Alden conducted a comprehensive, multi-faceted flow model study of the addition of a proposed storm water tunnel in Austin, TX.  Waller creek has historically had problems with flooding, erosion and water quality. The tunnel, a morning glory spillway, two lateral entrances and the discharge structure were all modeled.

Alden designed, constructed and tested an undistorted, 1:33 scale comprehensive  physical model of the Waller Creek Tunnel.  The main morning glory spillway, two secondary spillways and the tunnel discharge were modeled.  The model was used to evaluate flow patterns and flow splits approaching the morning glory spillway, the entrainment of air at the spillway and the pressure losses in the system.

In addition to the physical model, a 3D numeric model using Flow-3D was developed to examine the flow patterns into the morning glory spillway and the flow patterns entering the tunnel from the downstream laterals.  Modifications were developed in CFD and tested in the physical model to minimize the number of modifications required to the physical model to arrive at acceptable flow patterns.