Loose Ended Levees? Levee Certification Process and Emergency Action Plan - A Case Study in Phoenix, Arizona

摘要

This presentation will showcase a case study of a hanging levee in the City of Phoenix, Arizona. This hanging levee was built by the City and ties into the County's Skunk Creek 1 Levee (SK1), designed and built by the U.S. Army Corps' of Engineers. It will also discuss the accreditation process for each agency's Levees. Subsequent to the accreditation of the SK1 Levee, an Emergency Action Plan (EAP) was prepared by the Flood Control District of Maricopa County. This EAP, which covers both the SK1 Levee and the City's portion of the levee, will also be discussed briefly in this presentation. Complicating the City's PAL Agreement response to FEMA for the City's Levee, discussions regarding the SK1 Levee re-certification has begun between FEMA and the US Army Corps' of Engineers. Levees may pose a risk of failure by overtopping or breaching and cause flooding. Through the National Flood Insurance Program (NFIP), the Federal Emergency Management Agency (FEMA) requires that communities with levees must certify that per 44 CFR 65.10 The City submitted their levee certification package to FEMA, and is awaiting accreditation before a revised Flood Insurance Rate Map (FIRM) is printed. Rather than tie into high ground on the upstream end, the City levee ties into a levee operated by the Flood Control District of Maricopa County. The downstream levee end of the City levee is "loose ended" or "hanging" and does not tie into either the Skunk Creek channel banks or another levee. Emergency Action Plans (EAP) are now (as of 2016) required for all newly accredited Levees within any jurisdiction. An EAP was prepared for the Skunk Creek 1 Levee (SK1). The SK1 Emergency Action Plan (EAP) was prepared to coordinate monitoring of storm, river stage levels, and levee conditions with local emergency management and response activities in the event of an emergency. The EAP includes analysis of the hanging levee portion operated by the City.