Northern Sacramento Valley Branch Meeting-Butte County Stable Isotope Recharge Study

The Northern Sacramento Valley Branch is pleased to present:

Butte County Stable Isotope Recharge Study

Dr. Andrew Kopania, PG, CHG
EMKO Environmental, Inc.


Preliminary evaluation of stable isotope data as part of a study of recharge mechanisms for the Lower Tuscan Aquifer (Brown & Caldwell, 2013) indicated that use of stable isotopes may provide important insights into the sources of runoff within surface streams and subsequent groundwater recharge pathways within Butte County. To further assess the use of stable isotopes as a tool for identifying recharge sources and to gain an improved understanding of groundwater recharge in central Butte County, the Butte County Department of Water and Resource Conservation implemented the Stable Isotope Recharge Study (Brown & Caldwell, 2017). The initial phases of the Stable Isotope Recharge Study included review of existing isotope data in Butte County, along with preparation of a Field Sampling and Analysis Plan to obtain stable isotope data from 30 groundwater wells at 10 individual locations and from 10 separate surface-water locations along creeks and rivers. Samples were collected by Butte County staff in October 2015, June 2016, October 2016 and March 2017. Thus, samples were collected near the end of an historic drought period in 2015, at the end of seasonally wet and dry periods in 2016, and during one of the wettest winters on record in early 2017. Key findings of the Study relate to isotopic variation by season in surface water, isotopic variation by area in groundwater, identification of the primary source water regions for recharge, and recognition of differing recharge mechanisms in different areas of the basin. Within the main surface water bodies, stable isotope abundance varies seasonally in the creeks that flow into the Valley from the watersheds to the east (e.g. Butte Creek, Big Chico Creek, Little Chico Creek).


Dr. Andrew A. Kopania is President and Principal Hydrogeologist at EMKO Environmental, Inc., specializing in groundwater flow and groundwater/surface water interactions. He has a multi-disciplinary academic background, with Bachelor of Science (UCLA) and Master of Science (University of Michigan) degrees in geology and a Doctorate in Environmental Science and Engineering (UCLA). Dr. Kopania is a licensed Professional Geologist and a Certified Hydrogeologist in California. He has 30 years of experience conducting and managing subsurface investigations, long-term field monitoring programs, groundwater modeling evaluations, technical report preparation, regulatory compliance and agency negotiations, and litigation support/expert witness services at industrial and manufacturing facilities, mining projects, solid waste landfills, petroleum pipelines, municipal and state agencies, water purveyors, agricultural operations, and commercial and residential developments.


No-Host Social and Registration- 5:30-6:00 p.m.
Announcements & Dinner - 6:00-6:30 p.m.
Keynote Speaker - 6:30-7:30 p.m.
Questions & Answers - 7:30 - 8:00 p.m.


Members: $25.00
Non-Members: $30.00
Students: $15.00

  • If you register after Noon on Wednesday, February 7th, or walk-in, a $5.00 surcharge will be added to the meeting cost. 
    (Excluding Students)


-Mavarati Mushroom Burger
-BBQ Pulled Pork
-Fish Tacos
-Chinese Chicken Salad

  • If you register after Noon on Monday, November 6th, or walk-in, a $3.00 surcharge will be added to the meeting cost.
  • Cancellations must be made by Noon on Monday, November 6th.

If you have questions about the meeting, please call Eddy Teasdale at 530-503-5877 or email him at


Event Files


Thu, Feb. 8, 2018
5:30 p.m. - 8:00 p.m.

Event has ended


Nash's Restaurant
1717 The Esplanade
Chico, CA 95926