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The Regional Water Authority (RWA) and Sacramento Groundwater Authority (SGA) are pleased to welcome two water professionals to our team to guide groundwater programs in the Sacramento region.


Trevor Joseph, PG, CHG., Manager of Technical Services

Trevor Joseph is an industry veteran with 25 years of experience and extensive groundwater expertise both at the state level and within the Sacramento region.

He was instrumental in developing the state’s regulatory and implementation framework for the Sustainable Groundwater Management Act (SGMA) while with the California Department of Water Resources (DWR). He also provided guidance and recommendations on key policy decisions and managed implementation of the act while working in DWR’s Sustainable Groundwater Management Office (SGMO).

Prior to working on the SGMA, while at DWR, Trevor also managed groundwater substitution transfers working closely with Sacramento Valley water agencies and State Water Contractors. He also administered over $250 million in funding statewide under the Integrated Regional Water Management Planning grant program.

Most recently, Trevor managed the City of Roseville’s groundwater program as a hydrogeologist for Roseville’s Environmental Utilities department. This included optimizing and expanding Roseville’s conjunctive use capabilities through direct recharge, storage, and recovery of water through the expansion and use of Aquifer Storage and Recovery (ASR) wells. He also oversaw activities and programs designed to safeguard Roseville’s water supplies and provided support on groundwater partnerships at both regional and state levels.

Registered as a professional geologist and certified hydrogeologist in the State of California, Trevor holds a bachelor’s degree in geology from California State University, Sacramento.


Raiyna Villaseñor, Associate Project Manager

Raiyna Villaseñor joins RWA as an Associate Project Manager for the Sacramento Groundwater Authority.

She comes to SGA with experience on a variety of environmental projects supporting the rehabilitation, restoration and management of surface water, groundwater, and flood management plans and projects. Previously, she worked with Environmental Science Associates (ESA) within their Northern California Water group where she served in a variety of different roles, including deputy project manager, project coordinator, agency engagement liaison, environmental analyst, and fisheries biologist.

Raiyna holds a bachelor’s degree in Environmental Studies with a minor in Biology from the California State University, Sacramento.