Figure 9. First weir installed at Craney Island CDF

ERDC TN-DOER-T3

January 2001

A foundation to anchor the weir structure to

the bottom of the placement site in which it is

installed.

A framework to support the machinery that is

used to adjust the weir height.

A set of jackscrews to raise and lower the

crest of the weir.

A motor and gear mechanism to drive the

jackscrews.

Control circuitry.

A battery power supply.

A solar panel to maintain the batteries in a

charged state.

A weatherproof enclosure for the controls.

A discharge pipe adapter.

A weir head gauge.

The weir itself consists of a set of nested cylin-

ders set on end with their axes vertical. The bot-

tom cylinder is fixed to a steel frame foundation

Figure 9. First weir installed at Craney Island CDF

that is anchored to a concrete pad at the bottom

of the placement site and connected to a dis-

charge pipe (Figure 10). The upper cylinders are extended in a telescoping manner to position the

rim of the top cylinder to any desired elevation below or above the water surface (Figure 11). As the

cylinders are lowered below the water surface, the decant water flows over the weir crest into the in-

terior sections, exits through the discharge pipe in the lower section, and returns to the nearby water-

way (Figure 12).

Figure 11. Extended telescoping cylinders at

Figure 10. Anchor and foundation of

Blakeley

telescoping weir