Name

Item

Description

TOP OF DAM

1135.5 m

FLOOD CONTROL ZONE

1135 m

Induces surcharge

Release water from Spillway using defined release discharge

Forces flood flows over the spillway

CONSERVATION ZONE

Varies between 1134.5 and 1135 m

This is the range of the guide curve elevation. Calculation is done in Excel

Nnywane IF Functions

ELSE IF Nnywane Dam Pool >1135 m

Maximum release of 0.15 cms

Spillways open

ELSE IF Nnywane Dam Pool >1129 and <1135 m

Normal release of 0.021 cms

Spillways closed

Controlled outlet open

IF Nnywane Dam pool ≤1129 m

Maximum Release of 0 cms

Spillways are closed

Controlled outlet closed

INACTIVE

1129 m

Dead storage, no releases below this elevation