Over 90% of the land in Dallas County is located in a city. Since, in Texas, usually only cities - and not counties - have the authority to adopt zoning and building ordinances, if you are interested in finding out what type of zoning is permitted or what type of building or sign can be constructed at a particular address in a city, please call that city.

Less than ten percent of the land in the County is not located in a city. Much of this land is considered to be in the federally-designated floodplain. If you are interested in platting, subdividing, or building on any of the land that is not located within a city, please call the County's Public Works Department at 214.653.7151 to see what rules and procedures must be followed.

If you are interested in using a septic tank on land that is not located in a city, please call the County's Health and Human Services Department at 214.819.2115. If you would like to build a commercial structure in the area outside of a city, please call the County Fire Marshal at 214.653.7971 to see what fire codes might apply.