Review Sketch Plan for Property at 6080 Highway 10 NW (Project No. 18-163)

The purpose of this case is to review a Sketch Plan for a subdivision of the property located at 6080 Highway 10 NW (the "Subject Property").  The Subject Property is currently zoned both R-1 Residential (MUSA) and E-1 Employment.  The Sketch Plan shows fourteen (14) detached villa lots plus three (3) outlots that will contain the storm water pond, infiltration basin, and trail (part of the Mississippi River Trail).  Based on the proposed Sketch Plan, which is most closely associated with the R-2 Residential (Medium Density) District, a Comprehensive Plan Amendment and a Zoning Amendment will be required.  This review is being based on R-2 Residential District standards.

It should be noted that in 2014-2015, the Subject Property did receive Final Plat approval for a seven (7) lot single family residential subdivision.  At that time, work began in terms of tree removal and grading.  However, additional soil borings were completed that did identify buried debris above fifteen (15) feet below the surface.  Due to the costs associated with removing the buried debris, the project was never completed.  Village Bank (the "Applicant") is now seeking grant funds to assist with the debris removal. 

Natural Area(s)
The City's Natural Resources Inventory (NRI) does identify an altered/non-native deciduous forest on the Subject Property.  This would not consistute a high value natural area and some of the wooded area had previously been removed (per the now defunct previous subdivision).  The remainder of the Subject Property is classified as 'urban with vegetative cover' or 'urban with little vegetative cover' per the Minnesota Land Cover Classification System (MLCCS).

Critical River Overlay District
Only the very southwestern corner of the Subject Property falls within the Critical River Overlay District.  None of the proposed residential lots fall within this part of the Subject Property.  Outlot A, which does lie within the overlay district, does meet the minimum lot size of 20,000 square feet for a riparian parcel.  There are no buildings proposed within the overlay district.

Floodplains
Portions of the Subject Property fall within the Floodway and Flood Fringe floodplain boundaries.  The Floodway area is isolated directly adjacent to the Mississippi River and does not appear to be impacted at all by the proposed subdivision.  All three (3) outlots, plus the proposed lots on Blocks 2 and 3, all lie within or at least contain portions of the Flood Fringe designation.  Fill can be used to elevate structures in the Flood Fringe to ensure that the lowest floor elevation is at or above the Regulatory Flood Protection Elevation (RFPE).  Per the Grading Plan, it appears that the lowest floor of all of these buildings will comply with the RFPE standard, but an Elevation Certificate, prepared by a licensed surveyor, will be needed for each of the lots in Blocks 2 and 3 to verify compliance.

Both the storm water pond and infiltration basin are proposed within the Flood Fringe boundary.  Staff has placed an inquiry to the MN DNR to better understand if that is allowable within that portion of the floodplain.

Density Transitioning
Due to the adjacent, existing residential neighborhood, Density Transitioning will be required along the western boundary of the Subject Property.  If landscaping is used to satisfy this requirement, the vegetative buffer will need to be a minimum of twenty-five (25) feet in width and be held in common ownership.  Within this buffer area, for every 100 feet of property boundary, there shall be two (2) overstory trees, two (2) evergreen trees, and two (2) understory trees and plant sizes shall be a minimum of 2.5 inch caliper, six (6) feet in height, and 1.5 inch caliper, respectively.

Tree Preservation
A Tree Inventory and Preservation Plan is required but has not been received yet.  Any residential development is required to retain forty percent (40%) of the significant tree Diameter at Breast Height (DBH) inches on site.  If that threshold is exceeded, the reforestation shall be at a ratio of 1.25 inches for every 1 inch removed.  There are exemptions of trees removed due to storm water ponds (and infiltration basins), invasive species, trails and sidewalks.  It does appear that some tree removal will be needed due to the proposed location of the storm water pond and infiltration basin.  It would be preferable to preserve trees nearest the riverbank both for stabilzation purposes as well as aesthetics from the river.

Landscaping
A Landscape Plan is required but has not yet been received.  Based on the R-2 Residential standards, the Canopy Cover Formula would be used to determine the minimum landscaping required.  This formula attempts to take into consideration the overall pervious and impervious area of a project, as well as canopy cover of trees at maturity, to avoid over planting of a site. 

All costs associated with this project are the Applicant's responsibilty.

Provide general feedback on the Sketch Plan as it relates to natural resources.  Note that Staff has prepared a Staff Review Letter addressing items that either are lacking and/or need to be addressed.