Water is so important to Texas that we too may be singing that refrain. In this newsletter, we will explore the background of water supply in Texas and then get into how to use water sparingly.
Texas has nine major aquifers as shown on this map by the Texas Water Development Board. These aquifers can range from a few hundred feet below the surface to a thousand or so.
The blue zone in the Panhandle area is the Ogallala Aquifer. It is considered to have a finite supply of water because its origin is water from the Rocky Mountains and the recharge rate is so slow as to be nothing in our time frame. We spoke with a pumpkin farmer in the area near Clovis, New Mexico who had pumped from the Ogallala for years to irrigate his crops, but had to quit farming because the water level in the aquifer had dropped below the level of his wells. Travelling through this area shows that there are many farms pumping water almost constantly to irrigate crops. This aquifer holds a very large amount of water and the demand on it is principally agricultural.
Near home, we have two aquifers that provide water to individuals and cities--- the Trinity and the Edwards. The map shows the Trinity as dark green and the Edwards in dark blue. The Edwards Aquifer is nearer to the surface than the Trinity, and in the realistic view, is “owned” by the cities that sit on top of it and especially by the city of San Antonio. Private wells drilled in our area must be driven on through the Edwards and into the Trinity. Drillers are required to sleeve the well in the zone of the Edwards to prevent water seepage from the Edwards to the Trinity and prevent unintentional pumping from the Edwards. Water in the Edwards can be viewed as local water, that is, the aquifer is recharged by local rains which find their way into the karst formations[1] of limestone caves, sinks, ravines and underground streams through eroded holes in the earth. A photographer caught this dramatic video when he filmed a large stream of runoff water on the San Marcos River Foundation (SMRF) ranch. The runoff water is shown disappearing completely down a hole in the limestone terrain on its way to the aquifer. To see a video of this please click on the hotlink to the SMRF website and scroll down to the Cave Recharging Video. Click on the picture which will produce the video. If you are interested in areas of concern like Pumping Permits please see that article as well. This is a very hot item in Wimberley, Kyle and Buda. In fact Buda and Kyle are getting so concerned about their future water supply they are considering piping water from wells in the Carrizo aquifer to the east of us. There is little doubt that our underground water supply is diminishing.
Another area of concern is building anything on or near the karst formation areas. The Craddock Road Extension was recently turned down by the San Marcos City Council because of research presented by Diane Wassenich of the San Marcos River Foundation. These areas must be kept free for rains to recharge the aquifer. We also talked to a young woman in Wimberley not long ago who was very familiar with seeing developers building homes in her area of Woodcreek. She watched as they poured concrete down natural openings to karst formations before building the house foundations. So not only are there roads, driveways and foundations, there are also concrete plugs to hinder the falling rains from flowing to the aquifer.
Some of our lots here in BWR are sitting on cave karst formations according to some of the locals who have done work around here. They were telling us this back when we were building our house but we never really quizzed them as to where they were located. Have any of you seen any small sinks or caves on your property?
The four big springs of Texas (San Marcos, Comal, San Leon and Balmorrea) are holding their own because they are locally recharged and pumping has been limited so far. The Balmorrea spring is especially interesting.
Its water originates in the Davis Mountains and surfaces at Balmorrea where there is a huge concrete pool of crystal clear water. It’s great for swimming in midsummer because of the cool water, unlike the warm water of San Marcos springs. Other historically great springs, such as the Comanche Spring in Fort Stockton are dry and have been dry for years. If you visit the site of the Comanche Spring in Fort Stockton, you will find a large (and empty) concrete structure that was once full of fresh running water that provided local recreation for the area. The Comanche Spring no longer exists because of the extensive pumping from the Ogallala formation to irrigate farm lands in the area.
Gunnar Brune’s book titled Springs of Texas (Vol. 1) is a compilation of the historical flows of all the springs in most of the counties. It shows that spring flow is diminishing in all areas. In fact 25 % of the 281 known significant and historical springs were dry by 1975.
