Katrina Ann Hodgkinson is Federal Vice President of the National Party of Australia and a former Australian Member of Parliament. She was a member of the New South Wales Legislative Assembly, representing Cootamundra for The Nationals from 28 March 2015 to 1 September 2017, Burrinjuck from 27 March 1999 to 27 March 2015. Hodgkinson was educated at Canberra Girls' Grammar School and Narrabundah College, Metropolitan Business College of New South Wales, she was an Executive Officer in the Commonwealth Department of Transport and for Sydney property development companies, becoming Secretary of the Year for the North Sydney region in 1989. She was a Technical and Further Education instructor from 1989 to 1991, owned regional small businesses from 1989 to 1997 and she was Adviser to Senator the Hon Nick Minchin, Special Minister of State and Minister for Industry and Resources from 1997 to 1999. In 1995, Hodgkinson sought election to the seat of Southern Highlands in a three-cornered-contest. Despite receiving the highest primary vote, The Nationals were defeated on preferences.
In 1998 Alby Schultz Member for Burrinjuck, resigned from NSW Parliament to contest the seat of Hume. Hodgkinson was elected to NSW Parliament at the subsequent 1999 election. Between 2003 and 2011 Hodgkinson held a range of shadow ministerial responsibilities including Fair Trading and Small Business, Major Events, Community Services and Child Safety, Rural Affairs, Natural Resource Management. In 2007, a substantial redistribution of electorate boundaries saw her constituency base move from Goulburn and Tumut to Cowra, Cootamundra and Young. Following the 2011 state election, Hodgkinson was appointed on 3 April 2011 as NSW's first female Minister for Primary Industries and as Minister for Small Business. In 2013 a further statewide electoral redistribution was announced by the NSW Electoral Commission that resulted in a substantial revision of Hodgkinson's seat of Burrinjuck, including the loss of her home town of Yass, the seat renamed Cootamundra, with effect from the 2015 NSW State election.
At the same time, the neigbouring seat of electoral district of Goulburn, held by Minister for Community Services Pru Goward, was pushed westward to take in portions of Hodgkinson's former territory, including Hodgkinson's hometown of Yass and her current home in Berrima. Hodgkinson announced plans to seek Nationals preselection in Goulburn, claiming that the redrawn Cootamundra was too far away from her base; this touched off a dispute between the Liberals and Nationals, as it would have breached a longstanding Coalition agreement not to run three-cornered contests. Hodgkinson dropped plans to challenge Goward and contested Cootamundra, which she won easily. Due to the resignation of Barry O'Farrell as Premier and Deputy Premier Andrew Stoner in 2014 and the subsequent ministerial reshuffle by new Premier Mike Baird and new Deputy Premier and Minister for Racing Troy Grant, in addition to her existing responsibilities as Minister for Primary Industries, Hodgkinson was appointed Assistant Minister for Tourism and Major Events Hodgkinson was appointed NSW's first Parliamentary Secretary for Southern NSW in the second Baird ministry following the 2015 state election.
Following the introduction by the Baird-Grant Government in October 2016 of legislation to ban greyhound racing in NSW, with fellow Nationals MPs for the seats of Barwon and Clarence, crossed the floor to vote against the ban. After months of intense public pressure from regional communities, Premier Baird introduced new legislation overturning the greyhound racing ban that he and Grant had introduced, retired from State Parliament. Hodgkinson graduated from the Australian Institute of Company Directors in 2015, as a Master of Business Administration through the Australian Institute of Business in 2017. On 31 July 2017, she announced her intention to retire from the NSW Parliament effective 1 September 2017, resulting in a by-election for the seat of Cootamundra. Hodgkinson was elected Federal Vice President of the National Party of Australia in August 2018. In 2019 she makes a tilt at federal politics as she became the National candidate for the seat of Gilmore at the 2019 election
Goulburn, New South Wales
Goulburn is a regional city in the Southern Tablelands of New South Wales, Australia 195 kilometres south-west of Sydney, 90 kilometres north-east of Canberra. It was proclaimed as Australia's first inland city through letters patent by Queen Victoria in 1863. Goulburn had a population of 22,890 at the 2016 census. Goulburn is the seat of Goulburn Mulwaree Council. Goulburn is a railhead on the Main Southern line, a service centre for the surrounding pastoral industry, stopover for those travelling on the Hume Highway, it has many historic buildings. It is home to the monument the Big Merino, a sculpture, the world's largest concrete constructed sheep. Goulburn was named by surveyor James Meehan after Henry Goulburn, Under-Secretary for War and the Colonies, the name was ratified by Governor Lachlan Macquarie; the Mulwaree People are the original people of the land they belonged to the Ngunawal and Gandangara language groups, a Murring/Wiradjuri word indicating a special Indigenous cultural area.
