Green Bridge design decided

07/11/2018

Caltrans has unveiled its final design plans to tear down and replace the Green Bridge to ensure that the critical gateway to Point Reyes Station can withstand an earthquake. It’s a project the agency says will cost $8 million and take a year to complete, including a complete closure for up to three weeks.

The agency’s final environmental impact report, released last week, addressed the persistent call from community members to reconsider retrofitting the bridge, but maintained that a replacement is necessary.

Caltrans first discounted the retrofit in its draft of the environmental impact report, released last summer, citing a three-year timeframe and greater environmental impacts and arguing that it would be a less safe structure. 

Because a retrofit was not an evaluated alternative in the draft, Caltrans could not go that route without re-writing an entirely new environmental report. To appease residents, the agency has since issued a variety of supplemental documents that justify why structural engineers decided a retrofit would be inadequate.  

Of the five design alternatives and a no-build option Caltrans did consider, the agency has selected a three-span, concrete bridge design with the shorter of two proposed timelines as its preferred alternative.

Including five-foot-wide shoulders, the bridge will have a roadway that’s 32 feet—six feet wider than the existing structure—as well as one six-foot sidewalk. The bridge does not have a truss, or the metal frame that’s currently painted green, and therefore will not be as tall.

As the narrowest of the designs, it will have the “least distraction of views toward the creek and of Point Reyes Station” and will “not detract from community character,” the report states.

To construct the bridge, Caltrans will assemble new structural elements at nearby staging areas, possibly resulting in one-lane closures and traffic slow-downs. During a three-week period scheduled for September 2021, the bridge will close while construction crews work around the clock to remove the existing bridge and install the new one.

Traffic will be detoured south-to-north through Olema, along Platform Bridge Road and Point Reyes-Petaluma Road—a nine-mile route. The alternative timeline for some of the other designs was three years, with no closures.

In the final E.I.R., Caltrans stated that its chosen design was among the least environmentally impactful in terms of ground disturbance and property impacts during construction. The alternative also minimizes the duration and extent of impacts to the aquatic habitat in Lagunitas Creek and requires one of the smaller temporary construction easements on private property, including for the Point Reyes Animal Hospital—whose owners have stated that the construction threatens to put them out of business. 

The estimated cost, at $8 million, is the cheapest of the build alternatives, which ranged up to $12.6 million.

The final E.I.R. includes a host of avoidance, minimization and mitigation efforts, such as containing in-water work from the stream, putting up fencing around the most sensitive areas, erecting temporary barriers to reduce noise and dust pollution, re-seeding native plants, replacing trees and restoring wetlands.

Construction is slated to begin in the spring of 2021, pending permits from federal and state agencies. 

But the community has other ideas.

Inverness resident Bob Johnston, who is leading a group of around 20 community members called Friends of the Green Bridge, said this week that they plan to follow through on their intention to sue Caltrans.

Currently in search of legal representation, Mr. Johnston said their main argument is that the agency violated the California Environmental Quality Act by not considering a full range of alternatives—and in particular a retrofit. 

A retrofit was addressed in the draft environmental impact report, but was evaluated in a section discussing build alternatives that “were considered but dismissed.” Because it was not included as an alternative, legally the agency could not consider it in the final document without first rewriting the draft. 

Mr. Johnston, a former University of California, Davis, professor who specialized in CEQA, also questioned Caltrans’s technical analysis behind its discounting of a retrofit, calling it “phony.”

Per CEQA rules, there are 30 days from the release of the final environmental document to sue.

Caltrans first introduced the project in 2015, after engineers determined that the 90-year-old structure does not meet current standards for earthquake resistance. At that time, many locals immediately clamored for a retrofit rather than a replacement, largely concerned about the strain that a long construction project would put on the town.

Despite some additions from Caltrans, such as a shorter timeline option, many residents have continued to fight tooth and nail against the proposed rebuild since the draft E.I.R. formally discounted a retrofit last summer. The majority of commenters opposed the project during a comment period on that document at that time.

Last December, the Point Reyes Station Village Association sent a letter to Caltrans that demanded to know how the agency planned to incorporate the feedback. The letter cited the agency’s lack of communication and requested an update on the planning process.

