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1.5.2 Floodplain Mapping <br /> The Project Team shall perform a delineation of the proposed FEMA flood hazard areas behind <br /> the Willow Creek Levee. The delineation shall be based on the HEC-RAS hydraulic modeling <br /> results (see Task 1.5.1). The Project Team shall incorporate all new and revised hydraulic <br /> modeling results and topographic information to delineate the floodplain boundary on a digital <br /> work map. The mapping shall be consistent with FEMA standards. Floodplain and/or floodway <br /> mapping shall not be performed for the 10-,25-and 50-year events. <br /> 1.5.3 Preparation and Submittal of Deliverables <br /> The Project Team shall prepare and submit to the City and FEMA an updated TSDN that includes <br /> the re-analysis of the interior area for Willow Creek Levee and Willow Creek from Willow Creek <br /> Road upstream to Williamson Valley Road. <br /> TSDN submittals shall include two(2)drafts and three(3)finals. The TSDN will be prepared for <br /> FEMA submittal in accordance with the requirements set forth in Guidelines and Specification for <br /> Flood Hazard Mapping Partners. <br /> 1.6 Waterline Scour Protection and Environmental Permitting <br /> 1.6.1 60%,90%,Final Plan Submittals <br /> Construction plans will be developed based on a site review with City staff,it is anticipated that <br /> the design will include the following: <br /> • Scour protection for the existing three water lines crossing Willow Creek main channel 1000 <br /> feet east of Clearwater Drive dip crossing. <br /> • It is anticipated the scour protection (concrete cutoff wall, gabion mats or articulating <br /> revetment units or combination thereof) will extend approximately 180 feet across the main <br /> channel and 70 feet along the channel to protect the three water lines. <br /> 1.6.2 Opinion of Probable Cost Specifications&Estimates <br /> Construction Special Provisions(CSP)will be provided by JEF to be included in the bid package. <br /> Estimates of construction quantities and costs will be submitted with all submittals and the CSPs <br /> will be submitted at the 90%and Final plan submittals. Project will be based on applicable City or <br /> MAG Specifications. <br /> 1.6.3 Nationwide 404 Environmental Permitting <br /> It is anticipated that the project will be constructed under USACE Nationwide Permit 12: Utility <br /> Line Activities(Nationwide Permit). <br /> 1.6.3.1 Jurisdictional Determination <br /> In support of this Nationwide Permit,JEF will prepare a jurisdictional determination(JD)suitable <br /> for submittal to the US Army Corps of Engineers(USACE). <br /> 1.6.3.2 USACE 404 <br /> JEF will prepare and submit to the USACE a Nationwide Permit. In addition,JEF will attend up <br /> to two(2)meetings with the local US Army Corps of Engineers permitting staff to coordinate <br /> preparation and submittal of a JD,Nationwide Permit,and a pre-construction notification. <br /> 1.6.3.3 Pre-Construction Notification <br /> JEF will prepare a pre-construction notification(PCN)for the US Army Corps of Engineers. The <br /> PCN will be developed based upon the application of the USACE Nationwide Permit. <br /> October 8,2012 <br /> Willow Creek and Willow Creek Tributary Restudy Page 3 of 6 <br />