Sinkholes, Eroding Interstate Foundations, and Rainfall--Oh, My!
Updated: Mar 27
Remember the extreme weather in January in the San Francisco Bay area and how we talked about erosion and how the weather would affect roadways? If you do, you remember how we looked at how extreme rain and flooding will wear down the ground underneath asphalt, causing the roads to be more susceptible to cracks and breaks, creating exponential damage as more water enters the foundation.
The results of these storms showed up in damage along I-580 and I-78 in California, thanks to sinkholes and collapsed retaining walls. The bomb cyclone from this year’s January had the SF bay area underwater for weeks. Even with better maintenance, drainage, and planning, roads are not made to be underwater for extended periods of time. I mentioned that we’d see how this standing water affects the roadways, and this week, a retaining wall along I-580 backed up traffic for days when it collapsed due to erosion. The issue now is that without the retaining wall, the ground underneath continues to shift and weaken as current rainfall contributes to the already damaged interstate.
The Livermore road repairs are expected to take much more time than temporary safety barriers, and plastic tarps can make up for them, especially with increases in rainfall even still. As traffic shifts over 1-2 lanes for road closures, the weight of hundreds of commuters across an already eroding interstate only furthers damage. Structural engineers must carefully calculate the cost of repairs and rebuilding. As of March 20th, there were 30 crews estimated to be working on repairing not just the fallen barrier but also cracks and potholes that have since appeared. However, as the ground is already saturated, much more extensive work will need to be put into rebuilding the entire interstate.
State Route 78 is still in construction repairing a major sinkhole, so far taking over a week to repair, thanks to more damage appearing in the area. Currently, surrounding neighborhoods are experiencing five more sinkholes and intense damage from road erosion caused by excess rainfall. One area claims that below the asphalt was “unstable, oversaturated clay.”Temporary repairs can only be made when the rain stops, but again, these quick repairs will not be enough for the entire re-do that needs to be done.
This is just a warning sign for what's to come for other states that haven’t overhauled their interstate systems in decades, patching the same roadways made in the 70s and expecting them to continue to hold. With infrastructure bill funds being doled out this year, now is the time to finalize your projects, get funded, and get started. Keep us in mind when it comes time to put up your signs!