Submerged in Drought

Floating seemingly weightless against a black backdrop speckled with colors and dots of light, Earth is the only planet with liquid water on the surface.

Water covers about 71% of Earth's surface, and almost all of it – 96.5% - is salt water, according to NASA. Of all the water on the planet, just 3.5% is freshwater we can drink. Most of that – 68% - is trapped in ice and glaciers.

And we need it to survive, which makes extended droughts such a daunting situation.

Because we in Texas know that droughts are as certain as the floods that follow, weather extremes are nothing new. Floods will follow droughts. Droughts will follow floods.

So, if we know a drought is coming – even eventually – we know that water conservation and water management will remain important whether we're in a drought or not as we look to preserve and protect this vital resource.

Narrowing in

According to John Honoré of the Texas Division of Emergency Management State Drought Preparedness Council, it would take 15 inches of rainfall for much of the eastern, central and upper coastal areas of Texas to return to normal conditions. The amount is 12 to 15 inches in the Edwards Plateau and Southern Texas. It is 9 to 12 inches in the Trans Pecos, the High Plains, and the Low Rolling Plains.

"These are by far the worst Palmer Drought Index rankings I have seen since taking over the Subject-Matter Expert role for the Drought Preparedness Council five years ago," Honoré said. The Palmer Hydrological Drought Index (PHDI) is an agricultural measurement of drought used as part of a suite of indicators developed by the U.S. Weather Bureau.

Let's take a look at drought conditions in the Brazos River basin and the Brazos River Authority water supply.

It's important to know that, like a snowflake, no drought is the same, said BRA Senior Hydrologist Chris Higgins.

Of course, drought isn't pretty like a snowflake.

It may seem tempting to try and compare the current drought conditions to the last big drought (2011-2015) and even the drought that launched the construction of our water supply reservoirs (1950s). However, there are too many different characteristics of drought to compare them too closely.

As of June 23, the state's water supply reservoirs were 76.5% full, according to the Texas Water Development Board. One year ago, that number was 85.5% full. Continued record high temps have resulted in 100% of the Brazos River basin now experiencing some level of drought. With the lack of rainfall and ongoing use of stored water supply, the BRA System was 87% full as of June 30, 2022.

The combined BRA water supply system holds roughly 2 million acre-feet of water when full, Higgins said. Last year at this time, the system was 99.7% full. But, that was somewhat of an anomaly, he said.

"We had an unusually wet summer (last year), so our system was fairing pretty good," Higgins said. "Typically in the summer, we'll experience some losses due to (water supply) demands and evaporation being so high. In a typical Texas summer, we just don't get a lot of rain regardless of whether we're in a drought or not - so last year was kind of unusual."

From just a water supply perspective, this year is faring better than 2011, Higgins said. In June 2011, the BRA water supply system was 83% full, compared to the current 87% full.

Additionally, the need for downstream water supply is different this year from 2011. The BRA started releasing water for downstream, lower basin customers around mid-April in 2011, while that process wasn't needed until June 6 this year, Higgins said.

"When you're talking about drought, there are all kinds of things that are involved," Higgins said. "Every drought is different. Inflows or water that actually enters the reservoirs are actually less this year from January through May than they were in 2011. This year inflows are less. Yet, we made it farther into the drought before needing to release water to those downstream in need. A lot of the rain in 2011 fell above (upstream of) the reservoirs, while most of the rain so far this year has fallen below (downstream of) many reservoirs. It kept the river wet. It kept the river flowing. But we weren't getting those inflows into the reservoirs."

When lake levels fluctuate, it means the reservoirs are doing what they were built to do, Higgins said.

"We're in great shape," Higgins said. "This is why we exist. This is why the BRA was created. Our water supply reservoirs store water in wet times, so it's available in droughts. Our water supply system is operating for the purpose that it was initially intended to do."

'Nature is complicated'

When managing the water supply of the Brazos River basin, hydrologists must look at the system as a whole, whereas lakeside homeowners, for instance, may only be concerned about their local lake.

"We're trying to make sure the water needs of everyone in the basin are met," Higgins said. "There's a much bigger picture than one neighborhood or one city or one reservoir."

The 1950s drought was considered the worst drought on record for most of the basin until 2011 came along. While the 1950s remained the drought of record for the central and lower portion of the Brazos River basin, 2011 became the new drought of record for the upper portion of the basin from Lake Possum Kingdom down to Lake Whitney.

The Brazos River basin crosses different climatic boundaries. The upper portion is a semi-arid, almost desert-like climate, while the lower portion of the basin, near the Gulf of Mexico, has a more sub-tropical climate, Higgins said.

Besides how much, where, and to what intensity rainfall hits the basin, another factor in drought conditions is the wind.

Wind is a big driver as it significantly increases evaporation, Higgins said. High winds in 2011 were a real stressor on the water supply reservoirs, increasing evaporation rates, he said. Those winds haven't been seen much this year.

"Nature is complicated," Higgins said. "It's complex. And we have to approach it that way. We have to approach it as every drought is different and plan that way with the tools you have available to you."

Currently, all 11 water supply reservoirs in the BRA system are facing a Stage 1 Drought Watch. The declaration came after multiple areas throughout the basin met triggers set within the BRA Drought Contingency Plan associated with the PHDI.

The goal of the Stage 1 Drought Watch is a voluntary reduction of five percent (5%) of water use and to raise awareness of the developing drought situation.

If the Brazos River basin does not receive significant rain at the right intensity and in the right areas of the basin, there's always the possibility of the need to declare a Stage 2 Drought Warning. This stage calls for efforts to reduce water use by 10% or more.

In the worst-case scenario over the next two months, Lake Proctor is the only water supply reservoir currently forecasted to enter Stage 2. The last time a water supply reservoir was in Stage 2 in the Brazos River basin was in October 2018 at Lake Proctor. That reservoir is somewhat isolated, has a smaller watershed and can feel drought effects more heavily than some of the other lakes, Higgins said.

The BRA's Drought Contingency Plan provides for several lake level triggers based on four levels of potential drought conditions. Originally adopted in 1989 under state requirements, the plan is intended to help preserve and extend water supplies during drought conditions and includes strategies for temporary supply and demand management.

Since the plan's adoption, the BRA has only entered Stage 4, the highest level, once due to drought conditions, which occurred in 2015. At the time, those receiving water supply from Lake Proctor were asked to cut back water use in accordance with BRA’s Drought Contingency Plan.

"The whole basin was kind of in a mild drought, but that part of the basin was feeling it worse than others," Higgins said.

All it takes is a few rain events or a tropical storm to change everything, Higgins said.

You never really know what to expect with Texas weather.

Over the past 18 months, Texas experienced the coldest winter period since the 1980s (February 2021); the warmest December ever recorded (2021), and one of the hottest springs ever recorded (2022), said Chris Coleman, lead meteorologist for ERCOT, the Electric Reliability Council of Texas.

The current La Niña, the weather condition thought to be the cause of drought conditions through much of the U.S., is the strongest since 2010-11 and is currently forecasted to continue through at least the fall season.

According to the June 23 Southern Plains Drought Status Update from Drought.gov - There is potential for drought intensification and expansion in Texas this summer. The latest forecasts for winter 2022–23 indicate that another La Niña is slightly more likely to occur than a neutral pattern this winter, and an El Niño – a reversal of drought condition -- is unlikely. This means another dry winter is possible.

As lake levels continue to decline, it's more important than ever to conserve water.

The lakes will refill. Texas' weather is a cycle.