The colonial government made land grants to free settlers such as Hamilton Hume in the Goulburn area from the opening of the area to settlement in about 1820. Land was sold to settlers within the Nineteen Counties, including Argyle County; the process displaced the local indigenous Mulwaree population and the introduction of exotic livestock drove out a large part of the Aboriginal peoples' food supply. The Mulwaree People lived throughout the area covering Goulburn and Yass. and belong to the Ngunawal language group. To the north of Goulburn Gundungurra was spoken within the lands of the Dharawal People; this was due to Gundungurra people of the Blue Mountains being driven south from their traditional land due to Governor Macquarie's parties sent to massacre the Dharawal and Gundungurra People. Their neighbours were the Dharawal to their north and Dharug surrounding Sydney, Wiradjuri Ngunawal and Thurrawal, peoples; the reduction of the food supply and the introduction of exotic diseases reduced the local indigenous population.
Some local Aborigines survived at the Tawonga Billabong Aboriginal Settlement established under the supervision of the Tarago police. In the 1930s the local billabong dried up and the Aboriginal people moved away although some have, over time, made their way back to their traditional lands; the first recorded settler in Goulburn established'Strathallan' in 1825 and a town was surveyed in 1828, although moved to the present site of the city in 1833 when the surveyor Robert Hoddle laid it out. George Johnson purchased the first land in the area between 1839 and 1842 and became a central figure in the town's development, he established a branch store with a liquor licence in 1848. The 1841 census records Goulburn had a population of 444 males and 211 females; this number had jumped to 1171 inhabitants by 686 males and 485 females. It had a courthouse, police barracks, churches and post office and was the centre of a great sheep and farming area. A telegraph station opened in 1862, by which time there were about 1,500 residents, a blacksmith's shop, two hotels, two stores, the telegraph office and a few cottages.
The town was a change station for Cobb & Co by 1855. A police station opened the following year and a school in 1858. Goulburn was proclaimed a municipal government in 1859 and was made a city in 1863. Goulburn holds the unique distinction of being proclaimed a City on two occasions; the first, proclamation was claimed by virtue of Royal Letters Patent issued by Queen Victoria on 14 March 1863 to establish the Diocese of Goulburn. It was a claim made for ecclesiastical purposes, as it was required by the traditions of the Church of England; the Letters Patent established St Saviour's Church as the Cathedral Church of the diocese. This was the last instance in which Letters Patent were used in this manner in the British Empire, as they had been discredited for use in the colonies, were soon to be declared formally invalid and unenforceable in this context. Several legal cases over the preceding decade in particular had established that the monarch had no ecclesiastical jurisdiction in colonies possessing responsible government.
This had been granted to NSW in 1856, seven years earlier. The Letters Patent held authority only over those who submitted to it voluntarily, only within the context of the Church – it had no legal civil authority or implications. An absolute and retrospective declaration to this effect was made in 1865 in the Colenso Case, by the Judiciary Committee of the Privy Council. However, under the authority of the Crown Lands Act 1884, Goulburn was proclaimed a City on 20 March 1885 removing any lingering doubts as to its status; this unrecognised controversy has in no way hindered the development of Goulburn as a regional centre, with an impressive court house and other public buildings, as a centre for wool selling, as an industrial town. The arrival of the railway in 1869, opened on 27 May by the Governor Lord Belmore, along with the completion of the line from Sydney to Albury in 1883, was a boon to the city. Branchlines were constructed to Cooma and extended further to Nimmitabel and to Bombala, to Crookwell and Taralga.
