ITEM 2.1_attachmentMain Office:
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1 1akanson 3601 Thurston Avenue, Anoka, MN 55303
Anderson Phone: 763/427-5860 Fax: 763/427-0520 4u
I-Itiwww.haa-ine.com
MEMORANDUM
TO: Honorable Mayor and City Council
CC: Lori Johnson, City Administrator
Tami Loff, City Clerk
Dan Licht, AICP, City Planner
Andy MacArthur, City Attorney
Ronald Wagner, P.E. City Engineer
Josh O'Neill, Minnesota Medical Solutions
Welsh Construction
Landform
FROM: Ronald Wagner, P.E. City Engineer
Brent Larson, P.E., Assistant City Engineer
DATE: June 27, 2015 (Revised 7/16/15)
RE: Minnesota Medical Solutions — Development Application/Preliminary Submittal
Review
We have reviewed the Development Application/Preliminary Submittal, dated 6/23/15, for the above
referenced subdivision and we would offer the following comments:
A geotechnical report with soil boring with the water table elevations shown shall be
provided. Per Landform responses received 7/16/15 — Geotechnical report will be
forthcoming.
a. A Septic report shall also be submitted for the 2 proposed septic field areas.
2. Stormwater calculations shall be submitted. Ponds show no outlets therefore they shall be
designed for back-to-back 100 year storm events. The proposed ponds appear large and deep
and may protrude into the water table. Elevations below the water table cannot be used for
pond storage. We have received and reviewed the storm water calculations and narrative
received with the Landform responses dated 7/16/15 and offer the following comments:
a. Stormwater report is missing the Engineer's signature.
b. All site runoff is being directed to the onsite ponds. The ponds appear to be
sufficiently sized to retain back-to-back 100 year storms therefore all City of Otsego
and MPCA requirements for rate control and water quality volume control are being
met.
c. Ponds appear to accommodate for ultimate build out of the site.
d. There is an existing culvert under Jalger Avenue that should have the size identified
but this outlet is not proposed to be used.
e. See comments regarding the grading plan in Comment #6.
f. Ground water elevation shall be verified. The bottom of the pond elevation is at 951.0.
Any volume below the ground water elevation cannot be used.
The pavement section should be based on the soil boring and a geotechnical engineer's
recommendation. Per Landform responses received 7/16/15 — Geotechnical report will be
forthcoming.
4. The entry point to the parking lot appears to be too near the Jalger Aveue and 77th Street
Intersection. Per Landform responses received 7/16/15 — Please indicate the distance a
parking lot needs to be from an intersection.
a. The driveway shall be set back a minimum of 200' from the intersection.
5. Stormwater from the parking lot shall be routed to catch basins and enter the ponds via
stormwater pipes at the NWL elevation. Per Landform responses received 7/16/15 — catch
basins and pipe will be provided.
6. No grades on the parking lot or curb are depicted. Per Landform responses received 7/16/15 —
Grades will be provided for the building permit submittal.
a. Label the back-to-back 100 yr HWL elevation of the ponds.
b. Label the slopes along the ponds. They appear to be 3:1 slopes. Typically a 4:1
maximum is allow above the NVVL with a 10:1 safety bench and up to 3:1 slopes
below the NWL. Because this pond and the site is completely contained and a fence is
to surround the entire site, 3:1 slopes are acceptable.
7 it is di +lt to read the osian eontrol plan shee*. A frill sized set of plans has been received
and is legible.
8. In addition to the above comments the following Existing Conditions information shall be
provided for all preliminary plat submittals:
I. Boundary lines to include bearings, distances, curve data, and total acreage of
proposed plat, clearly indicated.
2. Existing zoning classifications for land in and abutting the subdivision.
3. Total area of the proposed plat.
4. Show location, names, widths of existing streets, buildings, etc within 150'.
5. Location, size, and elevations of existing sewers, watermain, culverts, and
other underground facilities within 150'.
6. Boundary lines of adjoining unsubdivided or subdivided land, identified by
name and ownership within 150'.
7. 2 foot contours. Water courses, marshes, wooded areas, rock outcrops, power
transmission poles and lines. USES datum shall be used for all topographic
mapping.
8. Subsurface conditions far subdivisions utilizing individual water and sewer
systems. Locations and results of soil borings, percolation tests, etc.
9. 100 year flood elevations.
10. Statement certifying the environmental condition of the site including the
presence of any hazardous substance as defined in Minnesota Statutes 11.58.02,
Subd 8.
Hal(anson
Anderson
9. The development shall be platted with 40' of right-of-way along Jalger Avenue and 77th Street
and drainage and utility easements over the ponds.
Summary and/or Recommendation
W reeemmendr-evisinga fe „h„ +ting pr-ier- to ft*- her feview, Re recommend approval of the
preliminary submittal contingent upon the above comments being addressed.
1AIHakanson
Anderson