Dimensions of the dams as measured in May 2005
Lower dam:
Long axis 53m, short axis 37m – approximated to a circle of diameter 45m
Radius = 23m
Circumference = 145m
Water surface area = 1660sqm
Deepest point = 2m
Volume = 1/3 area x depth = 1000 m3
Average filter zone width = 3m
Filter zone area = ((radius + fz width) 2 x 3.14) – water surface area = 460 m2
Average dry eroded width = 3m
Dry eroded area = ((radius + fz width + dry width) 2 x 3.14) – water surface area – filter zone area = 520 m2
Upper dam:
Radius = 20m
Circumference = 131m
Water surface area = 1260sqm
Deepest point = 1.7m
Volume = 1/3 area x depth = 700 m3
Average filter zone width = 2m
Filter zone area = ((radius + fz width) 2 x 3.14) – water surface area = 260 m2
Average dry eroded width = 3m
Dry eroded area = ((radius + fz width + dry width) 2 x 3.14) – water surface area – filter zone area = 450 m2