Goulburn became a major railway centre with a roundhouse and engine servicing facilities and a factory which made pre-fabricated concrete components for signal boxes and station buildings. The roundhouse is now the
ABC Radio National, known on-air as RN, is an Australia-wide Public Service Broadcasting radio network run by the Australian Broadcasting Corporation. Radio National broadcasts national programming in subjects that include news and current affairs, the arts, social issues, science and comedy; some programs are relayed on Radio Australia, the ABC's international international broadcasting service, transmitted on shortwave until January 2017. Radio National has 327 transmitter sites and covers over 98% of the permanently inhabited areas of Australia. Remote areas are served by satellite service. All radio programs are available for live streaming over the Internet, most as audio-on-demand, or for download as MP3s for at least four weeks after broadcast; some programs are available as MP3s going back to 2005. From 1928, the National Broadcasting Service, as part of the federal Postmaster-General's Department took over responsibility for all the existing stations that were sponsored by public licence fees.
The outsourced Australian Broadcasting Company supplied programs from 1929. In 1932 a commission was established, merging the original ABC company and the National Broadcasting Service, it is from this time that Radio National dates as a distinct network within the ABC, in which a system of program relays was developed during the subsequent decades to link stations spread across the nation. Radio National's Sydney station 2FC first test broadcast on 5 December 1923 and went to air on 9 January 1924. 2FC stood for the original owner of the station before the ABC took it over. The origins of the other stations in the network were: 3AR Melbourne – 26 January 1924 "Associated Radio Company of Australia", organized by Esmond Laurence Kiernan and others. 5CL Adelaide – 20 November 1924 "Central Broadcasters Ltd" 7ZL Hobart – 17 December 1924 4QG Brisbane – 27 July 1925 "Queensland Government" 6WN Perth – 5 October 1938 "Wanneroo" 2CY Canberra – 23 December 1938 2NA Newcastle – 20 December 1943The first transmitters for 2FC, 5CL and 4QG were made by AWA with power of 5 kW.
They used a MT7A valve for a MT7B for the modulator. The power supply was 12,000 volts from three phase power rectified by MR7 valves. Note that 4QG commenced with a 500 Watt transmitter which continued for about 6 months until the 5 kW unit was commissioned; the radio transmitters for 3AR and 2FC were upgraded to 10 kW in a contract let in 1938 to STC. The transmitters were designed by Charles Strong in London, were notable in using negative feedback to ensure a high quality flat frequency response. From 1947 until the mid-1980s, "Radio 2" was broadcast to the major metropolitan centres, with a large broadcast footprint in adjacent areas due to the powerful AM transmitters in use, it contained most of the ABC's national programming. The power level of 2FC and 3AR was upgraded to 50 kW in the early 1950s; the transmitters for these were housed in the same building as the radio 1 network. They were manufactured by STC; the final stage contained three parallel 3J/261E air cooled triodes running in class C amplifier at 90% efficiency.
These were driven by a class B push-pull modulator with the same type of valves. That of 5CL had to wait until late 1961. In the 1970s, the network's program format began to take on a more serious tone, a style which continues to this day. Art critic Peter Timm remarked that the network is "virtually the only non-print media forum for art in this country."In the early 1980s the broadcast footprint was extended with the construction of the first of over 300 regional FM transmitters. In 1985, the ABC renamed "Radio 2" as "Radio National". Since 1990, all Radio National stations have had the same callsign format, Radio National preceded by the appropriate number for the state or territory, sometimes followed by the locality; as a result of cuts in the 1996–97 budget, Radio National was hit with a reduction of a million dollars in its funding, with a significant impact on programming. In January 2012 Radio National was rebranded as RN in recognition of the stations growing digital audience. RN has been used as shorthand for the station's name by many presenters going back several years.
