Extended Bios



Liz Kirkwood, Executive Director

As an environmental lawyer with over 20 years of experience working on water, sanitation, energy, and environmental governance issues both nationally and internationally, Liz serves as the organization’s lead on numerous Great Lakes issues and education initiatives. Often testifying or speaking before public bodies, she has made frequent presentations to community organizations and professional audiences on Great Lakes issues from Line 5 to water justice and infrastructure financing to water privatization to climate change.  Liz develops and oversees FLOW’s work on key Great Lakes environmental policies designed to promote healthy ecosystems, thriving communities, and access to safe, clean, affordable water for all.  

Prior to joining FLOW in 2012, Liz worked for USAID in Thailand as an environmental attorney to implement a regional environmental governance, water, and sanitation program in Southeast Asia. She also worked as an environmental litigator at Farella, Braun & Martel in San Francisco where she represented clients on natural resource and energy related matters. Liz graduated from Williams College with a degree in Environmental Studies and History, and received her J.D. and Environmental Certificate from Lewis & Clark Law School. Liz currently serves as a member of the International Joint Commission’s Water Quality Board.

Read more about Liz Kirkwood here: Liz Kirkwood, Executive Director of FLOW, is Our Great Lakes GuardianTraverse Magazine, August 2019.


Dave Dempsey, Senior Advisor

Dave Dempsey has 35 years’ experience in environmental policy. He served as environmental advisor to former Michigan Governor James Blanchard and as policy advisor on the staff of the International Joint Commission.  He has also provided policy support to the Michigan Environmental Council and Clean Water Action.  He has authored several books on the Great Lakes and water protection.

Dave has a bachelor’s degree from Western Michigan University and a master’s degree in environmental policy and law from Michigan State University. He has served as an adjunct instructor in environmental policy at both universities.
Read more about Dave Dempsey here: Great Lakes for Sale: Veteran activist and author puts renewed spotlight on diverting Great Lakes water by Gary Wilson, Great Lakes Now, Dec. 1, 2021.

Tessa Diem, Development Specialist

Tessa Diemhas worked in the nonprofit sector since 2014, serving environmental and cultural organizations to advance their missions through program coordination, strategic planning, resource development and communications. Her project and field work in aquatic ecology, biodiversity and climate change has explored the connections between society and the environment to address how we can utilize creative and impactful solutions to address the challenges of our time.

Prior to joining FLOW, Tessa worked with The Baum Foundation and Native Conservancy to develop a sustainable kelp farming model to serve Native and rural communities in Prince William Sound, Alaska. Tessa earned her B.S. in Environmental Science from the University of Michigan with a concentration in water resources and a deep love for the rivers, lakes and wetlands of Michigan.  

What connected you to the Great Lakes: Growing up camping on the shores of Lake Michigan. Every day the lake offered a different personality, sometimes calm, even placid, other days exerting its power. I learned to observe and listen to nature and the Lake was such a good teacher for that.

Favorite place in Michigan: Anywhere I can connect with our geologic history—hiking along the glacial moraines, on the beaches nestled under ancient dunes or along the crisp, clear waters of a spring-fed creek. So many special places to feel a connection.

Favorite Great Lakes fact: Only one percent of the water in the Great Lakes system is replenished each year. The rest is the legacy of glaciers. In other words, the Great Lakes are a finite resource that must be protected!

Read more about Tessa Diem here:FLOW Welcomes Development Specialist Tessa Diem, February 7, 2022.


Diane Dupuis, Development Director

Diane works to connect FLOW with resources that can help fuel the work of safeguarding the Great Lakes for all. After earning a BA in French and English from Kalamazoo College, Diane embarked on a career in publishing that culminated in a position as Publisher of Visible Ink Press. Pivoting to the nonprofit sector, she spent ten years serving Interlochen Center for the Arts in communications and fund-development roles before fundraising for two land conservancies in Michigan, and for the Ann Arbor Art Center. Past volunteer affiliations include Pathfinder School, Parallel 45 Theatre, Michigan Writers, and Washtenaw Literacy; she now serves as Vice Chair of Michigan Audubon.

Read more about Diane Dupuis here: Make It Rain | Diane Dupuis Is Here to Help Us Fund the Fight of the Great Lakes’ Life by Ross Boissoneau | Nov. 16, 2019.


Jim Olson, Founder & Senior Legal Advisor

Jim Olson has nearly 40 years of experience as an environmental, water, and public interest law advocate and champion, dedicated to protecting waters and ecosystems in the Great Lakes Basin.  He has developed a deep knowledge and understanding of public trust principles and law as they apply to the systemic threats facing the Great Lakes Basin. Jim currently contributes to FLOW’s legal and policy work, including policy analyses, law review articles, comments, reports, and other publications. He also speaks on behalf of the organization through presentations, lectures, and panel discussions. He has lectured at every major university in Michigan, authored dozens of articles on the public trust, and litigated many relevant cases.

