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HomeMy WebLinkAbout2002-03-18 City Council (3)City of Palo Alto City Manager’s Report TO:HONORABLE CITY COUNCIL FROM:CITY MANAGER DEPARTMENT: PUBLIC WORKS DATE:MARCH 18, 2002 CMR:184:02 SUBJECT:STATUS REPORT ON PROPOSED CHANGES TO TIDAL FLOODPLAIN BOUNDARY This is an information report and no Council action is required. BACKGROUND Congress established the National Flood Insurance Program (NFIP) in 1968 to provide flood insurance to residents and businesses in flood-prone communities that elect to participate in the program. In return, the Federal Emergency Management Agency (FEMA) imposes requirements on the participating community, including the codification of federal floodplain management regulations into local ordinances. Palo Alto initially elected to take part in the NFIP in 1979. FEMA has delineated Palo Alto’s Special Flood Hazard Areas (SFHA) on its. Flood Insurance Rate Maps (FIRM) for those areas subject to flooding in the one percent flood. The one percent flood has a one percent chance of occurring in any given year. It is sometimes referred to as the 100-year flood, because it is the flood that would be equaled or exceeded on an average of once every hundred years, measured over a long time periodl There are two basic requirements applicable to properties in a FEMA-designated SFHA: flood insurance and special building requirements. The flood insurance requirement is not administered by the City. Federally-backed lending institutions are mandated by law to require borrowers to obtain flood insurance for all loans issued for structures within an SFHA. City staff is responsible for enforcing the special building requirements, which have been incorporated into Chapter 16.52 (Flood Hazard Regulations) of the Palo Alto Municipal Code.. These requirements apply to new construction ahd ."substantial improvement" of existing structures within an SFHA. The primary special building requirements involve constructing the lowest floor of a structure at or above the expected flood level, installing adequate vents in foundation walls, placing building utilities above the flood level, and use of water-resistant building materials. FEMA has identified two distinct flood hazards in Palo Alto: creek flooding and tidal flooding. Several areas of the City are subject to flooding caused by the overtopping of CMR:184:02 Page 1 of 3 local creeks in the event of a one percent flood. In addition, a large area on the eastern side of the city is subject to tidal flooding in the event of failure or overtopping of the Bayfront levees during a one percent tide on San Francisco Bay. Approximately 2,400 Palo Alto properties are located within the tidal floodplain designated on the FEMA Flood Insurance Rate Maps (see Attachment A). DISCUSSION The tidal floodplain was mapped by a FEMA consultant in 1980. Since the one percent tide level is expected to reach an elevation of eight feet above sea level, the boundary of the tidal floodplain should be the eight-foot ground contour. This is where the edge of the ponded floodwaters would meet the ground (i.e. similar to a bathtub ring). After receiving several inquiries from the public about the accuracy of the FIRM, staff used topographic information collected for the City’s Geographic Information System (GIS) to map the eight-foot ground contour (see Attachment A). The accuracy of the GIS mapping was verified through a spot check of elevations in the field. Upon comparing the GIS data with the FIRM, staff has concluded that the floodplain boundary has been drawn incorrectly on the FIRM. Using staff’s modified floodplain boundary, 290 properties currently within the floodplain would be excluded and 170 properties outside the current floodplain would be added. FEMA has a standard procedure, the Letter of Map Revision (LOMR) process, for requesting changes to the FIRM. Staff intends to submit a LOMR application to FEMA, requesting that it change the tidal floodplain boundary to reflect the City’s mapping data. The proposed map change would result in a net reduction of 120 in the number of properties located within the floodplain. Prior to sending the LOMR application, however, staff will conduct outreach to the affected property owners. First, staff will send a letter to all the property owners informing them of the proposed mapping change and inviting them to a public meeting to learn more about the issue (see Attachment B). At the public meeting, the floodplain maps will be displayed and explained, and staff will answer questions about the proposed mapping changes and