The stations tagline, which has changed over the years, was changed to "Your World Unfolding" to mesh with the station's new logo and visual identity. In January 2017 the schedule has been reduced in scope due to loss of staff and programmes; the times shown relate to Radio National's schedules in the eastern states of Australia. Pre-recorded shows are broadcast on time delay in the west. Full program guides for all regions are published on the RN website. AM, The World Today, PM: in-depth news and analysis Correspondents Report: in-depth news and analysis Asia Pacific: current regional affairs in the Asia Pacific region, from ABC Radio Australia Breakfast: "comprehensive coverage and analysis of national and international events - serious, fun and diverse" hosted by Fran Kelly RN Drive: "With fresh p
Goulburn Mulwaree Council
Goulburn Mulwaree Council is a local government area located in the Southern Tablelands region of New South Wales, Australia. The area is located adjacent to the Southern Highlands railway line; the estimated resident population of the area stood at 29,609 on 2016 census. The Mayor of Goulburn Mulwaree Council is Bob Kirk; the area covered under administration is 3,220 square kilometres and includes Goulburn and the towns and localities of: Parts of the Southern Highlands, the Southern Tablelands and Morton National Park lie within the Goulburn Mulwaree Council area. The council was formed as the Greater Argyle Council in 2004 as an amalgamation of Goulburn City and parts of the former Mulwaree Shire, it was renamed in 2005 following objections from the community. During 2011 - 2013, Goulburn Mulwaree Council has been at the centre of alleged breaches of NSW Council Rules and Regulations. In late 2013, a Government investigation by the New South Wales State Government found that the Goulburn Mulwaree Council’s Multi-Use Centre Tendering Process breached established State Regulations, ruling that: " Council contravened regulations, ignored tendering guidelines and offered unfair advantage to two tenderers including the successful tenderer, Bathurst firm, Hines Constructions."
The Investigation prompted multiple Council Internal Reform suggestions, as well as prompting the Council's General Manager Performance Review Committee to suspend the automatic employment renewal of Mr Chris Berry, the General Manager of Goulburn Mulwaree Council, in September 2013. In 2011, Goulburn Mulwaree Council partnered with Veolia Environmental Services in seed funding to make up $10,000 for an art award through the Goulburn Regional Art Gallery; the Award, known as the Veolia Environmental Services Art Award, prompted condemnation from the peak body for Australian visual and media arts, as well as an independent investigation after multiple complaints alleging the winning entry breached the stipulated entry conditions. The Investigation, completed by Planning and Economic Consulting, resulted in a 22-page report where: "The consultant recommended that Council make a public statement to acknowledge grievances and the necessary improvements. Secondly, gallery staff should be proactive in engaging professionals and judges to develop and benchmark the entry and judging criteria."
Veolia Environmental Services discontinued its annual $10,000 support for the Award in 2012. Goulburn Mulwaree Council is composed of nine Councillors elected proportionally as one entire ward. All Councillors are elected for a fixed four-year term of office; the Mayor is elected by the Councillors at the first meeting of the Council. The most recent election was held on 10 September 2016, the makeup of the Council is as follows: The current Council, elected in 2016, in order of election, is
Ryde Pumping Station
The Ryde Pumping Station is a heritage-listed pumping station and offices located at Victoria Road, West Ryde in the City of Ryde local government area of New South Wales, Australia. It was built from 1891 to 1921 by William Co. Ltd.. State Monier Works, Refshaw & O'Brien, it is known as Ryde Pumping Station and site, WP005 and West Ryde Pumping Station. The property is owned by an agency of the Government of New South Wales, it was added to the New South Wales State Heritage Register on 15 November 2002. The Ryde area was suitable for farming and orchards, early grants to marines were given to encourage agriculture. In 1792 land in the area was granted to eight marines. Isaac Archer and John Colethread each received 32 hectares of land on the site of the present Ryde-Parramatta Golf Links, now in West Ryde. In 1792, in the Eastern Farms area, twelve grants, most of them about 12 hectares, were made to convicts. Much these farms were bought by John Macarthur, Gregory Blaxland and the Reverend Samuel Marsden.
