https://nathenry.com/writing/2023-02-07-seattle-walkability.html Nat Henry | Writing * Portfolio * Writing * Bio * Contact * RSS [post_heade] Is Seattle a 15-minute city? It depends on where you want to walk This could be a pivotal year for mobility in Seattle. In the final week of January, Seattle won $25.7 million in federal grants to build safer streets, made transit free for 10,000 Seattle Housing Authority residents, and solicited public feedback on a major update to the city's Comprehensive Plan. To transform this momentum into meaningful change, we need a catalyst--a coherent, powerful vision for moving around Seattle. Consider the 15-minute city: first imagined by Carlos Moreno and most fully realized (so far) in Paris, this model describes a metropolis where residents can satisfy the full spectrum of their daily needs within a 15-minute walk or bike ride. A diagram showing amenities that should be accessible in the 15-minute city. Concept diagram of the 15-minute city. Source: @re_visionuk The 15-minute city could be a compelling target for the future of mobility in Seattle, and some of our elected officials have expressed interest in the possibility. To better understand how Seattle might become a 15-minute city, I created an interactive map showing walking times to amenities across the city. These include: * Supermarkets * Public libraries * Parks that are 20,000 square feet or larger (excluding "pocket parks") * Bus stops connecting directly to downtown Seattle * Light rail stations * Restaurants and coffee shops * Public schools, split by grade level Select amenities from the check boxes below to automatically update the map. The color shown for each block represents the maximum walking time across all selected amenities. You can pan and zoom on the map; hover over a block or tap on mobile to see specific travel times. By combining travel time data with the population of each block, we can count how many Seattleites are less than a 15-minute walk from each class of amenity: Service Access (citywide) Parks >99% Bus stops connecting to downtown 97% Restaurants 91% Coffee shops 90% Groceries 73% Elementary schools 62% Libraries 49% Link stops 27% Middle schools 18% High schools 15% Credit where credit is due: it's great that over 99% of residents have walking access to a public park, and 97% have walking access to a direct bus downtown. On a less impressive note, it will surprise no one that light rail stations are not walkable for most Seattle residents. Middle and high schools are walkable for less than 20% of Seattleites due to their size and placement in less-dense neighborhoods. To check how closely neighborhoods of Seattle match the 15-minute city model, we can count how many residents have full walking access to combinations of amenities: * Standard: 15-minute walking access to a supermarket, a public library, a public park, a bus stop to downtown, a restaurant, and a coffee shop * Standard + Link: Access to all of the "standard" amenities plus a light rail stop * Standard + Elementary School: Access to all of the "standard" amenities plus an elementary school. Possibly suitable for a family with young children. * Standard + High School: Access to all of the "standard" amenities plus a high school. Possibly suitable for a family with teenaged children. Neighborhood Pop. Standard S + S + S + Link Elem. High Citywide 737,000 44% 21% 27% 9% Downtown (CBD) 5,300 >99% >99% 0% 0% International District 4,500 >99% 97% >99% 0% Pioneer Square 4,400 >99% >99% 35% 0% Pike Place Market 3,300 97% 97% 0% 0% Ballard: Adams 15,800 97% 0% 63% 37% Capitol Hill: Broadway 28,100 94% 91% 82% 0% South Lake Union 12,400 92% 42% 5% 0% Madrona 4,100 91% 0% 91% 15% Green Lake 10,300 84% 44% 83% 31% Central District: Atlantic 8,700 83% 2% 83% 48% First Hill 13,600 81% 81% 15% 0% Beacon Hill: New Holly 4,900 81% 66% 81% 0% Belltown 24,300 78% 78% 0% 0% University District 34,400 78% 77% 2% 14% Queen Anne: West 