All signs, displays, or devices legally erected and maintained within the control zones established pursuant to this chapter and those signs, displays, or devices that are nonconforming to the controls established pursuant to this chapter may not be maintained unless a permit is obtained from the Department of Transportation. A sign, display, or device erected or maintained without a permit is a public nuisance and subject to abatement by the Department of Transportation.

Source: SL 1977, ch 246, § 8; SL 1985, ch 236, § 2.