Design Process Of Eucumbene Dam: Conceptual Design Phase

This paper presents an analysis of current conceptual design processes for high-rise buildings. We synthesize a method to document and measure these processes and use it to analyze data from several case studies and a survey of leading architectural and engineering design firms. We describe current highrise conceptual design process in terms of: design team size, composition, and time investment; clarity of goal definition; number and range of design options generated; number and type of model-based analyses performed; and the criteria used for decision making.

We identify several potential weaknesses in current design processes including lack of clarity in goal definition and a low quantity of generated and analyzed options. We argue that potentially higher performing designs are being left unconsidered, and discuss the potential reasons and costs. 

Overview of Eucumbene Dam

This is an assessment paper that seeks to analyze the design process of the Eucumbene Dam by majorly focusing on the conceptual design phase of the Eucumbene Dam. The conceptual design of the Eucumbene Dam will basically consider the performance measurement, maintenance, functional analysis, system planning, feasibility study, system operation requirements, needs definition, and construction process.

Eucumbene Dam is the primary gated earth-fill embankment dam with a bucket spillway and overflow ski-jump with to perpendicular lift gates across River Eucumbene in New South Wales’ Snowy Mountains. The major reason for the design and construction of the Eucumbene Dam is for the purposes of hydroelectric power and also for the purposes of irrigation in the complex constructed in south-east Australia. 

The design and construction process of Eucumbene Dam began in 1956 and was later completed in 1958 making it the major dam within the region. This dam was rated as one of the seven engineering wonders in the current world in the every 1967. The scheme covers an area of 7, 780 km² with generators large enough to generate approximately 17% of the total energy requirement in southeastern Australia but generates only 5% due to the limited quantity of water available (Allan, 2010).

The major reason for the construction of the Eucumbene Dam was for the purpose of generation of hydro-electric power station across Eucumbene River which rises below Shaw Hill, in the northern section of the Kosciuszko National Park, about 10km north of Kiandra village. There was the need for the construction of a hydro-electric power generation station which will form part of the Snowy Mountains Hydro-electric Scheme which is composed of 16 huge other dams and 9 hydro-electric power stations connected by 80km of aqueducts and 145 km of tunnels. Eucumbene River flows normally southeast and south before emptying into Lake Eucumbene after passing over and through the walls of the dam (Association, 2010).

The river flows generally south before emptying into Lake Jindabyne. The design and construction of the Eucumbene Dan and other Snowy Mountains Hydro-electricity Scheme was managed by the Snowy Hydro Limited which is an electricity retailing and Generation Company in Australia that maintains, manages and owns the scheme. The other reason for the design and construction of the Eucumbene Dam apart from the electricity generation was for form an irrigation complex in south-east Australia with the water for irrigation being supplied by the Eucumbene Dam and other Snowy River tributaries to the Murrumbidgee and Murray Rivers irrigation area (Golzé, 2009).

Reasons for Design and Construction

The conceptual design of the Eucumbene Dam involves analyzing the early and high-level cycle activity of the dam by considering factors such as feasibility study, performance measurement, system operation requirement, functional analysis, system planning, construction process, maintenance, and feasibility study. The reservoir impounded on Eucumbene Dam is known as Lake Eucumbene and is the biggest storage lake in the Snowy Mountains Scheme (Guyer, 2018).

Feasibility Study

The construction of the Eucumbene Dam began in 1956 and was later completed in 1958 after which it became the primary dam situated about 1 km northeast of Eucumbene Cove locality. The design and construction of the dam were carried out by the Kaiser-Walsh-Perini-Raymond and Department of Public Works based on the engineering plans established by the Department of Public Works and the United States Bureau of Reclamation, under agreement from the Snowy Mountains Hydro-electric Authority. The Eucumbene Dam erection and flooded the initial township of Old Adaminaby, which was repositioned to Adaminaby in the 1950s, demanding about 800 individuals to be relocated (Hanna, 2012).

The inner core of the dam was made of impervious, compacted clay, while the outer wall of the Eucumbene Dam was constructed of rock. The earth fills the embankment dam wall composed of rockfill of height 116m and rockfill 6,735,000m³ of the earth. The dam's foundation is composed of closely jointed quartzite and siltstone with an overburden of slope-wash and decomposed rock of approximately 6.1m deep. A secondary embankment possessing 121,900m³ of fill across a lower saddle makes the left abutment of the walls of the dam. The area of the surface of Lake Eucumbene is 14,542 Ha and the area of the catchment is 683 km^{2 (IPC, 2010)}.

