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Digital Flood Insurance Rate Map DFIRMTO: The Honorable Mayor and City Council Members FROM: Michael C. Van Milligen, City Manager SUBJECT: Correspondence with FEMA regarding Digital Flood Insurance Rate Map (DFIRM) DATE: November 12, 2009 Planning Services Manager Laura Carstens is recommending approval of a letter to the Federal Emergency Management Agency requesting changes to the Digital Flood Insurance Rate Map (DFIRM) and stating that the City of Dubuque will not provide additional GIS data requested by FEMA for the North End. I concur with the recommendation and respectfully request Mayor and City Council approval. Michael C. Van Milligen MCVM:jh Attachment cc: Barry Lindahl, City Attorney Cindy Steinhauser, Assistant City Manager Laura Carstens, Planning Services Manager THE CITY OF Dubuque I~~LTB E i ~~ Masterpiece on the Mississippi ° 200 TO: Michael Van Milligen, City Manager ~~~ FROM: Laura Carstens, Planning Services Manager ~`~5'~,- SUBJECT: Correspondence with FEMA regarding DFIRM DATE: November 12, 2009 INTRODUCTION This memorandum transmits a draft letter from Mayor Buol to FEMA (Federal Emergency Management Agency) requesting changes to the preliminary DFIRM (Digital Flood Insurance Rate Map), and stating that the City of Dubuque will not provide additional GIS data requested by FEMA for the North End. A set of talking points for our federal and state legislators is enclosed. A map depicting the changes from the current to the new flood maps is enclosed also. DISCUSSION Previously, the City transmitted a GIS shape file prepared by engineering consultant HDR, who worked with the City on the Drainage Basin Master Plan. The shape file reflected the area of the North End within the new Zone A proposed by FEMA. The GIS shape file also reflected the existence of the Carter Road detention basin completed in 2004 and the West 32"d Street detention basin completed this spring. The accompanying project summary outlined the engineering models and techniques used to establish the predicted storm water flooding limits. City Engineering and Planning Services staff discussed this information with FEMA representatives and their engineering consultants during a conference call on October 22, 2009. We had anticipated that the provision of this information would help in the removal of some of the properties from the regulated flood plain proposed for the North End. Unfortunately, this does not appear to be the case. FEMA has requested that the City provide additional GIS data from the Drainage Basin Master Plan to establish a Zone A boundary. The City's Drainage Basin Master Plan was intended to address long standing issues with urban storm sewer conveyance problems in this area of the community -not flooding associated with a creek or river. These types of urban storm water problems are common throughout the U.S. The history of localized street flooding and basement flooding experienced in the North End does not rise to the level of being designated as a regulatory flood plain. This data request from FEMA has been discussed by staff in the Engineering, Planning Services, Legal and City Manager's Offices. City staff recommends that the City not provide any further data to FEMA. We feel that we will have to appeal the DFIRM, and we do not want to be in the unenviable position of appealing our own data. Correspondence with FEMA regarding DFIRM Page 2 FEMA has indicated that if the City does not provide the data, then FEMA will use the best available data to determine a flood hazard area and it may be larger than our GIS shape file may indicate. Our concern, however, is that any flood hazard area shown in the North End is a mistake and recommend the City continue to ask FEMA to remove this area from the DFIRM. The enclosed letter to FEMA states that the City is unable to supply any relevant data for the DFIRM. The data we have supplied to date relates to our planning studies of the risk of flooding due to capacity issues for the storm water management system in the North End. This data does not constitute an engineering study to determine a regulatory flood plain, and we oppose FEMA's use of this data to establish a Zone A in the North End. The letter goes on to state that the City believes that the new Zone A shown on the preliminary DFIRM is an error, is not supported by FEMA's Flood Insurance Study (FIS) Report for Dubuque County, and was established using rudimentary, regression analysis which is inappropriate for designating a flood hazard area. The letter contains additional remarks about the history of and impacts to the North End, the City's participation in the National Flood Insurance Program, the findings in previous and current FIS Reports for Dubuque, and the lack of standard engineering analysis for determining the new Zone A areas. The letter requests the