Agenda - Council - 08/08/2023 - Laserfiche WebLink

Home

1 permit consistent with provisions of section 117 148(j)(6) (conditions of land altcratie- 2 p-ermit approval) provided that: 3 1. If the project includes work at or below the OHWL, the commissioner has already 4 approved or permitted the project. 5 2. The structures are used only to correct an established erosion problem as determined 6 by the City of Ramsey. 7 3. The size and extent of the structures are the minimum necessary to correct the erosion 8 problem and are not larger than the following, unless a professional engineer 9 determines that a larger structure is needed to correct the erosion problem: 10 (i) Retaining walls must not exceed five feet in height and must be placed a minimum 11 horizontal distance of ten feet apart; and 12 (ii) Riprap must not exceed the height of the regulatory flood protection elevation. 13 c. Repair of existing rock riprap, retaining walls, and other erosion control structures above the 14 OHWL does not require a permit provided it does not involve any land alteration under 15 section 117 148(j)(2) (land alteration permit). 16 (4) Stormwater management. 17 a. In the bluff impact zone, storm water management facilities are prohibited except by 18 permit if: 19 1. There are no alternatives for storm water treatment outside the bluff impact zone 20 on the subject site; 21 2. The site generating runoff is designed so that the amount of runoff reaching the 22 bluff impact zone is reduced to the greatest extent practicable; 23 3. The construction and operation of the facility does not affect slope stability on 24 the subject property or adjacent properties; and 25 4. Mitigation based on the best available engineering and geological practices is 26 required and applied to eliminate or minimize the risk of slope failure. 27 b. In the water quality impact zone, development that creates new impervious surface, as 28 allowed by exemption in section 117 148(1) (exemptions), or fully reconstructs existing 29 impervious surface of more than 10,000 square feet requires a storm water permit or 30 approved storm water plan. Multipurpose trails and sidewalks are exempt if there is 31 down gradient vegetation or a filter strip that is at least five feet wide. 32 c. In all other areas, storm water runoff must be directed away from the bluff impact 33 zones or unstable areas. 34 (5) Development on steep slopes. Construction of structures, impervious surfaces, land alteration, 35 vegetation removal, or other construction activities are allowed on steep slopes if: 36 a. The development can be accomplished without increasing erosion or storm water 37 runoff; 38 b. The soil types and geology are suitable for the proposed development; and 39 •c. Vegetation is managed according to the requirements of section 117 148(i) (vegetatie- 40 management). 41 (6) Conditions of land alteration permit approval. 42 a. Temporary and permanent erosion and sediment control measures retain sediment 43 onsite consistent with best management practices in the Minnesota Stormwater 44 Manual; 45 b. Natural site topography, soil, and vegetation conditions are used to control runoff and 46 reduce erosion and sedimentation; 47 c. Construction activity is phased when possible; 48 d. All erosion and sediment controls are installed before starting any land disturbance 49 activity; Page 113 of 160