Question

You have a choice to drill your water well into a shallow, unconfined aquifer or a deeper artesian aquifer. Drilling deeper will cost more money; however, you chose to drill into the artesian aquifer. Why?

Answer 1

Drilling into a deeper artesian aquifer, though more costly, is chosen for its safety regarding pathogen contamination and its pressure that can naturally push water up, possibly reducing pumping costs. Deeper aquifers also help mitigate risks associated with groundwater mining, such as water table decrease and saline intrusion, making them a more sustainable and secure water source.

Step-by-step explanation:

Choice of Drilling into an Artesian Aquifer

Choosing to drill into a deeper artesian aquifer rather than a shallow, unconfined aquifer, despite the higher cost, can be attributed to several advantages. Deep, confined aquifers are generally the safest sources of drinking water with respect to contamination from pathogens. These pathogens often originate from treated or untreated wastewater, which can more readily infect shallow aquifers. Additionally, artesian aquifers are under pressure, which can naturally push water up the well, potentially reducing the need for expensive pumping systems.

Groundwater mining is a significant issue when considering water sources, as the depletion of aquifers can lead to several problems. Overextraction from these water sources can cause a decrease in the water table, leading to more expensive drilling costs for deeper wells. In some cases, the introduction of saline water into fresh groundwater supplies can occur, which is a concern for coastal areas. Choosing an artesian aquifer can mitigate some of these risks as they are often deeper and less susceptible to such impacts.

It is crucial to consider the long-term sustainability and safety of a water supply. With increasing global water demand and issues such as groundwater contamination and depletion, deeper artesian aquifers can provide a more reliable and secure water source, leading to a decision to invest in drilling to these depths despite higher initial costs.

Answer 2

The confined aquifer will contain more water.

Step-by-step explanation:

A shallow aquifer will not have plenty of water, so although you spend less money drilling that aquifer, you will not have water for a long time and will soon have to spend more money to drill another aquifer. On the other hand, a coined aquifer, although it needs more money to be drilled contains more water, being a better option.

Confined aquifers occur when groundwater is confined under a higher pressure than atmospheric pressure, due to the existence of an impermeable confining layer above the aquifer. Because water is at a higher pressure than atmospheric pressure when drilling a hole, water rises to the piezometric surface, giving rise to an artesian hole. Thus water reaches the surface in the form of a draw, and the artesian hole is called a repurring hole.