Tens of thousands of people across Puerto Rico woke up Friday without running water as authorities began a mandatory rationing program in response to a severe drought that has pushed the island's main reservoirs to critically low levels, compounding years of strain on aging water infrastructure. Puerto Rico Gov. July was the driest month on record for San Juan in more than 120 years and the second-hottest ever recorded for the capital, according to drought monitoring data. Roughly a quarter of Puerto Rico is currently experiencing severe drought conditions, with another 36% under moderate drought, according to the U.S. Drought Monitor. Puerto Rico's water crisis predates the current drought.