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, aquaculture, and navigability. Hydropower is often used in conjunction with dams to generate electricity. A dam can also be used to collect or store water which can be evenly distributed between locations. 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. The earliest known dam is the Jawa Dam in Jordan, dating to 3,000 BC.
Hydroelectricity, or hydroelectric power, is electricity produced from hydropower. In 2020 hydropower generated one sixth of the world's electricity, almost 4500 TWh, which was more than all other renewables combined and also more than nuclear power.
Waterfall is a small suburb in southern Sydney, in the state of New South Wales, Australia. It is 40 kilometres south of the Sydney central business district in the Sutherland Shire. It is the southernmost suburb of Sydney in the eastern corridor, bordering the Illawarra region.
A reservoir is most commonly an enlarged natural or artificial lake created using a dam to store fresh water.
The San Luis Reservoir is an artificial lake on San Luis Creek in the eastern slopes of the Diablo Range of Merced County, California, approximately 12 mi (19 km) west of Los Banos on State Route 152, which crosses Pacheco Pass and runs along its north shore. It is the fifth largest reservoir in California. The reservoir stores water taken from the San Joaquin-Sacramento River Delta. Water is pumped uphill into the reservoir from the O'Neill Forebay which is fed by the California Aqueduct and is released back into the forebay to continue downstream along the aqueduct as needed for farm irrigation and other uses. Depending on water levels, the reservoir is approximately nine miles long from north to south at its longest point, and five miles (8 km) wide. At the eastern end of the reservoir is the San Luis Dam, or the B.F. Sisk Dam, the fourth largest embankment dam in the United States, which allows for a total capacity of 2,041,000 acre-feet (2,518,000 dam3). Pacheco State Park lies along its western shores.
The Woronora Dam is a heritage-listed concrete gravity dam with an uncontrolled serpentine spillway across the Woronora River, located south of Greater Metropolitan Sydney, in the suburb of Woronora Dam, Sutherland Shire, New South Wales, Australia. The principal purpose of the dam is for potable water supply for Sydney's southern suburbs and the northern suburbs of the Illawarra region. The impounded 71,790-megalitre reservoir is also called Woronora Dam and is sometimes incorrectly called Lake Woronora. The dam was designed by G. E. Haskins, Chief Engineer and the Metropolitan Water, Sewerage and Drainage Board of NSW (MWS&DB) and built from 1927 to 1941 by the MWS&DB. The property is owned by the Sydney Catchment Authority, an agency of the Government of New South Wales. It was added to the New South Wales State Heritage Register on 18 November 1999.
Helensburgh is a small town in New South Wales, Australia. Helensburgh is located 45 kilometres south of the Sydney central business district and 35 kilometres (22 mi) north of Wollongong. Helensburgh is in the local government area of Wollongong City Council and marks the northern end of the Illawarra region. It is approximately halfway between Sydney and Wollongong, at the southern end of the Royal National Park.
Malampuzha Dam is the largest dam and reservoirs in Kerala, located near Palakkad, in the state of Kerala in South India, built post independence by the then Madras state. Situated in the scenic hills of the Western Ghats in the background it is a combination of a masonry dam with a length of 1,849 metres and an earthen dam with a length of 220 metres making it the longest dam in the state. The dam is 355 feet high and crosses the Malampuzha River, a tributary of Bharathappuzha, Kerala's second longest river. There is a network of two canal systems that serve the dam's reservoir of 42,090 hectares.
Run-of-river hydroelectricity (ROR) or run-of-the-river hydroelectricity is a type of hydroelectric generation plant whereby little or no water storage is provided. Run-of-the-river power plants may have no water storage at all or a limited amount of storage, in which case the storage reservoir is referred to as pondage. A plant without pondage is subject to seasonal river flows, thus the plant will operate as an intermittent energy source. Conventional hydro uses reservoirs, which regulate water for flood control, dispatchable electrical power, and the provision of fresh water for agriculture.
An embankment dam is a large artificial dam. It is typically created by the placement and compaction of a complex semi-plastic mound of various compositions of soil or rock. It has a semi-pervious waterproof natural covering for its surface and a dense, impervious core. This makes the dam impervious to surface or seepage erosion. Such a dam is composed of fragmented independent material particles. The friction and interaction of particles binds the particles together into a stable mass rather than by the use of a cementing substance.
Aliyar (ஆழியாறு) (also spelt Azhiyar / Aaliyar) Reservoir is a 6.48 km2 (2.5 sq mi) reservoir located in Aliyar village near Pollachi town in Coimbatore District, Tamil Nadu, South India. The dam is located in the foothills of Valparai, in the Anaimalai Hills of the Western Ghats. It is about 65 kilometres (40 mi) from Coimbatore. The dam offers some ideal getaways including a park, garden, aquarium, play area and a mini Theme-Park maintained by Tamil Nadu Fisheries Corporation for visitors enjoyment. The scenery is beautiful, with mountains surrounding three quarters of the reservoir. Boating is also available.
Sholayar Dam is a concrete dam built across the Chalakkudi River in Malakkappara, Thrissur district, Kerala state of India. The dam consists of main Sholayar Dam, Sholayar Flanking and Sholayar Saddle Dam. It also contains Sholayar Hydro Electric Power Project of Kerala State Electricity Board who owns the dam. Total installed capacity of the project is 54MW with 3 penstock pipes. The maximum storage capacity is 2663 feet. Sholayar is 65 km from Chalakudy town. The dam above Sholayar dam was Upper Solaiyar Dam owned by Tamilnadu.
Helensburgh is a suburb of the New Zealand city of Dunedin. It is located to the northwest of the city centre.
Saville Dam is an earthen embankment dam with masonry work on the eastern branch of the Farmington River in southwestern Barkhamsted, Connecticut. The dam is 135 ft. tall and 1,950 ft. long and has an uncontrolled spillway on its western portion. It creates the Barkhamsted Reservoir which has a volume of 36.8 billion US gallons (139,000,000 m3) and is the primary water source for Hartford, Connecticut.
National grid reference NS27609150
The reservoir is of the non-impounding variety. It is no longer part of the local water supply system and is used by Helensburgh Angling Club. The earthen dam is 9 metres high and records show it was constructed before 1875.
