About Us

Water Supply Options for Clear Springs Park Property Owners

Introduction
With the ongoing and extensive drought combined with the booming population in the Bulverde and Central Texas area, concerns about our wells and area water supplies abound. Reports and examples of wells running out of water or losing significant capacity are becoming more common within our Clear Springs Park neighborhood and in the surrounding area. This document will attempt to give an understanding of the aquifer that our neighborhood wells draw from, how our wells are constructed, and how they are impacted by drought and increased demand.
Current Situation
Clear Springs Park (CSP) is comprised of 246 individual properties. Currently, there are around 200 properties with homes. Except for a few properties that meet their water needs through rainwater harvesting, all properties have their water supply provided through individual property wells. There is no municipal water supply available within our neighborhood. In general, the depth of most of our wells are in the range of 700 feet to 900 feet below ground surface. Most wells are equipped with a submersible pump that lifts approximately 10 to 15 gallons per minute from the aquifer to the ground surface. Using standard water industry usage metrics of approximately 50 to 75 gallons per person per day, it can be assumed that each of our properties consume approximately 125 to 190 gallons per day of water. Extrapolating these values to our overall neighborhood, CSP utilizes between 9.1 million gallons per year to 13.7 million gallons per year of water.
As noted above, there currently is no municipal water supply service to our subdivision. The SAWS water distribution system currently extends up to our south boundary. As you may have seen, there is a large blue tank at the top of the hill just prior to our first entrance. This tank is called the Indian Springs tank. This site only contains this water storage tank. There are no wells on the Indian Springs tank site. The closest SAWS wells are on the opposite side of Hwy 281.
The neighboring subdivisions of Riata Ranch to the north and Country Place to the west also utilize personal wells to supply their water needs. The area to the east of CSP is largely undeveloped preserve property.
Our Wells
This discussion is not intended to provide specific information regarding individual wells within Clear Springs Park but rather to provide an overview of the general nature of our CSP neighborhood wells. Information that follows was compiled from public records found on the Texas Water Development Board website and from well drilling records provided by CSP residents.
Our wells draw from the Trinity Aquifer. This is one of Texas’ major aquifers that extends from the San
Antonio area north through the Blanco/Lampasas/Llano/Stephenville portion of the State. The Edwards Aquifer is a well-known aquifer in the San Antonio area but it does not extend into the CSP area. It is important to note that CSP is located near the southern extent of the Trinity Aquifer. While the Edwards Aquifer can exhibit rapid recharge during rain events, the Trinity Aquifer recharges very slowly. It has been said that only 4 to 5% of water that falls as rain over the area ends up recharging the aquifer. Many of our well reports mention our wells going into Cow Creek. This is a sub-aquifer of the Trinity. Our wells are low producing wells due to the nature of the geology that they pass through. In the construction of larger capacity wells in other areas, well drillers look for thick layers of sand in which water co-exists. In the case of our wells, these thick sand layers do no typically exist and water more typically seeps into the well column via cracks and fissures in the underground geology. Because of this geologic limitation, ourwells are more susceptible to drawdown due to extensive use and slower rebound following that use. This type of geology and aquifer structure helps to explain why one neighbor may not have any well supply issues but another well in close proximity experiences frequent supply issues even if drilled to the same elevation. The Cow Creek Groundwater Conservation District provides a wonderful video (http://youtu.be/DWgPjPI7D7s) that helps to explain the significant nuances between the Edwards Aquifer and the Trinity Aquifer and how those nuances impact individual wells.
While our neighborhood is filled with hills and valleys, the general slope of the land is from west (Elev 1156 at south entrance and Elev 1220 at North entrance) to east (Elev 970 at the park area). The underlying aquifer also slopes from west to east. While both the ground surface and the aquifer generally slope from west to east, they are not parallel. It therefore is important to correlate your properties ground surface elevation and the predominant water surface elevation in close proximity wells to get an idea of the depth to water for your particular property.
CSP began to be developed as a subdivision in the early 1980’s. Without going to extensive lengths to try to retrieve data from the earliest well construction in our neighborhood, we have 8 data points of wells constructed in the 1990’s. All of these wells are along Mark Alan. Data from these well reports show the following:
Average ground surface elevation = 1207
Average depth of well = 746 feet
Average elevation of bottom of well = 446
Average depth to water surface = 402
Average elevation of water surface = 791
Average depth of submersible pump setting = 607
Average elevation of submersible pump setting = 678
As noted previously, given the characteristics of the Trinity Aquifer and in particular the Cow Creek subaquifer, one needs to be careful about making too many generalizations and assumptions between wells and especially between wells constructed decades apart. However, I think there are some observations that can be made of some more recent wells constructed along Mark Alan.
Average depth of well = 890
Average elevation of bottom of well = 280
Average depth to water surface =
Average elevation of water surface = 760
Average depth of submersible pump setting =
Average elevation of submersible pump setting = 350
From this information I think it can be concluded that well drillers are currently drilling well approximately 140 feet deeper, water levels are approximately 30 feet deeper, and pumps are being set approximately 330 feet deeper than in early CSP well construction.
Use of Cisterns
Cisterns (or water storage tanks) come in a wide variety of sizes and provide an array of benefits to property owners. These benefits include reducing impact on the aquifer at the well, water storage, and improvements to water quality. As stated earlier, our wells in CSP are low-capacity wells producing around 10 to 15 gallons per minute. When the water demand at our home exceeds this pumping capacity, we begin to see a reduction of pressure. If the increased water demand continues for an extended period of time that is totally dependent upon the inflow rate of aquifer water into the well column, the water level in the well column can fall below the operating level of the submersible pump. This pressure reduction or complete loss of water can be overcome by adding a cistern into the well pump discharge piping and also including a booster pump to pump the stored water into your home. A cistern can be purchased in a wide variety of sizes ranging from 150 gallons to several thousand gallons. For most households, a 150-gallon tank may provide 1 or 2 days of storage. A 3,000-gallon cistern may provide approximately 15 to 20 days of water storage.
A cistern can also provide improvements to water quality. Since the cistern provides a space that is open to the atmosphere (not contained within piping from the well to the faucet), natural processes can begin to strip contaminants such has hydrogen sulfide and iron from the well water.
Looking Forward
It is difficult or maybe even impossible to predict how our existing wells will continue to operate in this time of drought and increasing demands on the Trinity Aquifer. There are no quick, easy, or inexpensive solutions if your well loses capacity or even worse goes dry. However, there are some potential solutions. While a professional should be consulted to obtain actual costs for your particular situation, the following options are provided to give you an idea of possible alternatives. In order of increasing costs:

