A Bay Area Regional Agency Primer: Chapter One, The Metropolitan Transportation Commission

The Metropolitan Transportation Commission (MTC) is one of four regional agencies that monitors, forecasts, and affects planning for all counties in the Bay Area. These agencies include the Association of Bay Area Governments (ABAG), the Bay Area Air Quality Management District (BAAQMD), and the San Francisco Bay Conservation and Development Commission (SFBCDC).

To better understand travel patterns throughout the Bay Area, MTC created “superdistricts.” Each county was assigned their superdistricts by grouping areas together that share common characteristics and geographical boundaries. This makes it easier for MTC to study each county’s travel patterns.

While the Bay Area has a total of 34 superdistricts, Marin County is comprised of three superdistricts. If you look at the attached, updated PDF of the 2012 map of adapted Marin County Superdistricts, you can see that Marin is divided up into three land areas that broadly represent Southern Marin, Central and West Marin and Northern Marin.

Each superdistrict can be used to estimate the number of work trips made each year to this area.  Workers in each superdistrict are called “commuters”. Typically commuters drive to work but some may take public transit, walk, and or bike.

In Marin County, commuters can come from anywhere. For example, a commuter who lives in Novato might drive to Southern Marin to work and vice versa.  Workers who live outside of Marin in any of the other Bay Area regions and who drive to Marin for work are called “in-commuters.” In-commuters are a subset of commuters. San Francisco has the most commuters of any city in the Bay Area. St. Helena/Calistoga has the fewest commuters.

Each of Marin’s superdistricts are numbered and identified as follows: #34 is “Mill Valley/Sausalito”(Southern Marin); #33 is “San Rafael”(Central and West Marin); #32 is Novato (Northern Marin). Our county has the highest number of “commuters” in San Rafael, followed by Mill Valley/Sausalito, and then Novato.

The most recent MTC data from 2008, (see page 75 of the PDF of the "Travel Forecast Data Summary: Transportation 2035 Plan For San Francisco Bay Area") using a 2006 base, it shows San Rafael with 84,507 commuters, Southern Marin with 70,901 commuters, and Novato with 44,720 commuters. San Rafael’s commute work trips per year are almost double those of Novato’s and Southern Marin’s are 59% higher than Novato’s. 

The data from the Census Job Count from 2010 shows the same ratio of Novato compared to the other two Marin superdistricts as in 2006. (Add the inflow/outflow All Jobs Count for workers employed in selection area for each city in each superdistrict). However, the Census numbers are almost 50% less than MTC’s numbers of 2006. How do we explain this significant difference in four years? The 2010 data is more current and housing, job and transit planning should reflect more recent data.

This information is used by all the regional agencies to determine how to make improvements and additions to planning for public transportation and housing in order to reduce the number of people commuting in the Bay Area. The goal of reducing work related traffic is to reduce Green House Gas emissions (GHG's). Legislation that mandates this reduction began with two bills: AB32 and SB375.

According to MTC’s 2035 Equity Analysis Report (page number 40), looking at pollutant type and by county and community of concern, the communities with the highest emissions densities are downtown and eastern San Francisco and Marin County. In order to help Live Local Marin (a coalition of non-profits) realize their goal of live closer to where you work and drive less, and to help reduce traffic and greenhouse emissions on highway 101 it would make the most sense to distribute affordable housing across all Marin districts proportionately where the highest concentration of jobs are.

As of 2013, the city of Novato has added a significant portion of the affordable housing available in Marin County to its geographical area.  Novato must not be made responsible for accommodating all or most of Marin’s affordable housing. This would defeat the goal to reduce traffic and emissions on highway 101 since Central and Southern Marin have the highest number of commuters, not Novato. We must ask ourselves why Novato has become the target of so many advocacy groups when it comes to the construction of new affordable housing in Marin.