Jschwagl, the extra property taxes, beyond prop 13, must be voted on by those subject to the additional tax. A local ballot initiative will propose that something be paid for with a bond to be paid with extra taxes. Typically it is a water and or sewage improvement for an area. An area of 500 acres say is four miles out of town but does not have city water or sewage. People must build a well and install a septic system. That can be expensive and it might be impossible because of soil conditions or water availability. The 30 million dollar bond connecting to the city water and sewage system will probably dramatically increase the value of the covered area. The bond raising the $30 million cost might be a ten year bond or a twenty year bond. After the bond is paid the extra tax ends. People don’t have to vote yes. But if a majority in the area covered do vote yes tax goes up. But it is not that common.