Suma Park Reservoir Spillway Investigations

Client: Snowy Mountains Engineering Corporation (SMEC)
Year: 2006 to date
Project Reference: 05035
WRL Technical Report: Suma Park Dam Physical Model Investigation (2006/32)

In 2006 WRL was commissioned to undertake a physical model investigation of a proposal to raise and lengthen the spillway of the arc dam wall. This proposal was to accommodate the NSW Dam Safety Committee flooding requirements which are for the dam spillway and associated downstream controls to safely discharge floods up to the Probable Maximum Flood (PMF).

A 1:60 scale model of the dam wall, downstream control works and topography upstream and downstream of the wall was constructed at WRL. The dam wall was constructed from rolled steel and the spillway ogee crest from specially routed Perspex. The hydraulic loads were measured by 32 peizometers and 6 rapid sampling pressure transducers. Flows were measured by a calibrated electromagnetic flow meter and velocities throughout the model by pigmy propeller type current meters.

The investigation directed a number of design changes which had major implications on the cost of the project. The original chute and walls to control the flood waters as they plunged over the spillway had to be widened and walls raised, and the model also determined the contours of the concrete chute floors. The hydraulic loads as measured by the network of peizometers and pressure transducers, provided data for structural engineering design.