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Ms.Kathy Pollock May 21,2015 Page 2 • Reviewed available topographic information for 900, 950, and 990 North Shore Drive before and after the residence on the 990 property was built During this visit, I also listened to your description of your drainage problems since the residence on the 990 property was built. In particular,you described and showed me substantiating photographs of: 1. Channelized flows coursing from the 990 property through a forested portion east of your house, running across your onsite sewage treatment drain-field area, eroding an area not far from your east patio door, and flowing north across the lawn where your septic tanks and drain- field pump station are located. Photo 6,which you provided to me, shows the channel of water you described. Photo 7 documents conditions after the runoff subsided. To your recollection, in the 29 years that you have lived at 950 North Shore Drive,you have never seen channelized flows running through that area of your property, and the erosion was not present until the residence on the 990 property was built. 2. Channelized flows coursing from the 990 property through another forested portion of your property(to the west of your house), across your driveway, onto your lawn, and across your garden along the north side.You provided me with Photos 8, 9, and 10, showing the channelized flows in action and Photos 11 through 16, showing the aftermath of the channelized flows.In the 29 years that you have lived at 950 North Shore Drive,you do not recall seeing the magnitude of channelized flows that now run through that area of your property(nor the ensuing damage) prior to the residence on the 990 property being built. 3. Channelized flows coursing from the driveway on the 990 property onto the east gutter of North Shore Drive,then down your driveway, across your yard, and into your garden area along the north side.The arrows on Photo 17 show the drainage pattern of flows passing down the driveway of the 990 property onto North Shore Drive and then down your driveway. Photo 9 shows the actual flow and Photos 11 through 14 show deposits from the 990 property(eroded road base and stones) in your yard. Photos 15 and 16 show the deposition of material in the garden on the north side of your property, as well as where woodchips were flushed from that area.In the 29 years that you have lived at 950 North Shore Drive,you do not recall observing the magnitude of channelized flows that now occur since the residence on the 990 property was built. 4. A history of ongoing drainage problems relative to the way flows are managed on North Shore Drive, and how the development of the 990 property has exacerbated those problems.In particular,you described that in 1993 Hennepin County placed a bituminous bump feature at the end of your driveway to keep flows from the then upgraded North Shore Drive from flowing down your driveway. This bump caused other problems for cars entering or exiting your driveway including cars bottoming-out, icing issues, and safe access when turning onto North Shore Drive.As a result of those problems, Hennepin County removed this bump in 1995. In 1996, Hennepin County installed curb and gutter on North Shore Drive from the crest of the roadway hill (south of your property)to the north along your property. The east roadway ditch on your property was filled as part of the 1996 curb and gutter and roadway improvement project.The fill that was needed to match into the increased roadway elevation essentially removed the ditch and created a sloped shoulder that now largely drains into your yard rather than draining where the ditch was.The increased runoff from the 990 property that flows onto North Shore Drive,freely flows down your driveway and the road shoulder into your yard as there is no ditch to capture or convey the flows to the north.The increased runoff volume and flow velocity from the 990 property combined with the runoff from North Shore Drive has P:\Mpls\23 MN\27\23271432 Drainage Issues-950 N Shore Dr\WorkFiles\Report