More Cars = Less Congestion? Supes Grill CPMC’s Perplexing Traffic Analysis

Image: ## CPMC##

How can more cars relieve congestion at an intersection?

Members of the Board of Supervisors pursued that question this week during two hearings on California Pacific Medical Center’s plan to build the massive new Cathedral Hill medical center at Geary Boulevard and Van Ness Avenue. The board postponed a vote on Tuesday to approve the project’s environmental impact report, which was approved by the Planning Commission in April despite the 1,200 parking spaces it would include.

The thousands of car trips those parking spaces would induce have troubled residents and livable streets advocates. Scrutinizing the traffic impacts predicted in the EIR, supervisors grilled Planning Department staff over the perplexing finding that congestion at two intersections would actually be reduced, despite additional vehicle traffic.

Viktoriya Wise of the Planning Department made numerous attempts to explain the perplexing “peak-hour factor” used in Level of Service, the automobile-centric traffic formula which planners must use to analyze traffic impacts. But Supervisor David Chiu wasn’t satisfied, asserting that the peak-hour factor wasn’t used in other cities, according to experts he’d spoken to.

However, supervisors stopped pressing the question after an explanation from Greg Riessen, also of the Planning Department. “This is such an arcane little element of traffic engineering, that, in my six-year career, has never got anywhere near this much attention, so it’s very exciting to be here and explain this to you,” said Riessen, eliciting chuckles from the board and the public. Assuring members that the often counter-intuitive formula is used around the country and on other projects in San Francisco, he explained (here’s an edited summary):

The peak hour factor is trying to quantify the peak 15 minutes of congestion within the peak hour. If you put more cars through the less-congested approaches at an intersection, the overall weighted average of delay could go down sometimes. Our standard practice is to increase the peak-hour factor to represent the spreading out of traffic as your fluctuations decrease over time, but sometimes that’ll result in results that don’t necessarily jive with your intuition. It’s kind of more a question of, why does Level of Service do that? And it’s frankly one of the reasons why we need to abolish Level of Service.

Clear enough? Seemingly satisfied with Riessen’s explanation, the supervisors moved on.

The project’s development agreement includes a fee on parking: $0.75 for every car during peak hours, and $0.50 during off-peak hours. That money would go to the SFMTA for local pedestrian and transit improvements, including the Van Ness and Geary BRT projects. CPMC will also pay the city $400,000 to study bicycle improvements on connecting corridors. The parking fee, however, is set to end after 10 years.

The EIR is set to return to the board for approval on July 31.

  • Richard Mlynarik

    Crazy object-du-jour to legally mandated construction of life safety critical hospital to meet seismic survivability standards = proxy pissing match of the California Nurses Association.

    This is all, 100%, about whether Cathedral Hill is required (independent of any vote by actual working nurses of the future facility) to be a union shop.

    That’s it.

    It’s embarrassing to see “transportation activists” entering into this disingenuous mud-flinging contest under either false or completely naive pretexts.

    If you want to carry water for the CNA, just come out and say it.

    It you want hospital construction (for the non-profit CPMC) to be dragged out years longer, and the costs of hospital construction to be padded out by extra hundreds of millions of dollars, well, keep right at it.  Somebody Else will pay for it, after all!  Somebody Else.

    This is the sort of Muni-level crap and lose-lose scamming one expects living in San Francisco, but God it hurts to see it still.

  • Joel

    This is one of those rare times where I find 100% truth in Richard’s rant.

    Certain supes are scraping the barrel to find a reason to oppose this project. CPMC is providing offset benefits that won’t be matched by other developers years down the line. If it means funding BRT sooner, I’m all for it.

  • Charles_Siegel

    The link to your 2009 article about LOS leads me to ask:

    What has happened to attempts to reform CEQA’s Level-Of-Service standard? I was very hopeful after reading the 2009 article, but nothing seems to have happened.  Can we have an article with an update on the issue?

    The initial series of articles said:
    “Accordingly, the OPR has until July 1st to complete its analysis of the CEQA changes, at which point it would go to the California Natural Resources Agency, which has until January 1, 2010 to enact the regulations.”
    Presumably, that state-level attempt at reform failed.

    The initial articles also said:
    “CEQA specifically delegates planning decisions to the local level.

    The adherence to LOS was a convention adopted by San Francisco and most
    other municipalities around the state to evaluate transportation impacts
    under CEQA.  … advocates spent years lobbying the Board of Supervisors to
    make changes to the rule, though with mixed results.  After the board
    finally called for a study of the impacts of LOS analysis, the San
    Francisco County Transportation Authority (TA) issued a significant
    report (PDF)
    at the end of 2003, which asserted that “existing LOS measures and
    standards ostensibly favor preserving auto level of service at the
    expense of improving transit, bicycle, and pedestrian conditions” and
    argued that new measures of analysis besides LOS should be developed.

    Within a couple years the Board of Supervisors and issued
    a resolution (PDF)
    stating that “automobile analysis alone is not an appropriate metric
    for assessing environmental impacts and for analyzing projects that may
    improve overall environmental quality in conformance with [the Transit
    First policy].”

    Shortly after the article appeared, I heard rumors that both San Francisco and San Jose were working on alternatives to the LOS standard that involved trip generation.  Instead of looking at a project’s impact on LOS and widening the street, the new standards would look at the number of auto trips and would charge a fee to be used for trip-reduction programs.

    But I haven’t heard since whether there has been any progress on these attempts.

  • Check out the later link, “abolish Level of Service”:

  • Charles_Siegel

     Aaron: Thanks.  I appreciate the link, and I will forward it to people who have said they are interested. 

    One tip that I have learned about computer writing: It is good for an article to have a heading with key words that help users find the article that they want when they are looking at a list of search results.  It would be easier to find this article using google if its title were

    SF Agencies Take Aim at Level of Service Standard
    rather than
    SF Agencies Take Aim at Bureaucratic Obstacles to a Transit-First City

    About a month ago, I spent a lot of time searching for recent articles about LOS reform, and I did not find this article.  It did not come high on the list of results of my search for “Level of Service.”

    I appreciate your coverage of the issue.

  • Sprague

    For a range of reasons, I hope that this hospital construction project will be approved as soon as possible.  However, from a transit-first perspective, I don’t understand why the parking fees will expire after ten years.  The impact of hundreds or thousands of additional daily auto trips to this location will not be going away in ten years time.  As always, thank you Streetsblog and Aaron for your coverage of yet another issue important to San Francisco and sound transportation policy.


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