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Atlas 14 – Commercial Redevelopment Exception Watershed Protection Department Codes and Ordinances Joint Committee | June 15, 2022 Floodplain Regulations Update What floodplain rules did we update? What floodplain rules do we recommend updating now? 2 What floodplain rules did we update? Most significant update to our floodplain rules in their 36-year history Goal of updated rules: Protect our residents from flooding based on a better understanding of flood risk with new rainfall information Updated four basic elements of rules • Floodplain definitions • Residential redevelopment exception • Colorado River exception • Freeboard 3 Floodplain Definitions Regulatory 100-yr floodplain = Current FEMA 500-yr floodplain Regulatory 25-yr floodplain = Old COA 100-yr floodplain • Maintain the City’s level of flood protection • Limit construction of new buildings in areas with known flood risk during re- mapping process • Interim definitions until floodplains are re-mapped in 2 - 3 years 4 Residential Redevelopment Exception Administrative approval process floodplain if: 1. Replacement or modification of an existing residential building 2. Does not increase number of dwelling units 3. Finished floor elevation is at least 2 feet above the 100-year floodplain 4. No adverse flooding impact If these 4 conditions are met, the safe access requirement is waived Purpose • Incentivizes development that decreases flood risk • 80% of buildings in the 100-year floodplain are residential • Doesn’t increase the number of dwelling units at risk of flooding • Opens up opportunity for grant Existing condition Re-developed condition funding 5 Option for Minor Improvements to Residential Buildings Administrative approval process for an addition to a residential building in the floodplain if: 1. Finished floor elevation of the addition is at least 2 feet above the 100-year floodplain 2. Not a substantial improvement 3. No adverse flooding impact If these 3 conditions are met, the safe access requirement is waived 6 Colorado River Exception The previous exception allowed for a building to encroach in the 100-year floodplain if it was: • Downstream of Longhorn Dam • Along Lady Bird Lake New rule expands this exception to include: • Lake Austin • Lake Travis (within COA jurisdiction) Lake Travis Purpose • Provide uniform regulations along Colorado River • Colorado River flooding is not flash flooding like rest of City Lake Austin Lady Bird Lake Colorado River downstream of Longhorn Dam 7 7 Freeboard Increase the minimum height between a building’s finished floor and the 100-year floodplain from 1 ft to 2 ft Intent • Freeboard is the single-most effective means for reducing flood risk to a building in the floodplain • Reduces flood insurance premiums 8 Result of Collaborative Code Revision Process Contacted more than 2,700 people at 110 different meetings City Council approved the new rules on November 14, 2019 Staff pledged to develop draft rules regarding commercial redevelopment 9 What floodplain rules do we recommend updating now? Commercial Redevelopment Exception 10 Commercial Redevelopment exception Goal: Create an administrative approval process for commercial redevelopment that decreases flood risk compared to the existing conditions Considerations: Building use; square footage; occupant load; parking flood risk; building height 11 Proposed commercial redevelopment exception Administrative approval process for a commercial building in the floodplain if: 1. Replaces or modifies an existing commercial building 2. Finished floor elevation is at least 2 feet above the 100-year floodplain 4. Does not include the following uses: E (Educational); F (Factory); H (High Hazard); or I (Institutional) 5. Does not increase the number or flood level of parking spaces within the floodplain on the property unless otherwise required; and 3. Does not increase the building square 6. No adverse flooding impact footage on the property If these conditions are met, the safe access requirement is waived 12 Proposed commercial redevelopment exception example: Existing conditions 14 spaces in floodplain with maximum depth of 14 inches 14 spaces outside floodplain 5,000 sq. ft. building; Assembly use; 13 Proposed commercial redevelopment exception example: Option 1: same configuration 14 spaces in floodplain with maximum depth of 14 inches 14 spaces outside floodplain 5,000 sq. ft. building; Assembly use; 14 Proposed commercial redevelopment exception example: Option 2: reconfiguration 14 spaces in floodplain with maximum depth of 14 inches 4 spaces outside floodplain 5,000 sq. ft. building; Assembly use; 15 Process to approval • Codes and Ordinances Joint • Codes and Ordinances Joint Committee Committee • Planning Commission • Zoning and Platting Commission • Environmental Commission • Planning Commission ❖ Request recommendation to City Council • City Council • Building and Fire Code Board of Appeals 16 Atlas 14 – Commercial Redevelopment Exception