Dalrymple said Friday the declaration allows the state to bring greater resources to bear if local officials need help addressing safety concerns.
Over two dozen protesters have been arrested since last week for interfering with the construction of the $3.8 billion Dakota Access Pipeline that's designed to carry North Dakota crude to Illinois.
Developers have agreed to halt construction of the project in southern North Dakota until a federal court hearing next week.
Dalrymple says the state is committed to protecting lawful assembly rights, but says unlawful acts have led to "serious public safety concerns."
The order doesn't include activation of the North Dakota National Guard.