Our People

photo of Michael Hogan

Michael Hogan, MS, CPESC


Michael Hogan is a soil scientist with more than 30 years of experience with erosion control, restoration, and applied research. Mr. Hogan founded Integrated Environmental Restoration Services (IERS) in 1995 and has been instrumental in developing and implementing a range of practices in the Lake Tahoe Basin that have improved performance of erosion control and restoration projects. These practices include use of advanced soil physical and biological treatment, development and use of statistically defensible monitoring protocols, and development and use of an applied adaptive management system that is being adopted and used widely throughout the West and beyond. Mr. Hogan and IERS are engaged in active research partnerships to develop and demonstrate the most effective restoration-based technology for drastically disturbed sites in the Sierra Nevada. Mr. Hogan incorporates proactive partnerships designed to find comprehensive win-win solutions to erosion and related environmental issues. When he is not working, Michael enjoys playing guitar, bike riding and skiing of all kinds.
  • M.S. Soil Science, focus on disturbed site nutrient cycling and restoration; UC Davis
  • B.S. Soil and Water Science, UC Davis

photo of Mark Grismer

Mark Grismer, PhD PE


Mark Grismer has been a Professor at U.C. Davis for 35 years and is a CA registered Civil Engineer. Dr. Grismer is a specialist in vadose zone hydrology, watershed processes and water quality. His teaching includes courses in general hydrology, infiltration, irrigation and soil erosion-restoration processes. With more than 125 peer-reviewed publications covering a broad range of topics related to soil physics, irrigation/drainage, groundwater, evapotranspiration, constructed wetland treatment systems and watershed modeling, he has developed knowledge about basic processes while crafting applied solutions or guidance. He combines field and laboratory measurements with modeling to address practical water quality problems of concern to land owners, managers and regulators. Mark spends his free time running, biking swimming and coaching.
  • Ph.D. Agricultural Engineering, Emphasis: Groundwater Hydrology; Colorado State University
  • M.S. Environmental Engineering, Emphasis: Hydrology and Water Quality; Oregon State University
  • B.S. Agricultural Engineering, Emphasis: Soil and Water Science; Oregon State University
  • PE Civil Engineering, California, #72703

photo of Gerald Rockwell

Gerald Rockwell


Gerald Rockwell is a ground and surface water quality specialist with 35 years of experience with the USGS, including 13 years as the USGS Tahoe Field Office Chief. From 1974-77, Mr. Rockwell worked with early modelers to help describe groundwater quality and quantity in California’s Central Valley from the USGS office in Sacramento. There, he authored or co-authored several reports on groundwater quality. Mr. Rockwell relocated to the Tahoe Field Office in 1978 and shifted his focus to surface water quality and quantity. During his 30 year tenure in the Lake Tahoe office, he contributed to or co-authored annual reports on surface water hydrology and water quality data from more than 350 locations in the Sierra Nevada. From 1995-2008, Mr. Rockwell served as the USGS Tahoe Field Office Chief. His duties included personnel management, program development and management, QA/QC of all data collected, database management, and annual data publication. In 2005 and 2006, he was selected as a member of the USGS headquarters team that performed a tri-annual review of the USGS West Virginia and Montana water science centers.

photo of Debbie Kelly-Hogan

Debbie Kelly-Hogan


Debbie Kelly-Hogan is the Business Manager of Integrated Environmental Restoration Services, Inc. She has over 25 years of experience in ski resort management serving as Director of Sales for Squaw Valley and Director of Human Resources for Northstar resorts. Debbie enjoys spending time outdoors, skiing, bike riding, hiking and gardening.
  • B.A. Business Administration, Chico State University