A drought is a period of drier-than-normal conditions. A drought can last for days, months or years. Drought often has large impacts on the ecosystems and agriculture of affected regions, and causes harm to the local economy. Annual dry seasons in the tropics significantly increase the chances of a drought developing and subsequent wildfires. Periods of heat can significantly worsen drought conditions by hastening evaporation of water vapour.
Lake Travis is a reservoir on the Colorado River in central Texas in the United States.
Lake Mead is a reservoir formed by Hoover Dam on the Colorado River in the Southwestern United States. It is located in the states of Nevada and Arizona, 24 mi (39 km) east of Las Vegas. It is the largest reservoir in the US in terms of water capacity. Lake Mead provides water to the states of Arizona, California, and Nevada as well as some of Mexico, providing sustenance to nearly 20 million people and large areas of farmland.
Warragamba Dam is a heritage-listed dam in the outer South Western Sydney suburb of Warragamba, Wollondilly Shire in New South Wales, Australia. It is a concrete gravity dam, which creates Lake Burragorang, the primary reservoir for water supply for the city of Sydney. The dam wall is located approximately 65 kilometres (40 mi) W of Sydney central business district, 4½ km SW of the town of Wallacia, and 1 km NW of the village of Warragamba.
Lake Burragorang is a man-made reservoir in the lower Blue Mountains of New South Wales, Australia, serving as a major water supply for greater metropolitan Sydney. The dam impounding the lake, the Warragamba Dam, is located approximately 60 kilometres (37 mi) southwest of the Sydney central business district.
Cachuma Lake is a reservoir in the Santa Ynez Valley of central Santa Barbara County, California on the Santa Ynez River adjoining the north side of California State Route 154. The artificial lake was created by the construction of Bradbury Dam, a 201 ft (61 m) earth-fill structure built by the U.S. Bureau of Reclamation in 1953. Its surface area covers 3,100 acres (1,300 ha), with a maximum design capacity of 205,000 acre⋅ft (253,000,000 m3), but it is currently limited to 188,000 acre⋅ft (232,000,000 m3) due to sediment accumulation. The late-December 2022 and early-January 2023 storms dramatically raised the water level in the lake, from an average of 33% full to 100% full for the first time in 12 years.
The Ross Barnett Reservoir, often called the Rez, is a reservoir of the Pearl River between Madison and Rankin counties in the U.S. state of Mississippi. The 33,000-acre (130 km2) lake serves as the state's largest drinking water resource, and is managed by the Pearl River Valley Water Supply District. The lake features 105 miles (169 km) of shoreline impounded on the south by a 3.5-mile (5.6 km) man-made dam and spillway. The western shore is bounded by the historic Natchez Trace Parkway.
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.
Lake Lanier is a reservoir in the northern portion of the U.S. state of Georgia. It was created by the completion of Buford Dam on the Chattahoochee River in 1956, and is also fed by the waters of the Chestatee River. The lake encompasses 38,000 acres (150 km2) or 59 sq mi (150 km2) of water, and 692 mi (1,114 km) of shoreline at normal level, a "full pool" of 1,071 ft (326 m) above mean sea level and the exact shoreline varies by resolution according to the coastline paradox. Named for poet Sidney Lanier, it was built and is operated by the U.S. Army Corps of Engineers for flood control and water supplies. Its construction destroyed more than 50,000 acres (20,000 ha) of farmland and displaced more than 250 families, 15 businesses, and relocated 20 cemeteries along with their corpses in the process.
Burrendong Dam is a rock-fill embankment major gated dam with a clay core across the Macquarie River upstream of Wellington in the central west region of New South Wales, Australia. The dam's purpose includes flood mitigation, irrigation, water supply and hydro-electric power generation. The dam impounds Lake Burrendong and is filled by the waters from the Macquarie, and Cudgegong rivers as well as Meroo Creek.
The Wivenhoe Dam is a rock and earth-fill embankment dam with a concrete spillway across the Brisbane River in South East Queensland, Australia. The dam takes it names from the local Wivenhoe Pocket rural community. The dam wall is located about 80 kilometres (50 mi) by road from the centre of Brisbane. The primary purpose of the dam is the supply of potable water for the Brisbane and Ipswich regions. The dam also provides for flood mitigation control, hydroelectricity, and recreation. The impounded reservoir is called Lake Wivenhoe and the dam, the lake and a narrow strip of surrounding land forms a locality also called Lake Wivenhoe.