the implications of having a property within a designated floodplain. Following the meeting, there will be a 30-day appeal period, during which time property owners will have the opportunity to challenge the City’s data using site-specific elevation data provided by a licensed surveyor. Following the appeal period and the resolution of any appeals, staff will submit the LOMR application to FEMA. It is expected that FEMA will respond to the City’s application within approximately 60 days. Once the City receives the approved LOMR from FEMA, staff will notify the affected property owners through individual letters. In addition, the map changes will be publicized through news releases, an item in the City Manager’s Weekly Memo, and an informational report to Council. TIMELINE The process to change the tidal floodplain boundary on the FIRM is expected to follow the following timeline: CMR:184:02 Page 2 of 3 March 18, 2002 March 20, 2002 April 2002 May 2002 July 2002 August 2002 ATTACHMENTS Attachment A: Attachment B: PREPARED BY: DEPARTMENT HEAD: Informational report to City Council Letters mailed to affected property owners Public meeting on proposed mapping changes Start of 30-day appeal period End of appeal period Submittal of LOMR application to FEMA Expected receipt of approved LOMR from FEMA Public outreach on mapping changes Map of existing and proposed tidal floodplain boundary Sample letters to property owners affected by proposed changes JOE TERESI ,~ Senior~ GLENN S. ROBERTS Director of Public Works CITY MANAGER APPROVAL: cc: t~ ~II~Y HARRISON Assistant City Manager Jennie Micko, Santa Clara Valley Water District Bonnie Packer, Palo Verde Neighborhood Association Annette Ashton, Midtown Residents Association Michael Gagliasso, Middlefield Road Residents Assn. Jean Wilcox, Charleston Gardens Association Larry Mitchell, Meadow Park Homeowners Assn. Charlotte Cagan, Palo Alto Chamber of Commerce Peninsula-West Valley Realtors Association mapping CMR: 184:02 Page 3 of 3 ATTACHMENT A i! i~ LEGEND Existing SFHA Zone AH Zone AE Zone AO Added to SFHA Removed from SFH/~ Areas Affected by Proposed Change to Tidal Floodplain Boundary March 2002 This map is a product of the City of Palo Alto GIS 0’1500’ March 11, 2002 ATTACHMENT B PROPERTIES ADDED TO FLOODPLAIN ¯ <<Assessee>> <<In Care of Name>> <<Mailing_Address~} <<Mailing_City_and_State}> <<Mailing_Zip_Code>} Subject:Revision to Tidal Floodplain Boundary Dear Property Owner: You are invited to attend an informational public meeting on April 2, 2002 regarding proposed changes to the Federal Emergency. Management Agency’s (FEMA) Flood Insurance Rate Map (FIRM) that will affect your property at ~Situs Street Address~>. The meeting will be held at the Cubbedey Theater, 4000 Middlefield Road. A summary of the proposed map changes is provided below. As you are probably already aware, your property is currently near a Special Flood Hazard Area (SFHA) as delineated by FEMA. The nature of this flood hazard is the 100- year high-tide level that could reach an elevation of eight feet above mean sea level. This high-tide level could affect a large portion of Pal0 Alto if the levee system around the Baylands were to fail or overtop. The tidal floodplain boundary shown on FIRM Panel Number 060348-003E is meant to correspond to the 8-foot elevation contour of the land. Review by City staffhas revealed that the surface elevation data used by FEMA to prepare the map had some inaccuracies. As a result, the tidal flood boundary shown on the FIRM does not accurately represent the extent of flooding expected to occur in the event of an 8-foot high tide. The City of Palo Alto has more accurate surface elevation data. The City is.planning to submit this data to FEMA along with an application for a Letter of Map Revision (LOMR) to change the boundary of the tidal flood zone on the FIRM. This proposed map revision will result in the addition, of your property and others to the Special Flood Hazard Area (see attached map). In addition, some properties that are currently shown to be within the designated floodplain will be removed from the Special Flood Hazard Area. We are sending notices to all affected properties. The revised maps and relevant associated information will be presented at the public meeting and are available for inspection in the Public Works Engineering office on the 6th. floor of City Hall, 250 Hamilton Avenue. We anticipate that the LOMR application will be submitted to FEMA in early May 2002. Prior to that date, there will be an appeal period during which property owners who believe that the City’s