“In the light of [the] overwhelming opposition to Caltrans’ proposal, we are very concerned about Caltrans’ silence,” the letter stated. “We fear that one of these days Caltrans will simply issue a final decision without any further dialogue with the community and without any advance notice, and that such decision will be to implement the D.E.I.R. proposal (or one of the other tear-down-and-replace options) despite the community’s opposition to it.”

Though Caltrans did finally respond to the association’s letter in May after Assemblyman Marc Levine intervened, the agency continued to advocate for a replacement.

 

Why a retrofit was discounted

David Moser, a San Francisco attorney who co-owns property adjacent to the Green Bridge, has been particularly active in the quest to resurrect the retrofit option. In March, Mr. Moser filed a Public Records Act request with Caltrans for documents related to the project since the comment period ended last June. The agency has provided some documents, and has said it will complete his request this month.

Out of the documents he has received, Mr. Moser pointed to one email he uncovered from last July from the former Caltrans supervising bridge engineer for District Four, Kelly Holden, who left the post soon after. 

In the email, Ms. Holden questioned the technical basis on which the retrofit was discounted and excluded from the draft E.I.R. She said that her impression was that it was not necessary to retrofit the superstructure—the part of the bridge visible while driving—but rather just the substructure—everything below. 

“I did not realize that because only [a] substructure retrofit was needed, the original assumptions that caused us to toss the retrofit alternative were no longer valid,” she wrote to her colleagues. “And now we need to add the retrofit back into the mix of viable alternatives.”

Mr. Moser characterized this email as a “smoking gun.”

Yet subsequent emails in the same thread reveal that, despite some wavering, Ms. Holden’s colleagues re-affirmed the need for a retrofit of both the substructure and superstructure of the bridge based on information from the structure design team, justifying their decision that the necessary retrofit was not a viable alternative. 

Wajahat Nyaz, the Caltrans project manager, also told the Light this week that Ms. Holden had been mistaken. 

Perhaps in response to prodding from Mr. Moser and others, Caltrans released a memorandum late last month, mere days before it released its final E.I.R., that further walks through each of the agency’s steps in its process of evaluating and discounting a retrofit.

Mr. Moser remains unconvinced. “I think the memo is indicative of the fact that they recognize that they did not handle this retrofit question appropriately,” he said. “We’ve been asking for them to analyze a retrofit since the beginning—and they have refused. That’s a real, fundamental legal problem for them, and no amount of after-the-fact justification in a new memo is going to cure that.”

The memo, released on June 26, rehashes the general reasons why a retrofit was not one of the alternatives Caltrans fleshed out as project possibilities in its draft E.I.R.

According to Caltrans policy, retrofit alternatives are only considered when the current structure has deficiencies that can be addressed without a full replacement. In a 2016 investigation of corrosion on the bridge, Caltrans cited problems with the piers, piles and abutments as well as severe corrosion on the steel truss. “Virtually each major structural element of the bridge would require reinforcement, replacement, or refurbishing,” the investigation report states.

The June memo elaborates that there is no redundancy in the Green Bridge, unlike in modern-day bridges, meaning that members are interdependent and the failure of or damage to any one of the structural components could cause the entire structure to fail.

The memo, addressing the confusion that arose in Ms. Holden’s email, says that Caltrans structural engineers determined that both the superstructure and substructure require a retrofit based on a group of investigations, maintenance assessments and a seismic design recommendation from 2016.  

“Caltrans structural engineers in the division of engineering services determined that the effort required for a retrofit of the Lagunitas Creek Bridge to meet the Caltrans “no collapse” criteria would entail a substantially larger effort than the build alternatives… the effort was determined not to be a prudent use of resources,” the memorandum states.

The final E.I.R. also explains that, in addition to the prolonged time required to replace the corroded components, a retrofit is complex and would require a substantial temporary support structure as well as a detour bridge, resulting in greater environmental impacts than the selected build option.

A construction timeline of three years, comparable with the initial timeline Caltrans proposed for a replacement, was outlined for a retrofit.