Quick quiz: How many natural lakes do we have in Texas? Unlike states in the Great Lakes area, we have only two that are considered natural. On the other hand, we have many dams on local streams and rivers constructed principally for flood control and water storage. Managing the water levels behind the dam is always a challenge. If the dam is full of water, it has no capability to hold back the flow and stem the flooding downstream. If the water level is purposely lowered, the availability of water for cities is greatly reduced---and people who have built homes on the shore begin to complain about property values. Remember Lake Austin a few years ago? Although we have almost two hundred significantly sized water impoundments (significant meaning larger than stock tanks) we only have two lakes, and in my mind, one is questionable as to its “naturalness”. One is Green Lake to the south of us and Caddo Lake near the upper border with Louisiana. Caddo Lake could easily be judged not natural because it appears to have formed in more recent centuries from blockage of the channel with fallen trees and brush.
Another concern with water level management is how to regulate the flow of fresh water to those downstream stakeholders, like farmers, like the many small towns, like the ecosystem where the fresh water meets the salt water of the Gulf. The demands on river water are probably greatest on the Colorado River where there are several dams above Austin. The downstream effect of Austin’s usage can be quite evident in the summer months when you cross the river at the bridge in Fayetteville. The water here is usually stagnant, green and opaque.
Some of our rivers have other limitations. The Brazos for example, at low flows in the dry season has a salt content problem. The salt comes from the Salt Fork in the panhandle area. Houston was once talking about storing water from the Brazos in an area to the west of Simonton, but that plan seems to have been set aside, maybe because of the salt levels.
All the facts on water availability and usage in Texas suggest we use water sparingly, even if our supply seems unlimited. That drives us in the direction of low water usage plantings, enjoying native grass that is sometimes brown from lack of water, low flow faucets, etc. Rainwater collection is helpful as well and it may well avoid state regulation of a well in some future time.
Books/Newspapers
Joe Urbach, Hays County Master Gardener instructor, revealed in his July 8 column in the San Marcos Record the dark side of the Hummingbird moth we loved to watch sipping nectar from our larkspurs. Turns out this nefarious moth is the parent of the well disguised tomato worm! He went on to describe that with a $10 black-light flashlight the worms can be easily discovered and dispatched in the tomato patch after dark.
Sightings
One night as we were having dinner a large bird with spread wings just skimmed the window, descended and then circled around to come to rest on the head of a birdbath statue. It was a Poe-ish moment, but the Turkey vulture (Cathartes aura) was a lot bigger than a raven. It spent awhile looking around but its intended victim had apparently disappeared so it went on its way.
Our living to the west in Bandera County provides some experience with Axis deer. Axis deer are an imported species to provide hunting on the big game ranches. Texas Parks and Wildlife view the Axis deer as strong competitors of the native White Tailed deer because of their browsing habits. One day we looked out the back and there was one of these in the back yard. You can easily identify this animal because of the white spots on its sides. At first glance you might think this is a white tail fawn, but this animal has permanent white spots into maturity. There is no hunting protection for the Axis deer. We are told the meat tastes better than the White Tail.
The Lotebush (Ziziphus obtusifolia) by our front door is now festooned with tiny yellow flowers that the bees love and a garland of Snake-Apple vine (Ibervillea Lindheimeri). The only other plant we knew existed was on the fence line along Hugo Road. We haven’t seen it in years, maybe it got the heave ho during fence rebuilding. If you see one please let us know. The possums and the raccoons apparently like the fruit because at just the right time of ripeness, they all disappear from the vine.
We make an unofficial bird count at midyear and year end. Our midyear list this year totals about 30 birds. It is posted in Natures Gallery (the top menu tab of the BWR website).
Speaking of birds, we have a CD of the bird calls of this area. Should any want a copy of this, just let us know and we will get a copy to you.
R & D Tusch
[1] http://www.texasspeleologicalsurvey.org Press Ctrl and click on the link. Check out Texas karst and Karst totals by County and see that Hays has 925.
