View Oakland City Council Districts in a larger map
As with the neighborhoods map, any errors are likely mine, not from the source map. In many places the district boundaries follow roads or streams, but I had to make a few guesses here and there, and the areas over the bay are approximations based on the original map.
How are the districts divided? According to the city charter, it's based on the previous districts, but every 10 years after 1993 or if significant territory is annexed the boundaries can be adjusted:
Section 203. Nomination and Election of Councilmembers... The districts shall be as they exist upon the taking effect of this section, until revised by ordinance. In the year 1993, and every ten years thereafter, and whenever any substantial territory is annexed to or consolidated with the City, the Council shall form new districts not exceeding seven. Districts shall be composed of contiguous territory, as equal as possible in population, and as geographically compact as practicable. No change in the boundary of a district shall operate to exclude an incumbent from office before the expiration of the term for which he was elected or appointed.