Safe Harbor Dam
Encyclopedia
The Safe Harbor Dam is a concrete gravity dam
on the lower Susquehanna River
with an associated hydroelectric power station
. It is the most northerly and last of three Great Depression
-era
public electrification projects'
hydroelectric dams and was constructed between 1 April 1930 and 7 December 1931. It created a long and relatively shallow lake along the upper stretch of the Conejohela Valley known as Lake Clarke
. The creation of the lake shrunk the upper Conejohela Flats
in size.
which saw annual inundations all the way down into Maryland
at the confluence with the Potomac at the headwaters of Chesapeake Bay
, 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 and many of those habitats effectively created difficult walking and horseback terrains which stifled east-west crossing of the lower Susquehanna in colonial Pennsylvania
-Maryland
spurring the 1730 opening of the historic Wright's Ferry
and (later the first two) Columbia-Wrightsville Bridge
s, once believed to be the longest covered bridges in the world.
with the Susquehanna, about 7 miles downstream of Washington Boro
, Pennsylvania
, which at mid-river is figured more or less the center of Lake Clarke
species and so loss in bird-small animal habitat was replaced by and large, in freshwater marine habitats.
and Constellation Energy
. (York Haven Hydroelectric Station is the most northerly and last of four hydroelectric dams constructed on the lower Susquehanna River).
for railroad use by Amtrak
and SEPTA, but also can be connected to a motor-generator
to generate additional 60 Hz power. The rest of the units generate 60 Hz, three-phase, power. Safe Harbor can generate 417.5 megawatts of hydroelectric power. Power from Safe Harbor is dispatched through PJM Interconnection
, one of many Regional Transmission Organization
s feeding the nations power grids.
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.
Dam
A dam is a barrier that impounds water or underground streams. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. Hydropower and pumped-storage hydroelectricity are...
on the lower Susquehanna River
Susquehanna River
The Susquehanna River is a river located in the northeastern United States. At long, it is the longest river on the American east coast that drains into the Atlantic Ocean, and with its watershed it is the 16th largest river in the United States, and the longest river in the continental United...
with an associated hydroelectric power station
Power station
A power station is an industrial facility for the generation of electric energy....
. It is the most northerly and last of three Great Depression
Great Depression
The Great Depression was a severe worldwide economic depression in the decade preceding World War II. The timing of the Great Depression varied across nations, but in most countries it started in about 1929 and lasted until the late 1930s or early 1940s...
-era
Era
An era is a commonly used word for long period of time. When used in science, for example geology, eras denote clearly defined periods of time of arbitrary but well defined length, such as for example the Mesozoic era from 252 Ma–66 Ma, delimited by a start event and an end event. When used in...
public electrification projects'
Electrification
Electrification originally referred to the build out of the electrical generating and distribution systems which occurred in the United States, England and other countries from the mid 1880's until around 1940 and is in progress in developing countries. This also included the change over from line...
hydroelectric dams and was constructed between 1 April 1930 and 7 December 1931. It created a long and relatively shallow lake along the upper stretch of the Conejohela Valley known as Lake Clarke
Lake Clarke, Pennsylvania
Lake Clarke, 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 centered within the Conejohela Valley approximately ...
. The creation of the lake shrunk the upper Conejohela Flats
Conejohela Flats
The Conejohela Flats are a group of islands in the flooded Conejohela Valley, a large floodplain along the southernmost 30 miles of the Susquehanna River in Pennsylvania and Maryland in the United States...
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 floodplainFloodplain
A floodplain, or flood plain, is a flat or nearly flat land adjacent a stream or river that stretches from the banks of its channel to the base of the enclosing valley walls and experiences flooding during periods of high discharge...
which saw annual inundations all the way down into Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
at the confluence with the Potomac at the headwaters of Chesapeake Bay
Chesapeake Bay
The Chesapeake Bay is the largest estuary in the United States. It lies off the Atlantic Ocean, surrounded by Maryland and Virginia. The Chesapeake Bay's drainage basin covers in the District of Columbia and parts of six states: New York, Pennsylvania, Delaware, Maryland, Virginia, and West...
, 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 and many of those habitats effectively created difficult walking and horseback terrains which stifled east-west crossing of the lower Susquehanna in colonial Pennsylvania
Province of Pennsylvania
The Province of Pennsylvania, also known as Pennsylvania Colony, was founded in British America by William Penn on March 4, 1681 as dictated in a royal charter granted by King Charles II...
-Maryland
Province of Maryland
The Province of Maryland was an English and later British colony in North America that existed from 1632 until 1776, when it joined the other twelve of the Thirteen Colonies in rebellion against Great Britain and became the U.S...
spurring the 1730 opening of the historic Wright's Ferry
Wright's Ferry
Wright's Ferry was an animal powered ferry established by John Wright in 1730, and the very first means of crossing the wide unfriendly Susquehanna in the counties of the lower half of the state of Pennsylvaniaand directly triggered Cresap's War between the Province of Maryland and Pennsylvania...
and (later the first two) Columbia-Wrightsville Bridge
Columbia-Wrightsville Bridge
The Columbia–Wrightsville Bridge, officially the Veterans Memorial Bridge, spanning the Susquehanna River between Columbia and Wrightsville, Pennsylvania, is commonly associated with the name “Columbia–Wrightsville Bridge,” although five other former and present-day bridges share this...
s, once believed to be the longest covered bridges in the world.
