Hydraulic warfare (HW) is the use of water from reservoirs, rivers, canals, and other water features to impede the operations of an opposing force. This may involve breaching dams and rerouting watercourses. [1] It can be used to impede the advance of an attacker or to reduce the resources and tactical options for defenders. The technique has been used to create "devastating floods, isolate troops, cut off supply lines, hinder river crossings, and disrupt military timetables". [2]
Between the years 1500 and 2000, some 1/3 of floods in the Netherlands southwest were deliberately caused during wartime. The tactic was typically ineffective, and had damaged the land and local population. [1]
In 1938, China breached the dikes of the Yellow River to slow the advance of Japanese forces during the Second Sino-Japanese War. The flood became known as the largest such act in history. [1]
HW was used by Finland and the USSR during World War II. [1] British forces destroyed the Moehne and Edersee Dams in Western Germany to cut off the supply of water, power, river navigation, and flood protection to the Nazi regime. The breach of the Moehne dam unleashed a flood of 310,000 cfs, costing 1,200 lives. Bridges were washed out for 30 miles below the dam, and two power plants were submerged. The destruction of the Edersse dam produced similar flows and damaged infrastructure all the way to the Mittelland canal. Navigation was also disrupted as no water was available to stabilize the level of water in the river. Germany struck again by flooding the Pontine marshes in Italy, slowing the advance of Allied forces. Germany also flooded the Ay and Ill rivers in France and the Rur river in Germany. [2]
German forces flooded the Liri, Garigliano, and Rapido Rivers in Italy in early 1944. The Garigliano flood disrupted a British crossing, with knock-on effects on the Battle of Monte Cassino. Conversely, the Germans dammed up the Rapido river below an attempted crossing, creating a quagmire and delaying the operation.
The term originated in the 1950s, with the US Army Corps of Engineers. [2]
In 2022 and 2023, the appearance of flooded areas indicated the use of HW during the Russian invasion of Ukraine. [1]
The Battle of Monte Cassino, also known as the Battle for Rome, was a series of four military assaults by the Allies against German forces in Italy during the Italian Campaign of World War II. The objective was to break through the Winter Line and facilitate an advance towards Rome.
The United States Army Corps of Engineers (USACE) is a direct reporting unit and engineer formation of the United States Army that has three primary mission areas: Engineer Regiment, military construction, and civil works. The day-to-day activities of the three mission areas are administered by a lieutenant general known as the chief of engineers/commanding general. The chief of engineers commands the Engineer Regiment, comprising combat engineer, rescue, construction, dive, and other specialty units, and answers directly to the Chief of Staff of the Army. Combat engineers, sometimes called sappers, form an integral part of the Army's combined arms team and are found in all Army service components: Regular Army, National Guard, and Army Reserve. Their duties are to breach obstacles; construct fighting positions, fixed/floating bridges, and obstacles and defensive positions; place and detonate explosives; conduct route clearance operations; emplace and detect landmines; and fight as provisional infantry when required. For the military construction mission, the chief of engineers is directed and supervised by the Assistant Secretary of the Army for installations, environment, and energy, whom the President appoints and the Senate confirms. Military construction relates to construction on military bases and worldwide installations.
A sapper, also called a combat engineer, is a combatant or soldier who performs a variety of military engineering duties, such as breaching fortifications, demolitions, bridge-building, laying or clearing minefields, preparing field defenses, and road and airfield construction and repair.
A combat engineer is a type of soldier who performs military engineering tasks in support of land forces combat operations. Combat engineers perform a variety of military engineering, tunnel and mine warfare tasks, as well as construction and demolition duties in and out of combat zones.
The 21st Army Group was a British headquarters formation formed during the Second World War. It controlled two field armies and other supporting units, consisting primarily of the British Second Army and the First Canadian Army. Established in London during July 1943, under the command of Supreme Headquarters Allied Expeditionary Force (SHAEF), it was assigned to Operation Overlord, the Western Allied invasion of Europe, and was an important Allied force in the European Theatre. At various times during its existence, the 21st Army Group had additional British, Canadian, American and Polish field armies or corps attached to it. The 21st Army Group operated in Northern France, Luxembourg, Belgium, the Netherlands and Germany from June 1944 until August 1945, when it was renamed the British Army of the Rhine (BAOR).
The Siegfried Line campaign was a phase in the Western European campaign of World War II, which involved actions near the German defensive Siegfried Line.
The Royal Military Canal is a canal running for 28 miles (45 km) between Seabrook near Folkestone and Cliff End near Hastings, following the old cliff line bordering Romney Marsh, which was constructed as a defence against the possible invasion of England during the Napoleonic Wars.
Lake Allatoona is a U.S. Army Corps of Engineers reservoir on the Etowah River in northwestern part of the State of Georgia. This reservoir is mostly in southeastern Bartow County and southwestern Cherokee County. A small portion is located in Cobb County near Acworth.
