Press Release

Sevim Onsoy joins GEI as Senior Groundwater Leader in Sacramento

May 30, 2024

Sevim brings technical leadership in water resources planning and management

Portrait of Sevim Onsoy

Sacramento, CA (May 30, 2024) Sevim Onsoy, Ph.D., has joined GEI Consultants in Sacramento as a Senior Groundwater Leader. Sevim brings nearly two decades of diversified technical knowledge as well as leadership in project management, business development, and team mentorship.

“Sevim possesses a high level of experience in groundwater planning given her outstanding academic achievements and project experience,” says Chris Petersen, P.G., C.H.G., Vice President and Groundwater Team Lead at GEI. “Sevim’s valuable background and knowledge in the use of numerical tools to answer both water quality and quantity questions will enable our California groundwater team to offer expanded groundwater modeling solutions to clients.”

Sevim is an expert in nitrate occurrence and mobilization in agricultural areas. She has spent many years of her career developing and running numerical groundwater models applied to both the occurrence and mobilization of nitrate in groundwater and for groundwater sustainability planning.

“I have been impressed with GEI’s team culture of collaboration and the breadth of expertise across different practice areas,” says Sevim. “I look forward to collaborating with the highly motivated staff and senior leaders on challenging groundwater issues, including sustainability, conjunctive use, aquifer recharge, and salt and nitrate impacts on water supplies. I am very excited about being part of GEI’s growing team and future success.”

Sevim holds a Ph.D. and a Master of Science in Hydrologic Sciences from the University of California Davis, as well as a Bachelor of Science in Agricultural Engineering from Ankara University in Turkey. She has authored numerous publications and received awards for excellence in project delivery.


About GEI: GEI Consultants, Inc. is a consulting engineering firm that delivers professional services that improve our world’s built environment. With more than 1,400 staff and more than 50 offices in North America, GEI is a leader in providing multi-disciplined engineering and environmental services to a range of private and public sector clients, both domestically and abroad.

As a member of the employee-owned GISI family of companies, we foster personal relationships with our clients and support our staff in a partnership model, which is underpinned by continuous learning and sharing of knowledge. We retain proven, recognized experts and attract the best minds to deliver to our clients a refreshing blend of technical expertise, collaborative spirit, and innovation that is rare in our profession. We engineer solutions in five primary end markets: Water Resources, Energy, Buildings, Infrastructure, and Industrial. For more information on GEI, please visit

Media Contact:

Rachel Sa
Director of Communications
GEI Consultants
(647) 988-9300