Del. Code tit. 22 § 105
The General Assembly shall not enact any law which removes real property from within the limits of any city or incorporated town in this State until after the question of such removal shall have first been submitted to the governing body of the city or incorporated town at a special election of qualified voters and real estate owners of the city or incorporated town. The governing body of the city or incorporated town must first grant its approval by affirmative vote of a majority of the members of the body. When a special election is held, a majority of the qualified voters and real estate owners in the city or incorporated town must approve the removal from within the limits of the city or incorporated town and only then shall the real property be removed from the assessment rolls of the city or incorporated town. Any special election shall be held by the proper election officers of the city or incorporated town. The voting requirements shall be the same as those that exist for all other municipal elections in the municipality involved.
22 Del. C. § 105