Nuisance defined. Every act or thing done, or anything existing within the limits of any city referred to in ORS 221.906, which is or may be declared by any law of this state or by any ordinance of such city to be a nuisance, hereby is declared to be a nuisance, and shall be considered and treated as such in all actions, suits and proceedings whatsoever, unless such law or ordinance is declared void by a court of competent jurisdiction

ORS 221.915 — under Chapter 221.