Auxiliary Spillway Erosion Mitigation Strategies: Instructors

Karl Visser, PE
Freese and Nichols, Inc.
Senior Dam and Levee Engineer

Karl holds a BS and MS degree in Agricultural Engineering from Kansas State University in Manhattan, KS. He is licensed as a professional engineer in Kansas and Illinois and is a Senior Dam and Levee Engineer with Freese and Nichols, Inc. Before Freese and Nichols, he worked for the US Department of Agriculture – Natural Resources Conservation Service in Kansas, Illinois, and Texas from 1982-2025. He served as NRCS liaison for SITES and WinDAM software for hydraulic routing and auxiliary spillway erosion for nearly two decades. He reviewed several hundred dam rehabilitation projects across the US during his time at the NRCS-National Design Construction and Soil Mechanics Center in Ft Worth.  He has visited many eroded/breached non-structural spillways in several states around the United States.

James McNash, PE
Freese and Nichols, Inc.
Senior Engineer / Engineer VI

James is a civil and geotechnical engineer for Freese and Nichols, Inc., practicing in Dams and Levees out of their Charlotte, North Carolina office. He's led or served as the geotechnical engineer for over thirty flood control dams and surface impoundments, evaluating the stability, erodibility, and performance of the embankments and spillways. In addition, he has experience characterizing subsurface stratigraphy, estimating engineering properties, and modeling earthen spillways within both SITES and WINDAM. He holds both a bachelor's and a master's degree from Georgia Institute of Technology, and is a licensed professional engineer in several states within the southeastern US.