Jim is a graduate of Michigan State College of Law (Detroit College of Law) and has an L.L.M. Degree in public lands, natural resources, and environmental law from the University of Michigan Law School. He received the Champion of Justice Award in 2010, one of the highest honors of the Michigan Bar Association, and was named a Michigan Lawyer of the Year in 1998 for his work on environmental and water citizen suit laws. Jim has lectured in Brazil, Canada, and the United States, and has authored numerous articles and essays and three books.  He was featured in two eminent documentary films on water, “FLOW: For Love of Water” (2008) and “Blue Gold” (2008).

Read more about Jim Olson here: Traverse City Attorney is Defender of Global Water by Lissa Edwards | Traverse Magazine | Sept. 28, 2011.


Kelly Thayer, Deputy Director

As deputy director, Kelly works to grow FLOW’s reach, revenue, programs, and partnerships. Kelly has worked with FLOW since 2014, initially as a communications consultant helping to coordinate and support FLOW’s involvement in the Oil & Water Don’t Mix campaign to shut down the aging, cracked, and encrusted Line 5 oil pipelines in the open waters of the Mackinac Straits, where Lake Michigan and Lake Huron meet.

Kelly’s experience includes research, writing, and organizing communities. His leadership skills include working with local, state, and national environmental campaigns. He served as volunteer co-chair of successful election campaigns to launch a countywide public bus transit system in 2006 and renew its funding by a 3-1 margin in 2011 in Benzie County. Kelly also helped to build and co-direct state and local coalitions to advance people-centered transportation policies and projects in Michigan from 1998-2005 while working with the Michigan Land Use Institute.

For more than a decade thereafter, Kelly worked as a consultant at The Resource for Great Programs, a national firm working to strengthen foundations that support, and nonprofit law firms that provide, free civil legal aid to people in poverty across the nation. Kelly volunteered in the U.S. Peace Corps in Tanzania, East Africa, where he and his wife Carolyn served as village-based volunteers for two years. He earned a Master of Arts in Journalism and a Bachelor of Arts in English Literature from the University of Michigan.

Read more about Kelly Thayer here: Milestones–Kelly Thayer Shares Memories and Takeaways from Bridge and Bypass Battles in TC and Petoskey! October 17, 2020 | By Jeff Smith.


Zach Welcker, Legal Director

Before joining FLOW, Zach Welcker spent more than a decade representing Indian tribes in the Pacific Northwest on water, fisheries, and other natural resource issues.  He was an associate attorney at Kanji & Katzen, PLLC from 2009-2012 and worked as a legal and policy advisor for the Kalispel Tribe of Indians from 2012-2021.

Zach began his legal career as a law clerk for the Honorable Procter Hug, Jr. with the U.S. Court of Appeals for the Ninth Circuit.  He graduated from the University of Oregon School of Law.

What connected you to the Great Lakes: My childhood, my people, da Bears, and the water.

Favorite place in Michigan: This week, a beach in Suttons Bay.

What’s a fun fact about you: Both of my kids were born in the water.

Read more about Zach Welcker here: Jim Olson Passes the Torch to Zach Welcker, FLOW’s First Full-Time Legal Director | FLOW | Dec. 9, 2021.


Jacob Wheeler, Communications Coordinator

Jacob edits and publishes the Glen Arbor Sun, a seasonal, biweekly newspaper that celebrates and tells stories about Leelanau County’s unique characters and places: he founded the Sun when he was 18, partly as a way to pay for his studies at the University of Michigan. He also teaches journalism and advises the White Pine Press student newspaper staff at Northwestern Michigan College in Traverse City.

Born in Denmark and raised in rural Leelanau County, Jacob holds dual citizenship and (on a good day) speaks four languages. On cold, grey winter days, he sometimes dreams of Guatemala, where he spent his mid-20s, living in a Mayan highland village, learning Spanish, hiking volcanoes, and writing a book, Between Light and Shadow (University of Nebraska Press, 2011), about the country’s child adoption industry.

Jacob’s favorite ways to cherish the Great Lakes include swimming (9 months a year!) in Lake Michigan’s holy waters or running or biking along her shoreline. The concept of the Public Trust—as policy, as a community, and as a spiritual rallying cry—resonates deeply with him.

Read more about Jacob Wheeler here: Jacob Wheeler, That One Guy, Jan. 13, 2021, The Betsie Current.