HomeMy WebLinkAboutRE: Bonestroo review Otto G.Bones[roo,PE Howard A.Sznford,PE. Michael P Rau,PE. Mark D.Wallis,PE.
Bonestroo Robert W Rosene PE' Keith A Gordon,PE Philip J Pyne,PE Miles B Jensen,PE.
Joseph C.Anderlik.PE Robert R.Pfefferle.PE. Agnes M.Ring,AJCP L.Phillip Gravel III,PE.
Marvin L.Sorvala,PE. Richard W Fosrer,PE Thomas W Pe[erson,PE. Karen L.Wiemeri,PE.
Rosene Richard E Turner PE David O Losko[z PE Michael C Lyn[h PE Gzry D Krisrofitz PE.
� Anderlik & T�homaR E NoyesEPE Jerbry ACBourd n,PEA Jerry DRPertz ch�PE KeithdR Yappr PE
Robert G.SchunichL PE. Mark A.Hanson,PE. Kenne[h P Anderson.PE. Douglas J.8enoiC PE.
Associ�tes Susan M Eberlin CPA Michael T Rautmann PE Mark R Rolfs PE Shawn D Gus[afson,PE.
*Senior Consultant Ted K.Field.PE. Mark A.Seip,PE Cecilio Olivier,PE.
Thomas R.Anderson.AJA. Gary W Morien,PE. Charles A.Erickson
Engineers & Architects Donald C BurgardL P.E Daniel J.Edgerton.P.E. Leo M Pawelsky
Thomas E.Angus.PE. Allan Rick Schmidt PE. Harlan M.Olson
Ismael Martinez.PE. Philip J.Caswell.PE. James F Engelhardt
March 16, 1994
_;°`�___
��y I!�
� ���./�._....__..
Ms. Jeanne A. Mabusth,
Building and Zoning Administrator
City of Orono
Pnst Office Box 66
Crystal Bay, Minnesota 55323 ���'R �' 8 v
Re: Vergeyle Residence
File No. 139-1909 � ��> ,�.��i-7� � ��'�:� _i, ��'?�-�'�
1 � �
Dear Jeanne,
We have reviewed the geotechnical evaluation and grading, drainage and erosion control plan
prepared by Schoell & Madson, Inc. for the Vergeyle residence. The property is located on
Green Trees Road, overlooking Tanager Lake. We have several comments in regards to
engineering matters.
The two 4-foot tall retaining walls are proposed to control up to 8-feet of fill to be placed on
the existing slope. The wall as shown, and noted on this plan, is acceptable from an engineering
standpoint. However, more information must be provided to identify the specific block, type
of fill and the type of tie-back restraints to be used. Each block manufacturer has specific
design charts that may be used depending on the type of fill and loading conditions. The
loading condition for this wall must be a 3:1 backslope. The two walls must be placed at least
as far apart as they are tall (l:l) or a surcharge loading must be used.
The proposed :oof�.;ains, catch basins and 1�J-inch p�pes 1_ead?ng tr• thP hottprp nf rhe s�ope are
a good attempt to prevent slope erosion. However, the 10-inch pipe will have an outlet velocity
of approximately 25 feet per second which will be difficult to control at the bottom. The pipe
may not be necessary if a good ground cover is established. The roof could be drained by
downspouts with overland flow. We feel this method has less potential for erosion.
We do not recommend or approve of gravity type retaining walls, such as the limestone boulder
wall proposed by the builder, due to the difficulty in determining their effectiveness.
Please contact me at this office if you have any questions regarding this matter.
Yours very truly,
BONESTROO, ROSENE, ANDERLIK & ASSOCIATES, INC.
i��Tl�'� �-
Shawn D. Gustafson, P.E.
2335 West Highway 3G • St. Paul, MN 55113 • G1�-63G-4600