System Planning

Eucumbene Dam is a primary gated earth-fill embankment dam with a bucket spillway and overflow ski-jump with two perpendicular lift gates across River Eucumbene in the Mountains of Snowy in NSW. The Eucumbene dam is an enormous artificial dam which is normally constructed by the compaction and settlement of an intricate semi-plastic mound of numerous configurations of rock, clay, sand, and soil. This kind of a dam has a dense impervious core and a semi-pervious waterproof natural covering for its surface. This makes such a dam to be impervious to the seepage erosion or surface. The embankment dams can be categorized into two different categories, namely rock-filled or earth-filled dam (Jackson, 2011).

Eucumbene Dam is an earth-fill type of an embankment dam since it is made of compacted earth. The embankment dam’s cross section denotes a form like a hill or a bank with a core made of an impervious material to discontinue seeping of water from the dam. The core may be made of asphalt concrete, clay, and concrete. They should be constructed on softer soils or hard rock and .

Conceptual Design of Eucumbene Dam

the system planning begins by the use of explosives to break the rock into pieces, and they made by further crushed into smaller grades to attain the right size range for the dam foundation. A spillway is also another structure of the Eucumbene Dam used in the provision of the controlled release of flows from the dam into a downstream region, normally riverbed of the Eucumbene River (Jansen, 2012). The figure below shows the cross-section of a typical spillway:

The spillway ensures that the water does not overflow and destroy or damage the dam. The fuse plugs and floodgates are designed into spillways for the purposes of reservoir level and water flow regulation. Water usually flows over a spillway only during the seasons of the flood when the reservoir cannot hold the excess water getting into the reservoir over the quantity of water being used.

There are two diverse categories of the spillway, namely uncontrolled and controlled. In an uncontrolled spillway, there are no gates and when the water upsurges above the crest or lip of the spillway, it starts to be discharged from the reservoir. The rate of water discharge in the type of spillway is regulated specifically by the water depth above the spillway of the reservoir. In the controlled spillway, there are mechanical gates or structures that regulate the rate of flow which enables approximately the full height of the dam to be used for storage of water (Jansen, 2012).

Functional Analysis

The functional analysis of the Eucumbene Dam involved the analysis of the major components making up the dam such as the Eucumbene River, Eucumbene Dam, Reservoir, and Snowy Mountains Hydro-electric Power stations. The major supplier of water to the Eucumbene Dam is the Eucumbene River which normally flows southeast and south before emptying into Lake Eucumbene after passing over and through the walls of the dam.

The river flows generally south before emptying into Lake Jindabyne (Thomas, 2010). The river descends 476m over 84km course joined by seven different minor tributaries. The flow of Eucumbene River is affected by the conditions of alpine with higher flows during spring seasons due to the melting if the snow. During the winter seasons, the river is subjected to ice and snow conditions (Leslie, 2013).

            Embankment dam is also another component designed during the design process of the entire system. The design and construction of the dam were carried out by the Kaiser-Walsh-Perini-Raymond and Department of Public Works based on the engineering plans established by the Department of Public Works and the United States Bureau of Reclamation, under agreement from the Snowy Mountains Hydro-electric Authority. The total capacity of the reservoir is 4798 GL with an active capacity of 4366.5 GL. The total catchment area of 683 km² and surface area of 14542 ha and maximum water depth of 107m (Martin, 2014).

Feasibility Study

The reservoir of the Embankment dam is the Lake Eucumbene which is the biggest reservoir in the Snowy Mountains Scheme and is the dominant link for the southern Snowy River and northern Tumut River. The Eucumbene River at Lake Eucumbene is joined to the Snowy River at the Bend Pondage Island. Snowy Hydro-electric power station is composed of 16 huge dams and connected by 80km of aqueducts and 154km of tunnels. This scheme is maintained, managed, and owned by the Snowy Hydro Limited which is a retailing and generating company. The scheme was completed while being supervised by Sir William Hudson who was the Chief Engineer (Pedro, 2009).