• Potable water deliveries into cistern. While partial truckload deliveries can be provided, the most economical delivery is a full truckload. A typical truckload is 1,500 gallons. In today’s market, a full truckload delivery costs on the order of $150.

• Add cistern and booster pump. While there are many factors that impact the cost of installing a new cistern and associated foundation and a new booster pump system, a new cistern and booster pump system cost is in the range of $10,000 to $15,000.

• Construct rainwater harvesting system. Similar to the construction of a cistern and booster pump system, the cost of a rainwater harvesting system can vary widely. Depending upon the level of use and the safety factors desired to avoid use of well water or imported deliveries, a RHS would likely consist of 20,000 to 30,000 gallons of water storage, possibly new booster pump system, and water treatment components consisting of filtration facilities and ultraviolet disinfection system. The cost of a RHS is in the range of $25,000 to $45,000.

• Drill a new well. The cost to drill a new well to approximately 1,000 feet and install a new submersible well pump but utilize all other existing well system components is in the range of $40,000 to $50,000.

• Connect into SAWS distribution system. CSP is within the SAWS service area and they have indicated that they can provide service to either individual property owners or the entirety of CSP. The costs of connecting to the SAWS system is not quantifiable at this time as it is highly dependent upon the number of properties that choose to connect to the system. Currently, the connection fee is on the order of $7,400. However, a much larger cost is the construction cost to build the pipeline infrastructure. The CSP subdivision property owners or portion thereof would need to share the construction costs to build the pipelines throughout CSP. SAWS would need to be consulted to obtain estimates of probable construction costs.

Researched by David Timmermann
May 2024