Ordinance No. 20415 - Laserfiche WebLink

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floodplain, the design of the replacement bridges must satisfy the regulations set forth in the National Flood Insurance Program (NFIP). The NFIP requires that any modifications that cause a rise in the Base Flood Elevations (BFEs, which corresponds to water surface elevations associated with the 100-year flood event) must be approved by FEMA. Two pier location scenarios are currently under consideration (Proposed Option A and Proposed Option B, see written statement page 9). Based on preliminary modeling, Option A would result in an increase of 0.02 feet over existing conditions for the 100-year flood event. For the Environmental Assessment, 'the hydraulic conditions of the 1-5 Willamette Bridge Project were analyzed using the U.S. Army Corp of Engineers' HEC-RAS model. Natural, existing and proposed conditions (with pier locations Options A and B) were modeled. Conservative assumptions regarding pier size were used for this modeling. Refined design of the concepts and further hydraulic analysis will allow confirmation that the proposed project will result in no rise of the base flood elevation. Option B would result in a decrease of 0.54 feet for the 100-year flood event, which is consistent with the no-rise standard and consistent with this goal. While Option A shows an increase of 0.02, which does not meet the no-rise requirement, this is not a detailed analysis and modeling will be run again when the design is refined for the permitting process in order to meet the no-rise requirement. A FEMA "no-rise" certification will be obtained from the City of Eugene for any construction or structures within floodways/special flood hazard areas that are outside of rights-of-\vay, within Eugene. In addition, the applicant states that the no-rise condition is also a requirement of ODOT for any bridge replacement project. Other hazards, such as earthquakes and severe winter storms can be mitigated at the time of development based on accepted building codes and building techniques. As previously stated, specific construction and operational details will be appropriately addressed during local permitting processes, subject to applicable approval criteria and related standards. Therefore, in the context of a plan amendment, the preliminary no-rise data, the landslide information, and findings above, the proposed plan amendments are consistent with Statewide Planning Goal 7. Goal 8 - Recreational Needs: To satisfy the recreational needs of the citizens of the state and visitors and, where appropriate, to provide for the siting of necessary recreational facilities including destination resorts. Goal 8 ensures the provision of recreational facilities to Oregon citizens and is primarily concerned with the provision of those facilities in non-urban areas of the state. East Alton Baker Park is located to the east and west of 1-5 right-of-way, which includes recreation, bicycle and pedestrian paths and the canoe canal (utilized by kayakers). The portion of the park that is west of 1-5 in Eugene is now called the Whilamut Natural Area and the portion of the park east of 1-5 in Springfield is called the Eastgate Woodlands of the Whilamut Natural Area (abbreviated here as Eastgate Woodlands) and these areas will be referred to as such for the remainder 0 f these findings unless otherwise indicated. The demolition and construction of the bridges will take place within the 1-5 right-of-way, which is not part of the park; therefore the replacement bridges will not remove or increase recreational opportunities at the park. However, removal of the detour bridge will include Exhibit A - Findings Page 18