removal of the new Zone A areas for these reasons. City staff has discussed alerting our federal and state legislators to the situation we face. In contacting other cities in Iowa, we have learned that Dubuque appears to be the only city facing a significant increase of structures in the flood plain, from 70 to over 1,700. A series of talking points to be shared with our federal and state legislators and their staff is enclosed. The Iowa Department of Natural Resources (IDNR) is the state agency that has oversight for flood plain management. The IDNR must review and approve all FIS Reports and flood studies that will be used for regulating flood plain development. This review is to ensure that: an adequate study was performed, IDNR's study standards are followed, different studies on the same stream are consistent, and all map revisions to reflect stream modifications and flood control structures are based on projects that have been approved by IDNR. IDNR potentially could be enlisted to support our position if they agree with the City of Dubuque. RECOMMENDATION City staff recommends transmittal of the enclosed letter from Mayor Buol to FEMA requesting removal of the proposed Zone A flood plain boundary delineations on the preliminary DFIRM, and approval to share the enclosed talking points and map with our federal and state legislators. Enclosures cc: Gus Psihoyos, City Engineer Deron Muehring, Civil Engineer II Kyle L. Kritz, Associate Planner Tim O'Brien, Assistant City Attorney Teri Goodmann, Assistant City Manager Office of the Mayor & City Council THE CITY OF Dubuque City Hall m 50 West 13 Street D V L E Dubuque,lA 52001-4864 ,AFA~Ia i www.cityofdubuque.org I I. Mcisterpiece on the Mississippi Zoos November 12, 2009 Rick Nusz Hydraulic Engineer FEMA Region VII 9221 Ward Parkway Ste 300 Kansas City MO 64114 Dear Mr. Nusz: This letter is in response to your request for the City of Dubuque to provide data for the Zone A covering a large portion of the North End of Dubuque on FEMA's preliminary DFIRM (Digital Flood Insurance Rate Map). The City of Dubuque is not comfortable supplying any additional data related to the area currently designated as a Zone X that might be used to increase the size of the proposed new Zone A shown in the City's North End. As indicated in previous correspondence, the City believes that the new Zone A shown on the preliminary DFIRM is unfounded as the storm water drainage issues are related to basement flooding due to storm sewer and street storm water conveyance capacity limitations. North End History and Impacts The North End is laid out in a traditional grid street system and has been fully developed for approximately 100 years. With the construction of the original Bee Branch storm sewer system, many of the problems associated with storm water were resolved; otherwise, the area would not have fully developed in its present configuration. The historical records since the construction of the Bee Branch Storm sewer system would suggest the only problems have been associated with storm water creating relatively minor street flooding and water in basements. The City's latest project to rebuild the Bee Branch storm sewer system addresses problems associated with the age of the system and additional storm water created by development in upland areas since the original Bee Branch storm sewer was constructed. It is very typical for cities to design their storm sewer systems to handle the 10-year storm. Obviously, this can be exceeded from time to time in any given year; in those instances streets are asked to carry this additional flow. The fact that cities' storm sewer systems can be overwhelmed by particular storm events and there is street flooding does not render all those areas throughout the United States as being in a regulated flood plain. Many streets in Dubuque actually have curbs that are nearly two feet in height to allow the street to carry more storm water. Letter to Rick Nusz, FEMA November 17, 2009 Page 2 From the time that the City's Drainage Basin Master Plan (DBMP) was completed in 2001, the City has never indicated that there are 1,150 properties in the 100-year flood plain. The City has simply indicated that there are 1,150 properties at risk of flood damage during heavy rains. While the DBMP findings were based on sophisticated models (the US Army Corps of Engineers' HEC-HMS and the US EPA's SWMM models), it was not the intent to identify a flood plain -only quantify/qualify a drainage issue and present potential solutions. The City has already started implementing the solutions with the last to be completed in 2013. The proposed designation of the North End of Dubuque as a Zone A would increase the number of structures over 500 square feet located in special flood hazard areas from approximately 70 to approximately 1,741. The most significant impact of having a property in a