UCA Young Members invite you to join
them for the webinar:
Wednesday, August 31, 2016, 10:00 am MT.
Speaker: Randall Essex, P.E., Executive V.P. Mott MacDonald
UCA webinars are funded by the UCA Division of SME and are provided at no
cost to participants.
Randall Essex, Executive VP, Director
of Professional Excellence & Practices, Mott MacDonald, will present a case
history on the Lake Thistle Emergency Drainage Project. A 25 million cubic yard
mudslide formed an un‐engineered, 225‐foot high dam across a river canyon near
Spanish Fork, Utah. The mass of montmorillonite, judged the sixth largest
landslide in the history of North America, completely blocked the flow of the
Spanish Fork River, and formed a 60,000 acre‐foot, 200‐foot deep lake. The
impounded run‐off completely engulfed the town of Thistle, situated ½ mile
upstream of the slide, and submerged the town beneath 175 feet of water.
A team of engineers and engineering
geologists was retained to design and engineer an emergency system to drain the
lake as quickly as possible, and provide a permanent diversion for the river
around the slide‐dam. The system included a 2,230‐foot long, 13‐foot wide drill‐and‐blast
rock tunnel, a 16‐foot diameter, 180‐foot deep shaft, a bulkhead and twin
valves at the base of the shaft to control lake water discharge, and a
sequentially deepened channel excavation between the lake and the shaft.
About the speaker: Mr. Essex holds a B.S. in
Geomechanics from the Univ. of Rochester, two Master degrees from
the University of California, Berkeley, and is a Professional
Engineer in five states. He has authored over 40 technical papers and is
the principal author of the 2007 ASCE Guidelines document
“Geotechnical Baseline Reports for Construction.” Mr. Essex is the
Executive Vice President and Director of Professional Excellence and
Practices for Mott MacDonald. He is the
current US Representative to the International Tunnelling Association and
was recently awarded the prestigious Golden Beaver Award
for Engineering.
Register now for this informative
webinar:
- Go to: https://smenet.webex.com.
- Find the webinar you want to attend, then click the
"Register" button.
- Follow the directions provided on the page to complete
your registration.
