In all areas of special flood hazard where the Flood Insurance Study provides base flood elevation data as set forth in Section 1311.07, but no floodways have been designated, the following provisions apply:
(a) New construction, substantial improvements, or other development (including fill) shall only be permitted if it is demonstrated that the cumulative effect of any proposed development, when combined with all other existing and anticipated development, shall not increase the water surface elevation of the base flood more than 1.0 (one) foot at any point.