The district remained an important orchard area throughout the 19th century. The first pumping station at Ryde was built by the Harbours and Rivers Department, handed over to the newly formed Metropolitan Board of Water Supply and Sewerage in 1891. Water was delivered from Potts Hill Reservoir to a balance reservoir at West Ryde railway station. From here a pair of 146-horsepower vertical, direct-acting, surface-condensing pumping engines, lifted 3,400 gal/min of water to Ryde tank and Chatswood, to supply Sydney's northern distribution system. By 1916 the need to further increase pumping capacity could no longer be accommodated in the existing station. Land on the eastern boundary of the old station was acquired, a second much larger pumping station built; the new station was commissioned on the 15th September. The new station took over the pumping duties of the old until the old pumping station ceased to operate during November 1930; the old station was used as a store until it was demolished in 1961.
The new pumping station went through continual upgrades and amplifications to raise its pumping capacity from 20 megalitres per day in 1921, to 66 megalitres per day in 1956, to 90 megalitres per day in 1973, to 590 megalitres per day in 1982. In 1921 the station was pumping to Chatswood, Wahroonga, Mobbs Hill and Beecroft Reservoirs - thus to most of the North Shore. By 1982 the conversion to electrification was completed. With 13 pumping units installed and another on standby, the capacity of the station after electrification stood at 700 megalitres per day; the combination of electrification over steam, more powerful prime movers and improved suction mains, rising mains and manifolds, resulted in the great increase in capacity at the new station. This led to Ryde becoming the largest domestic water pumping station in Australia at that time. Turpentine-Ironbark forest on Wianamatta shale was the main vegetation type for much of the Ryde area. A typical sample is that within the small reserve at Twin Road and includes Turpentine and Grey Gum.
During the 19th century much of the Ryde area was cleared for its timber and to provide land for farming while the post-WW II suburban expansion resulted in the further loss of extensive remnant areas of bushland. More recent treatment of the grounds reflects an attempt to soften the impact of the introduction of the many office buildings and demountables associated with the use of the place by Sydney Water and, until June 2001, Australian Water Technologies; the Ryde Pumping Station is located in West Ryde, on an irregular shaped block of land bounded by Victoria Road to the north, by Hermitage Road to the south east and by the Strathfield to Hornsby railway line to the west. While the Ryde site continues to be used for water pumping purposes, it houses the offices of AWT ES & T in a mosaic of permanent and temporary buildings dating from the late 20th Century; the pumping station building which fronts Victoria Road comprises a small Administration Block, the Engine House and the adjoining Boiler House and Economiser House.
There is a reinforced concrete viaduct or coal staith at the south end, which allowed railway coal wagons to be transported to the top of the building and emptied over the coal bunkers inside. Under the Engine and Boiler Houses there are basements and a sub-basement is located under the Engine Room which houses the turbine condensers and auxiliary pumps; the Boiler House occupies the central section of the Pumping Station and is much higher than the flanking Engines and Economiser Houses, the cladding on the main roof and the monitor is the original fibro tiles. The Boiler House still contains its rail lines and coal bunkers at roof level, but the boilers have been removed; the Economiser House is on the west side of the building adjoining the Boiler House but much lower. Its roof structure and length is the same as the Boiler House. Although it is now empty it contained the economisers, induced draught fans and the feed pumps and feed water heater for the boilers; the south side of the Boiler House is joined by the Coal Staith, a reinforced concrete viaduct which carries a pair of rail sidings for the coal wagons from the high embankment to the coal bunker doors.