Performance Measurement

The current performance of the Eucumbene Dam can be evaluated by the capacity of the dam, spillways, reservoir, and hydro-electric power generation. Currently, the Eucumbene Dam has a height of 116m, length of 579m, and an elevation crest of 1168m. The total volume of the dam is 6,735,00m³. The type of spillway used during the construction of the dam and also currently is the overflow bucket and ski-jump bucket with vertical lift gates. The capacity of the spillway is currently 475m³/s. The major supplier of water to the Eucumbene Dam is still the Eucumbene River which normally flows southeast and south before emptying into Lake Eucumbene after passing over and through the walls of the dam (Society, 2013).

The river flows generally south before emptying into Lake Jindabyne. Currently, the reservoir, which is Lake Eucumbene has a total capacity of 4798 GL with an active capacity of 4366.5 GL. The total catchment area of 683 km² and surface area of 14542 ha and maximum water depth of 107m. Currently, the Snow Scheme is one of the major tourist destinations since there are numerous sightseeing driving tours to the major locations of the Scheme 

(Victoria, 2009). The Snowy Scheme Museum was opened in 2011 at Adaminaby to profile the history of the Scheme. The Snowy Hydro has also established its gas-fired power station so as to minimize risks to the business as a result of its reliance on water as a source of energy and a potential effect of transmission restrictions on the capability of remotely positioned Hydro generation assets to access the electricity grid (Stephens, 2010).

Maintenance

The construction of the Eucumbene Dam and the filling of the reservoir behind the current weight on the sides and of a valley. The tress of water linearly increases with its depth. Hence the level of stress of the dam must be determined the advance of the structure ensure that the threshold of the break level is not exceeded. The overflow or overtopping of the Eucumbene Dam beyond its spillway capacity may result in its eventual failure. Currently, there has been the establishment of overtopping protection systems to protect the Eucumbene Dam such as precast concrete block protection, embankment overflow steeped spillways, minimum energy loss weirs, reinforced earth, gabions, and timber cribs (Weaver, 2012).

System Planning

Conclusion

This is an assessment paper that seeks to analyze the design process of the Eucumbene Dam by majorly focusing on the conceptual design phase of the Eucumbene Dam. The major reason for the design and construction of the Eucumbene Dam is for the purposes of hydroelectric power and also for the purposes of irrigation in the complex constructed in south-east Australia. The design and construction process of Eucumbene Dam began in 1956 and was later completed in 1958 making it the major dam within the region. Eucumbene Dam is an earth-fill type of an embankment dam since it is made of compacted earth. An embankment dam’s cross-sectional area displays a shape like a hill or a bank with a core made of an impervious material to discontinue seeping through of water in the dam.

Allan, C., 2010. Adaptive Environmental Management: A Practitioner's Guide. Perth: Springer Science & Business Media.

Association, I., 2010. Water for Human Needs: Development and meteorology. Minnesota: Indian Committee for IWRA, Central Board of Irrigation and Power.

Golzé, A., 2009. Handbook of dam engineering. Gold Coast: Van Nostrand Reinhold Co..

Guyer, P., 2018. An Introduction to Manual Layout of Arch Dams. Perth: Guyer Partners.

Hanna, W., 2012. The design of dams. Perth: McGraw-Hill book company, inc..

IPC, 2010. International Water Power & Dam Construction, Volume 28. London: IPC Electrical-Electronic Press,.

Jackson, D., 2011. Building the Ultimate Dam: John S. Eastwood and the Control of Water in the West. Melbourne: University of Oklahoma Press.

Jansen, B., 2012. Advanced Dam Engineering for Design, Construction, and Rehabilitation. Sydney: Springer Science & Business Media.

Leslie, J., 2013. Deep Water: The Epic Struggle over Dams, Displaced People, and the Environment. Perth: Farrar, Straus and Giroux.

Martin, W., 2014. New Developments in Dam Engineering: Proceedings of the 4th International Conference on Dam Engineering. Sydney: CRC Press.

Pedro, J., 2009. Arch Dams: Designing and Monitoring for Safety. Melbourne: Springer Science & Business Media.

Society, R., 2013. Proceedings of the Royal Society of Victoria, Volume 117. Melbourne: Royal Society's Hall, .

Stephens, T., 2010. Manual on Small Earth Dams: A Guide to Siting, Design and Construction. Toledo: Food and Agriculture Organization of the United Nations.

Thomas, H., 2010. The engineering of large dams, Volume 2. Michigan: University of Michigan.

Victoria, M., 2009. Occasional Papers from the Museum of Victoria, Volumes 1-5. Victoria: Museum of Victoria.

Weaver, K., 2012. Dam Foundation Grouting. Gold Coast: American Society of Civil Engineers.