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HomeMy WebLinkAboutA002 - Staff Report dated November 14, 2012 ITEM #: 5 CITY OF AMES DATE: 11/14/12 DEPARTMENT OF PLANNING AND HOUSING REPORT TO THE ZONING BOARD OF ADJUSTMENT DATE PREPARED: November 9, 2012 MEETING DATE: November 14, 2012 REQUEST FOR A CONDITIONAL USE PERMIT TO ALLOW AN ALTERNATIVE METHOD OF ELEVATION IN THE FLOODWAY FRINGE: To allow the reconstruction of a multi-family apartment at 301 S. 5th Street. PROPERTY OWNER: South Meadows Housing Cooperative APPLICANT: Chuck Winkleblack LOCATION: 301 S. 5th Street ZONING: High Density Residential PROJECT DESCRIPTION: The multi-family structure at 301 S. 5th Street was heavily damaged by fire in July, 2012. The damage exceeded 50 percent of the value of the structure, thus requiring that any repair or reconstruction be done to meet the current flood plain regulations. The Ames Municipal Code requires that residential structures be elevated to three feet above the base flood elevation (the water surface level of a flood having a 1 percent annual chance of occurrence, otherwise known as the 100-year flood). The flood plain regulations also require that the elevation extend 18 feet beyond the perimeter of the structure. The owner proposes to reconstruct the apartment (see the accompanying staff report regarding the Special Use Permit) and to reuse the existing foundation and ground level parking structure. Since the ground level parking is within the walls of the structure, it is not possible to place fill 18 feet around the perimeter of the building to meet the requirements without impacting the existing parking arrangement. APPLICABLE LAW: A The laws applicable to this case are as follows: Chapter 9, Section 9.1(2) of the Ames Municipal Code states: It is the purpose of this ordinance to promote the public health, safety, and general welfare by minimizing those flood losses described in Section 9.1(2) with provisions designed to: (a) Reserve sufficient floodplain area for the conveyance of flood flows so that flood heights and velocities will not be increased by greater than one (1) foot. (b) Restrict or prohibit uses which are dangerous to health, safety, or property in times of flood or which cause excessive increases in flood heights or velocities. (c) Require that uses vulnerable to floods, including public utilities, which serve such uses, be protected against flood damage at the time of initial construction or substantial improvement. (d) Protect individuals from buying lands, which are unsuited for intended purposes because of flood hazard. (e) Assure that eligibility is maintained for property owners in the community to purchase flood insurance through the National Flood Insurance Program. Chapter 9, Section 9.5 of the Ames Municipal Code states: Section 9.5 Floodway Fringe Overlay District (2) Performance Standards. All uses must be consistent with the need to minimize flood damage and shall meet the following applicable performance standards. (a) All structures shall (i) be adequately anchored to prevent flotation, collapse or lateral movement of the structure, (ii) be constructed with materials and utility equipment resistant to flood damage, and (iii) be constructed by methods and practices that minimize flood damage. (b) Residential buildings. All new or substantially improved residential structures shall have the lowest floor, including basements, elevated a minimum of three (3) feet above the base flood elevation level. Construction shall be upon compacted fill which shall, at all points, be no lower than three (3) feet above the base flood elevation level and extend at such elevation at least 18 feet beyond the limits of any structure erected thereon. Alternate methods of elevating (such as piers) may be allowed, subject to favorable consideration by the Zoning Board of Adjustment and issuance of a Conditional Use Permit, where existing topography, street grades, or other factors preclude elevating by fill. In such cases, the methods used must be adequate to support the structure as well as withstand the various forces and hazards associated with flooding. All new residential buildings shall be provided with a means of access which will be passable by wheeled vehicles during the base flood elevation. 2 and Section 9.5 (2)(k)(ii): New and substantially improved structures must be designed (or modified) and adequately anchored to prevent flotation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy. Chapter 9, Section 9.7 of the Ames Municipal Code states: a. Factors upon which the decision of the Board shall be based. In passing upon requests for Conditional Uses or Variances, the Zoning Board shall consider all relevant factors specified in other sections of the ordinance and: (1) The danger to life and property due to increased flood heights or velocities caused by encroachments. (2) The danger that materials may be swept onto other lands or down stream to the injury of others. (3) The proposed water supply and sanitation systems and the ability of these systems to prevent disease, contamination, and unsanitary conditions. (4) The susceptibility of the proposed facility and its contents to flood damage and the effect of such damage to the individual owner. (5) The importance of the services provided by the proposed facility to the community. (6) The requirements of the facility for a flood plain location. (7) The availability of alternative locations not subject to flooding for the proposed use. (8) The compatibility of the proposed use with existing development and development anticipated in the foreseeable future. (9) The relationship of the proposed use to the comprehensive plan and flood plain management program for the area. (10) The safety of access to the property in times of flood for ordinary and emergency vehicles. (11) The expected heights, velocity, duration, rate of rise, and sediment transport of floodwater expected at the site. 3 (12) Such other factors which are relevant to the purpose of the ordinance. FINDINGS OF FACTS & CONCLUSIONS: Staff makes the following findings of facts: 1. The design of the structure predates the adoption of the City's flood plain regulations in 1980. 