HomeMy WebLinkAbout4B Maple Park Shore Acres 2nd Addn Addition Preplat
Phone 952.447.9800 / Fax 952.447.4245 / www.cityofpriorlake.com
4646 Dakota Street SE
Prior Lake, MN 55372
PLANNING COMMISSION AGENDA REPORT
MEETING DATE: FEBRUARY 6, 2017
AGENDA #: 5B
PREPARED BY: JEFF MATZKE, PLANNER
PUBLIC HEARING: YES
AGENDA ITEM:
AFTER CONDUCTING A PUBLIC HEARING, CONSIDER RECOMMENDING
APPROVAL OF THE MAPLE PARK SHORE ACRES 2ND ADDITION
COMBINED PRELIMINARY AND FINAL PLAT
DISCUSSION: Introduction
Greenwood Design Build LLC, the property owner, has applied for approval of
a Combined Preliminary and Final Plat to be known as Maple Park Shore Acres
2nd Addition to be developed as a 3 lot, low density residential subdivision. The
subject property is located east of County Highway 21 and south of Lords Street.
History
A single family dwelling is currently located on the site. In 1924, the Scott
County Board approved the final plat of the Subdivision of Outlot A of Maple
Park Shore Acres which included 12 lots. These lots are all included in the
single parcel of record that is requested for this subdivision.
The Planning Commission opened the public hearing for this item on January
17, 2017 and continued the hearing to Feburary 6th instructing the developer to
continue to revise the plans according to the stormwater and grading comments
by City Staff.
Current Circumstances
The current proposal calls for a 3 lot single family subdivision of the site.
The following paragraphs outline the physical characteristics of the existing site,
the Comprehensive Plan and zoning designations, and a description of some of
the specifics of the site.
PHYSICAL SITE CHARACTERISTICS:
Total Site Area: The total development site area consists of 1.50 acres.
Topography: This site has relatively level topography, with elevations ranging
from 948’ MSL along the southern boundary to 926’ MSL at the wetland edge.
Wetlands: A wetland does exist onsite. No impacts to this wetland are
proposed. The delineated edge of the wetland was approved in 2016.
Access: Access to the site is currently from Edinborough Avenue (a private
road). This access point will be maintained with the plat.
2030 Comprehensive Plan Designation: This property is designated for Low
Density Residential uses on the 2030 Comprehensive Plan Land Use Map.
Zoning: The site is presently zoned R-1 Low Density Residential.
PROPOSED PLAN
Lots: The plan calls for 3 lots to be constructed of single family housing styles.
The lot sizes range in size from approximately 12,000 square feet to 19,300
square feet. All lots meet the minimum dimensional requirements.
Setbacks: The typical residential required setbacks of 25-foot front and rear,
10-foot side yards, and 30 feet from the wetland are proposed.
Parks / Trails: No park or trails are proposed. Parkland dedication will be
satisfied through a cash-in-lieu payment to the City Park Fund with Final Plat
approval.
Sanitary Sewer / Water Mains: Sanitary sewer and water mains were installed
in the Edinborough right-of-way in the 1970s. Individual lateral utility
connections will be made for Lots 2 and 3 at the time of building permits.
Grading / Storm water: The City has some comments related to grading and
storm water on the project. The City has meet and discussed these comments
with the developer.
Fees and Assessments: This development will be subject to the standard
development fees including park dedication, and trunk street and utility service
charges.
Conclusion
The developer has made revisions to the storm water and grading plans since
the last meeting and while some minor revisions stil remain to be addressed,
City Staff recommends the item be recommended for approval and more on to
review by the City Council.
ISSUES: The Developer has discussed issues related to the design of the plat including
storm water and grading regulations. As noted in the attached staff
memorandum from the Engineering/Public Works Department, the developer
must refine the plans to assure compliance with the Public Work Design Manual
requirements and City Zoning Ordinance. It does not appear that these
comments will drastically affect the design of the plat.
ALTERNATIVES: 1. Motion and a second to recommend approval of the Combined Preliminary
Plat and Final for Maple Park Shore Acres 2nd Addition subject to the
comments listed in the February 2, 2017 Engineering/Public Works
memorandum, or others that may be added or modified by the Commission.
2. Motion and a second to recommend denial of the preliminary plat request
based upon findings of fact.
3. Motion and a second to table this item to a future Planning Commission
meeting and provide the applicant with direction on the issues that have
been discussed.
RECOMMENDED
MOTION:
Alternative #1
ATTACHMENTS: 1. Location Map
2. Development Plans dated January 23, 2017
3. Engineering/Public Works Dept. Memorandum dated February 2, 2017
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MAPLE PARK SHORE ACRES
15242 EDINBOROUGH AVE NE, PRIOR LAKE, MN
5555 WEST 78TH ST., SUITE L, EDINA, MN 55439
GREENWOOD DESIGN BUILD, LLC
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Phone 952.447.9800 / Fax 952.447.4245 / www.cityofpriorlake.com
Memo
Date: February 3, 2017
To: Community and Economic Development Department
From: Engineering Department – Nick Monserud, Project Engineer
Public Works Department – Pete Young, Water Resources Engineer
Subject: Maple Park Shore Acres (Project #DEV16-000002)
The Engineering Department and Public Works/Natural Resources Department have reviewed
the final plat for the subject project with a plan date of January 23, 2017. The plans were
reviewed for consistency with City Ordinance and Standards detailed in the City of Prior Lake
Public Works Design Manual. The following list details deviations from standards or requests for
additional information that must be reconciled prior to project approval. The applicant or its
representatives are invited to contact the engineering department with any questions or
clarifications at 952-447-9830. Comments highlighted in bold text are of particular concern:
General
1. The final plat plans should follow the requirements of the Public Works Design Manual
(PWDM), specifically the comments below.
