Mr. Rigel Rucker, the RAMPP Study Manager, began the meeting at 1:30 PM (MT) with a PowerPoint presentation.

Transcription

1 Project Name: Socorro County, NM DFIRM and FIS Updates Attendees: Meeting: Analysis Over-The-Shoulder Review Meeting Agenda Items Date: December 9, 2010 Place: City of Socorro, 111 School of Mines Road, Socorro, NM Time: 1:30 PM See attached attendance sheet Mr. Larry Voice from FEMA attended meeting via teleconference. 1. Introduction/Sign-in Sheet Mr. Rigel Rucker, the RAMPP Study Manager, began the meeting at 1:30 PM (MT) with a PowerPoint presentation. Introductions of attendees proceeded. All attendees acknowledged that they had signed the sign-in sheet. Mr. Rucker stated that the purpose of this meeting was to provide a project update, present the engineering analyses performed to the communities, and discuss flood protection provided by levees and the mapping of levee protection. Mr. Rucker asked if the communities would forward any Letters of Map Revision (LOMRs) to RAMPP for incorporation in the proposed maps before they go effective. Mr. Rucker asked if the Community Points of Contact list was up-to-date. Ms. Delilah Walsh, the Socorro County Manager, responded that the Chairman for the Socorro County Commission will be changed on January 4, Overview of Flood Study Process Mr. Rucker provided an overview of the study and a complete description of the Flood Mapping Process. Each task was presented in chronological order. Project Scope Mr. Rucker provided an overview of the project scope development and presented a slide showing the countywide proposed panel scheme and studied stream reaches (per study type) to the attendees. The final scope includes: 624 miles of streams studied (mostly Zone A) 18 Digital Flood Insurance Rate Map (DFIRM) panels revised/created Incorporation of all approved LOMRs into the DFIRM panels Base Map Development Mr. Rucker provided an overview of each of the base map layers used for this project. Aerial imagery dated 2009 was acquired from the U.S. Department of Agriculture s (USDA) National Agriculture Imagery Program (NAIP) website. The transportation network was acquired from an E911 database whose gaps were supplemented by the U.S. Census Bureau s Topologically Integrated Geographic Encoding and Referencing (TIGER) road files. TIGER data was also used for the political boundaries. Streamlines were acquired from the USGS National Hydrography Dataset (NHD), and benchmarks came from the National Geodetic Survey (NGS). Finally, Public Land Survey System (PLSS) data was acquired from the U.S. Department of the Interior s (DOI) Bureau of Land Management (BLM) website. RAMPP Project No