Original reservoir valve house: A red brick and stone Queen Anne revival valve enclosure, located on the western side of the original reservoir. The valve house enclosure is missing its original door case
Trout is the common name for a number of species of freshwater fish belonging to the genera Oncorhynchus and Salvelinus, all of the subfamily Salmoninae of the family Salmonidae. The word trout is used as part of the name of some non-salmonid fish such as Cynoscion nebulosus, the spotted seatrout or speckled trout. Trout are related to salmon and char: species termed salmon and char occur in the same genera as do fish called trout. Lake trout and most other trout live in freshwater lakes and rivers while there are others, such as the steelhead, which can spend two or three years at sea before returning to fresh water to spawn. Steelhead that live out their lives in fresh water are called rainbow trout. Arctic char and brook trout are part of the char family. Trout are an important food source for humans and wildlife, including brown bears, birds of prey such as eagles, other animals, they are classified as oily fish. The name'trout' is used for some species in three of the seven genera in the subfamily Salmoninae: Salmo, Atlantic species.
Fish referred to as trout include: Genus Salmo Adriatic trout, Salmo obtusirostris Brown trout, Salmo trutta River trout, S. t. morpha fario Lake trout/Lacustrine trout, S. t. morpha lacustris Sea trout, S. t. morpha trutta Flathead trout, Salmo platycephalus Marble trout, Soca River trout or Soča trout – Salmo marmoratus Ohrid trout, Salmo letnica, S. balcanicus, S. lumi, S. aphelios Sevan trout, Salmo ischchan Genus Oncorhynchus Biwa trout, Oncorhynchus masou rhodurus Cutthroat trout, Oncorhynchus clarki Coastal cutthroat trout, O. c. clarki Crescenti trout, O. c. c. f. crescenti Alvord cutthroat trout O. c. alvordensis Bonneville cutthroat trout O. c. utah Humboldt cutthroat trout O. c. humboldtensis Lahontan cutthroat trout O. c. henshawi Whitehorse Basin cutthroat trout Paiute cutthroat trout O. c. seleniris Snake River fine-spotted cutthroat trout, O. c. behnkei Westslope cutthroat trout O. c. lewisi Yellowfin cutthroat trout O. c. macdonaldi Yellowstone cutthroat trout O. c. bouvieri Colorado River cutthroat trout O. c. pleuriticus Greenback cutthroat trout O. c. stomias Rio Grande cutthroat trout O. c. virginalis Oncorhynchus gilae Gila trout, O. g. gilae Apache trout, O. g. apache Rainbow trout, Oncorhynchus mykiss Kamchatkan rainbow trout, Oncorhynchus mykiss mykiss Columbia River redband trout, Oncorhynchus mykiss gairdneri Coastal rainbow trout, Oncorhynchus mykiss irideus Beardslee trout, Oncorhynchus mykiss irideus var. beardsleei Great Basin redband trout, Oncorhynchus mykiss newberrii Golden trout, Oncorhynchus mykiss aguabonita Kern River rainbow trout, Oncorhynchus mykiss aguabonita var. gilberti Sacramento golden trout, Oncorhynchus mykiss aguabonita var. stonei Little Kern golden trout, Oncorhynchus mykiss aguabonita var. whitei Kamloops rainbow trout, Oncorhynchus mykiss kamloops Baja California rainbow trout, Nelson's trout, or San Pedro Martir trout, Oncorhynchus mykiss nelsoni Eagle Lake trout, Oncorhynchus mykiss aquilarum McCloud River redband trout, Oncorhynchus mykiss stonei Sheepheaven Creek redband trout Mexican golden trout, Oncorhynchus chrysogaster Genus Salvelinus Brook trout, Salvelinus fontinalis Aurora trout, S. f. timagamiensis Bull trout, Salvelinus confluentus Dolly Varden trout, Salvelinus malma Lake trout, Salvelinus namaycush Silver trout, † Salvelinus agassizi Hybrids Tiger trout, Salmo trutta X Salvelinus fontinalis Speckled Lake trout, Salvelinus namaycush X Salvelinus fontinalis Trout that live in different environments can have different colorations and patterns.
