SMALL DAMS PETITS BARRAGES

2.1 INTRODUCTION
2. TYPES OF SMALL DAMS
Small dams may be grouped into different categories, such as:
� Use
� Hydraulic Design
� Type of Materials
In this bulletin it will be adopted that dam types are defined in accordance with the
material used in their construction, as illustrated in the following examples. Most of the types
are the traditional, while others are the new ones, like the inflatable dam using a special
rubber.
2.2 HOMOGENEOUS EARTHFILL DAMS
Earthfill dams are the most common type of dam, principally because their construction
involves the use of materials from the required excavations and the use of locally available
natural materials requiring a minimum of processing. Homogeneous dams are mostly adopted
where cohesive soils are found abundant. They are also preferable for gravelly cohesive soils
(residual soils) as well as loess. However, such dams have a flatter slope, consequently, a
greater volume of embankment, as illustrated bellow with some small dams built in China [1]
and USA [2].
Fig. 2.1 – Hongshiyan homogeneous dam, China [1].
Fig. 2.2 – Crane Prairie Dam (1939 - 40), USA [2].
1 Rip-rap
2 Silty clay
3 Grass sod
18