Hartwell Dam is a concrete and embankment dam located on the Savannah River at the border of South Carolina and Georgia, creating Lake Hartwell. The dam was built by the U.S. Army Corps of Engineers between 1955 and 1962 for the purposes of flood control, hydropower and navigation. The concrete and earthen structure spans 15,840 feet (4,828 m). The concrete section is 1,900 feet (579 m) long and rises 204 feet (62 m) above the riverbed at its apex. The Hartwell Dam currently produces 468 million KWh of electricity annually, has prevented over $40 million in flood damage since completion and also provides recreation, water quality, water supply, along with fish and wildlife management.
Lake Mendocino is a large reservoir in Mendocino County, California, northeast of Ukiah. It covers 1,922 acres (7.78 km2) and was formed by the construction of Coyote Valley Dam in 1958. The lake and dam provide flood control, water conservation, hydroelectric power, and recreation. The dam also includes a fallout shelter built during the Cold War era to protect against the radiation from nuclear attacks from the Soviet Union.
Lake Livingston is a reservoir located in the East Texas Piney Woods. Lake Livingston was built and is owned and operated by the Trinity River Authority (TRA) of Texas under contract with the City of Houston for water-supply purposes. The USCG Auxiliary Flotilla 6-9 is also stationed on the lake. The lake is the third-largest lake located in the state of Texas. The Livingston Dam, constructed across the Trinity River about 7 miles (11 km) southwest of the city of Livingston is 2.5 miles (4 km) in length and has an average depth of 55 feet (17 m).
Terminus Dam is a dam on the Kaweah River in Tulare County, California in the United States, located near Three Rivers about 15 mi (24 km) from the western boundary of Sequoia National Park and 20 mi (32 km) east of Visalia. The dam forms Lake Kaweah for flood control and irrigation water supply. Completed by the U.S. Army Corps of Engineers (USACE) in 1962, Terminus is an earthfill dam 255 ft (78 m) high and 2,375 ft (724 m) long. The reservoir has a maximum capacity of 185,600 acre⋅ft (0.2289 km3) of water, although it usually sits at much lower levels.
Auburn Dam was a proposed concrete arch dam on the North Fork of the American River east of the town of Auburn, California, in the United States, on the border of Placer and El Dorado Counties. Slated to be completed in the 1970s by the U.S. Bureau of Reclamation, it would have been the tallest concrete dam in California and one of the tallest in the United States, at a height of 680 feet (210 m) and storing 2,300,000 acre-feet (2.8 km3) of water. Straddling a gorge downstream of the confluence of the North and Middle Forks of the American River and upstream of Folsom Lake, it would have regulated water flow and provided flood control in the American River basin as part of Reclamation's immense Central Valley Project.
Flood control methods are used to reduce or prevent the detrimental effects of flood waters. Flood relief methods are used to reduce the effects of flood waters or high water levels. Flooding can be caused by a mix of both natural processes, such as extreme weather upstream, and human changes to waterbodies and runoff. A distinction is made between structural and non-structural flood control measures. Structural methods physically restrain the flood waters, whereas non-structural methods do not. Building hard infrastructure to prevent flooding, such as flood walls, is effective at managing flooding. However, increased best practice within landscape engineering is to rely more on soft infrastructure and natural systems, such as marshes and flood plains, for handling the increase in water. To prevent or manage coastal flooding, coastal management practices have to handle natural processes like tides but also the human cased sea level rise.
The 2000s drought in Australia, also known as the millennium drought is said by some to be the worst drought recorded since European settlement.
The 2017 California floods affected parts of California in the first half of the year. Northern California saw its wettest winter in almost a century, breaking the record set in 1982–83. The same storm systems also flooded parts of western Nevada and southern Oregon. The damage was estimated at $1.55 billion ($1,850,488,732 today), including damage to California roads and highways estimated at more than $1.05 billion.
Heavy rainfall during the 2023 East Asian rainy season resulted in severe flooding and landslides across South Korea, primarily affecting residents in the provinces of North Chungcheong and North Gyeongsang. At least 47 people were killed and three are still missing as of July 22, 2023. The downpour is the heaviest in South Korea in 115 years.
