Geology/Underground Water Resources for Farming Land
Im searching for Farming Land in Garmsar(city), Semnan(state), Iran(country). There are strict drilling laws here due to drouth. Every year the water level goes down ~1meter. Regardless I want to start a pistachio farm which requires ~35 liters per second of water per 100 hectars. I have found a property that has a permit for 28 liters per second of water excavation but the current well only has an output of ~14 ltrs per second. Im wondering if I buy this property and move the well (which is only allowed to move 100 meters north or south) will I be able to have a well with a higher output? What does it depend on how can I have an estimate of expected wateroutput (aftermove) before I buy the property? Please advise.
I had a college roommate from Iran, and remember the boxes of pistachios, pumpkin seeds, and other nuts he would receive from home. I work with a guy from Iran who came over before the war in the 1980's with Iraq.
You need to check a few things. If there is a well or neighboring wells, you need to see if you can determine the thickness of the aquifer. THAT determines how much water you can ultimately pump.
Aquifers, the porous, sand and grave layers that carry the water, are usually underlain by a non porous layer of clay or rock, and sometimes are sandwiched with another above. So in essence they are like a three dimensional pipe running in all directions.
Now, a well is drilled vertically into that layer and screened, that is a perforated pipe usually made of metal or plastic screen is put in that section and surrounded by sand in the hole, to keep mud and sand from clogging the pump. The height of the water in that interval dictates how fast you can pump water. If you pump faster than the water can move through the aquifer material, you will pump the well dry.
Have you ever had a thick drink, and drank it with a soda straw or drinking tube? Ever notice the dimple that forms around the tube? That is called the cone of depression See attached image.
When the rate of pumping exceeds the rate of recharge the well pumps dry and you start pumping mud or nothing at all.
So you need to get an idea of how thick the aquifer is, and the recharge rate.
Can you get the results of a pumping test on the well or a nearby well? See if the drilling companies in the area, or the government water agency have that information. It will tell you the maximum sustained pumping rate the well can support.
Also see if any hydrographic surveys, or ground water reports have ever been written for the area.
The topography is important too. You said something about moving the well. You don't want to be moving the well up gradient, in other words just like the surface, the aquifer containing the water may be slanted or tilted. The ground water should be running toward the nearest river or lake. If you have to move the well, move it in the direction of the nearest body of water since that is the direction the ground water is likely to be moving and the aquifer may be thickening in that direction. Any stream, or river represents the intersection of the ground surface with the ground water table.
I hope this helps you. Feel free to for more detail if you need it.