flood plain is that new construction, new additions, and even existing structures, which may be undergoing rehabilitation, may have to be elevated or flood proofed as part of any substantial improvement to a property. In Zone A, where there are no base flood elevations, an engineer must be hired to determine the base flood elevation, in order to determine how high an addition or new structure must be elevated. The area proposed for inclusion in the new Zone A on the North End of Dubuque includes some of the City's oldest housing stock (dating from the late 1800s) and long- standing businesses and industries. These neighborhoods have a higher percentage of low to moderate income households and racial and ethnic minorities than the City as a whole. The City of Dubuque has focused reinvestment efforts in these neighborhoods for many years and has installed upstream storm water management facilities to alleviate problems with the storm water system. The delineation of these neighborhoods as a Zone A flood hazard area will reverse the progress the City has made. The Zone A designation will result in neighborhood disinvestment and blighting conditions. Placing this burden on approximately 1,400 low to moderate income households in the new Zone A is unacceptable. The burden to determine base flood elevations (BFEs) must rest with FEMA and not the citizens of Dubuque if FEMA is determined to designate this area as a special flood hazard area because of storm water issues. National Flood Insurance Program in Dubuaue The City of Dubuque was the first community in Iowa to join the National Flood Insurance Program (NFIP) on April 2, 1971. The City's current flood maps were revised in September 1989. These maps updated a previous set from the 1970s. The North End of Dubuque was not shown as a special flood hazard area in either of the two previous FIRM maps. The City of Dubuque has been very conscientious in its application of the NFIP requirements. The City has never approved a variance from the NFIP requirements. The City has not allowed a single new residential structure to be built in any Special Letter to Rick Nusz, FEMA November 17, 2009 Page 3 Flood Hazard Area (SFHA). The only new structures built in SFHAs have been commercial structures that have been elevated and/or flood proofed in compliance with NFIP requirements. Inaccuracies of Preliminary DFIRM The inaccuracies that City staff found in the preliminary DFIRM maps will make it difficult to enforce NFIP requirements in areas newly designated as a SFHA. The preliminary DFIRM shows flooding heights on Kaufmann Avenue such that vehicles would be submerged, when the 100+ year history that shows no such flooding having ever occurred. This error will make citizens question the validity of the new maps, and rightly so. The City of Dubuque cannot stress enough the far reaching negative impacts to the North End that designation as a Zone A will have. If this area had a history of flood damage, the City would not question its designation as a special flood hazard area; however, the written record of over 100 years does not support such a designation. Flood Boundary Methodology The accuracy of the preliminary DFIRM also calls into question the methodology used to establish the flood boundaries initially. In the conference call of October 22, 2009 with FEMA, City staff and AECOM /Watershed Concepts staff, it was stated that FEMA did not use a standard model for the new Zone A areas. The Nebraska model, INSECT, was used. This model depicts normal depth at cross sections. You confirmed that FEMA was using Iowa regression analysis. It was further discussed at the conference call that FEMA was using new modeling, and it was not done to an engineering standard that would enable elevations to be published. You stated that FEMA has limited funding to do an engineering study that would determine BFEs. Therefore, this burden will be placed on citizens in the City of Dubuque who have the least means; the City finds this unacceptable. If FEMA does not have the funding to do an engineering study, using sufficiently sophisticated models to produce BFEs, then no new Zone A areas should be mapped. By failing to do more than a rudimentary planning study, FEMA fails to provide the BFEs needed for the City to regulate development in the North End. The Zone A in the North End, in particular, will create neighborhood disinvestment. It also will subject low and moderate income households to costly flood insurance that they cannot afford, further acerbating disinvestment in this historic neighborhood. The shallow flooding experienced in the new Zone A areas on the preliminary DFIRM is due to local drainage problems with the capacity of the City's storm sewer system. These areas do not rise to the level of a regulatory flood plain, and should not be mapped as A Zones by FEMA. Increasing our inventory of