Brendan Gibbons / Rivard Report
A year ago, water flowing up from the underground Edwards Aquifer still partially filled the spring-fed pools at San Pedro Springs Park north of downtown.
Now, the springs are completely dry, a sign of arid times returning to San Antonio. On Tuesday, water in the aquifer dropped to its lowest level since January 2015.
“We’re definitely seeing drought conditions expanding across Central Texas,” said Texas State Climatologist John Nielsen-Gammon, a Texas A&M University professor of atmospheric sciences.
After scant rain fell on San Antonio in the typically rainy months of May and June, parts of northern Bexar County are in moderate drought, according to the latest U.S. Drought Monitor maps published June 28. Central and southern Bexar County are still considered “abnormally dry.”
Another measure of how drought affects San Antonio is the level of the Edwards Aquifer, measured by a monitoring well at Fort Sam Houston called J-17.
The J-17 well’s level often serves as the yardstick local officials use to decide when to declare pumping restrictions on the Edwards, a vast underground rock layer that serves as the main water supply for the San Antonio region.
With the level now at 641 feet above sea level, the aquifer is in Stage 2, a 30 percent cutback on those who hold pumping permits.
That’s a marked change from this time last year, when the J-17 level sat more than 20 feet higher at 663 feet and cutbacks hadn’t kicked in yet.
Now, San Antonio, New Braunfels, Alamo Heights, Leon Valley, and Balcones Heights are among the cities under Stage 2 water restrictions, with irrigation use limited to certain morning and evening hours once per week.
These and other cities enacted their drought restrictions to comply with pumping cutbacks during droughts enforced by the Edwards Aquifer Authority. The cutbacks are meant to preserve enough water for all the aquifer’s users and for endangered species that depend on flow from aquifer-fed springs.
Next week, the San Antonio Water System will go from storing Edwards water in its underground water bank to pulling that stored water out and sending it into its network of water supply lines, said Darren Thompson, SAWS’ director of water resources.
The underground water bank, known as the ASR – aquifer storage and recovery – allowed San Antonio to avoid more stringent drought restrictions during the severe drought from 2010 to 2015.
After two abnormally wet years in 2016 and 2017, SAWS has stored enough water for more than half a year’s demand. SAWS will reverse the flow to the ASR for a week or two in preparation for a possible transition from recharge to production mode, Thompson said.
“We haven’t exercised the facility in a while, and we’re going to make sure everything’s fully operational,” he said. “It’s a good time to test it because unless we get rain in the next couple days, the Edwards will be in Stage 3 next week.”
At Stage 3, the Edwards Aquifer Authority can impose a 35 percent cutback when the aquifer level reaches 640 feet.
Typically, rain during May and June recharges the aquifer before the hottest summer months begin. This year, San Antonio received less than one inch per month, compared to the average of a little more than four inches a month.
“I keep making these predictions of things not likely to happen this year, and then they happen,” said Jim Winterle, Edwards Aquifer Authority director of modeling and data management who forecasts aquifer conditions.
This year the aquifer’s level started out relatively high: 666 feet on Jan. 1. It wasn’t a record high, but Winterle figured that, based on past statistics, the aquifer had only a 50 percent chance of dropping more than 12 feet by now.
Instead, the aquifer dropped about 25 feet as of Tuesday, with San Antonio getting half its normal amount of rain.
From January to June, it received only 8 ¼ inches of rain, compared to the average of 16 ½ inches over that period, according to National Weather Service data. In San Antonio, the three months from April to June this year were the third driest in 134 years of record-keeping, Nielsen-Gammon said.
Even with this aridity, San Antonio is faring better than the Texas Panhandle. There, the drought has reached extreme levels in some places, according to the Drought Monitor.
Reservoirs storing water in that part of the state are also running dry. They range from 39 percent full in Lake Meredith north of Amarillo to 1.3 percent of capacity at the nearly empty Palo Duro Reservoir, according to the Texas Water Development Board.
This is part of a larger pattern of drought across the Southwestern U.S. Large swaths of Arizona, Utah, Colorado, and New Mexico are in exceptional drought, with wildfires raging across tens of thousands of acres in those states.
At least in San Antonio, rain could bring some relief over the next few days. National Weather Service forecasters were calling for a 50 percent chance of rain Wednesday, with a slightly lower chance Thursday through Saturday.