Floodgates, also called stop gates, are adjustable gates used to control water flow in flood barriers, reservoir, river, stream, or levee systems. They may be designed to set spillway crest heights in dams, to adjust flow rates in sluices and canals, or they may be designed to stop water flow entirely as part of a levee or storm surge system. Since most of these devices operate by controlling the water surface elevation being stored or routed, they are also known as crest gates. In the case of flood bypass systems, floodgates sometimes are also used to lower the water levels in a main river or canal channels by allowing more water to flow into a flood bypass or detention basin when the main river or canal is approaching a flood stage.
Though Hurricane Katrina did not deal the city of New Orleans a direct hit on August 29, 2005, the associated storm surge precipitated catastrophic failures of the levees and flood walls. The Mississippi River Gulf Outlet ("MR-GO") breached its levees in approximately 15 places. The major levee breaches in the city include the 17th Street Canal levee, the London Avenue Canal, and the wide, navigable Industrial Canal, which left approximately 80% of the city flooded.
Operation Veritable was the northern part of an Allied pincer movement that took place between 8 February and 11 March 1945 during the final stages of the Second World War. The operation was conducted by Field Marshal Bernard Montgomery's Anglo-Canadian 21st Army Group, primarily consisting of the First Canadian Army under Lieutenant-General Harry Crerar and the British XXX Corps under Lieutenant-general Brian Horrocks.
Operation Diadem, also referred to as the Fourth Battle of Monte Cassino or, in Canada, the Battle of the Liri Valley, was an offensive operation undertaken by the Allies of World War II in May 1944, as part of the Italian Campaign of World War II. Diadem was supported by air attacks called Operation Strangle. The opposing force was the German 10th Army.
Wilson Dam is a dam on the Tennessee River between Lauderdale and Colbert counties in Alabama. Completed in 1924 by the United States Army Corps of Engineers, it impounds Wilson Lake, and is one of nine Tennessee Valley Authority (TVA) dams on the Tennessee River. It was declared a National Historic Landmark on November 13, 1966, for its role as the first dam to come under the TVA's administration. The dam is named for Woodrow Wilson.
Kentucky Dam is a hydroelectric dam on the Tennessee River on the county line between Livingston and Marshall counties in the U.S. state of Kentucky. The dam is the lowermost of nine dams on the river owned and operated by the Tennessee Valley Authority, which built the dam in the late 1930s and early 1940s to improve navigation on the lower part of the river and reduce flooding on the lower Ohio and Mississippi rivers. It was a major project initiated during the New Deal of President Franklin D. Roosevelt's administration, to invest in infrastructure to benefit the country. The dam impounds the Kentucky Lake of 160,000 acres (65,000 ha), which is the largest of TVA's reservoirs and the largest artificial lake by area in the Eastern United States. It was designated as an National Historic Civil Engineering Landmark by the American Society of Civil Engineers in 1996 and listed on the National Register of Historic Places in 2017.
The Battle of Canal du Nord was part of the Hundred Days Offensive of the First World War by the Allies against German positions on the Western Front. The battle took place in the Nord-Pas-de-Calais region of France, along an incomplete portion of the Canal du Nord and on the outskirts of Cambrai between 27 September and 1 October 1918. To prevent the Germans from sending reinforcements against one attack, the assault along the Canal du Nord was part of a sequence of Allied attacks at along the Western Front. The attack began the day after the Meuse-Argonne Offensive commenced, a day before an offensive in Belgian Flanders and two days before the Battle of St. Quentin Canal.
Obstacles to troop movement represent either natural, human habitat originated, constructed, concealed obstacles, or obstructive impediments to movement of military troops and their vehicles, or to their visibility. By impeding strategic, operational or tactical manoeuvre, the obstacle represents an added barrier between opposing combat forces, and therefore prevent achievement of objectives and goals specified in the operational planning schedule. The constructed obstacles are used as an aid to defending a position or area as part of the general defensive plan of the commander. The obstacles that originate from the human habitat can be converted by troops into constructed obstacles by either performing additional construction, or executing demolitions to obstruct movement over the transport network, to create a choke point, or to deny traversing of an area to the enemy. The natural obstacles can be used defensively by securing a more difficult to breach defensive position by for example securing a flank on terrain that is deemed impossible to traverse, thus denying the enemy an ability to close into combat range of direct fire weapons.
The Portland District is one of the five districts within the Northwestern Division of the United States Army Corps of Engineers. The Portland District is made up of some 1,100 civilian and 6 military personnel.
The Battle of Rapido River was fought from 20 to 22 January 1944 during one of the Allies' many attempts to breach the Winter Line during the Italian Campaign of World War II. Despite its name, the battle occurred on the Gari River.
Operation Rugged was a military operation performed by the United Nations Command (UN) during the Korean War designed to advance the UN lines to positions north of the 38th Parallel designated the Kansas Line. The operation would be the first phase of the advance, being immediately succeeded by Operation Dauntless which would take the UN forces to the Wyoming Line 10 miles (16 km) to 20 miles (32 km) north of the 38th Parallel. The operation resulted in a UN victory.
