A. Purpose. The purpose of this section is to establish standards that protect primary conservation areas and public river corridor views from development impacts and ensure that new development is sited consistent with the purpose of the MRCCA.
B. Structure Height. Structures and facilities must comply with the following standards unless identified as exempt in Section 12-3-15.
1. ROS District: the lesser of the height standard as determined by the underlying zoning district or thirty-five feet (35').
2. RN District: the lesser of the height standard as determined by the underlying zoning district or thirty-five feet (35').
3. SR District: height is determined by the underlying zoning district, provided the allowed height is consistent with that of the mature tree line, where present, and existing surrounding development, as viewed from the OHWL of the opposite shore.
4. Height shall be measured on the side of the structure facing the Mississippi River.
5. In addition to the conditional use permit requirements of Section 12-3-3.D, criteria for considering whether to grant a conditional use permit for structures exceeding the height limits must include:
a. Assessment of the visual impact of the proposed structure on public river corridor views, including views from other communities;
b. Determination that the proposed structure meets the required bluff and OHWL setbacks;
c. Identification and application of techniques to minimize the perceived bulk of the proposed structure, such as:
(1) Placing the long axis of the building perpendicular to the river;
(2) Stepping back of portions of the facade;
(3) Lowering the roof pitch or use of a flat roof;
(4) Using building materials or mitigation techniques that will blend in with the natural surroundings such as green roofs, green walls, or other green and brown building materials;
(5) Narrowing the profile of upper floors of the building; or
(6) Increasing the setbacks of the building from the Mississippi River or blufflines.
d. Identification of techniques for preservation of those view corridors identified in the MRCCA Plan; and
e. Opportunities for creation or enhancement of public river corridor views.
C. Location of Structure and Impervious Surfaces.
1. Structures and impervious surfaces must not be placed in the shore or bluff impact zones unless identified as an exemption in Section 12-3-15.
2. Structures and facilities, including impervious surfaces, must comply with the following OHWL setback provisions unless identified as exempt in Section 12-3-15.
a. ROS District: Two hundred feet (200') from the Mississippi River and one hundred fifty feet (150') from the Minnesota River.
b. RN District: One hundred feet (100') from the Mississippi River.
c. SR District: (not applicable in the City of Mendota Heights)
3. Structures and facilities including impervious surfaces, must comply with the following bluffline setback provisions unless identified as exempt in Section 12-3-15:
a. ROS District: One hundred feet (100').
b. RN District: Forty feet (40').
c. SR District: Forty feet (40').
4. Where principal structures exist on the adjoining lots on both sides of a proposed building site, the minimum setback may be altered to conform to the average of the adjoining setbacks, if the new structure's scale and bulk riverward or bluffward of the setbacks required under Sections 12-3-6.C.2 and 12-3-6.C.3 are consistent with adjoining development. [See Figure 7 - below].
FIGURE 7: STRUCTURE SETBACK AVERAGING DIAGRAM
5. Subsurface sewage treatment systems, including the septic tank and absorption area, must be located at least seventy-five feet (75') from the ordinary high water level of the Mississippi River and all other public waters.
D. Lot Size and Buildable Area.
1. Lots abutting the Mississippi River in the ROS District must be at least two hundred feet (200') in width, unless alternative design methods are used that provide greater protection of the riparian area.
2. All new lots must have adequate buildable area to comply with the setback requirements of Sections 12-3-6.C.2 and 12-3-6.C.3 so as to not require variances to use the lots for their intended purpose. (Ord. 568, 9-23-2021)