Most people assume you can ...

Most people assume you can pump groundwater or aquifers for a supply but this is degrading fields if used for crops, if mineral-salt build-up gets to a certain point the land is lost to agriculture. This brings into focus the effects of dry areas getting drier as the planet heats up as a general rule. ... ¶ So recycling water is becoming as important as drilling for water as a supply, the need in a desert is for water low in minerals and that's exactly the opposite of what most arid water supplies provide, it's like sea-level, soil salination is a steady but slow process that's very hard to reverse and affecting many areas. ... ¶ And the need is for more than just water, people also need fuel, denuding forests is common in too many places so a large factor for reducing groundwater supplies by reducing drip-rain produced by condensation on plants that adds significant water to soils, this effect doubles rainfall in many areas in available water to soils. Then, to get good crops takes organics and soil communities, good soil can be built up and it holds far more moisture than fertilized dirt. ... ¶ This leads me back to the need for at minimum community level wastewater treatment, a way to use the nutrition in the water to grow algae as they clean the water as they grow and given the time make full recycling practical without extensive filtering. People are already making fuel from algae in blue-tarp lined pits, they need a coherent system that does that as a part of cleaning the water to potable. ... ¶ What this means for someone with a cow is that the cow is then worth about 19L/5gal per day in biodiesel and by pressing for oil a quality fertilizer is produced, that's a lot of fuel to use for heating a room, cooking or a vehicle and when for a village this is a lot of fuel and a lot of water. Getting the water back is a key issue to most living on the edge so for semi-arid to arid areas recycling water should be considered first, before drilling for more and using that money for a one-way ticket to salinated soils. ... ¶ For fields, they need to stop using row agriculture, it doesn't work in a desert very well where contouring for wind and solar gain produce better yields, swaling can turn desert back into steppe, physical changes to leverage natural outcrops and relief, these all are more important than pumping saline water on dry land. ... ¶ It's high-tech to recycle water in volume; however, using algae got easier for wastewater by nano-filtration as a popular size takes viruses out of the water instead of activated charcoal which may not. ... ¶ So, consider that investing in recycling technology needs to have capital for a better long-term solution before drilling or removing river water that have negative effects on groundwater levels on top of also adding salts to the soil as that water evaporates.