Within all areas designated as floodplain primary under Chapter 17.42 of this code or included within the state regulatory floodway, encroachment, including fill, new construction, substantial improvements, and other development is prohibited unless hydrologic and hydraulic analyses by a registered professional engineer are provided demonstrating that encroachments shall not result in any increase in flood levels during the occurrence of the base flood discharge, except as the purposes set forth in Section 17.42.020 are otherwise accomplished. (Ord. 5062 § 1, 2021; Ord. 4469 § 1, 2007)