Saint Petersburg Dam
Encyclopedia
The Saint Petersburg Flood Prevention Facility Complex , unofficially the Saint Petersburg Dam, is a 25 km (15.5 mi) complex of dams for flood control
Flood control
In communications, flood control is a feature of many communication protocols designed to prevent overwhelming of a destination receiver. Such controls can be implemented either in software or in hardware, and will often request that the message be resent after the receiver has finished...

 near Saint Petersburg
Saint Petersburg
Saint Petersburg is a city and a federal subject of Russia located on the Neva River at the head of the Gulf of Finland on the Baltic Sea...

, Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...

. The dam extends from Lomonosov
Lomonosov, Russia
Lomonosov is a municipal town in Petrodvortsovy District of the federal city of St. Petersburg, Russia, situated on the southern coast of the Gulf of Finland, west of St. Petersburg proper. Population:...

 northward to Kotlin Island
Kotlin Island
Kotlin is a Russian island, located near the head of the Gulf of Finland, west of Saint Petersburg in the Baltic Sea. Kotlin separates the Neva Bay from the rest of the gulf...

 (and the city of Kronstadt
Kronstadt
Kronstadt , also spelled Kronshtadt, Cronstadt |crown]]" and Stadt for "city"); is a municipal town in Kronshtadtsky District of the federal city of St. Petersburg, Russia, located on Kotlin Island, west of Saint Petersburg proper near the head of the Gulf of Finland. Population: It is also...

), then turns east toward Cape Lisiy Nos near Sestroretsk
Sestroretsk
Sestroretsk is a municipal town in Kurortny District of the federal city of St. Petersburg, Russia, located on the shores of the Gulf of Finland, the Sestra River and the Sestroretskiy Lake northwest of St. Petersburg...

.

The complex is intended to protect Saint Petersburg from storm surge
Storm surge
A storm surge is an offshore rise of water associated with a low pressure weather system, typically tropical cyclones and strong extratropical cyclones. Storm surges are caused primarily by high winds pushing on the ocean's surface. The wind causes the water to pile up higher than the ordinary sea...

s by separating the Neva Bay
Neva Bay
The Neva Bay , also known as the Gulf of Kronstadt, is the easternmost part of the Gulf of Finland between Kotlin Island and the Neva River estuary where the city of St. Petersburg is sited....

 from the rest of the Gulf of Finland
Gulf of Finland
The Gulf of Finland is the easternmost arm of the Baltic Sea. It extends between Finland and Estonia all the way to Saint Petersburg in Russia, where the river Neva drains into it. Other major cities around the gulf include Helsinki and Tallinn...

. Historically, the storm surges from the gulf had caused over 300 floods in the city
Floods in Saint Petersburg
Floods in Saint Petersburg refer to a rise of water on the territory of St. Petersburg, a major city in Russia and its former capital. They are usually caused by the overflow of the delta of Neva River and surging water in the eastern part of Neva Bay but sometimes caused by melting snow...

, several of which had a massive devastating effect. The dam has the capability to protect the city from water rising up to 5 m (16.4 ft). Its first use to hold back the incoming Baltic water into Neva bay took place in late November of 2011 and had result in decrease of water rise to 1.3 masl
Meters above sea level
Meters above sea Level is a standard metric measurement of the elevation of a location in reference to historic mean sea level; the determination of what actually constitutes mean sea level over time however, may be determined by other parameters, such as the effects of climate history and climate...

, that is below flood level equal to 1.6 masl.

The construction of the flood prevention complex started in 1978 and became one of the longest construction projects in Russia. After a protracted halt in the 1990s and early 2000s, construction was resumed in 2005 due to the intervention of Russia's President Vladimir Putin
Vladimir Putin
Vladimir Vladimirovich Putin served as the second President of the Russian Federation and is the current Prime Minister of Russia, as well as chairman of United Russia and Chairman of the Council of Ministers of the Union of Russia and Belarus. He became acting President on 31 December 1999, when...

, a native of Saint Petersburg. Putin finally inaugurated the finished complex in 2011, when all the facilities at the southern part of the dam were completed, along with the 1.2 km (0.745647283979768 mi) long underwater roadway tunnel below the main southern lock, the longest undersea tunnel in Russia.

