Dennis was elected to the McKinleyville Community Services District Board on September 10, 2008.  He is also a past member of the Humboldt County Planning Commission, serves on the Association of California Water Agencies (ACWA) statewide Board and the ACWA Region 1 Board, is a lobbyist for the California Commercial Beach Fisherman's Association, and was a founding member of the Humboldt Open Door Clinic. Dennis is a local organic rancher and horse breeder and is active in the Pony Express Days, McKinleyville Rodeo Association and California State Grange.