7,500 77% 0% 70% 0% Wallingford 18,500 76% 9% 21% 49% Beacon Hill: North 12,800 76% 71% 76% 11% Fremont 14,800 73% 0% 71% 31% Lake City: Cedar Park 6,500 71% 0% 0% 2% Central District: Mann 5,200 71% 0% 65% 53% Yesler Terrace 5,400 67% 67% 67% 0% Roosevelt 9,000 61% 44% 40% 42% W. Seattle: N. Admiral 13,600 61% 0% 54% 44% Columbia City 15,100 60% 54% 34% 2% Rainier Valley: Dunlap 6,400 58% 42% 58% 58% Delridge: Roxhill 4,300 56% 0% 39% 40% Greenwood 18,200 56% 0% 50% 0% Northeast: Bryant 5,600 53% 0% 53% 0% Leschi 5,800 52% 0% 52% 36% W. Seattle: Fairmount Park 7,700 45% 0% 45% 0% Central District: Minor 11,400 44% 0% 38% 44% Bitter Lake 10,200 42% 0% 41% 7% Queen Anne: East 9,800 39% 0% 31% 0% Pinehurst 8,400 39% 13% 15% 0% Lake City: Victory Hts. 5,900 38% 0% 13% 12% Magnolia: Southeast 5,500 37% 0% 37% 0% Maple Leaf 11,500 36% 31% 25% 0% Ballard: West Woodland 8,100 36% 0% 25% 26% Ravenna 12,800 36% 2% 31% 3% Magnolia: Briarcliff 5,900 33% 0% 33% 0% Lake City: Olympic Hills 9,500 32% 0% 28% 0% Rainier Beach 6,900 31% 11% 31% 18% Queen Anne: North 12,200 29% 0% 11% 0% Phinney Ridge 10,400 27% 0% 22% 0% SoDo/Industrial District 1,100 25% 25% 12% 0% Wedgwood 9,300 24% 0% 24% 0% Magnolia: Lawton Park 9,800 21% 0% 20% 0% Beacon Hill: South 5,400 21% 19% 21% 0% Rainier Valley: Brighton 8,900 20% 20% 20% 0% Uptown 14,200 20% 0% 16% 0% View Ridge 5,700 19% 0% 19% 0% Delridge: Highland Park 6,700 18% 0% 18% 0% Mount Baker 8,300 18% 8% 18% 7% Beacon Hill: Mid-Beacon 13,800 17% 12% 15% 0% Hill W. Seattle: Gatewood 6,900 17% 0% 17% 0% Broadview 8,600 16% 0% 16% 0% Stevens 12,100 15% 14% 15% 0% Delridge: High Point 8,300 15% 0% 15% 0% Lake City: Meadowbrook 3,500 14% 0% 0% 6% W. Seattle: Seaview 5,000 13% 0% 11% 0% Whittier Heights 5,700 13% 0% 13% 0% Loyal Heights 8,700 13% 0% 13% 13% Harrison/Denny-Blaine 2,700 11% 0% 10% 0% Delridge: South 6,600 10% 0% 9% 5% W. Seattle: Fauntleroy 5,700 9% 0% 7% 0% Seward Park 7,100 3% 0% 1% 0% Sunset Hill 6,000 2% 0% 2% 0% W. Seattle: Arbor Heights 5,400 2% 0% 2% 0% Matthews Beach 6,600 2% 0% 0% 2% South Park 3,700 1% 0% 1% 0% Northgate: Haller Lake 8,800 1% 0% 0% 1% Northgate: N. College Park 7,500 0% 0% 0% 0% North Beach/Blue Ridge 5,700 0% 0% 0% 0% Crown Hill 5,200 0% 0% 0% 0% Sand Point 700 0% 0% 0% 0% Windermere 4,900 0% 0% 0% 0% Laurelhurst 4,900 0% 0% 0% 0% Interbay 2,300 0% 0% 0% 0% Portage Bay 1,500 0% 0% 0% 0% Eastlake 5,200 0% 0% 0% 0% Montlake 4,700 0% 0% 0% 0% Madison Park 4,600 0% 0% 0% 0% Westlake 4,000 0% 0% 0% 0% W. Seattle: Alki 7,200 0% 0% 0% 0% W. Seattle: Genesee 9,100 0% 0% 0% 0% Delridge: North 4,900 0% 0% 0% 0% Delridge: Riverview 4,200 0% 0% 0% 0% Georgetown 1,400 0% 0% 0% 0% Rainier View 4,000 0% 0% 0% 0% Despite Seattle's high rankings on conventional walking metrics, only 44% of Seattleites can walk to basic city amenities. Seattle as a whole would need major changes to fulfill the vision of a 15-minute city. Of the 89 neighborhoods considered, only nine are "15-minute neighborhoods" walkable for 90% or more of their residents. On the other end of the spectrum, 27 neighborhoods--including large portions of West Seattle, Delridge, and Northeast Seattle--are extremely unwalkable, with less than 10% of their residents able to walk to basic amenities. Seattle has a range of walkable neighborhoods with elementary schools, stretching from North Admiral in West Seattle to Bryant in the northeast. Parents of teenagers have far fewer options: only the Mann and Dunlap neighborhoods offer most of their residents walking access both to nearby high schools (Garfield High and Rainier Beach High, respectively) as well as to basic city amenities. In some neighborhoods, including Loyal Heights, Mid-Beacon Hill, and South Park, walkability is one well-placed library or grocery store away. However, in most areas with very low walkability, building more accessible neighborhoods may require fundamental shifts to the distribution of housing and services across the city. We