Siting
The dam is located just above the confluence of the Conestoga RiverConestoga River
The Conestoga River, also referred to as Conestoga Creek, is a tributary of the Susquehanna River flowing through the center of Lancaster County, Pennsylvania.-Geography:...
with the Susquehanna, about 7 miles downstream of Washington Boro
Washington Boro, Pennsylvania
Washington Boro is an unincorporated community in Manor Township, Lancaster County, Pennsylvania, United States, along the Susquehanna River. The zip code here is 17582...
, Pennsylvania
Pennsylvania
The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...
, which at mid-river is figured more or less the center of Lake Clarke
Lake Clarke, Pennsylvania
Lake Clarke, 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 centered within the Conejohela Valley approximately ...
Game fish
Game fish are fish pursued for sport by recreational anglers. They can be freshwater or marine fish. Game fish can be eaten after being caught, though increasingly anglers practise catch and release to improve fish populations. Some game fish are also targeted commercially, particularly...
species and so loss in bird-small animal habitat was replaced by and large, in freshwater marine habitats.
Operating company
The facility is operated by the Safe Harbor Water Power Corporation, which is owned by PPL Holtwood, LLC and Constellation Power Source Generation, Inc., which are subsidiaries of PPLPPL (utility)
PPL, formerly known as PP&L or Pennsylvania Power and Light, is an energy company headquartered in Allentown, Pennsylvania, USA. It currently controls about 19,000 megawatts of electrical generating capacity in the United States, primarily in Pennsylvania and Montana, and delivers electricity to...
and Constellation Energy
Constellation Energy
Constellation Energy, headquartered in Baltimore, Maryland, is an energy producer, trader, and distributor. The company operates over 35 power plants in 11 states under its operating company Constellation Commodities Group and/or Constellation Generation Group...
. (York Haven Hydroelectric Station is the most northerly and last of four hydroelectric dams constructed on the lower Susquehanna River).
Planning and Construction
Planning for the construction of the Safe Harbor dam started in 1929 and construction started 1 April 1930. The dam was completed and closed its gates for the first time on 29 September 1931. The first power was generated on 7 December 1931 and the last of the original seven turbine generator units came on-line on 14 October 1940. Expansion of the generation capacity started planning in 1981. Construction started 12 April 1982 and the 5 new turbine generator units came on-line between 13 April 1985 and 12 April 1986. Units 1 and 2 generate 25 Hz single phase power25Hz Power Transmission System
Amtrak's 25 Hz Traction Power System is a traction power grid operated by Amtrak along the southern portion of its Northeast Corridor : the 363 route miles between Washington, D.C. and New York City and the 104 route miles between Philadelphia and Harrisburg, Pennsylvania. The Pennsylvania...
for railroad use by Amtrak
Amtrak
The National Railroad Passenger Corporation, doing business as Amtrak , is a government-owned corporation that was organized on May 1, 1971, to provide intercity passenger train service in the United States. "Amtrak" is a portmanteau of the words "America" and "track". It is headquartered at Union...
and SEPTA, but also can be connected to a motor-generator
Motor-generator
A motor-generator is a device for converting electrical power to another form. Motor-generator sets are used to convert frequency, voltage, or phase of power. They may also be used to isolate electrical loads from the electrical power supply line...
to generate additional 60 Hz power. The rest of the units generate 60 Hz, three-phase, power. Safe Harbor can generate 417.5 megawatts of hydroelectric power. Power from Safe Harbor is dispatched through PJM Interconnection
PJM Interconnection
PJM Interconnection LLC is a Regional Transmission Organization which is part of the Eastern Interconnection grid operating an electric transmission system serving all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee,...
, one of many Regional Transmission Organization
Regional Transmission Organization
A regional transmission organization in the United States is an organization that is responsible for moving electricity over large interstate areas. Like a transmission system operator , an RTO coordinates, controls and monitors an electricity transmission grid that is larger with much higher...
s feeding the nations power grids.
Key events
On 18 May 2001, President George W. BushGeorge W. Bush
George Walker Bush is an American politician who served as the 43rd President of the United States, from 2001 to 2009. Before that, he was the 46th Governor of Texas, having served from 1995 to 2000....
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.
See also
- Conowingo DamConowingo DamThe Conowingo Dam is a large hydroelectric dam in the Lower Susquehanna River. The dam, one of the largest non-federal hydroelectric dams in the US, is classified as a medium height, masonry gravity type dam...
- List of dams and reservoirs of the Susquehanna River
- SEPTA's 25 Hz Traction Power SystemSEPTA's 25 Hz Traction Power SystemSEPTA operates a 25 Hz traction power system in the vicinity of Philadelphia, Pennsylvania that it inherited from the Reading Railroad. This system is separate but similar to the system designed by the Pennsylvania Railroad which is now operated by Amtrak. SEPTA's trains can run over either...
- Susquehanna river damsSusquehanna river damsThe Susquehanna River, in the Mid-Atlantic States of the USA, has a collection of dams. These dams are used for power generation, flood control, navigation and recreation. These dams have local and regional environmental impacts on the river and the Chesapeake Bay, both positive and negative.-...