At a recent MBTA board meeting, it became alarmingly clear that the MBTA is behind in its planning for climate resiliency. Add that challenge to the challenges of catching up on maintenance, assuring safety, and expanding service.
Andrew Brennan, Senior Director for Energy and Environment, explained to the board that the MBTA completed a “high-level” vulnerability assessment of the system in 2017. His presentation materials are here and his talk begins at 2:55 in this livestream of the June 10 board meeting.
The 2017 high level assessment revealed the obvious: Namely, that the most exposed asset is the Blue Line and that the greatest risk to the Blue line comes from flooding due to sea level rise. Only months after the assessment, the winter high tide of 2018 flooded Aquarium station.
As to the lowest lying assets on the Blue line (Aquarium station and the Orient Heights Maintenance Facility), more detailed engineering studies have been completed to identify just how they would be flooded and what can be done to protect them: for example, raising openings like vent shafts and raising the most water sensitive components like transformers.
Yet, the full costs of even those targeted improvements are still not fully known. Brennan further stated, “Most stations on the Blue Line could be exposed to flooding by 2070.” He acknowledged that there is no assessment of the total cost of protecting the Blue Line.
As to the Green Line, one vulnerability is already known. The MBTA incurred tens of millions of dollars of loss due to subway flooding at Kenmore station in the heavy rain of 1996. More than 20 years later a project is finally underway to build a door to close the tunnel opening next to the Muddy River.
All of the subway lines run through areas that will become increasingly vulnerable to flooding. The major transit nodes at North and South Stations sit next to the harbor. Careful projections by the City of Cambridge put the Alewife area at high risk of Mystic River flooding by 2070.
Vulnerability assessments of the Red Line and the Green Line are to be completed in calendar 2020. Unfortunately, all it takes is one vent grate at a low spot to channel a heavy flow of corrosive saltwater onto the tracks, signals, and power systems that taxpayers are working so hard to upgrade. The presentation was ambiguous, but it appears that a rigorous analysis of specific exposures for the lower lying Red and Green line locations is years away.
The board members were politely exasperated by the presentation. Their reaction was to seek to engage more closely with other regional authorities in planning for more comprehensive solutions. Board Chair Aiello said, “I don’t think the authority should be spending money caulking things up . . . when it’s part of a broader thing.” Board Member Lang said, “I’m sitting here feeling like we are putting a finger in a dike. . . . It’s a losing game unless there is a much more coordinated approach that looks at all of this stuff and it’s just not happening. . . . I was ready to shoot myself listening to your presentation.”
Reviewing the meeting, I welcomed the Board’s intention to help push for regional solutions. Yet, my own considered view is that there is no long-term regional solution to the sea-level rise problem for Boston. Until we achieve global control of carbon emissions, the risk of flooding of our most vulnerable assets will continue to rise. The floods will eventually happen. If we have not made the vent-shaft-by-vent-shaft fixes to contain the damage, the region will be crippled. Our adaptation goal for the MBTA should be to assure that our current surge of investment will have a hundred year life even in a worst case, “business as usual” global carbon scenario.
For me, the meeting moved MBTA climate resiliency from my watch-the-agency-and-worry list to my legislature-needs-to-act list. I favor an approach to investment in climate adaptation that is informed by clear thinking about which assets are both vulnerable and critical. The MBTA is certainly one of those assets.
Photo credit to the MBTA — photo included in Brennan presentation.