Wednesday, October 12, 2011

Texas Drought 2011 and a tale of two summers

Joppa residents at Trinity River Wetland Cells September 2011

With summer in the rear view mirror maybe now would be a good time to see what impact the historic Texas drought of 2011 had on the Great Trinity Forest. The summer of 2011 broke over a dozen long standing records in Dallas. Most 100 degree days. Highest night time temperatures. Highest daytime temperature on multiple dates. Smashed many of the long standing 1980 records and many of the epic 1950's temperature records. Perhaps the only record of note not broken was the 1980 record for most consecutive days at or above 100 degrees. 2011 was one day short of a tie.

The lack of rain and the heat were a one-two punch knockout across Texas. The duration of the drought coupled with a drier than normal 2010 spelled disaster across the state. Large agricultural losses to farmers, the livestock ranching industry in near ruins tell an awful story. One that will be told decades from now.

Prickly Pear Cactus in Great Trinity Forest on the 5980 Trail
While the economic losses are a known quantity by now, few can guess what impact the months of scorching desert like climate will have on the trees and wildlife in the Trinity Riverbottoms. The "Great Trinity Forest" can usually suck up a regular Texas summer. Much of the acreage lies in ancient alluvial soils that retain moisture like a sponge. Not this year. By early July I could tell that the "sponge" had gone dry. Many of the pocket ponds and lakes began to dry at an alarming rate. Some as much as a vertical foot per week. By mid-July many of the trees started to show stress, casually dropping leaves that began to blanket the forest floor. No real concern since the water loving cottonwoods and willows will start dropping leaves at the drop of a hat. By the end of July, the native pecans, burr oaks and red oaks began showing signs of stress. That is a real concern. Those trees have deep tap roots and to see them stressed in that way means that the moisture deep underground is beginning to disappear. Perhaps one of the only plants I have found to be thriving down there is the Prickly Pear Cactus(see inset). This particular cactus is about the size of a VW bug and easy to spot on the "5980 Trail". Enormous fruits for such a hot summer. Even it seemed to be heat stressed some with a milky discharge coming from the fruit.

The citizens of Dallas are insulated from many of the draconian water restrictions other cities in Texas face. During the last great drought of the 1950s, Dallas was nearly caught flat footed without a way to provide adequate water to residents. As a result, Dallas built over a dozen reservoirs in North and East Texas to provide a reliable water supply for the future. While cities like Austin and San Antonio faced a summer without being able to fill a swimming pool or even washing their car in some instances, Dallasites could water as much as their wallet could handle. Looking around Dallas one cannot really see what happened unless you visit a part of town without a sprinkler that turns on at 3am.

Below are some photos taken from places throughout the Great Trinity Forest about one year apart. In most cases the differences between the summer of 2010 and 2011 are rather dramatic. 2010 was also a hot summer. DFW was in a rain deficit until Tropical Storm Hermine stalled over North Texas in September 2010 dropping over a foot of rain.

Trinity River Wetland Cells

Trinity River Wetland Cells September 11, 2011

Trinity River Wetland Cells August 2010

The Trinity River Wetland Cells sit roughly between I-45 and Loop 12 parallel to the main Trinity River Channel. They are partially fed by discharge from the wastewater treatment plant. Using a series of water level gates, the water can stay at a constant depth year round. During periods of river flooding these lakes perform a vital role of slowing down flood water. In normal conditions the lakes serve as a biofilter for discharge before it heads south. A month or two from now the water in the Trinity wetland cells will be in a Houstonian's glass of water.

To see the dramatic feast/famine nature of the drought check out the photo below. The plants in contact with the water are green while the plants left high and dry are all but dried potpourri. In the background are ash trees I believe. Apparently they do not drop their leaves when they go dormant. The result is what looks like fall in New England or turning aspen trees at Crested Butte. Unfortunate that this is not the case. Those trees were cooked. Baked.

Drought starved trees at Trinity River Wetland Cells sunset October 1, 2011

McCommas Bluff

McCommas Bluff September 2011

McCommas Bluff August 2010

McCommas Bluff sits in the far southeastern portion of Dallas. Here the land is a sandy loam sitting atop limestone. The trees are a mix of post oak, live oak and even pine trees do well here in the sandy acidic soil. Much different than the rest of Dallas in that regard. Along the bluffs some of the older smaller trees show heat stress. A false autumn color peppers the landscape. The lush green of 2010 is nowhere to be found and the native grasses one usually sees are replaced by dust and bare dirt. The native grass really never even got tall enough to go to seed this year. An issue that might not crop up until the spring of 2012.

McCommas Bluff is one of the few places where it is easy to see how the low flow of the Trinity has left things high and dry. Also one of the few spots left in Dallas where you can find a hard limestone bottom in the riverbed. Record Crossing, Miller Crossing and Eagle Ford also had hard bottoms but are now long gone. At McCommas Bluff the river stayed low enough all summer for weeds and grasses to spring up in the old riverboat tie-down.

