Policy Memorandum Tropical Dense[city]:Transit-Oriented Hyperdensity in Miami: Year 2100 Kenner N. Carmody, M.Des Energy & Environments 2019 Problem: This research aims to visualize and better understand future required housing stock necessary to accommodate displaced populations in Miami’s Allapattah neighborhood affected by sea level rise and resultant tidal inundation by the year 2100 (NOAA Office for Coastal Management). Property data, local geography and NOAA sea-level rise projections within this time-scale are used in order to propose greater density in Miami due to lost surface area. This study evaluates the existing spatial capacity and density distribution under current zoning policy, Miami 21. This study reveals that the current zoning code, overlay districts, and Neighborhood Development Zones (NDZ) within the population catchment area of Allapattah are maladaptive. - The spatial analysis in this research assumes a residential occupancy of 1 person per 450 square feet (41.8m2), and floor to floor heights of 14’-0” (4.2m). - The criteria for this displacement assumes intracity relocation within Miami’s urban core, and excludes populations affected outside of the target study area of Allapattah. - This model assumes relocation within a population catchment area in Allapattah at elevations of 6’-0” above sea level and assumes density increases along Miami’s legacy Metrorail system. - This study excludes future population growth from the required future housing scenario. Figures Housing: - Total Population in Allapattah: 58,978 (2010 Census Data); 62,929 (2017 Estimate) - Total Housing Units: 22,255 - Unit Mix: Studio: 3% 1-Bedroom: 8%; 2-Bedroom: 35%; 3-Bedroom: 20%; 4-Bedroom: 17%; 5-Bedroom: 7%; 6-Bedroom: 4%; > 6% - The majority of housing stock in Allapattah predates 1975 and is poorly suited to its geography and climate. - 80% of Allapattah Residents are renters Findings Housing: - Highest population densities in Allapattah are located in low-lying areas - Investment criteria for NDZ’s supported by the City of Miami are located in low-lying areas - Economically challenged Seniors will be disproportionately affected (single, widowed with modest education), housed in low-lying areas - Potential number of displaced population from tidal flooding & sea level rise (NOAA 2100 Projection): 9,661 - Potential number of required New Housing Units (NOAA 2100 Projection): 4,089 - Unit Mix of Affected Housing: 7% 1-Bedroom: 21%; 2-Bedroom: 27%; 3-Bedroom: 13%; 4-Bedroom: 11%; 5-Bedroom: 5%; 6-Bedroom: 4%; > 10% The above figures double in 10-years’ time, from 2100 to 2110 based on NOAA Projection with zero carbon emissions reduction - Potential number of displaced population (NOAA 2110 Projection, no carbon emissions reduction): 22,156 - Potential number of required New Units (NOAA 2110 Projection, no carbon emissions reduction): 8,700 Figures Transit: - Average Model Split for Ridership along Miami Metrorail is ~25% with Metrobus making majority at ~65% - Average Weekday ridership for Allapattah and Santa Clara Station is 1,751 and 732 respectively (Sep 2017 Report) Recommendations: - Miami must develop a Transfer of Development Rights model to diffuse low-lying zones in Allapattah while densifying on high(er) elevations near mass-transit. This model must allow non-contiguous developments to trade densities between vulnerable and more stable areas. - Metrorail in Miami is underutilized compared to Metrobus ridership. With current bridge elevations at only 1-1.5ft above sea-level (e.g. from Miami to Miami Beach) moving a greater share of ridership to Metrorail and densifying housing, jobs and amenities along Metrorail transit corridors would be an adaptive solution for the City of Miami - Allapattah consists of mostly small parcels. However, a number of large parcels exist for initial densification – with gradual densification occurring over time between Allapattah and Santa Clara Metrorail Stations along major north/south axes. - Relocation through Transfer Development Rights that allows for down-zoning of high risk geographies, the up-zoning of low-risk geographies and that incentivizes management of stormwater are key principles in realizing an equitable, mobility oriented, and hyper-dense future for Allapattah and Miami. Through TDR and hyperdense development, of the 22,150 people affected, 23,070 may be rehoused in the following developments within Allapattah, so called Allapattah (at Allapattah Station), Bridging Zone (Between Allapattah and Santa Clara Stations), and Santa Clara (located in rezoned D2 Industrial Zone). ALLAPATTAH HYPER-DENSITY ZONE AVG FAR: 6 Retail Area: 22,870 ft2 Residential Area: 61,838 ft2 ; Population: 1,536 Max Height: 220ft / 20 Floors BRIDGING ZONE AVG FAR: 2.66 Retail Area: 55, 