Letter to the editor: If the water level in the Searle River Delta continues to drop, the rising sea level...
GMAT Critical Reasoning : (CR) Questions
Letter to the editor: If the water level in the Searle River Delta continues to drop, the rising sea level will make the water saltier and less suitable for drinking. Currently, 40 percent of the water from upstream tributaries is diverted to neighboring areas. To keep the delta's water level from dropping any further, we should end all current diversions from the upstream tributaries. Neighboring water utilities are likely to see higher costs and diminished water supplies, but these costs are necessary to preserve the delta.
Which of the following would, if true, indicate a serious potential weakness of the suggested plan of action?
Passage Analysis:
| Text from Passage | Analysis |
|---|---|
| If the water level in the Searle River Delta continues to drop, the rising sea level will make the water saltier and less suitable for drinking. |
|
| Currently, 40 percent of the water from upstream tributaries is diverted to neighboring areas. |
|
| To keep the delta's water level from dropping any further, we should end all current diversions from the upstream tributaries. |
|
| Neighboring water utilities are likely to see higher costs and diminished water supplies, but these costs are necessary to preserve the delta. |
|
Argument Flow:
The argument starts by identifying a serious threat (salty water if levels drop), then points to what seems like the obvious cause (water diversions), proposes a direct solution (end all diversions), and finally justifies why the negative consequences are acceptable.
Main Conclusion:
We should end all current water diversions from upstream tributaries to prevent the delta's water level from dropping further.
Logical Structure:
The author uses a simple cause-and-effect logic: diversions cause low water levels, which leads to saltwater intrusion, so stopping diversions should solve the problem. The argument assumes that ending diversions will be sufficient and that no other factors are contributing to the dropping water levels.
Prethinking:
Question type:
Weaken - We need to find information that would reduce our belief in the conclusion that ending all diversions will keep the delta's water level from dropping further
Precision of Claims
The plan's success depends on the precise relationship between diversion amounts (40% of upstream water) and water level maintenance. The claim is specifically about preventing 'any further' drops in water level through ending 'all current diversions'
Strategy
To weaken this plan, we need to find scenarios where even if we stop all diversions (giving the delta 100% instead of 60% of upstream water), the water level would still continue to drop. This could happen if there are other major causes of water loss that aren't addressed by stopping diversions, or if the amount gained from stopping diversions isn't enough to offset other water losses
This doesn't weaken the plan at all. Desalination equipment would be a potential backup solution if the water becomes saltier, but it doesn't address whether the plan of ending diversions will actually work to prevent further water level drops. The plan could still be effective at maintaining water levels, and desalination would just be an additional option. This is irrelevant to the plan's effectiveness.
While this mentions that other factors affect salinity, it doesn't specifically challenge whether ending diversions will prevent further water level drops. The plan is focused on water level, not just salinity. Even if other factors affect salinity, stopping diversions could still successfully maintain water levels, which is the plan's main goal.
The fact that upstream water levels are controlled by dams and reservoirs doesn't necessarily weaken the plan. This is just information about how the water system works. The plan could still be effective regardless of whether dams and reservoirs control upstream levels. We'd need to know more about how these systems would interfere with the plan.
Population growth in neighboring areas doesn't directly challenge whether ending diversions will work to maintain delta water levels. While it might make the consequences of ending diversions more severe for those areas, it doesn't suggest that the plan itself won't achieve its goal of preventing further water level drops in the delta.
This creates a serious weakness because if drought was the primary cause of recent water level drops, and that drought has ended, then water levels should naturally recover without ending the diversions. This suggests the plan is targeting the wrong cause - the author assumes diversions are the main problem, but if drought was the real culprit and it's over, the expensive solution of ending all diversions may be unnecessary. The plan's entire justification becomes questionable.