“Finally, in addition to the primary seismic concerns, the retrofit would not meet the safety elements that the replacement alternatives would,” the final E.I.R. adds. 

According to Caltrans, a retrofitted bridge would need to be outfitted with a safety barrier to protect non-redundant parts from collapse in the event of a vehicle collision. This barrier would reduce the roadway by three to four feet and remove the two-foot shoulders, failing to meet standards of safe non-motorized accessibility.

 

Responses to comments

As is protocol, the final E.I.R. addresses the comments delivered during the public scoping period last summer.

Nine local businesses submitted comments, four of which advocated for a retrofit and five of which supported nixing the project altogether—including the owners of the animal hospital, who generated a high degree of community support in the last year. 

In the preferred alternative, temporary construction will take place at all four corners of the bridge, including south of B Street, a parcel with two residences on the southeast corner, the animal hospital property, and the parcel containing Captain Oko and residences on the southwest corner of the bridge.

Temporary staging areas have been identified to allow for equipment storage, equipment maintenance, and construction material storage during construction.

At the animal hospital, Caltrans will work in front of and within a strip of the parking lot, in part to temporarily relocate a power pole. Six undesignated parking spaces will be lost during construction, leaving four for the animal hospital, two for a rental unit on the site and eight additional spaces.

This outlines much less square footage than was determined in previous maps.

“What it really boils to for me is not the square footage—it is the ability for me to maintain my small animal hospital while there is constant loud noise and traffic delays,” Mary Whitney, who owns the hospital, said. “I can’t survive even a 20 percent reduction in income and this is going to be a huge impact given that people are really going to want to avoid that intersection. Additionally, this is supposed to be a healing environment for animals. Animals hate loud noises.”

Like Mr. Moser, Ms. Whitney cannot join the impending lawsuit from Friends of the Green Bridge because she owns property in the construction zone. Still, she hopes the group prevails. Otherwise, she said, she plans to hire her own eminent domain lawyer.

The final E.I.R. answers concerns about the hospital by pointing to strategies to reduce dust and noise, and claims compliance with the Uniform Relocation and Real Property Acquisition Act. The project description eliminates hammer-pile driving, the noisiest method of installing piles for the piers. For structures within 50 feet of the project, construction methods and equipment will also be adjusted to avoid vibration-related damage.

In response to commenters asking about a no-build scenario, Caltrans painted a portrait. In the case of bridge failure during an earthquake—the agency notes that the San Andreas Fault is 0.4 miles away—Caltrans would have to conduct an emergency replacement, which would be expedited and exempt from CEQA, since it would be necessary to maintain service essential to public health. Nevertheless, the throughway would likely be closed for eight months while the agency worked around the clock at the site, Caltrans estimated.

The agency illustrated the impacts of such a long closure, such as on tourism and the local economy. Use of the bridge, an essential artery for West Marin, is high: Caltrans said peak weekday traffic on the bridge is around 700 vehicles every hour, with up to 1,300 on weekends.

Emergency services from the Point Reyes fire station would also be substantially delayed by the nine-mile detour, with impacts felt throughout West Marin.

And while community members have argued that an earthquake is unlikely, Caltrans pointed to statistics that show a high risk. Data from a 2015 Uniform California Earthquake Rupture Forecast that says there is a 72 percent chance of a magnitude 6.7 or larger earthquake within the next 30 years in the San Francisco region. “The argument that seismic hazard at the project site is grossly overestimated is not supported by good science,” it states. 

Caltrans said it has prioritized replacing the Green Bridge based on its relative vulnerability in the case of seismic events and will fund the project through the bridge component of California’s highway operations and protections program.

In the comments section of the final environmental report, Caltrans again addresses the rejection of a retrofit. The idea that a retrofit will be “less intrusive,” it argues, is wishful thinking. In terms of duration of construction and physical impacts—including to nearby properties and biological resources—impacts would be greater, the agency states, for all the retrofit alternatives studied. These include designs submitted by a local structural engineer, Alistair Lizaranzu, who went through the trouble of coming up with his own alternatives.  

 

The final environmental impact report, including the agency’s responses to public comments, can be reviewed on Caltrans website, under “Lagunitas Creek Bridge Project.”