946 ft2 Residential Area: 1721084 ft2 ; Population: 3,854 Max Height: 90ft / 8 Floors SANTA CLARA HYPER-DENSITY ZONE AVG FAR: 5.5 Retail Area: 5,920,150 ft2 Residential Area: 7,628,060 ft2 ; Population: 17,680 Max Height: 350ft / 30 Floors Total Housed: 23,070 Conclusion: Sited along Miami’s legacy metro system, a densification proposition in East Allapattah tests a hypothesis that a densified urban zone along underutilized existing transit infrastructure can accommodate new (and equitable) densities in Allapattah where housing, employment and amenities can cluster. If Miami is to have a future, this project will be only one of many to house the millions of people that will be affected by sea-level inundation and tidal flooding in South Florida. Identifying additional potential zones for substantial densification and diffusion in an amendment to Miami’s land use planning and zoning code is paramount. Newly densified zones can and should be located along Miami’s existing transit infrastructure with additional expansion to other high ground to support a diversifying economy and growing city. Decreasing land available for suburban development in South Florida will mean both existing populations and future population growth will inevitably cluster in new urban centers if the city is to mitigate disinvestment and the resultant decline by the end of the century or sooner. Strategic high-density development is critical for Miami’s ecological and economic viability in the 21st century. Tropical Dense[city]: Transit-Oriented Hyperdensity in Miami: Year 2100 Kenner N. Carmody MDes, Energy & Environments 2019 What do we know? The capacity for housing and transportation unites in Allapattah. What do we suspect? Climate gentrification will accelerate disruption and speculation in Allapattah. How might we act? We need to plan for responsible (and inevitable) density for vulnerable and displaced households. Brownsville Future Brightline Route Housing and transit unify in Allapattah. Seen here with Miami’s Metrorail system highlighted in yeloow, Allapattah is now subject Earlington Heights to immense economic, social pressures and land speculation. Allapattah These pressures will intensify due to of sea level rise and resultant climate gentrification in the coming years ALLAPATTAH However, with appropriately Santa Clara revised zoning codes, long-term land use planning and economic incentives to achieve these plans, Convention Center equitable outcomes are possible for Miami’s most vulnerable Culmer populations in the city’s urban center. Historic Overtown/ Lyric Theatre WEST LITTLE HAVANA Government Center EAST LITTLE HAVANA Brickell Vizcaya Coconut Grove Brownsville Most of Allapattah’s population is currently located in the neighborhood’s most vulnerable Earlington Heights areas along the Miami River and low-lying areas in the northeastern Allapattah portion of the district (highlighted in blue). These populations must be relocated to higher geography on the east side of the district. ALLAPATTAH Santa Clara Convention Center Culmer Historic Overtown/ OVERTOWN Lyric Theatre WEST LITTLE HAVANA Government Center EAST LITTLE HAVANA POPULATION DENSITIES 2010* Brickell Symbol Range 2 - 532 533 - 1235 Vizcaya 1236 - 1704 1705 - 2175 2176 - 3566 Coconut Grove *Values taken from 2010 US Census Block Data Most of Allapattah’s population is currently located in the neighborhood’s most vulnerable areas along the Miami River and low-lying areas in the northeastern portion of the district (highlighted in blue). These populations must be relocated to higher geography on the east side of the district. Using the NOAA Sea Level Rise model, the flooded areas of Allapattah, Overtown, and Little Havana are shown below. POPULATION DENSITIES 2010* Symbol Range 2 - 532 533 - 1235 1236 - 1704 1705 - 2175 2176 - 3566 *Values taken from 2010 US Census Block Data The necessity for relocation is obvious in this flooding scenario. The city will need to incentivize adaptation and flood mitigation over time to facilitate relocation over time. POPULATION DENSITIES 2010* Symbol Range 2 - 532 533 - 1235 1236 - 1704 1705 - 2175 2176 - 3566 *Values taken from 2010 US Census Block Data There is co-benefit of relocation to Earlington Heights higher ground in Allapattah. Higher geography in Allapattah coincides with Miami’s legacy Metrorail transit system. Incentivizing Allapattah transit oriented development on high ground will help facilitate transition in Allapattah and allow for higher future densities in the district. POPULATION DENSITIES 2010* Symbol Range 2 - 532 533 - 1235 Santa Clara 1236 - 1704 1705 - 2175 2176 - 3566 *Values taken from 2010 US Census Block Data Convention Center Culmer Historic Overtown/ Lyric Theatre Government Center Adopted in 2010,