McCommas Bluff riverboat landing in Trinity River Channel August 2011

McCommas Bluff riverboat landing in Trinity River Channel September 2010

Not only can you see the how the exposed riverboat landing sat exposed during the summer, one can also see how the drought stressed trees along the bluffs began to go dormant. The upper photo was taken August 6, 2011. I think it was close to 110 degrees when I took that photo.

Texas Horse Park

The future site of the Texas Horse Park. Long used as a grazing pasture the land is peppered with mesquite and cactus. Many of the ponds at the Texas Horse Park went dry by the end of July.

Texas Horse Park September 2011

Texas Horse Park August 2010

Texas Horse Park trail from Trinity River Audubon Center September 2011

Texas Horse Park trail from Audubon Center late June 2010

Scyene Overlook White Rock Valley

Scyene Overlook September 2011
Scyene Overlook August 2010

One of the stark contrasts of the 2010 and 2011 summers can be seen at the Scyene Overlook located near Scyene and Jim Miller in East Dallas. Scyene Overlook offers unobstructed views south to Wilmer, Hutchins and Cedar Hill. The photos above are looking out over the White Rock Valley across Bruton Road and US 175. The water tower in the upper photo is near I-45 and Carbondale near the Joppa Community. The photo shows hundreds of trees that have defoliated from the heat. Many are mature pecan, walnut and oak. I would think many of these trees have gone dormant. Since the trees lived through the drought of the 50s and the similar 2011 heat of 1980, I would imagine they will rebound by next spring.

Lemmon Lake

Lemmon Lake Summer 2009, Trinity River on immediate right, Loop 12 in extreme upper right hand corner

Lemmon Lake Dried Lake Bed  August 2011

Alligator Gar remains eaten by feral pigs at Lemmon Lake August 2011

Storks, Ibises, Spoonbills, Egrets at Lemmon Lake
Lemmon Lake is long forgotten relic of generations past. Once a playground for wealthy Dallasites, the lake saw its heyday about 1900. So popular back then that a small train station named Lakewood was built where River Oaks Road crosses the train tracks today. Over the last 40 years the forest surrounding it crept up to its shore cloaking it from the outside world. Maybe the only notable thing to happen there in the last 30 years was a Dallas Police helicopter crash landing after what was later determined to be horsing around. Slowly silting in, the lake now serves as a refuge of sorts to rare birds that one is more likely to see on the Amazon, not the Trinity.

It will take a flood that rises half way up the levees upstream in Downtown to refill the lake.

Historic Springs

The Great Trinity Forest holds two springs of historic note, Honey Spring and White Rock Spring. As the crow flies they are only 1 1/4 mile apart. Honey Spring currently sits in the heart of the Joppa Freedman Community on the west side of the river. At one time the spring served as the sole water source for the community that built around it. In the 1800s the MKT railroad built a water station near the spring. At the time, the spring was considered a reliable water source south of the Trinity. It was here at Honey Spring in the late 1800s that some Spanish Conquistador gear was found buried. Helmet, axe, chest plate.

The spring went dry in August.

Honey Spring Joppa October 2011

With Honey Spring going dry this summer I thought that White Rock Spring would share a similar dry fate. I have a previous blog posting about White Rock Spring here: Sam Houston's Treaty Camp on White Rock Creek. White Rock Spring sits on the east side of the Trinity River in the middle of an unassuming field surrounded by a clump of trees. My last visit to that area was on Labor Day. The previous 3 months not an inch of rain had fallen anywhere in that zip code. In the previous 5 months there had not even been a storm with real runoff that could recharge a spring. I'm not sure there was even a cloudy day in that 3 month stretch. Just oven baking heat. To reach the spring from Rochester Park(now called William Blair Park after Elite News founder William Blair) usually requires a knee deep fording of White Rock Creek and some sketchy tip toeing around some swamp areas infested with alligators. The drought turned what is usually a 20 minute slog of cussing and second guessing into a 2 minute breeze of traverse.

Much to my amazement, White Rock Spring(also known as Big Spring on some very old maps) was running strong and cool. Video below:

Spring strength is measured in flow, liters per minute. I would say the flow was about 10 liters per minute of flow. More than a couple average garden hoses put together. I'm impressed. Somehow, despite a dry winter, spring and summer, that spring still flows.

What lies ahead

Beats me. I'm not a forester or biologist. The effects of this summer will be felt for years. I guess the first signs will be if the wintering birds decide to stick around.

For about a month this summer I was certain some idiot would set the Trinity on fire. Watching the rest of Texas burn in wildfires from the Sabine to the Pecos I thought for sure some firebug would torch the woods. In the White Rock Valley, the mountain cedar just smelled like it was already smoldering in the early evening heat. In Rochester Park the air was thick with hay dust that could have sparked a massive blaze. Just absolutely amazed that did not happen. I can only chalk that up to a complete absence of people there.

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