This webinar will review the current state of the practice for rehabilitation of embankment dams to address seepage issues. Seepage rehabilitation measures can generally be grouped into two categories: seepage reduction / limitation measures and seepage collection measures. Seepage reduction /limitation measures include such features as foundation grout curtains, low permeability blankets, and seepage barrier walls. These measures are intended to reduce or limit the amount of seepage that occurs through, beneath, and around a dam. Seepage collection measures include such features as blanket drains, toe drains, chimney filters / drains, and relief wells. These measures are intended to collect seepage which occurs in a manner that maintains stability of the dam and prevents internal erosion. All of these measures will be reviewed along with discussion of their appropriate applications. Case studies and examples will be used to highlight the applications of the various methods.
John W. France, P.E., D.GE, D.WRE
President, JWF Consulting, LLC
John W. France, PE, D.GE, D.WRE is a registered professional engineer providing consulting services through JWF Consulting LLC. He received BS and MS degrees in civil engineering from Cornell University. John has more than 40 years of consulting engineering experience, during which time he has worked on hundreds of civil engineering projects. For the past 35 years his professional career has been focused on dam engineering and dam safety services. During his career, John has been involved in various capacities in evaluating and remediating seepage issues for earth dams. He has written numerous papers on the topic, and in 2012 he was an invited speaker at a FEMA workshop on filters and seepage remediation. He was engaged by the Montana Dam Safety office to prepare a technical note on chimney filter design for posting on the State’s website, and he has been an instructor for ASDSO’s seepage analysis course; ASDSO workshops on seepage rehabilitation and internal erosion failure modes; and U.S. Army Corps of Engineers’ courses on seepage rehabilitation and embankment dam design. John has participated as facilitator or subject matter expert on numerous risk analyses of internal erosion issues, most recently serving as facilitator for an internal erosion risk analysis for Mosul Dam in Iraq. In 2017, he was the leader of the Independent Forensic Team charged with identifying the causes of the February 2017 Oroville Dam spillway incident.
Jennifer L. Williams, P.E.
Rocky Mountain Dams Business Line Leader, AECOM
Jennifer Williams is a registered professional engineer with 20 years of experience specializing in design, analyses, and construction of earth dams. Ms. Williams is currently one of the managers within the AECOM dams group in the Denver office. She received her BS degree in civil engineering from Colorado School of Mines and MS degree in civil/geotechnical engineering from University of Colorado. Ms. Williams has provided dam safety engineering services including inspection, analysis, design, risk assessment, and construction management to Reclamation, USACE, U.S. Fish and Wildlife Service, NRCS, and several private dam owner and operators. Ms. Williams has presented several dam safety lectures at the Colorado School of Mines and has presented numerous technical presentations at ASDSO and USSD.