Final answer:
The riparian doctrine applies in the water-abundant eastern U.S. and allows adjacent landowners reasonable use of water, while the doctrine of prior appropriation, predominant in the arid western U.S., grants water rights based on first use. Both doctrines are crucial in U.S. water laws for regulating the rights and usage of water resources, considering the geographic and economic implications.
Step-by-step explanation:
The riparian doctrine and the doctrine of prior appropriation are two legal frameworks used to regulate water rights and usage in the United States. The riparian doctrine is typically applied in water-abundant areas, mostly in the eastern states, where it allows landowners who have property along a watercourse to make reasonable use of it as long as the water use does not harm upstream or downstream neighbors.
The doctrine of prior appropriation, on the other hand, originated in the arid western states due to water scarcity and follows a "first in time, first in right" principle, meaning that the first person to use a water resource for a beneficial purpose has the right to use that water to the exclusion of others.
The Newlands Reclamation Act of 1902, spearheaded by Nevada senator Francis Newlands, reflects the doctrine of prior appropriation's influence on policies aimed at distributing water to arid regions in the West for agricultural and commercial development. State governments consider various factors such as physical, chemical, and biological characteristics, geographical setting, and economic considerations when designating appropriate uses for water bodies.
The ongoing issues of water use, spurred by rapid population growth and industrialization, necessitate careful evaluation of the geographic and economic impacts of water-related policies, emphasizing the importance of these doctrines in water law.