2 Topographic Data Development Mr. Rucker provided an overview of the sources for topographic data that were used for this project. Mr. Rucker indicated that the known datasets available countywide were USGS 10-meter Digital Elevation Models (DEMs) and Resource Geographic Information System (RGIS) 10-meter plus DEMs. LiDAR data was acquired within the City of Socorro and supplemented with USGS 10-meter DEMs outside the LiDAR limits. Ortho-converted terrain developed by Bohannan Huston was cleaned of artifacts and used for this analysis as well as best available data. RGIS DEMs were not utilized because they did not meet FEMA Guidelines and Specifications for Flood Hazard Mapping Partners. 3. Flood Study Process Products Mr. Rucker informed the meeting attendees of the preliminary and final products that will be created from this study and made available. These include a Flood Insurance Study Report, a DFIRM Geographic Information System (GIS) Database, and mapping panels in hard copy and digital format (Adobe PDF). Mr. Czosnek asked if the communities would have access to the GIS database. Mr. Rucker replied that a final copy of the digital database with all files used to generate the maps will be provided to all communities when the maps are released preliminary. 4. Letters of Map Change (LOMCs) Mr. Rucker presented a table of LOMCs on a slide to the attendees and stated that all LOMCs will be analyzed in the Summary of Map Actions (SOMA) when the maps are released preliminary. 5. Levees Mr. Rucker stated that levees provide specific levels of protection from flood hazards; however, flood risk still exists behind levees as they can be overtopped in larger flood events or fail if not maintained properly. Mr. Rucker stressed that FEMA does not certify levees; this is the responsibility of the levee owner. Should levee certification be reviewed and approved, FEMA will accredit the levee on a FIRM panel as showing protection. If levee certification is not provided, the area will be mapped with the levee not providing protection. Mr. Rucker further explained that accreditation of levees by FEMA must comply with Code of Federal Regulations (CFR), Title 44, Part 65, Section 10 (44CFR65.10). Procedure Memorandum (PM) 34 requires verification that levee certification requirements continue to be met and PM 43 allows for communities that need more time to comply with certification requirements to sign a Provisionally Accredited Levee (PAL) agreement that will expire in 24 months. Mr. Rucker explained that this topic is especially important to Socorro because there are multiple levees and levee-like structures that protect portions of the community from flooding. These levees include the Matanza Levee south of the City of Socorro, the Socorro Levee west and north of the City of Socorro, and the Rio Grande Levee along the west bank of the Rio Grande. Levee-like structures include Interstate 25 (I-25) and the railroad east of the City of Socorro. Levee Analysis Mr. Rucker explained the types of levee analyses conducted: 1) with levee accreditation, and 2) without levee accreditation. For the latter, only 1 levee is removed at a time. All levee analyses were conducted per FEMA PM 52. Ms. Walsh inquired as to who owns the Socorro levees. Mr. Rucker responded that the City of Socorro owns the Socorro and Matanza levees. Mayor Bhasker verified that the City of Socorro owned the levees and they were only constructed for the 50-year event. Mr. Rucker explained that the Middle Rio Grande Conservancy District owned the Rio Grande levee. Mayor Bhasker indicated that there were plans to reconstruct the Rio Grande Levee in Page 2 of 5

3 Socorro Levee Analysis Mr. Rucker indicated that the Socorro and Matanza Levees were analyzed for this study. This flood control system contains 7.8 miles of total levee length and drains an area of 190 square miles. Engineering analysis consisted of analyzing the floodplain as if each levee did not exist while leaving the others in place. Hydrologic analysis included area reduction factors for determining the flood discharges. An unsteady, two-dimensional model generated by FLO-2D was used for the hydraulic analysis to account for lateral spreading, flood volume and attenuation. Factors not considered in this analysis included: 1) flood storage behind levee and resulting release during a breach, 2) cascading effect of breaches, and 3) breach timing. Levee Discussion Mr. Rucker provided a detailed overview of the levee accreditation process and criteria from the PowerPoint presentation. All effective levees on the FIRMs showing protection on maps must be certified in order to continue being accredited on the new maps. Important points to consider include: The burden to certify the levees is on the levee owner FEMA does not own, maintain or certify levees FEMA s accreditation is NOT a health and safety standard Accreditation is for insurance purposes only Only maps the inundation area of the landward side of levee which would be affected if levee does not provide 1-percent annual chance protection Provisionally Accredited Levee (PAL) may apply if community agrees to certify levee within specified timeframe Ms. Walsh asked if the communities can submit updated certification documents at any time. Mr. Rucker replied that the communities can provide certification packages to FEMA at any time. Ms. Walsh inquired about incorporating new crossings on the FIRM panels. Mr. Rucker stated that the community could incorporate the crossings by submitting LOMRs to FEMA. Mayor Bhasker asked if the Rio Grande levees (when reconstructed) would affect the floodplain mapping. Mr. Rucker indicated that an analysis would need to be conducted to show the effects of internal drainage. He also indicated that a large part of this analysis would need to consider the impact of flooding from the levees to the west. Mr. Czosnek asked if the Rio Grande levees (when reconstructed) would require a flood restudy. Mr. Rucker replied that FEMA does require an internal drainage study as part of the levee certification process and that the levee owner is responsible for submitting this information. Mayor Bhasker asked if the proposed maps would not show flooding in the City if the levees were certified. Mr. Rucker responded that this would have to be determined by the internal drainage analysis. However, some new floodplains were added to the city when RAMPP analyzed flooding with the levees in place. Mayor Bhasker inquired if the previous (effective) study accounted for sheet flow from the mountains. Mr. Rucker indicated that flow from the mountains was shown on the effective panels. However, effective panels show the levees as being accredited, so the flow did not enter the City of Socorro even though there is no evidence of certification. Mayor Bhasker asked if any economic impact analyses had been conducted for the City of Socorro as a result of the floodplain analysis. Mr. Rucker indicated that a change map showing the difference in floodplain extents Page 3 of 5

