Laserfiche WebLink
r <br />SEP 11 2 1&:33 FR BPRR ENGINEERING <br />BARR <br />952 832 2601 TO 92494616 P.02/03 <br />Barr Engineering Company <br />4700 West 77th Street • Minneapoiis, MN 55435-4803 <br />Phone: 952-832-2600 • Fax: 952-832-2601 <br />Minneapoiis. MN • Hibbing. MN • Duluth. MN • Ann Arbor, Mi • Jefferson City. MO <br />%r <br />September 11,2000 <br />Mr. Paul Weinberger <br />City of Oronc <br />2750 Kelley Parkway <br />PO Box 66 <br />Crystal Bay. MN 55323 <br />Re: Brenahell Homes Development Proposal <br />Dear Mr. Weinbergen <br />At the request of Mr. Gary Welsh and other concerned citizens of Orono, Barr Enginwnng Company <br />has reviewed the revised development plans received today in suppon of the ?ropo5ed Brensneu <br />Hones subdivision at 1181 Wildhurst Trail in Orono. We are providing coi;anents for your <br />consideration in evaluating the proposed subdivision at your September 11.2(W0 city council <br />meeting. Based on our latest review, we continue to have concerns regarding the steep slopes ana <br />wetland losses. <br />Steep Slopee and Eroelon Concerns <br />The revised development plans include a reconfiguration of the lot line between Lots 2 and 3 and a <br />minor reduction in the cul-de-sac length as recommended by city staff. However, the plws do not <br />adequately protect the slopes and ravine from erosion due to concentrated runoff from the backs and <br />sides of the homes. Unfortunately, approximately onc-half of the house pad on Lot 2 md <br />approximately one-sixth of the house pad on Lot 3 lie within areas defined as sleep slopes <br />steeper than 12%). The current plans have not altered the drainage to ensure that concerted runoff <br />does not cause erosion in the south ravine and on the steep slopes leading to Wildhurst Trail. <br />The south stormwater pond is also planned for construction within the south ravine in arcM c^ntly <br />containing slopes steeper ^ 18 percent. The constrociion of the south pond would requue *c <br />removal of numerous!«.!;- maple trees which are currently providing stability in the ravme. The <br />steep slopes on LoU 2 and 3 are cuirenily protected from erosion by: <br />1 The full tree and siirub canopy which intercepts rainfall, maintains a more perraeabk soil <br />structure and wicks away moisture from within the soUs by cvapotranspiraiion, and <br />2. The natural surface roue wss and small depressional areas in the upstream drmnage area slows <br />any runoff that docs occur so runoff within the ravine is spread out and maintained at lower <br />rates. <br />As the city staff recommended at our meeting on September 6,2000, a conservation easement should <br />be provided over the steeper slopes on Lots 2 and 3 to protect the existing veget^ve cover and <br />ground elevations. The pond would also create a new slope into the ravine which would be sttcper <br />than 20 percent. Constructing the pond within a flatter area would eliminate smaller trees and create <br />less of an erosion concern.