These colors and patterns form as camouflage, based on the surroundings, will change as the fish moves to different habitats. Trout in, or newly returned from the sea, can look silvery, while the same fish living in a small stream or in an alpine lake could have pronounced markings and more vivid coloration. In general trout that are about to breed have intense coloration, they can look like an different fish outside of spawning season. It is impossible to define a particular color pattern as belonging to a specific breed. Trout have fins without spines, all of them have a small adipose fin along the back, near the tail; the pelvic fins sit well back on each side of the anus. The swim bladder is connected to the esophagus, allowing for gulping or rapid expulsion of air, a condition known as physostome. Unlike many other physostome fish, trout do not use their bladder as an auxiliary device for oxygen uptake, relying on their gills. There are many species, more populations, that are isolated from each other and morphologically different.
However, since many of these distinct populations show no significant genetic differences, what may appear to be a large number of species is considered a much smaller number of distinct species by most ichthyologists. The trout found in the eastern United States are a good example of this; the brook trout, the aurora trout, the silver trout all have physical characteristics and colorations that distinguish them, yet genetic analysis shows that they are one species, Salvelinus fontinalis. Lake trout, like brook trout, belong to the char genus. Lake trout inhabit many of the larger lakes in North America, live m
An embankment dam is a large artificial dam. It is created by the placement and compaction of a complex semi-plastic mound of various compositions of soil, clay, or rock, it has a semi-pervious waterproof natural covering for a dense, impervious core. This makes such a dam impervious to 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. Embankment dams come in two types: the earth-filled dam made of compacted earth, the rock-filled dam. A cross-section of an embankment dam shows a shape like hill. Most have a central section or core composed of an impermeable material to stop water from seeping through the dam; the core can be of concrete, or asphalt concrete. This dam type is a good choice for sites with wide valleys, they can be built on softer soils. For a rock-fill dam, rock-fill is blasted using explosives to break the rock.
Additionally, the rock pieces may need to be crushed into smaller grades to get the right range of size for use in an embankment dam. The building of a dam and the filling of the reservoir behind it places a new weight on the floor and sides of a valley; the stress of the water increases linearly with its depth. Water pushes against the upstream face of the dam, a nonrigid structure that under stress behaves semiplastically, causes greater need for adjustment near the base of the dam than at shallower water levels, thus the stress level of the dam must be calculated in advance of building to ensure that its break level threshold is not exceeded. Overtopping or overflow of an embankment dam beyond its spillway capacity will cause its eventual failure; the erosion of the dam's material by overtopping runoff will remove masses of material whose weight holds the dam in place and against the hydraulic forces acting to move the dam. A small sustained overtopping flow can remove thousands of tons of overburden soil from the mass of the dam within hours.
The removal of this mass unbalances the forces that stabilize the dam against its reservoir as the mass of water still impounded behind the dam presses against the lightened mass of the embankment, made lighter by surface erosion. As the mass of the dam erodes, the force exerted by the reservoir begins to move the entire structure; the embankment, having no elastic strength, would begin to break into separate pieces, allowing the impounded reservoir water to flow between them and removing more material as it passes through. In the final stages of failure the remaining pieces of the embankment would offer no resistance to the flow of the water and continue to fracture into smaller and smaller sections of earth or rock until these would disintegrate into a thick mud soup of earth and water. Therefore, safety requirements for the spillway are high, require it to be capable of containing a maximum flood stage, it is common for its specifications to be written such. A number of embankment dam overtopping protection systems have been developed.
These techniques include the concrete overtopping protection systems, timber cribs, sheet-piles and gabions, reinforced earth, minimum energy loss weirs, embankment overflow stepped spillways and the precast concrete block protection systems. Earth structure Gravity dam List of largest dams in the world Embankment dams Table of contents An introduction to embankment dams 100 Years of Embankment Dam Design and Construction in the U. S. Bureau of Reclamation