structures in the flood plain from 70 to over 1,700 through non-standard mapping would be a mistake. Letter to Rick Nusz, FEMA November 17, 2009 Page 4 Flood Insurance Studv By definition, a Flood Insurance Study (FIS) Report is an appraisal of a community's flood problems, including historic floods. The City of Dubuque's FIS Report from FEMA, revised on September 6, 1989, does not mention any flooding hazards in the North End. The July 2009 FIS Report for Dubuque County and incorporated areas provided by FEMA to the City of Dubuque earlier this year does not mention any flooding hazards in the North End. On page 4, the 2009 FIS Report indicates the 1989 FIS Report for the City of Dubuque is a reference document. On Page 5, the 2009 FIS Report described the Scope of Study for the area studied. The report states, "the areas studied were selected with priority given to all known flood hazard areas and areas of projected development or proposed construction." The City of Dubuque is not included in the following section entitled Community Description on pages 6-9. The City of Dubuque is not listed in the next section, Principal Flood Problems, on pages 9-11. On page 12, the City of Dubuque is identified as having no flood protection measures in existence or proposed. The City has a floodwall and levee system along its Mississippi Riverfront that provides protection from the 100-year and 500-year flood events. Shouldn't this levee system be acknowledged in the 2009 FIS Report? The 2009 FIS Report lists Engineering Methods for hydrologic analyses (pages 13-17) and hydraulic analyses (pages 18-23). The North End is not mentioned in either of these analytical descriptions with respect to flooding. The 2009 FIS Report describes flood plain management applications on pages 23-25. This section speaks to streams with respect to regulated flood plains, floodways, and floodway fringes. Urban storm water in the North End of Dubuque is never mentioned in this context. Conclusion , The point of the NFIP is for communities to regulate floodplain development. In Dubuque, we have an excellent record of flood plain management. The Zone A areas shown on the preliminary DFIRM are not supported by the FIS Reports, and therefore including them in the DFIRM would be a mistake that would burden low and moderate income households with costly flood insurance that they cannot afford, further acerbating disinvestment in their historic neighborhoods. The new Zone A areas should be removed entirely from the City of Dubuque's DFIRM before the FEMA public meeting, for the benefit of everyone. Sincerely, Roy D. Buol Mayor Request to FEMA to change the City of Dubuque's preliminary DFIRM (Digital Flood Insurance Rate Map) Introduction The City of Dubuque is requesting that the Federal Emergency Management Agency (FEMA) remove new flood areas from the preliminary DFIRM (Digital Flood Insurance Rate Map). Without the use of standard engineering computer models, FEMA has proposed a DFIRM that would significantly expand the number of properties in the city designated as being in a regulated flood plain from 70 structures to over 1,700 structures! Adoption of the proposed DFIRM would place a heavy financial burden on approximately 1,400 low to moderate income households resulting in neighborhood disinvestment and decline. Background On July 15, 2009, the City of Dubuque received the preliminary DFIRM and the FIS (Flood Insurance Study) Report as part of FEMA's Flood Map Modernization Program. The program is designed to update on a nationwide basis the flood insurance rate maps of member communities and counties in the National Flood Insurance Program (NFIP). The City of Dubuque was the first community in Iowa to join the NFIP on April 2, 1971. The City's current flood insurance rate map is from 1989. The City has regulated floodplain development since 1990. The City of Dubuque has been very conscientious in its application of the NFIP requirements. The City has never approved a variance from the NFIP requirements. The City has not allowed a single new residential structure to be built in any flood hazard area. The only new structures built in flood hazard areas have been commercial structures elevated and/or flood proofed in compliance with the NFIP requirements. Discussion Enclosed is a map that indicates new flood zones for Zone A (no base flood elevations determined) and Zone AE (base flood elevations determined) proposed by FEMA. These zones mark the 100-year flood plain. In addition, this map shows the 500-year flood plain and Zone X. Zone X is areas outside the 500-year flood plain and areas protected by the City's floodwall. General Impact on Properties The most significant impact of having a property in a flood plain is that new construction, new additions and even the existing structures may have to be elevated or flood proofed as part of any substantial