Power has been restored to about 5% of customers in Puerto Rico after nearly all of the island’s 1.57 million customers were left in the dark on Sept. 20, when Hurricane Maria left the power grid in shambles.

An initial reconnaissance of the damage from the Sept. 19 Puebla-Morelos earthquake that killed over 300 people and toppled over 40 buildings in Mexico City found that seismic building codes—put in place after a 1985 deadly quake—were effective, according to a Stanford University professor.