Over 30 water purification installations are placed around the dam, a part of a larger program to clean the water in the Neva Bay. The dam tunnel is also the last completed part of the Saint Petersburg Ring Road
Saint Petersburg Ring Road
The Saint Petersburg Ring Road is an 88-mile orbital freeway encircling Saint Petersburg, Russia. It is the only beltway around the city. The St. Petersburg Ring Road in the Russian road numbering system is listed as the federal public road A-118.-Construction:The need for the construction of a...

. The northern and southern parts of the dam act like two giant bridges and provide an easy access from mainland to Kotlin Island and Kronstadt.

Specifications

The dam was constructed across the Gulf of Finland
Gulf of Finland
The Gulf of Finland is the easternmost arm of the Baltic Sea. It extends between Finland and Estonia all the way to Saint Petersburg in Russia, where the river Neva drains into it. Other major cities around the gulf include Helsinki and Tallinn...

, with the island of Kotlin (Kronstadt) at its centre. It extends for 25.4 km (15.8 mi) and stands 8 m (26.2 ft) above water level. It has two large openings for shipping, which can be closed when floods threaten. Construction began in 1980 and stalled in the political and economic upheavals of the 1990s. The main benefit that most people cite is not flood control but rather improved traffic flow, as the dam completes the Saint Petersburg Ring Road
Saint Petersburg Ring Road
The Saint Petersburg Ring Road is an 88-mile orbital freeway encircling Saint Petersburg, Russia. It is the only beltway around the city. The St. Petersburg Ring Road in the Russian road numbering system is listed as the federal public road A-118.-Construction:The need for the construction of a...

.

Floods on the Neva

Saint Petersburg suffers from frequent floods (more than 340 in recorded history), some being natural disaster
Natural disaster
A natural disaster is the effect of a natural hazard . It leads to financial, environmental or human losses...

s. It is situated on drained marshlands, isles and lowlands in the estuary
Estuary
An estuary is a partly enclosed coastal body of water with one or more rivers or streams flowing into it, and with a free connection to the open sea....

 of the Neva River, where flooding is common. Flow from Lake Ladoga
Lake Ladoga
Lake Ladoga is a freshwater lake located in the Republic of Karelia and Leningrad Oblast in northwestern Russia, not far from Saint Petersburg. It is the largest lake in Europe, and the 14th largest lake by area in the world.-Geography:...

 is significant and the Neva's current is rapid, but flooding is generally caused by water backing up the Neva from its outlet, the Gulf of Finland
Gulf of Finland
The Gulf of Finland is the easternmost arm of the Baltic Sea. It extends between Finland and Estonia all the way to Saint Petersburg in Russia, where the river Neva drains into it. Other major cities around the gulf include Helsinki and Tallinn...

. Most rivers flood in periods of exceptionally high flow, but the Neva typically floods in late autumn.

In the early literature, high winds from the Gulf of Finland were often cited as the cause of Neva flooding, but scientists now understand the more complex hydrometeorological
Hydrometeorology
Hydrometeorology is a branch of meteorology and hydrology that studies the transfer of water and energy between the land surface and the lower atmosphere....

 chain of events behind it. A low-pressure region in the North Atlantic moves onshore, giving rise to cyclonic
Cyclone
In meteorology, a cyclone is an area of closed, circular fluid motion rotating in the same direction as the Earth. This is usually characterized by inward spiraling winds that rotate anticlockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere of the Earth. Most large-scale...

 lows on the Baltic Sea
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...

. The low pressure of the cyclone draws greater-than-normal quantities of water into the virtually land-locked Baltic. As the cyclone continues inland, long low-frequency seiche
Seiche
A seiche is a standing wave in an enclosed or partially enclosed body of water. Seiches and seiche-related phenomena have been observed on lakes, reservoirs, swimming pools, bays, harbors and seas...

 waves are established in the Baltic. When the waves reach the narrow and shallow Neva Bay, they become much higher, ultimately breaching the Neva embankments.

The worst such flood occurred on November 19, 1824, when the water level rose 4.21 m (13.8 ft) above normal. The playwright Alexander Griboyedov wrote, "The embankments of the various canals had disappeared and all the canals had united into one. Hundred-year-old trees in the Summer Garden
Summer Garden
The Summer Garden occupies an island between the Fontanka, Moika, and the Swan Canal in Saint Petersburg and shares its name with the adjacent Summer Palace of Peter the Great.-Original:...

 were ripped from the ground and lying in rows, roots upward.
" When the waters receded 569 people were dead, with thousands more injured or made ill – more than 300 buildings had been washed away. The 1824 inundation is the setting for Alexander Pushkin's famous poem, The Bronze Horseman
The Bronze Horseman (poem)
The Bronze Horseman: A Petersburg Tale is a narrative poem written by Aleksandr Pushkin in 1833 about the equestrian statue of Peter the Great in Saint Petersburg. Widely considered to be Pushkin's most successful narrative poem, "The Bronze Horseman" has had a lasting impact on Russian...