proposed map revisions are incorrect may submit a protest letter with supporting land surface elevation data documenting the alleged error. Any elevation data submitted to the City must be measured and documented by a licensed engineer or land surveyor. The LOMR application will be adjusted accordingly prior to submittal to FEMA if errors or omissions are identified. Once the application is submitted, it is expected that FEMA will take approximately three months to process the application and issue a Letter of Map Revision. The City will issue a follow-up letter to all affected property owners to notify them of the effective date of the map change. Once a property is added to the SFHA, the mortgage lender for the home on that property must require the borrower to purchase flood. insurance, and any future construction on the property is subject to special building requirements enforced by the City. A summary of the requirements applicable to properties in the SFHA is attached for your information. Further information will be presented at the community meeting on April 2. If you have any questions or need further information, please contact me at 329-2469 or Joe Teresi at 329-2129. Sincerely, Matt Raschke Engineer Engineering Division Attachments March 11, 2002 ATTACHMENT B PROPERTIES REMOVED FROM FLOODPLAIN ~Assessee~ ~dn Care of Name~ ~dvl~iling_Address~ ~Mailing_City_and_State~ ~Mailing_Zip_Code~ Subject:Revisionto Tidal Floodplain Boundary Dear Property Owner: You are invited to attend an informational public meeting on April 2, 2002 regarding proposed changes to the Federal Emergency Management Agency’s (FEMA) Flood Insurance Rate Map (FIRM) that will affect your property at ~Situs Street Address~. The meeting will be held at the Cubbedey Theater, 4000 Middlefield Road. A summary of the proposed map changes is provided below. As you are probably already aware, your property is in or partially in a Special Flood Hazard Area (SFHA) as delineated by FEMA. The. nature of this flood hazard is the 100- year high-tide level that could reach an elevation of eight feet above mean sea level. This high-tide level could affect a large portion of Palo Alto if the levee system around the Baylands were to fail or overtop. The tidal floodplain boundary shown on FIRM Panel Number 060348-003E is meant to correspond to the 8-foot elevation contour of the land. Review by City staff has revealed that the surface elevation data used by FEMA to prepare the map had some inaccuracies. As a result, the tidal flood boundary shown on the FIRM does not accurately represent the extent of flooding expected to occur in the event of an 8-foot high tide. The City of Palo Alto has more accurate surface elevation data. The City is planning to submit this data to FEMA along with an application for a Letter of Map Revision (LOMR) to change the boundary of the tidal flood zone on the FIRM. This proposed map revision should result in the removal of your property and others from the Special Flood Hazard Area (see attached map). In addition, some properties that are currently shown to be outside the designated floodplain will be added to the Special Flood Hazard Area. We are sending notices to all affected properties. The revised maps and relevant associated information will be presented at the public meeting and are available for inspection in the Public Works Engineering office on the 6th floor of City Hall, 250 Hamilton Avenue. We anticipate that the LOMR application will be submitted to FEMA in early May 2002. Prior to that date, there will be an appeal period during which property owners who believe that the City’s proposed map revisions are incorrect may submit a protest letter with supporting land surface elevation data documenting the alleged error. Any elevation data submitted to the City must be measured and documented by a licensed engineer or land surveyor. The LOMR application will be adjusted accordingly prior to submittal to FEMA if errors or omissions are identified. Once the application is submitted, it is expected that FEMA will take approximately three months to process the application and issue a Letter of Map Revision. The City will issue a follow-up letter to all affected property owners to notify them of the effective date of the map change. Once a property is removed from the SFHA, the mandatory flood insurance purchase requirement and the special building requirements are eliminated. If you have any questions or need further information, please contact me at 329-2469 or Joe Teresi at 329-2129. Sincerely, Matt Raschke Engineer Engineering Division Attachment