2. A digital copy of the plans in pdf or tif format is required prior to construction. All
drawings shall use the Scott County Coordinate System.
3. The drainage and utility easement shall be shown for the area where the outlet structure is
to be installed on the survey and plan sheets. Include easement number. Verify that the
proposed outlet structure is within the easement. If it is not, all work will have to occur
within the drainage and utility easement.
Grading
1. Slopes along the South side and West side of Lot 2 are at 2.5:1. No slopes shall be
steeper than 4:1 in maintained areas and 3:1 adjacent to natural resources.
2. Revise note #3 under the City of Prior Lake Removal Notes on sheet C1.0 to “Any
construction damage to Edinborough Avenue shall be repaired and replaced at the
Developers expense.”
3. Show grading around pond outlet structure on grading plan, submerged culvert pipe, and
flared end section.
4. Grading the lots along Edinborough Avenue to drain to the existing roadway will
negatively impact off-site properties and the flowpath for the runoff may not be able to
handle an increase in runoff rate/volume. Due to the potential impacts to neighboring
properties, adding runoff to this area without adequate controls will not be allowed. The
City strongly recommends curb and gutter along Edinborough Avenue in lieu of the
proposed swale through driveways and front yards for the following reasons:
a. Swale will need to be at a minimum centered in the drainage and utility easement
to protect the private roadway. A driveway detail showing plan and profile
sections will need to be provided and approved.
b. No landscaping or snow storage will be allowed in the swale area to maintain
drainage.
c. Edinborough Avenue is a private road and any stormwater runoff directed to the
edge of the pavement will undermine the street. Since it is a private street all
repairs are at the resident’s expense.
d. Curb and gutter will add to the curb appeal of the new houses and will better
protect the existing road.
e. Driveways will steepen and have a dip that will be undesirable to home owners
and possibly be difficult to navigate for low profile vehicles or trailers.
f. Spot elevations need to be shown for ditch swale through driveways.
Hydrology and Storm Sewer
1. Provide pond outlet structure detail showing elevations that correspond to HydroCAD
modeling (weir wall, orifice, etc.).
2. Filtration is preferable to a fully infiltrating design for the required stormwater basin.
Stormwater BMP design must meet the requirements of the Minnesota Stormwater
Manual for bioretention. Refer to this website for details:
https://stormwater.pca.state.mn.us/index.php?title=Design_criteria_for_bioretention
Provide the following additional details for the basin:
a. A separation distance of 3 feet is required between the bottom of the bioretention
practice and the elevation of the seasonally high water table. Provide soil boring.
b. Show contours to better define the EOF. TRM is noted but an area lower than the
surrounding contour still needs to be shown to ensure that water will flow through
at the EOF point.
3. HydroCAD revisions:
a. Pond EXP: EXISTING POND – Device #1 Primary outlet should be 15” not 8”.
b. OFFSITE 2: Tc of 49min seems excessive for drainage of a road. Tc should be
equal to 6 min or calculated for pavement. OFFSITE 2 area includes a portion that
drains directly to Prior Lake; please revise to reflect actual conditions. Lastly,
please calculate actual impervious area rather than assume 1/3 acre lots at 30%
impervious area for a road.
c. OFFSITE 1: Area includes a portion that drains directly to Prior Lake; please
revise to reflect actual conditions (update drainage divides).
d. FILTRATION BASIN 1: Show exfiltration with assumed filtration rate over the
bottom surface area of the basin. This should be a secondary outlet.
e. Volume calculations shall show a calculation of the surface area of the bottom
contour required to infiltrate the required volume in 48hrs. Assuming infiltration
in the pond slopes is not acceptable with a filtration design.
Wetlands
1. Wetland buffer reestablishment detail calls for “Netless Cat. 4 coconut erosion control
blanket per MnDOT Specs”. There are no Category 4 net free erosion control blankets;
all MnDOT-approved net free blankets are category 0 or 00. These blankets should
suffice in this location due to the lack of concentrated flow. Natural net erosion control
blanket or hydromuch could also be specified for this area.
2. Additional wetland buffer monuments are needed to define the buffer edge:
a. Lot 1: mid-point of lot, inflection point (1)
b. Lot 2: two inflection points (2)
c. Lot 3: inflection point near basin, southernmost inflection point (2)
SWPPP
1. The project is located in a shoreland zone and will result in land disturbance of more than
10,000 square feet. A SWPPP that meets the requirements of the NPDES Construction
Stormwater Permit must be reviewed and approved before a grading permit will be issued
for the site. Full SWPPP review will occur after updated plans are submitted.