(1834). Other disastrous floods took place in 1777 and 1924. One of the most recent floods occurred on October 18–19, 1998, when the water level rose to 2.2 m (7.2 ft).

Project

For years, prominent scientists and statesmen of imperial Russia developed various plans for flood protection, and the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 implemented the idea. The flood of 1955 finally made it clear that the city needed a protection dam. Many options were considered before the Soviet government decided on a 25.4 km (15.8 mi) complex of 11 dams, including a six-lane highway on the top.

The project was begun in 1979, and construction continued through 1995, at which point the dam was around 70% complete, when due to difficulties obtaining financing after the fall of the Soviet Union the project was suspended until 2005, when Prime Minister Vladimir Putin
Vladimir Putin
Vladimir Vladimirovich Putin served as the second President of the Russian Federation and is the current Prime Minister of Russia, as well as chairman of United Russia and Chairman of the Council of Ministers of the Union of Russia and Belarus. He became acting President on 31 December 1999, when...

 ordered its resumption. Construction was completed in 2011, and the formal opening of the complex was on 12 August 2011. At the opening ceremony, Putin said that the completion of the project was a "historic event" and meant that Saint Petersburg "is not just protected from floods, the ecological situation also improved."

The entire project cost roughly 109 billion ruble
Ruble
The ruble or rouble is a unit of currency. Currently, the currency units of Belarus, Russia, Abkhazia, South Ossetia and Transnistria, and, in the past, the currency units of several other countries, notably countries influenced by Russia and the Soviet Union, are named rubles, though they all are...

s ($3.85 billion), and resulted in a series of eleven separate dams measuring 25 kilometres (15.5 mi) across the Gulf of Finland
Gulf of Finland
The Gulf of Finland is the easternmost arm of the Baltic Sea. It extends between Finland and Estonia all the way to Saint Petersburg in Russia, where the river Neva drains into it. Other major cities around the gulf include Helsinki and Tallinn...

. Built into the structure are two openings to allow ships to pass through, six gates that can be closed to hold back water, and about 30 facilities for purifying water flowing into the gulf. It took 42 hm³ (54,933,926 cu yd) of stone and soil, 2 hm³ (2,615,901.2 cu yd) of reinforced concrete and about 100000 tonne of steel structures and other materials to build the dam. The project was designed and implemented by over 100 scientific and design institutions, construction companies and suppliers of materials and equipment.

Criticism

Environmentalists have raised concerns and staged demonstrations during construction of the dam. The main concerns relate to water quality and impact on historically significant sites. Due to protests and financial problems, the dam is regarded as one of the most notorious legacy construction projects from the former Soviet Union.

Water quality

Untreated wastewater from Saint Petersburg is the Baltic’s single biggest pollution point source. Environmentalists fear that the dam will constrain water flow, accumulating polluted water inside the dam. Damming an estuary and altering its flow pattern generates a number of physical and biological impacts; the disruption of the normal flow obstructs natural current and affects the water’s habitat. The 60 canals and rivers that flow through Saint Petersburg will all discharge into the dammed area. Beaches in this area are already seriously polluted. Only the Neva’s water is currently good enough to serve as a source for drinking water. Activists remain concerned the dam will transform the mouth of the Neva into "a cesspool of unpurified sewage" and endanger the water supply. At the same time, water quality in the Baltic beyond the dam has improved.

To address the problem of water pollution, the city's government adopted a plan to upgrade the city's sewage system to limit the amount of untreated wastewater release to less than 0.1%. The measures being taken seem to be quite efficient – after the launch of modern long-awaited South-West Wastewater Treatment Plant in 2006 the amount of biological and phosphate waste is expected to be lowered by 60% and 25%, respectively.

Over 30 water purification installations are placed around the complex, a part of a larger effort to clean the water in the Neva Bay.

World Heritage Site impacts

The dam passes through the historic Northern Forts of Kronstadt, which is a World Heritage Site
World Heritage Site
A UNESCO World Heritage Site is a place that is listed by the UNESCO as of special cultural or physical significance...

.

External links

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