Two arguments in the debate over LOS have emerged. One calls for abandoning LOS but replacing it with a metric that prioritizes transit, cycling, and walking before cars, assuming that three decades of legal precedent would require some replacement metric. Another argues for walking away from LOS entirely, given that it is merely a convention and not a law.
Shortly after releasing the report on LOS deficiencies, the San Francisco County Transportation Authority (TA) convened a strategic working group in the spring of 2004 comprised of the Planning Department’s Office of Major Environmental Assessment (MEA), the MTA, user advocacy group representatives, and industry practitioners. The working group developed a replacement for LOS analysis that became known as auto trip generation, or ATG (PDF ).
ATG avoids intersection-specific analysis, instead evaluating new developments based on the number of car trips they would add to the aggregate traffic picture and assessing a transit mitigation fee based on the total number of additional trips. The working group debated for some over the threshold number of trips that would trigger the mitigation. Given that San Francisco is lined on three sides by water and is essentially built out to capacity, any new development that adds vehicle trips to the matrix will have an impact on overall traffic, so the threshold they decided on is one trip.
As Rachel Hiatt, senior transportation planner for the TA, reported at Transportation Research Board in 2005 (PDF ):
The Transit First policy of the City Charter recognizes that some short-term auto congestion is a predictable and unavoidable consequence of implementing Transit First policies, since mode shift will occur gradually as the transit, bicycle and pedestrian networks are improved. A measure of auto delay – auto LOS – is inconsistent with the Transit First policy for this reason. A measure of auto trips generated, in contrast, recognizes that adding additional automobile trips to San Francisco streets is environmentally undesirable, while allowing for automobile congestion impacts that may result from improving the city’s networks for transit, walking, and cycling.
The genius of ATG is that transit, bicycling and pedestrian improvements by definition will not add auto trips to traffic. Similarly, projects that remove space for cars and give them to buses, bikes, or people would no longer be considered to have a significant environmental impact under LOS analysis and would not be rejected outright because of inconvenience to drivers.
ATG flips the politics of mobility on its head and says the onus is on automobility to prove that it doesn’t disrupt the convenience of transit and non-polluting modes, nor that it decreases the livability of neighborhoods.
Though ATG has generally been accepted by the agencies involved in the working group, the devil is still in the details, especially on how to develop the transit impact mitigation fees. Ideally, the fees assessed for each ATG in a project would go directly to transit, bicycling, and pedestrian improvements, though determining the fee for each ATG will surely be a difficult debate, one that will hopefully not occur in a back room somewhere.
In December 2008, the MTA released a request for proposals  (RFP) for a nexus study (PDF ) to determine the specifics of the mitigation fees; the deadline for selecting a consultant is February 6th and the study is expected to be completed in one year.
The San Francisco Bicycle Coalition (SFBC) is not happy to wait that long and thinks the solution is much simpler (PDF ), that San Francisco can walk away from considering LOS as an environmental impact under CEQA. CEQA directs local agencies to set objectives, criteria, and procedures for determining environmental significance at the local level and there is already disparity in how cities in the Bay Area treat LOS.
San Jose, for example, has determined that LOS will fail in a large swath of their downtown development area but that the value of adding dense housing and commercial space near transit trumps the inconvenience to motorists of waiting in traffic.
Likewise, the SFBC points to a precedent for a departure from the CEQA administrative guidelines that occurred in 2002. In the Transportation and Traffic section, the guidelines ask “Would the project result in inadequate parking capacity?” and the assumption is that if so it would be a significant environmental impact and need to be mitigated. But in the “Emporium” case (San Franciscans Upholding the Downtown Plan v. City and County of SF ) a judge ruled that:
Parking shortfalls relative to demand are not considered significant environmental impacts in the urban context of San Francisco. Parking deficits are an inconvenience to drivers, but not a significant physical impact on the environment.
The SFBC argues that intersection backup should be considered a social inconvenience and not an environmental threshold of significance. It concedes that the secondary effect of congestion at intersections, like pollution, can be analyzed with air quality analysis under CEQA and that LOS is redundant for this purpose. Given that San Francisco doesn’t suffer from carbon monoxide hotspots and adverse pollution due to improved vehicle technology and a good deal of wind, the true environmental impact of traffic will be rare.
Flickr photo: Thomas Hawk