improvement to a property. In Zone A, base flood elevations (BFEs) haven't been determined, so the property owner first must hire an engineer to determine the BFEs in order to determine how high an addition or a new structure must be elevated. Flood insurance will be required by a commercial lender if the property owner refinances an existing structure or buys a structure in a flood plain. Flood insurance for properties in a flood plain is higher than flood insurance for properties outside a flood plain. For example, flood insurance for a single family home with a value of $75,000 and contents valued at $30,000 would cost about $260 annually outside a flood area. This insurance rises to about $844 annually for the same home in a designated flood area -and this assumes a $2,000 deductible for both home and contents! Concerns with New North End Flood Zones We are concerned with all of the new Zone A areas on the DFIRM. We are particularly concerned about the new Zone A in the North End. The North End includes some of the city's oldest housing (dating from the late 1800's) and long-standing businesses and industries. These neighborhoods have a higher percentage of low to moderate households and racial and ethnic minorities than the city as a whole. Request to FEMA to change the City of Dubuque's preliminary DFIRM (Digital Flood Insurance Rate Map) The City has focused reinvestment efforts in these neighborhoods, and installed upstream storm water management facilities to alleviate problems with the storm water system. Delineation of these neighborhoods as a Zone A flood hazard area will reverse the progress we've made. The Zone A designation will result in neighborhood disinvestment and blighting conditions. Placing this burden on 1,400 property owners in the new Zone A areas is unacceptable. Inadeauate Studv The large Zone A for the North End reflects the City's Drainage Basin Master Plan findings on flooding related to the Bee Branch storm sewer. The City's Drainage Basin Master Plan was intended to address storm sewer conveyance problems -not flooding associated with a creek or river. These types of urban storm water problems are common throughout the U.S. The history of localized street flooding and basement flooding experienced in the North End does not rise to the level of being designated as a regulatory flood plain. The City's Drainage Basin Master Plan is a planning study; it did not detail precisely which structures would be impacted. It identifies a generalized area that appears to be at risk from storm sewer backups or overflows. We believe that FEMA is identifying a storm sewer problem rather than a flooding issue connected with a flood plain along a stream or river. City staff provided FEMA with data and information on planned drainage basin improvements like the Bee Branch Creek Restoration Project as well as storm water improvements such as the Carter Road dam and 32"d Street detention areas that address existing storm water issues. City staff held a conference call with FEMA staff and their engineering consultants on October 22, 2009. FEMA staff acknowledged they did not use a standard model for the new Zone A areas. They discussed that FEMA was using new modeling, and it was not done to an engineering standard that would enable BFEs to be published. FEMA has limited funding to do an engineering study that would determine BFEs. We hoped this information would help remove properties from the flood plain proposed for the North End. Unfortunately, it appears that FEMA will map the North End without adequate study. If FEMA does not have the funding to do an engineering study correctly, using sufficiently sophisticated models to produce BFEs, then no new flood areas should be mapped. The burden of determining the base flood elevations (BFEs) must rest with FEMA, not the citizens of Dubuque. The City of Dubuque requests that FEMA show all new Zone A areas with BFEs determined, so that they are converted to Zone AE areas on the DFIRM - if in fact these even are special flood hazard areas. The shallow flooding experienced in the new Zone A areas on the preliminary DFIRM is due to local drainage problems with the capacity of the City's storm sewer system. These areas do not rise to the level of a regulatory flood plain, and should not be mapped as Zone A by FEMA. Increasing Dubuque's inventory of structures in the flood plain from 70 to over 1,700 through non-standard mapping would be a mistake as it would place a heavy financial burden on approximately 1,400 low to moderate income households resulting in neighborhood disinvestment and decline. If you have questions or need additional information, please contact Laura Carstens, Community Flood Plain Administrator at 563.589.4210 or IcarstenCa~cityofdubugue.org. 2 Legend ~ _~. "~ ~ ~~~ `~ -, * ~ 3. i ~ ~ i ulA ".:. 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