Supply Chain Resilience : Push and Pull in Catastrophes
demic , it will be much more difficult for consumers to express their demand . The ability of the supply chain to hear the pull signal is likely to be seriously complicated or entirely cut-off .
Grocery demand is expressed primarily through some sort of digital transaction at the point of sale . In recent years , roughly three-quarters of U . S . grocery purchases have been made with some sort of card . In April 2020 , about forty-five percent of grocery shoppers used a credit card and thirty-nine percent utilized a debit card . 38 Over eight percent of U . S . grocery purchases are made with an Electronic Benefits Transfer ( EBT ) card connected to the Supplemental Nutrition Assistance Program ( SNAP ). 39 These systems have adapted effectively to pandemic-related shifts . 40
The flow of groceries in the aftermath of Cascadia will be as or more important as it has been during the pandemic . If the network cannot receive pull signals , the network does not know where to push supply . With grocery distribution centers damaged or worse , bridges gone , and roadways seriously disrupted , push will be much more difficult post-Cascadia than during the pandemic .
Digital transactions are typically routed over public telecommunications networks . Both electric power and telecommunications connections are needed to successfully complete financial transactions . Landline , cellular , and WiFi are the most common modes of connection . According to projections , “ In a great Cascadia earthquake , millions of customers could lose service as a result of broken cables and equipment failures at telecommunications centers . The earthquake may damage cell towers , throw antennae out of alignment , and break fiber connecting cables , thereby disrupting service to many cellular customers as well . It is likely that the earthquake will sever major undersea transpacific cables , disrupting service not only to East Asia , but also cutting Alaska off from the rest of the United States . It could take two to three months to restore these important
41 , 42 connections .”
Two- or three-days dark is probably recoverable . But if digital transactions for groceries are not possible for two or three months , the implications are dire for the 4 million-plus people of Puget Sound .
42 Walmart ’ s Point-Of-Sale transaction system utilizes a private satellite network . In case of a seismic event , digital transactions should continue to be made and pull supply if the facility survives and has a source of electric power .
31