all the voltages of the supply vary in unison. Single-phase distribution is used when load ...

for railroad use by

Amtrak The National Railroad Passenger Corporation, Trade name, doing business as Amtrak () , is the national Passenger train, passenger railroad company of the United States. It operates inter-city rail service in 46 of the 48 contiguous United Stat ...

and

SEPTA The Southeastern Pennsylvania Transportation Authority (SEPTA) is a regional public transportation authority that operates bus, rapid transit, commuter rail, light rail, and electric trolleybus services for nearly 4 million people in five coun ...

, but also can be connected to a motor-generator to convert any spare 25 Hz power to 60 Hz. The rest of the units generate 60 Hz, three-phase power. Safe Harbor can generate 417.5 megawatts of

hydroelectric power Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies one sixth of the world's electricity, almost 4500 TWh in 2020, which is more than all other renewable sources combined and ...

. Power from Safe Harbor is dispatched through

PJM Interconnection PJM Interconnection LLC (PJM) is a regional transmission organization (RTO) in the United States. It is part of the Eastern Interconnection grid operating an electric transmission system serving all or parts of Delaware, Illinois, Indiana, Kentu ...

, one of many

regional transmission organization A regional transmission organization (RTO) in the United States is an electric power transmission system operator (TSO) that coordinates, controls, and monitors a multi-state electric grid. The transfer of electricity between states is considered i ...

s feeding the nations power grids.

Key events

On May 18, 2001, President

George W. Bush George Walker Bush (born July 6, 1946) is an American politician who served as the 43rd president of the United States from 2001 to 2009. A member of the Republican Party, Bush family, and son of the 41st president George H. W. Bush, he ...

visited the Safe Harbor Hydroelectric plant to expound on his just-unveiled National Energy Policy. Safe Harbor was chosen as an example of government, corporate, and environmental groups working together in energy generation. In 2001, Safe Harbor Water Power Corporation won the Governor's Award for Environmental Excellence. The award citation states that Safe Harbor had removed over 11,000 tons of debris from the river and was able to recycle almost all of it.

References

External links

{{Commons category
Safe Harbor Water Power Company's web site
Dams in Pennsylvania Dams on the Susquehanna River United States power company dams Dams completed in 1931 Energy infrastructure completed in 1931 Hydroelectric power plants in Pennsylvania Buildings and structures in Lancaster County, Pennsylvania Buildings and structures in York County, Pennsylvania