N.D. Cent. Code § 2-06-15: Tax levy by county, city, or township for airport or airport authority purposes

A county, city, or township supporting an airport or airport authority may levy up to four mills for airport or airport authority purposes. If any city or township within the county is levying a tax for support of an airport or airport authority and the total of the county and city or county and township levies exceeds four mills, the county tax levy within the city or township levying under this section must be reduced so the total levy in the city or township does not exceed four mills.