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Open Thread: Big Dig Alternative Analysis Released

How did your favorite alternative score? Click on the image to see a legible version.

You have to hand it to the public outreach folks for the I-710 Big Dig Project. Nothing says "community involvement" quite like dropping an Alternatives Analysis that was completed in December of last year to the public at Friday, at 3:50 p.m. before a holiday weekend.

Still an abject refusal on Caltrans part to accept that connecting two highways might somehow result in increased air pollution.

The analysis narrows down the alternatives that will be studied in the Environmental Impact Report to five potential projects. Yes, one of them includes digging a really big tunnel. However, the document recommends "refining" each of the alternatives to better fulfill the projects overall goals. For example, the tunnel option also should include a look at Bus Rapid Transit. The Bus Rapid Transit option should include other Transportation Demand Management evaluation and so forth.

We wanted to create a place for interested parties to discuss the Alternatives Analysis over the weekend, especially since Monday is a holiday. After the jump is the five project descriptions that live to be studied another day, a description and the recommended refinements. All information is directly from the executive summary.

No Build

The No Build Alternative includes all of the projects that are identified in the financially constrained project list of SCAG’s 2008 Regional Transportation Plan (RTP): Making the Connections. The No Build Alternative also includes currently planned projects in Los Angeles County that are identified in Measure R, as well as those in the “Constrained Plan” of Metro’s 2009 Long Range Transportation Plan (through the year 2035). The No Build Alternative does not include any project in the SR 710 corridor in the study area

The No Build Alternative should be updated to reflect the financially constrained project list in the 2012 Regional Transportation Plan/Sustainable Communities Strategy (RTP/SCS). This plan was adopted by SCAG after the initiation of the AA, but it would be appropriate to update the No Build Alternative in the PA/ED phase to be consistent with the newly adopted plan. The ridership and travel demand forecasting in the PA/ED phase will be based on the 2012 RTP/SCS.

Transportation System Management/Transportation Demand Management

The TSM/TDM Alternative consists of strategies and improvements to increase efficiency and capacity for all modes in the transportation system with lower capital cost investments and/or lower potential impacts such as substantially increased bus service in the study area, active transportation (pedestrian and bicycle) facilities, intersection spot improvements, local street improvements, and Intelligent Transportation Systems (ITS) elements. The transit service improvements included in the TSM/TDM Alternative are illustrated in Figure ES-3. These transit improvements are also included in the BRT and LRT alternatives, but are not included in the freeway and highway alternatives.

The TSM/TDM Alternative was found to have potential right-of-way impacts, primarily resulting from the spot intersection and roadway segment improvements included in the alternative. These spot improvements should be refined in coordination with the local jurisdictions to maximize the alternative’s benefits and to minimize its impacts. In addition, these improvements should be refined to identify opportunities to create “complete streets” that enhance the pedestrian and bicycle environment and to ensure that they do not detract from it. The other components of the TSM/TDM Alternative should also be reviewed and refined to look for additional opportunities to improve the performance of the alternative.


Alternative BRT-6 would provide BRT service between Whittier Boulevard, just south of the Gold Line Atlantic Station, and Pasadena City College (PCC) and the California Institute of Technology (Caltech) in Pasadena.

Alternative BRT-6, like all of the BRT alternatives, would displace a large amount of on-street parking. Therefore, refinements should be considered to its design, alignment, and/or operational characteristics to minimize their impact to on-street parking. Refinements should also be considered to maximize ridership and productivity (passengers per bus).


Alternative LRT-4A would begin at an aerial station on Mednik Avenue adjacent to the existing East LA Civic Center Station on the Metro Gold Line. It would remain elevated as it travels north to a station adjacent to Cal State LA, then descend into a tunnel north of Valley Boulevard and end at an underground station beneath the existing Fillmore Station on the Metro Gold Line.

Alternative LRT-4B was developed as a design variation of Alternative LRT-4A to reduce the length of tunneling required. Alternative LRT-4B would follow the same path as Alternative LRT-4A to the Cal State LA Station. Instead of immediately entering a tunnel, Alternative LRT-4B would continue on an elevated structure above Mission Road, turning north on Palm Avenue where it would descend to grade on Palm Avenue. Alternative LRT-4B would then enter a bored tunnel before Main Street and continue along an alignment similar to that of Alternative LRT-4A

Alternative LRT-4A/B station locations should be refined to maximize ridership, minimize property impacts, and to facilitate transfers to the Metro Gold line at its northern and southern termini.

Alternative LRT-4A/B could be combined with enhanced bus service, including feeder routes to its stations. By making Alternative LRT-4A/B the spine of a transit network that serves destinations to its east and west, and not solely along its alignment, it may be possible to attract additional transit ridership and improve the performance of this alternative.


Alternative F-7 would also originate at the existing SR 710 stub north of I-10. It would connect via a bored tunnel to the existing SR 710 stub south of the I-210/SR 134 interchanges in Pasadena. This alternative would also be an eight-lane freeway with two bored tunnels for directional travel similar to Alternative F-2.

Alternative F-7 should incorporate refinements to its design and alignment to minimize its impact. Potential tolled  operations to improve its financial feasibility should also be evaluated. Restriction on use by trucks should be  evaluated to determine if they are effective at reducing impacts.

Alternative F-7 could be combined with a BRT or other enhanced bus service to improve the performance of this alternative on the performance measures related to the transit system. Alternative F-7 was found to not increase transit ridership or transit mode share. By introducing a well-designed BRT or other enhanced bus service into Alternative F-7, it may be possible to diminish north-south transit travel times through the study area and attract
additional transit ridership.

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