Permit Review Detail
Review Status: Completed
Review Details: FLOODPLAIN
Permit Number - T12OT01003
Review Name: FLOODPLAIN
Review Status: Completed
| Review Date | Reviewer's Name | Type of Review | Description | Status | Comments |
|---|---|---|---|---|---|
| 07/13/2012 | ELIZABETH LEIBOLD | ENGINEERING | REVIEW | Denied | DATE: July 13, 2012 TO: Jeff Stanley, P.E. SUBJECT: New Single-Family Residence - Engineering Preliminary Floodplain Review LOCATION: 8878 E WOODLAND RD, Ward 2, T14S R15E Section3 REVIEWER: Elizabeth Leibold, P.E., CPM, CFM ACTIVITY NUMBERS: T12OT01003 (Floodplain review) SUMMARY: Engineering Division of Development Services Department provides the following preliminary floodplain review comments. The applicant acknowledged that the submittal was for feasibility since the package was determined to be incomplete. At this time, no information is being provided for elevation certificate requirements or other basic drainage criteria. The following information for this proposed project is provided for consideration: Preliminary Floodplain Comments and Considerations for Feasibility: 1) Tucson Code Sec.26-5. Areas designated as floodways have a high potential for flooding and land in the floodway should be set aside for the conveyance of floodwaters as a first priority. Typically, new structures proposed within regional watercourses, especially residential structures, are difficult to develop due to the high risks of floodplain and erosion hazards and the associated engineering requirements to assure safety. Proceeding with the proposed development is not recommended by the City of Tucson PDSD Engineering Division. 2) DS Sec.10-02.7.6.1: An additional concern for this proposed project is the impact of the erosion hazard setback for the parcel. The minimum EHS is defined using the regional watercourse equations in the Drainage Manual and indicate from a very preliminary calculation (using eqn 7.7a, assuming straight section) to encompass the proposed house. The City of Tucson could not approve a residential structure within the erosion hazard setback to a regional watercourse without showing erosion hazard protection which is typically cost prohibitive for these types of developments since large scour / erosion protection structures are typically needed. 3) LUC 2.8.6: This project falls within the scope of an ERZ Report requirement. ERZ Report and processing is required. 4) Tucson Code Sec.26-8(d)(2): No fill shall be placed in any floodway; so, unless existing topography has a building site high enough that no additional fill is needed, and complies with floodplain regulations, project may not be approvable. 5) TC Sec.26-11.2.2.e: The submittal only provided a HEC-2 analysis from 1991 which may have outdated flood data and does not match current FEMA datum or current topographic data. No grading plan was submitted to determine other feasibility criteria. Per Sec.26-5.2(e): development in the floodway fringe shall not increase the base flood elevation more than one-tenth of a foot. The proposed elevation data in the letter which was submitted for this project indicates a WSEL of 2581.81 and a ground elevation of 2527.78, yet the existing CITY GIS contour lines are showing an approximate elevation of 2530 for this parcel and from the current FEMA Digital FIRM data, FEMA WSEL's adjacent to this parcel, downstream and upstream respectively, are 2531 and 2533 (NAVD88). The engineering study should clarify discrepancies in elevations and address the requirements outlined in section 26-5.2. A FEMA LOMC submittal would be warranted for changing the flood zone status to alleviate flood insurance and revised the floodway and/or floodplain limits may be needed. Additional comprehensive engineering study prepared by a state-registered professional civil engineer for the purpose of evaluating possible flood hazards and shall include consideration of the effects of the development on flood heights, water velocities, direction of flow, sedimentation and erosion, volume of flows, type of channel banks and other items that may be pertinent, and the resultant effects on structures, land, banks, etc., for the adjacent regulatory floodplain and the surrounding area. 6) Tucson Code Sec.26-11.2(b)(1) No discussion of sanitary sewer design was provided. Note that septic systems are typically not approved in floodplains let alone floodways. Please call to discuss, 837-4934. Elizabeth Leibold, P.E., CPM, CFM Civil Engineer Engineering Division Development Services Department City of Tucson |
Final Status
| Task End Date | Reviewer's Name | Type of Review | Description |
|---|---|---|---|
| 07/18/2012 | CPIERCE1 | OUT TO CUSTOMER | Completed |