Published November 15th, 2017
Lafayette's proactive measures prevent road collapse
By Pippa Fisher
Mike Moran looks down at the 40-foot slide area. Left: the new drainage pipe sits behind newly planted trees along the creek bed. Photo Andy Scheck
In a race to beat the winter rains, the recent major road stabilization project on St. Mary's Road in Lafayette was completed in the nick of time, just one day before the first significant rain of the season. Funded by the Federal Emergency Management Agency and completed 11 days ahead of schedule, this comes as a relief to the Lafayette Public Works Department.

In early January amid all the heavy rain, the shoulder of the road slid about 40 feet down to the Las Trampas Creek, taking with it a tree and laying vulnerable a high pressure gas line. Public Works Director Mike Moran says the work was a permanent stabilization project and should prevent a recurrence.

"If it were left undone St. Mary's Road at that location would have collapsed. Maybe within this winter but certainly sometime in the near future." Moran added that if the road had collapsed it would have impacted not only the gas main but also a sewer main and a water main. "The gas is located near the failed shoulder of the road and that was my biggest immediate concern."

"We needed to prevent any additional erosion or we could lose that section of St. Mary's Road into the creek (we were able to do that by covering the slide with plastic sheeting). Almost simultaneously, my thoughts went to how can we fix this and how fast can we get it done," said Moran, explaining how shocked he was when he first saw the slide.

Valentine Corporation of San Rafael was awarded a contract in the amount of $493,369 at a city council meeting in August. "We are fortunate that this slide occurred during a declared disaster because this made our repair eligible for federal funding," Moran said.

"For our job, FEMA has said they will reimburse 75 percent of qualifying expenses," Moran explained. "They will only pay to restore to previous condition, no betterment. Additionally, the California Emergency Management Agency will also reimburse 75 percent of the remaining 25 percent, or 18.75 percent. So theoretically the city can complete this project and be reimbursed for 93.75 percent of the costs."

Moran credits the contractors saying they did a great job and brought in the right equipment to reach down the steep slope to the creek, using a Gradall loader with a 60-foot reach from the roadway at the top.

Although drivers might experience frustration while held up in traffic, there are perhaps many aspects to a public works project that residents do not consider. Moran refers to the flaggers who were controlling traffic. "I did receive a request to use a timed temporary signal but denied that request for a couple of reasons. One reason is that two flaggers can adjust the amount of time they let through northbound or southbound traffic based on actual traffic loads. Humans will be more efficient than a timed signal."

"Another reason is that we still had to hold traffic in both directions when equipment was blocking both lanes and they would still need a traffic controller to operate the signal so that it would show a red light in both directions when both lanes were blocked."

Moran points out, "Because this repair is on a creek bank, the city needed to work with Fish and Wildlife, the U.S. Army Corps of Engineers, and the Regional Water Quality Control Board. This is quite a process and took months to get all required permissions. We will also have to monitor and report on the planting and riparian restoration for five years following the completion of the project."

With water from the rains now starting to flow in the creek, Lafayette is ahead of the game on St. Mary's Road.

St. Mary's Road at the point of slide - exposed pipe visible. Photo provided

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