Groundwater Resource

Groundwater Resource Name: ____________________________________________________ Period: _____ Date: _________ Essential Question: Why do we need to protect our groundwater resource? An aquifer can be compared to a bank account, and ground water occurring in an aquifer is analogous to the money in the account. Hydrologists refer to this type of accounting as a water budget. Ground water can be recharged (deposited) by infiltration from precipitation, surface water, or applied irrigation water; it can be kept in storage (saved); and it can be discharged naturally to streams, springs, or seeps, or transpired by plants (withdrawn). In a ground-water system prior to development, the system is in longterm equilibrium—discharge is equal to recharge, and the volume of water in storage remains relatively constant. Ground-water levels fluctuate in time over a relatively small, natural range. Once pumping begins, however, this equilibrium is changed and ground-water levels decline. Just as a bank account must be balanced, withdrawals from an aquifer by pumping must be balanced by some combination of increased recharge, decreased discharge, and removal from storage (or depletion). An inventory of ground-water levels in wells reflects the volume of water stored (or occurring) in the aquifer, and is analogous to a financial statement. 1. How is an aquifer similar to a bank account? An aquifer is similar to a bank account in that it stores water, much like a bank account stores money. Groundwater occurring ___________________________________________________________________________________________ in an aquifer is analogous to the money in the account. ___________________________________________________________________________________________ 2. How is groundwater recharged? Groundwater is recharged through infiltration from precipitation, surface water, or applied irrigation water. ___________________________________________________________________________________________ ___________________________________________________________________________________________ 3. Where is groundwater naturally discharged? Groundwater is naturally discharged to streams, springs, or seeps, or transpired by plants. ___________________________________________________________________________________________ ___________________________________________________________________________________________ 4. What causes the decline of groundwater supply? The decline of groundwater supply is primarily caused by sustained groundwater pumping. ___________________________________________________________________________________________ 5. Why is there a need to have an inventory of the ground water levels? Think! There is a need to have an inventory of groundwater levels to monitor the volume of water stored in the aquifer, similar to how a financial statement tracks the ___________________________________________________________________________________________ balance of a bank account. This helps in managing and regulating water usage to ensure sustainability. ___________________________________________________________________________________________ The volume of ground water in storage is decreasing in many areas of the United States in response to pumping. Ground-water depletion is primarily caused by sustained ground-water pumping. Some of the negative effects of ground-water depletion include increased pumping costs ( higher water bills), deterioration of water quality( polluted water), reduction of water in streams and lakes, or land subsidence ( sinkhole). Such effects, while variable, happen to some degree with any ground-water use. As with other natural resources, society must weigh the benefits against the consequences of such use. 6. Why is the volume of groundwater decreasing in the United States? Think! The volume of groundwater is decreasing in the United States primarily due to sustained groundwater pumping, leading to groundwater depletion. ___________________________________________________________________________________________ 7. What are the negative effects of water depletion? R. Angat Negative effects of water depletion include increased pumping costs (resulting in higher water bills), deterioration of water ___________________________________________________________________________________________ quality (polluted water), reduction of water in streams and lakes, and land subsidence (sinkholes). ___________________________________________________________________________________________ Seawater intrusions in groundwater Seawater intrusion is the movement of seawater into fresh water aquifers due to natural processes or human activities. Seawater intrusion is caused by decreases in groundwater levels or by rises in seawater levels. When you pump out fresh water rapidly, you lower the height of the freshwater in the aquifer forming a cone of depression. Saltwater from the ocean is making its way into freshwater sources along the coastal plain, causing a myriad of problems. This saltwater intrusion – the landward movement of salinity from the coast onto the coastal plain – has major consequences both to the lives of residents in the area and the economy of eastern N.C. When you have increasing salinity (in freshwater), it leads to several issues: it causes plants to dry and die which is very bad for agriculture and it can decrease water quality by causing soils to release too many nutrients, It is also a big problem for drinking water, which can be extremely expensive to desalinate. 8. What is seawater intrusion? Seawater intrusion is the movement of seawater into freshwater aquifers due to natural processes or human activities. ___________________________________________________________________________________________ ___________________________________________________________________________________________ 9. What causes seawater intrusion? Seawater intrusion is caused by decreases in groundwater levels or by rises in seawater levels. ___________________________________________________________________________________________ ___________________________________________________________________________________________ 10. How are we affected by saltwater intrusion? Saltwater intrusion affects us by causing issues such as drying and death of plants, decreased water quality, which can be ___________________________________________________________________________________________ expensive to desalinate for drinking water, and harm to agriculture and the economy in coastal areas. ___________________________________________________________________________________________ Use of salt for highways deicing is another source of contamination: when this salt washes off roads it may easily move with percolating water into underground aquifers. Salt runoff from highways can make rivers and lakes salty and lead to the death freshwater organisms. High concentrations of chloride can make water unfit for human consumption and for many industrial uses. High concentrations of sodium ion from salts can contribute to certain heart disease or high blood pressure, particularly in susceptible individuals. High concentration of chlorine has bad effects on the environment as well: it can produce leaf burn and even defoliation in sensitive crops; in lakes can increase the presence of metals in waters and prevent the distribution of oxygen and nutrients and thus harm aquatic life. 11. Why do they put salt on highways? Salt is put on highways for deicing purposes to melt snow and ice, making roads safer for travel. ___________________________________________________________________________________________ 12. How are rivers and lakes affected by saltwater runoff? Rivers and lakes are affected by saltwater runoff as it can increase their salinity levels, leading to the death of freshwater organisms and overall ecological imbalances. ___________________________________________________________________________________________ 13. How are we affected by high sodium diet? High sodium diets can contribute to certain health issues such as heart disease or high blood pressure, particularly in susceptible individuals. ___________________________________________________________________________________________ 14. How are plants affected by high chlorine concentration? Plants are affected by high chlorine concentration as it can cause leaf burn and defoliation in sensitive crops. ___________________________________________________________________________________________ A ___15. Which is formed when a section of impermeable rock forces groundwater to move laterally and emerge onto the surface of Earth? A. a spring B. an aquifer C. a geyser D. a well A ___16. The drilling for freshwater increases along a coastal area. What is a likely consequence of this action? A. an intrusion of salt water into aquifers B. the loss of water resources in estuaries C. the destruction of estuaries because of an increase in sea levels D. a decrease in salt concentration in inlet waterways