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) Surface Waters ...................................................................................... 4 St David Springs Surface Water Right Table ................................... 4 Groundwater .......................................................................................... 6 • Groundwater movement .................................................................. 6 • Water enters the aquifers ................................................................ 6 Well Table ........................................................................................... 7 Artesian Well ......................................................................................... 8 Confined wells ................................................................................... 9 Shallow wells ..................................................................................... 9 Deep wells .......................................................................................... 9 St David Springs Wells and Land Auction ........................................ 10
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St David Springs Lifestyle Farm Blocks
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Surface Waters Waters of all sources, flowing in streams, canyons, ravines or other natural channels, or in definite underground channels, whether perennial or intermittent, floodwaters, wastewaters, or surplus water, and water of lakes, ponds and springs on the surface.” Generally measured in Acre
Feet (Arizona Revised Statutes – 45-101) St David Springs Surface Water Right Table
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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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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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St David Springs Wells and Land Auction
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