might be able to chart a way forward by focusing on walkability at the block level. Blocks with 15-minute walking access to basic amenities extend far beyond the boundaries of the "Urban Villages" targeted in Seattle's previous Comprehensive Plans. These pockets of walkability could be the starting point for targeting more inclusive growth across the city. For those who think that a 15-minute city is still a worthy vision for Seattle, I hope this map is a useful tool to turn momentum into action. --------------------------------------------------------------------- Postscript: Technical details Population by block came from the 2020 US Census. Shapefiles for city blocks and bodies of water came from the US Census TIGER/Line shapefiles. Blocks listed as having zero population in the 2020 Census were not displayed on the interactive map. I pulled destination locations from a few sources: * Supermarkets: Pulled prospective supermarket locations from OpenStreetMap (OSM) using the Overpass API, filtered using the "supermarket" and "convenience" tags. I then reviewed the prospective locations using Google Maps, dropping closed locations, convenience stores, mini markets, and specialty stores. My heuristics for including a store as a supermarket were (a) two or more display rows dedicated to fresh produce and (b) two or more aisles dedicated to household goods such as cleaning supplies or toiletries. I manually added the Costco on 4th Ave S, which OpenStreetMaps had listed as a wholesale store. A limitation of this analysis is that high-end grocery stores may not be affordable to many of the people who live within walking distance. * Public libraries: Downloaded from the King County Open GIS Portal * Parks: Downloaded from the City of Seattle Open GIS Portal and subset to parks with an area greater than 20,000 square feet * Bus stops and light rail: Downloaded from the King County Open GIS Portal. Light rail stops were filtered using the route number. To determine the transit routes that passed through Downtown Seattle, I used the transit schedules from the King County Metro website. * Restaurants: Pulled from OSM, filtered using the "restaurant" tag * Coffee shops: Pulled from OSM, filtered using the "coffee" and "cafe" tags * Schools: Downloaded from the King County Open GIS Portal and subset to public schools in Seattle. K-8 schools are coded as both elementary and middle schools. For some alternative public schools with multiple locations, I hand-coded all locations listed on their website. Edit 8 Feb 2023: Thanks to Twitter users who pointed out that this dataset was missing Lincoln High School! I have manually added it to the list of high schools and re-created the map and tables. For all destinations except for public libraries, parks, and schools, I used a geographic filter that extended beyond Seattle's borders to account for destinations slightly outside the city. Data was pulled throughout 2022 so may be a few months out of date at the time of writing. I calculated all walking times from blocks to amenities using OpenRouteService, which relies on street network data from OpenStreetMap. Origin points were the centroid of each block. The routing tool uses a walking speed of 5 kilometers per hour, or about 3 miles per hour. I found all origin-destination combinations that were less than 2.5 km apart as the crow flies, then calculated actual walking time for each candidate pair using a locally-hosted instance of the OpenRouteService Matrix API. For each block, the final travel time to an amenity is the shortest travel time to any destination in that amenity category. For the final table of results, I used the neighborhood boundaries published by the Office of the Seattle City Clerk. If you take issue with the neighborhood boundaries, I defer to the Office of the Clerk and their disclaimer :) --------------------------------------------------------------------- Have questions or comments? Let me know!