memo re site visit - Laserfiche WebLink

Home Browse Search

t Memorandum �Bonestroo 2335 Highway 36 W To: Lyle Oman Project: 2690 Fox Street Dace: 11-14-07 st.Paui,MN 55113 From: Lance Hoff Client: City of Orono Tel 651-636-4600 Fax 651-636-1311 Re: 11-12-07 Slte Vislt File No: 139Gen �W,bonestroo.com Plat#139-A11097 Background: I met with Steve Moore at his site on Monday the 12`h at his request. He had previously walked the watershed and spoken with neighbors and felt that the SWMP and associated modeling may have overestimated the amount of area/runoff routed through his property. He felt this may have also led to an over-design of the proposed pipe and berm design on his property. I walked the area with him and he pointed out what he has observed and we discussed his prior conversations he has had with his neighbors. The list below summarizes the main points from that site visit: 1. The existing 8" draintile that appears to convey the majority of the upstream base flows has been routed around the house using 8" PVC and connected to the existing on-site structure. Base flow discharging from the new 8" PVC draintile was observed in the existing on-site structure during the site visit. 2. The upstream watershed routed to the site is restricted by the small(�12") existing and partially clogged CMP running under Old Chrystal Bay road. This culvert is located approximately 200' north of the Old Chrystal Bay Road and Fox Street intersection. 3. Neighbor observations indicate that a limited amount of flow typically discharges overland to the Moore property. Steve mentioned that even with the large amount of rainfall the region received in October, the draintile appeared to convey most of the flow with very little runoff conveyed overland across his property. 4. The 24" RCP culvert crossing under Old Chrystal Bay Road located approximately 1,200' north of the Old Chrystal Bay Road and Fox Street intersection drains around the site and does not contribute runoff to the site. 5. There is an existing 5" clay tile line located in the NE corner of the property at the low point that does not appear to be conveying flows. Comments: The following comments correspond to the main points listed above. 1. The 8" PVC tile connection from the existing 8" tile line to the existing structure appears to have been properly constructed and is conveying upstream flows adequately. The upstream low area that the draintile services also appeared to be sufficiently drained. 2. I double checked the watershed areas and routing shown in the City's LSWMP using 2' contour maps. The drainage areas and routing are shown correctly in the LSWMP.