In the case of O'Neil v. Northern Colorado Irrigation Company in 1916, the U.S. Supreme Court was tasked with deciding on a dispute over water rights between two parties in Colorado. The plaintiff, O'Neil, claimed that he had senior rights to use water from a certain stream for irrigation purposes based on an agreement made back in 1882. However, the defendant company argued that they held superior rights due to their construction of a canal system prior to this agreement which diverted water from said stream for public use and benefit. The court ruled against O’Neil stating that his claim did not hold up because it was based solely on percolating waters (water flowing underground or through soil), which are generally considered part of the land itself and thus subject to ownership by whoever owns the land above them - unless there is clear evidence proving otherwise. Furthermore, even if these were not percolating waters but instead constituted as definite streams or bodies of surface water under common law principles; still then priority would be given according to appropriation i.e., "first in time is first in right". Since Northern Colorado Irrigation Company's diversion works predated any claims by O’Neil; hence they retained superior usage rights.

The dissenting opinion in the case of O'Neil v. Northern Colorado Irrigation Company argued that the majority's decision to uphold a lower court ruling, which allowed for an irrigation company to divert water from its natural course and use it for agricultural purposes, was incorrect. The dissent emphasized that this action violated existing property rights as well as state laws governing water usage. It further contended that such diversion of water resources could potentially lead to significant environmental damage and disrupt local ecosystems. Moreover, it pointed out potential economic implications by arguing that allowing private entities unrestricted access and control over public resources could result in monopolistic practices detrimental to other stakeholders relying on these same resources.