VANDENBERG AIR FORCE BASE, Calif. -- With the recent deluge of rain, a sinkhole appeared on Coast road, five weeks ago, partially collapsing one lane.
The damaged road is the only safe way to get to Space Launch Complex-6, and as such became a priority to repair, in order to prevent mission delays.
“The root cause of the sinkhole next to Coast road is a deteriorated seven foot wide culvert that is 60 feet below the road surface,” said Lt. Col. Ryan Novotny, 30th Civil Engineer Squadron commander. “Significant rain totals this winter worsened the damaged culvert, causing the surrounding soil to be washed away and causing the sinkhole above. The real challenge with this, is that the depth and size of the culvert make it a complicated repair.”
Working with a short timeframe, leadership decided the best method for fixing the damaged culvert would be to create a bypass road around the damaged area.
“The culvert collapse was ultimately caused by corrosion, which occurs all over base,” said Lt. Col. Alex Mignery, 30th CES operations flight commander. “We have the third most corrosive atmosphere in the entire DOD. This road will be instrumental in actually fixing the collapsed culvert and will be a major effort to repair when we do start on the culvert itself.”
The culvert under the bypass road is constructed of concrete, but it was the metal culvert on the other side of the road which failed, causing the sinkhole.
“The 30th CES has evaluated the situation and taken all precautionary measures to stabilize the area,” said Novotny. “The road remains safe to travel across, but we are building a bypass road to allow operations to continue while a permanent repair is completed, which will involve a contractor closing the existing Coast road near the culvert.”
In order to move the road away from the sinkhole and the collapsed culvert, an old railroad track that was no longer in use had to be dismantled to make way for the bypass, all within a short amount of time.
“This whole process has been accelerated,” said Mignery. “We have already had an engineering firm come down and do a complete design for the bypass road. And now we have the construction contract awarded and mobilized, with an estimated completion date of March 27.”
Teamwork and constant communication were essential in starting the process to prevent any mission delays from SLC-6.
“Without the timely decision-making of National Reconnaissance Organization, United Launch Alliance, 30th CES, and the Corps of Engineers leadership as a corporate effort, focusing on the final solution among possible courses of action would not have been achieved,” said Stan Chang, 30th CES engineering flight chief. “Communication was key, up-and-down and side-to-side. Besides continuous emails addressing and resolving all aspects of the concern, at least two tag-up meetings a week were held to assess status and determine direction as design was reviewed and integrated with construction planning.”