Between 1990 and 2010 alone, while Seattle’s population grew 18 percent, the population in single-family-zoned areas outside urban villages, which “compris[e] 60 percent of Seattle’s total land area,” grew just three percent. (Those areas, again, are the parts of town where the proposed zoning changes would make it somewhat easier for homeowners to add an additional unit or two to their property.) Single-family areas, in other words, have not only failed to absorb an equitable proportion of the city’s growth, but they have managed this feat through the adoption of ever more restrictive zoning laws in Seattle’s relatively recent history.

Excluding new residents from single-family areas has had class and racial implications. According to the DEIS, people of color have become disproportionately more likely to live in areas zoned for multifamily use—that is, areas outside the single-family zones that Kaplan and the Queen Anne Community Council are suing to “protect”—with a few exceptions, including Southeast Seattle and the Central District. “Non-Hispanic White people are, by contrast, disproportionately likely to live in areas where single-family housing predominates.” Meanwhile, people of color are dramatically more likely to be renters rather than homeowners and more likely to spend more than 30 percent (or even 50 percent) of their income on housing than the non-Hispanic white folks who dominate single-family areas. Less than a third of all households of color, and fewer than 30 percent of Black and Hispanic/Latinx households, live in detached single-family houses, while more white people live in houses than any other housing type. According to the city’s analysis, “[T]hese citywide statistics illustrate that housing type varies along racial lines and are suggestive of patterns in single- family zones, where detached one-unit structures are the only housing type allowed.”

The DEIS also demolishes the notion—common among both wealthy homeowners like Kaplan and anti-displacement activists on the left—that allowing more housing in single-family areas will result in greater displacement of low-income people from those areas. (This theory was recently articulated by former Seattle City Council candidate Jon Grant, who claimed that “one of the largest portions of our affordable housing stock is single-family homes.”) According to the city’s analysis, although 54 percent of homes citywide are renter-occupied, just 27 percent of homes in the “study area” (single-family areas outside urban villages) are. Since the study area includes many apartments built before apartments were made illegal in those areas, it’s safe to assume that those rental units are mostly those apartments, not single-family houses.

Looking at the data another way, it’s clear that the people who do live in detached single-family houses are mostly well above Seattle’s area median income, which was around $75,000 in 2015 (and is closer to $80,000 now). The disparity is perhaps best illustrated with a couple of charts:

The report also spells it out: Most poor people don’t live in detached single-family houses, rental or otherwise, because they simply can’t afford them. “Only 14 percent of households in detached one-unit structures are below 200 percent of the poverty level, a common threshold to be eligible for certain assistance programs, while for most other housing types about one-third of households are below 200 percent of the poverty level,” the report concludes. Given that 81 percent of single-family homes are occupied by homeowners, not renters, that means that just 2.66 percent of all single-family houses are occupied by people making twice the poverty level or less. That doesn’t mean those renters can actually afford the houses they are renting; in fact, the city’s analysis found that a renter would have to make 123 percent of the Seattle area median income to afford an average single-family rental house, and that even the very rare low-rent houses are unaffordable to people making twice the federal poverty rate, or about $33,000 for family of two.

Put still another way: “For households with incomes of 80 percent of AMI, even two- or three-bedroom single-family homes with rents at the 25th percentile, a common marker of rent for the least expensive homes on the market, are out of reach.” In Seattle, in other words, essentially no single-family rental homes are affordable to very low-income renters.

The DEIS also, of course, looked into the specific environmental claims that are being made by the homeowners who want to ensure that backyard cottages remain effectively illegal in their neighborhoods. They found, not surprisingly, that neither of the two alternatives the city considered, which the city estimates would produce between 1,210 and 1,440 more attached and detached accessory dwelling units, combined, across the city in the next 10 years—would have a significant impact on tree canopy, overall density, parking availability, or neighborhood aesthetics. (Alternative 3, which includes more size restrictions on detached units and would require homeowners building a second accessory unit to contribute to the city’s Mandatory Housing Affordability program, would have slightly lower impacts in some areas, but the impact of 121 to 144 new units spread across the city would be generally negligible.) The report did note, however, that “removing the off-street parking requirement could reduce the amount of vegetation and tree removal otherwise needed to accommodate a parking space when creating an ADU.”

The city has been debating whether to allow more homeowners to build extra units for decades, and this specific proposal has been on the table since 2014, when the council adopted a resolution calling for a plan to “promot[e] workforce housing” by exploring ways to make building backyard cottages easier. This latest round will inevitably result in another challenge and more delays, illustrating just how hard it is to make even incremental zoning changes in Seattle. As long as homeowners believe sharing their prosperous neighborhoods with even a few newcomers will impact their property values, which continue to skyrocket year over year, even the most modest request that they participate in solving our affordability crisis will continue to be met with a barrage of legal challenges. By the time this legislation actually starts producing new housing for non-wealthy Seattle residents, it seems more likely than not that the median home in Seattle will have risen from its current high, around $820,000, to well over than a million dollars.