# Modeling the Health Benefits of Superblocks across the City of Los Angeles
## 4 Discussion  
The LA Superblocks Model proposed in this study prioritized the potential Superblock locations in the City of LA with the help of the five data-driven rules. Defined by these five rules, we used the term Superblocks to refer to a sufficiently large urban area surrounded by major streets or arteries. In order to allow that at least one local street runs between the local main streets and the arteries that border the Superblocks, previous studies have established quantitative standards such as: (1) the minimum schematic expression of Superblocks with local traversing main streets is a 3 \(\times\) 3 street grid with four internal blocks; and (2) the minimum schematic expression of Superblocks with additional internal streets is a 5 \(\times\) 5 street grid with 16 internal blocks [28]. Thus, a generalizable Superblocks model must include size in its design. In this LA Superblocks Model, we chose 100,000 square feet and 12 road segments as the thresholds to filter the Superblock candidates to ensure the minimum schematic expression of the Superblocks in the model is greater than a 3 \(\times\) 3 street grid. However, we suggest future investigations into different types of schematic expression of Superblocks to extend this model to other metropolises. Figure 5: Annual ln($) saved from hospital admissions avoided due to air pollutant reductions that could accompany the five Superblocks scenarios. Urban transformation could be more challenging in cities that have considerably transformed streets and pedestrian streets such as the City of LA [29]. Thus, implementing Superblocks in existing residential areas may be a less-disruptive strategy to start such an urban transformation. Because residential areas not only carry less responsibilities for traffic circulation but also are major sources of the residents' ambient air pollution exposures, they offer good opportunities for implementing Superblocks. After examining the health and economic benefits of five different scenarios by transforming 5-50% of the residential areas in the City of LA, we found that transforming 30% of the residential areas offered the largest improvements in terms of health and economic benefits. Even though implementing more Superblocks into residential areas will provide greater health and economic benefits, the rate of increase slows with further transformation. For example, in the LA Superblocks Model, the minimum schematic expression of Superblocks and the requirements of major streets or arteries on the edge of Superblocks suggest that the maximum percentage should be \(\leq\)54.8%. More importantly, we found the marginal benefits became imperceptible after 30%. This latter benchmark helps to frame the scale of the Superblock implementation and the accompanying health benefits. This benchmark is very important, because there are various types of political barriers that could hamper the development of Superblocks. For example, in cities with both local and regional traffic, the implementation of Superblocks could lead to increased regional traffic congestion. In this sense, coordinated efforts between the various municipalities in the region are required [30]. Our identified scenarios can help planners and decision-makers in balancing the effectiveness of Superblocks in relation to major changes in physical activity or social cohesion and the possible political barriers and possible negative effects on traffic congestion. After being introduced in the City of Barcelona, many positive changes were observed in pedestrian mobility, air and noise pollution and the general perception of the neighborhood. Since then, researchers have conducted qualitative studies and surveys to analyze residents' perception of these effects by using various focus groups that are more or less likely to use the Superblocks based on the participants characteristics [22]. In this study, we used the slow streets and al fresco dining programs to anticipate residents' favorable perceptions of Superblocks in order to evaluate the impact of Superblocks.