Yesterday, the City of Seattle published the final Environmental Impact Statement for its citywide Mandatory Housing Affordability (MHA) rezone proposal. Citywide MHA is the key to the “Grand Bargain” at the center of the city’s Housing Affordability and Livability Agenda (HALA). In a nutshell, Citywide MHA would upzone many of the more urban parts of Seattle, in exchange for requiring developers in the upzoned areas to build (or pay for) a modestly higher amount of affordable housing as part of their projects.

The city describes the key objective of Citywide MHA as “increasing housing and jobs near frequent transit.” That’s a laudable goal, and absolutely necessary for the city’s continued growth. Many of Seattle’s roads are at capacity and we don’t have room for more. Geometry requires that further transportation capacity must come from transit, walking, or cycling. People only use transit if it’s easily accessible to them. Allowing more people to live near frequent transit will boost both transit ridership and total transportation capacity. For that reason and also for the affordable units it will generate, Citywide MHA is a positive step that we should support.

But it doesn’t go nearly far enough. We have the transit infrastructure to support much more housing than Citywide MHA anticipates, and thereby accommodate more of our new arrivals with less displacement of existing residents. Given the crisis of unaffordable housing prices in Seattle, we owe it to ourselves to do so.

Our transit infrastructure is much better than it was just three years ago, because city residents stepped to the plate. Seventy percent of city voters approved Sound Transit 3. When King County voters rejected a 2014 bus service measure, Seattle voters plunged into the breach, decisively approving their own. Bus restructures accompanying Link light rail brought even more frequent transit. SDOT’s report on the first two years of Proposition 1 has an amazing map (at left) showing the improvement. (We’ll have more to say about this Monday.)

And that’s not all. If funding allows, Metro wants to add yet more frequent corridors in connection with future Link openings. By 2040, Metro would blanket nearly the entire city in frequent service, as shown at right.

But Citywide MHA takes relatively little of this into account. A plan to “maximize housing and jobs near frequent transit” ought to upzone all along these frequent transit routes. Instead, the city’s interactive map shows lots of places directly on current or future frequent transit that remain stubbornly single-family. These areas ought to be upzoned too.

The case of Northeast Seattle is particularly instructive. A combination of a Link restructure and substantial city funding created two amazing frequent corridors along Roosevelt Way (route 67) and 35th Ave NE (route 65). These corridors now have buses running every 10 minutes, six days a week, and every 15 minutes until late at night. But the map shows how little Citywide MHA changes along the corridors (highlighted in yellow). There is barely any increased zoning, and lots of territory directly along the routes remains stubbornly single-family. Frequent transit capacity will go to waste.

A look at the Citywide MHA map reveals many other corridors throughout the city that have similar potential. Corridors like route 36 along Beacon Av S, route 62 in View Ridge, and RapidRide C in Fauntleroy represent potential opportunities for people to live car-free. All frequent transit corridors should have much more color on the map. Even after Citywide MHA takes the first baby steps, the city should keep moving further, so we can make the most of our newly expanding frequent transit network.