Design and construction of an embankment dam in New South Wales, Australia

Abstract

Dams are built for several reasons such as to create reservoirs that capture water from streams and store the water to be used throughout the year and during drought years. Dams also provide irrigation water, drinking water, hydropower, and flood control. Many reservoirs provide recreational activities like fishing, boating, and other water sports. Embankment dams are one of the most common types of dams in Australia. Designs of embankment dams usually relate to the degree that seepage is controlled within the dam by provision of filters and drains, by the use of free draining rockfill in the embankment, and the control of foundation seepage by grouting, drainage and cutoff foundation. There are several types of embankment dams depending on what material is used most in the dams. The most common ones are earthfill dams, which are made mostly of soil, and rockfill dams, which are made mostly of rocks. The selection of dam type to be used at a particular site is affected by the availability of construction materials (earthfill, rockfill and filters), foundation conditions, climate, topography and relation to other structures (spillway, river diversion outlet works, etc.), staged construction and time for construction. In design, embankment dam zoning system is used where each zone has its function and typical construction materials. Two types of foundation treatments are adopted i.e. general excavation and cutoff excavation. This paper aims to provide some insights into the design and construction methods of an embankment dam situated in New South Wales, Australia as practiced by the geotechnical engineers in the country. The paper will discuss the available dam options before selecting the best for the site and elaborate the construction method of the selected dam type.