2. The finished floor of the existing structure meets the elevation requirements of 3 feet above base flood elevation. 3. The open garages under the structure are not elevated. However, the flood plain regulations (Section 9.5(2)(k)) allow parking areas and other "low damage potential storage" if the walls have sufficient openings to allow the free entry and exit of rising flood waters. The garages will not have doors. 4. All mechanical and electrical equipment e ill be ion or higher. h gh oved from the lower level and raised to 3 feet above the base S. All outdoor condenser units will be raised to 3 feet above base flood elevation by mounting on the exterior walls of the structure. 6. The entryways to the building are, themselves, below the elevation requirements. However, construction techniques will be of low damage potential. The lowest floor of the habitable space meets the elevation requirements. 7. The parking spaces under the structure preclude the ability to elevate to 18 feet around the perimeter of the structure. 8. Because of the design of the structure, the apartments have survived several flood events with only minimal damage. None of the previous flood damage rose to the level that required didldamagethe structure nce with ewel�beyond d plain regulations. However, the July 2 the 50 percent threshold. 9. The perimeter elevation requirements for a residential structure are intended to provide a safe evacuation area in the event of a flood event, allowing the residents to escape the structure but remain dry while awaiting rescue. In this neighborhood, however, neither S. 5'" Street itself, the driveways of all the apartments along S. 5t" Street, or most of the apartment buildings themselves t" are elevated to the base flood level. The water level over S. 5Street is estimated to be approximately 3 and one-half feet deep in a base flood event. During past major flooding events, unconventional methods such as front end loaders and boats have been needed to evacuatepeople alorom theng the S street. t Street apartments by navigating through turbulent flood ong 4 10. The requirement that the reconstructed building provide the perimeter elevation would result in the loss of 32 parking spaces under the building. It would also require the reconstruction of driveways that would interfere with the approved parking arrangements on the buildings to the west and east. It would also likely require driveways that are very steep as they approach S. 51h Street. 11. As an alternative to the perimeter elevation requirements, the owner proposes that the existing elevated garage be allowed to provide the necessary elevation. The garages place the finished floor of the structure at more than 3 feet above the base flood elevation. CONCLUSIONS: Access to the site in the event of a flood event is difficult for all the structures along S. 5th Street due to the elevation of the road. Both driveways and many of the apartment buildings themselves are also below the base flood elevation. The relief requested from the 18 foot distance requirement would not increase the risk that already exists. For there to be an effective means of accessing the site during flooding, S. 5th Street, itself, would need to be elevated. After an examination of the submitted plans and an evaluation of those plans as they pertain to the flood plain regulations, staff concludes that the criteria necessary for the approval of the Conditional Use Permit to Allow the Alternative Method of Elevation are met; that is, the use of the existing garages to meet the elevation requirement in lieu of the requirement that compacted fill be placed 18 feet around the perimeter of the structure to a minimum height of 3 feet above base flood elevation. If the Board approves the Conditional Use Permit and the accompanying Special Use Permit, the applicant will complete the necessary plans for a building permit. Staff will review those plans and building permit application to ensure compliance with all other aspects of the flood plain regulations prior to issuing a local Flood Plain Development Permit. ALTERNATIVES: 1. The Zoning Board of Adjustment can approve the Conditional Use Permit to Allow the Alternative Method of Elevation for the reconstruction of the multi-family housing at 301 S. 5th Street as shown on the site plan updated and submitted on November 8, 2012 by FOX Engineering and the architectural drawing updated and submitted on November 8, 2012 by Roseland Mackey Harris Architects based upon the findings and conclusions of staff. 2. The Zoning Board of Adjustment can deny the Conditional Use Permit to Allow the Alternative Method of Elevation for the reconstruction of the multi-family housing at 301 S. 5th Street as shown on the site plan updated and submitted on November 8, 2012 by FOX Engineering and the architectural drawing updated 5 and submitted on November 8, 2012 by Roseland Mackey Harris Architects if the Board determines that the proposed elevation results in unnecessary risk to residents or the other factors as noted in Section 9.7 of the flood plain regulations. 3. Action on this request can be postponed and referred back to City staff and/or the applicant for additional information. DEPARTMENT RECOMMENDATION: Based upon the Findings of Fact and Conclusions above, it is the recommendation of the Department of Planning and Housing that the Zoning Board of Adjustment approve the Conditional Use Permit to Allow the Alternative Method of Elevation for the reconstruction of the multi-family housing at 301 S. 5th Street as shown on the site plan updated and submitted on November 8, 2012 by FOX Engineering and the architectural drawing updated and submitted on November 8, 2012 by Roseland Mackey Harris Architects based upon the findings and conclusions of staff. SAPLAN_SWCouncil Boards Commissions\ZBA\Conditional Use in Floodway\301_S_5th_Rebuild_CUP_Alt_Elev-11-14-12.docx 6