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Res. 7885, Considering Stormwater Infiltration Program Appeals in Area E Page 2 pronounced impact on groundwater elevations as evidenced by comparing groundwater elevations in late spring/early summer (very high) to those in September (considerably lower). Infiltration from the basin will “mound” or be contained in the soil in the immediate vicinity of the basin and will not impact a structure located 30 feet away. • Based on the groundwater elevation data available, there is 3 feet of separation between the bottom of the basin and the ground water elevation as required. • The length of the basin will be shortened to remain outside the tree dripline, whereby significantly reducing the risk of any negative impact on the tree. • A proposed second driveway curb cut is not allowed per City Code. In addition, driving over vertical curbing is discouraged. • The proposed feature length is 40 feet. The total boulevard length between the driveway and north property line is 56 feet. City staff and the S/U Committee recommend denying this appeal. Staff has spoken with Mr. Thompson about his concerns and he seems OK with the basin as planned. 5140 Brighton Lane (Terrance Pajerski) – SIP#53 The property owner is appealing for the following reasons: 1. worried about water in basement (surface runoff and ground water); and 2. oak tree near property line • There is no evidence that infiltration into the ground from the basin storage will cause a change in groundwater elevation. [See additional information under SIP#34] • Based on the groundwater elevation data available, there is 3 feet of separation between the bottom of the basin and the ground water elevation as required. • The north cross-section at this property indicates a slight grade away from the street. The infiltration basin will be constructed to drain back towards the street, and if necessary, a slight berm will be constructed on the backside of the basin to ensure this. • The length of the basin will be shortened to remain essentially outside the tree dripline, whereby significantly reducing the risk of any negative impact on the adjacent tree. • The proposed infiltration basin length is 48 feet. The total boulevard length between the driveway and north property line is 60 feet. City staff and the S/U Committee recommend denying this appeal. Staff has spoken with Mr. Pajerski about his concerns. 5141 Brighton Lane (Keith and Louise Fester) – SIP#54 The property owner is appealing for the following reasons: 1. insufficient stormwater runoff to basin (A5); 2. access to storage shed (B4); and 3. worried about water in basement. • The total drainage area to the proposed basin is 0.33 acres will provide a sufficient amount of runoff. • A proposed second driveway curb cut is not allowed per City Code. Driving over vertical curbing is discouraged. • There is no evidence that infiltration into the ground from the basin storage will cause a change in groundwater elevation. [See additional information under SIP#34] • Based on the groundwater elevation data available, there is 3 feet of separation between the bottom of the basin and the ground water elevation as required. • The proposed infiltration basin length is about 35 feet (previously 42). The total boulevard length between the driveway and north property line is 66 feet. City staff and the S/U Committee recommend denying this appeal. Staff met with Mr. and Mrs. Fester on-site to hear concerns and determine basin length to accommodate access to outbuilding. Mr. and Mrs. Fester are OK with the basin as planned.