She then attended the Norwegian School of Management in Bergen and Trondheim from 1987 to 1990 and 1994 to 1997.
She took lower secondary education in Leirfjord from 1981 to 1984, and upper secondary education in Sandnessjøen from 1984 to 1987. She was mayor of Lindås municipality from 2003 to 2007, and then a municipal council member in the executive committee from 2007 to 2011. She served as a deputy representative to the Parliament of Norway from Hordaland during the terms 2005–2009 and 2009–2013.
She has also been a judge in Nordhordland District Court.
She is bound to a wheelchair.
She chaired her local party chapter from 2002 to 2004, and is a member of the Labour Party central committee from 2007. During the second term she held a regular seat since Anne-Grete Strøm-Erichsen was a member of Stoltenberg"s Second Cabinet. She was a member of the Standing Committee on Labour and Social Affairs.
Brandvik has been a board member of Hordaland Olje og Gass from 2003 to 2007, chaired the Regional Council for Nordhordaland and Gulen since 2007 and been a member of many municipal boards.