4 Page 4 of 5 Meeting Minutes between effective and preliminary will be produced on RAMPP s website, and this could aid in an economic analysis. However, RAMPP was not tasked with conducting this analysis. Mayor Bhasker asked if existing mortgage terms could be affected by remapping. Ms. Walsh responded that the lender may reserve the right to change the terms should a change in the flood insurance risk zone occur. Mr. Rucker mentioned that the zone could be grandfathered ; however, rates could change. Special rules apply for pre-firm structures. Mr. Rucker mentioned that handouts had been provided documenting grandfathering and other insurance related topics. Mr. Czosnek asked if he should notify the constituents prior to the preliminary maps going effective. Mr. Rucker indicated that all communities should begin outreach with the public and local officials immediately to let them know about the study. Mr. Rucker also noted that constituents will have to the right to view the maps and file appeals during the upcoming 90-day appeal period. Mayor Bhasker commented that he would like to know the economic repercussion of mapping the City in the 1- percent annual chance floodplain. He explained that it may be in the City s best interest to pay for the reconstruction and certification of the City-owned levees through a funding mechanism (i.e. bond) that would be offset by reduced flood insurance rates. Mr. Rucker provided paper copies and an overhead display of the existing floodplains, floodplains with the levees de-accredited, and floodplains with accreditation. Mr. Rucker noted that the preliminary DFIRMs would show floodplains without levee accreditation. 6. Schedule Mr. Rucker explained the schedule for the remainder of the project. He noted the Preliminary products will be issued to the communities on March 14, After this date, the project moves into the post-preliminary phase. 7. Post Preliminary Process and Map Adoption Mr. Rucker discussed the post preliminary process and emphasized the three stages: Consultation Coordination Officer (CCO) Meeting: days after Preliminary Appeal Period and Resolution: ends 3 months after the CCO Meeting Map Adoption: ends 6 months after the Letter of Final Determination He referred meeting attendees to FEMA Publication 495 Adoption of Flood Insurance Rate Maps by Participating Communities for more information. 8. Information Resources Mr. Rucker indicated that one of the goals of FEMA and RAMPP was to maintain constant communication and outreach to community officials. He indicated that there are outreach tools from FEMA to assist in keeping the community informed about the process. These tools are made available on the RAMPP website, which is located at Mr. Rucker also indicated where the monthly project progress report and fact sheets are located in the Public section on this website. He recommended that each person at the meeting use the documentation on this website heavily, and to begin outreach to the community immediately. Please refer to the for more updates on the project. 9. Community Questions and Comments No specific concerns on the floodplain delineations were raised by the Communities at the meeting. Mr. Rucker stated that RAMPP will conduct a separate Over-The-Shoulder review meeting with Socorro County and other communities within the next month.

5 Mr. Mike Czosnek asked if he could keep the hardcopy exhibits provided by RAMPP. Mr. Rucker responded by asking FEMA representative, Mr. Larry Voice, on the phone if this was permissible. Mr. Voice stated it was okay. Mr. Bear Albrecht asked if he could have electronic copies of the exhibits. Mr. Rucker provided.pdfs to Mr. Albrecht. 10. Meeting Adjourned at 2:45 PM (MST) These notes are an interpretation of discussions held. Please provide any additions or corrections to the originator within 5 days of the date signed; otherwise they will be assumed correct as written. Prepared by: Rigel L. Rucker Date: _12/16/10 Page 5 of 5