This book is all about surface and ground water at St David Springs Arizona
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Table of Contents – (Click on the topic of your choice) Water Runs to St David Springs, an Oasis in Southern Arizona ....... 2 The 1887 Sonoran Earthquake .......................................................... 3 Development of Artesian Wells ........................................................ 3 Groundwater .......................................................................................... 4 • Groundwater movement .................................................................. 4 • Water enters the aquifers ................................................................ 4 Well Components .................................................................................. 5 St David Springs Well Table ................................................................. 6 Irrigation well 450 GPM Artesian 45 GPM no pump .....................6 Artesian Well ......................................................................................... 7 Confined wells ................................................................................... 8 Shallow wells ..................................................................................... 8 Deep wells .......................................................................................... 8 Lifestyle blocks Defined ....................................................................... 9 Water Runs to St David Springs, an Oasis in Southern Arizona St. David Springs is situated approximately 8 miles south of St. David, Arizona, and nestled within the ecologically rich and geologically diverse San Pedro River Valley. This area is encircled by several notable mountain ranges and hills and is at the confluence of the surrounding mountain drainage, contributing to its unique landscape and Abundant Water.
• Dragoon Mountains (East) • Whetstone Mountains (West) • Huachuca Mountains (Southwest) • Mule Mountains (Southeast) • Galiuro Mountains (Northeast)
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For those seeking a blend of rural tranquility near the City of Tucson, St. David Springs offers a unique opportunity to develop a Lifestyle Farm Block with a custom home in a water-rich, scenic environment. The surrounding mountains and geological features not only define the scenic beauty of St. David Springs but also contribute to its ecological diversity and historical significance. 8 Miles north, St. David, Arizona, a historic community in Cochise County, was founded in 1877 by Mormon settlers. Its origins trace back to the Mormon Battalion's 1846 march through the San Pedro River Valley during The 1887 Sonoran Earthquake, with an estimated magnitude between 7.6 and 8.1, profoundly impacted St. David, Arizona, particularly its water systems. Before the earthquake, St. David featured marshlands and water pools. The earthquake's seismic impact changed the surface water accumulation, especially in the St David Springs area with fresh artesian flowing water and ponds The earthquake also caused the San Pedro River to sink underground in certain areas, disrupting traditional surface water sources and necessitating the development of new water supply methods. Development of Artesian Wells the Mexican-American War. The 1887 Sonoran Earthquake
In response to the altered hydrology, local residents began drilling artesian wells. Notably, in 1894, the McRae brothers discovered a significant artesian water source at a depth of 276 feet, yielding 30 gallons per minute.
This finding contributed to the St David Springs water source. There are 30 wells on the Lifestyle Lots of the St David Springs. One well in particular delivers 45 gallons of sweet water per minute without the aid of a pump
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Groundwater • Groundwater movement in the basin 6 miles south of the Town of Saint David at and within St David Springs is from the higher elevations in the mountains toward the valley and then northwest along the riverbed. Groundwater moves readily between the younger and older basin-fill units and between the streambed alluvium and the younger basin-fill unit. In the confined areas, water from the artesian aquifers may leak upwards into the water-table aquifer. In 1990, the Arizona Department of Water Resources estimated the total groundwater in storage in the Upper San Pedro basin to be 59 million acre-feet. Groundwater is water that is lifted to the surface by a well. • Water enters the aquifers by mountain-front recharge and by streambed infiltration. A smaller amount enters the basin as groundwater underflow from Mexico. Mountain-front recharge consists of surface runoff that flows off the bedrock in the mountains. It infiltrates into the permeable basin-fill sediments on the alluvial fans surrounding the mountains, and eventually reaches the water table. Streambed infiltration occurs when surface-water flows in the San Pedro River channel and its tributary washes infiltrate the coarse streambed sands down to the water table.
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Well Components Knowledge of the main components of a private water well system. A drilled well can reach confined aquifers, even at significant depths. A combination residential and irrigation well water system includes many components. The main components of a drilled well include
1. The wellhead: visible above ground. 2. The well is a bored hole connecting the surface to the groundwater. The casing lines the well to keep material from collapsing into it. 3. In this illustration, a submersible pump delivers water to the surface. 4. A screen at the bottom of the well filters out loose soil, such as sand. 5. A pressure tank provides temporary water storage in a single speed system although a variable speed motor can bypass the storage tank for irrigation. 6. The water is pumped to the surface using a power source, usually electricity.
7. Artesian wells at St David Springs that flow water above the surface are known as “flowing artesian wells. Many artesian wells flow above the surface and others rise near the surface. Those that rise near the surface are artesian but not flowing artesian. Artesian wells significantly reduce water pumping cost. 8. You do not need to lift the water from the very bottom of the well. Water only needs to be lifted from the static water level to the discharge point. The static water level is the level to which water naturally rises in the well when it’s not being pumped.
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St David Springs Well Table Irrigation well 450 GPM
Artesian 45 GPM no pump
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Artesian Well An artesian aquifer is a confined
aquifer containing groundwater under positive pressure. This causes the water level in a well to rise to a point where hydrostatic equilibrium has been reached. This type of well is called an artesian well . Water may even reach the ground surface if the natural pressure is high enough, in which case the well is called a flowing artesian well
An aquifer is a geologic layer of porous and permeable material such as sand and gravel, limestone, or sandstone, through which water flows and is stored. An artesian aquifer is confined between impermeable rocks or clay which causes this positive pressure. The recharging of aquifers happens when the water table at its recharge zone is at a higher elevation than the head of the well. Fossil water aquifers can also be artesian if they are under sufficient pressure from the surrounding rocks. This is similar to how many newly tapped oil wells are pressurized.
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Confined wells and artesian conditions in the regional aquifer occur near the center of the basin. In the case of Saint David Springs, 6 miles south of the town of St David, fine-grained beds restrict vertical groundwater movement. There are two areas where confined conditions are found:
Shallow wells drilled deeper than 100 feet in or near the San Pedro River south of Saint David encounter artesian conditions. Artesian wells that flow water above the surface are known as “flowing artesian wells. Many artesian wells flow above the surface and others rise near the surface. Those that rise near the surface are artesian but not flowing artesian. Deep wells of 800 feet depth puncture the clay lens originating at the Dragoon mountains. These wells lift water to near or above the surface due to the hydraulic pressure of an enormous lake that lies below the lens.
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Lifestyle blocks Defined : Lifestyle Blocks are small rural properties, typically between 5 to 60 acres that are used for a mix of residential living and small-scale farming or family lifestyle agriculture. Lifestyle blocks are often purchased by people who want a country lifestyle and an atmosphere to aid in the development, responsibility and work ethic of young children, but the owners don't necessarily depend on farming as their primary income source. Essential to a Lifestyle Block or Homestead as an assurance of a plentiful and perpetual water supply as water is a scare and essential ingredient to farms and ranches Subdividing property in Cochise County is
regulated by the Minor Land Division Regulations and the Cochise County Subdivision Regulations. The minor land division process applies when a large parcel is divided into 5 or fewer smaller parcels, any of which is 10 acres or smaller. The County subdivision process applies when a large parcel is divided into 6 or more smaller parcels, any of which is 36- acres or smaller.
Purpose of the Minor Land Division Process The purpose of the minor land division process is to divide a large parcel into smaller lots for sale in a manner that: • Promotes orderly growth and sensitive design; • Ensures all lots are accessible by car, have appropriate easements and
can meet the minimum requirements of underlying zones. https://www.cochise.az.gov/ development-services/home
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