NEWS 2009

Posted October 6, 2009

Event: October 13, 2009

UofA: AEG/GSA 2009 Jahns Distinguished Lecturer, Dr. Edmund Medley - Forensic Investigation of the Sea Cliff Incident, an Urban Catastrophe

Location: NREF 1-001, U of A Campus

Time: 5:00pm

Shortly after midnight on December 11, 1995, storm water started to leak from a century-old 6-foot brick sewer underlying the prestigious Sea Cliff neighborhood in San Francisco. The leakage eroded vulnerable dune sand soil to create a pit that grew uncontrollably to over 250 feet wide and 40 feet deep. Shortly after dawn, a multi-million dollar home and portions of other properties fell into the pit, events that were broadcast by TV world-wide. Discharge from the sewer continued for several hours, resulting in the undermining of other homes, destruction of part of the Presidio National Park, and eventual overflow of sewage more than two miles away, across the Great Highway and Ocean Beach, into the Pacific Ocean. Dr. Medley, the Principal Investigator for the investigation, shares findings and the lessons learned from the failure.

Edmund Medley, PhD, PE, CEG, F.ASCE is the 2009 Richard H. Jahns Distinguished Lecturer in Engineering Geology. The selection committee for this award is composed of representatives of the Association of Environmental and Engineering Geologists (AEG) and the Engineering Geology Division of the Geological Society of America (GSA). The intent of the partially-funded Lectureship is to encourage student and professional awareness of engineering geology through a series of lectures presented across North America during the award year. The award was established in 1988 to commemorate Professor Jahns (1915-1983), who had an influential and diverse career in academia, consulting and government. Details on the life and career of Professor Jahns are presented at edmedley.com (Jahns Lectures page). The full biography for the lecturer, Dr. Medley can be found on this page.