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21 Mar 2021 
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River Modification
Billington, Jackson, and Melosi (2005) highlight that regional watersheds have always been a valuable resource that has played a part in the development and growth of the United States. Streams, rivers, and lakes are often viewed as economic commodities that continue to support a variety of domestic purposes such as moving goods and people, agrarian activities, manufacturing, and generating power. In his book Beautiful Machine: Rivers of the Republican Plan 1755-1825, John Seelye (1991) argues that the natural meander of a river that has carved its course through the landscape over thousands of years may not initially address the needs of future communities without the manipulation of humans. As the population of a region increased, so too did the demands on natural resources thus forcing state administrations to consider innovated processes that would maximize usage of state river systems.
Seelye posits that America’s water systems became more advantageous when they yielded to humanity’s fundamental needs through the construction of levees, dams, canals and locks that would theoretically improve the efficiency of a river’s natural design. In the late 1800s, many of the streams and rivers in the West were being diverted to manage the irrigation demands from an increase in agrarian activities. It became obvious that during that same period that to accommodate expanding communities, the large river sources that traversed the landscape would require human management to impound the water flow and improve water distribution. As regions began to thrive, the effective use of water sources became an essential component in the evolution of the multiple-purpose river development process. This would drive state administrators to advocate for the construction of large
Costigan and Daniels (2012) point out that the construction of dams to control a river’s water flow has been a part of the landscape for at least the last two millennia and the need to convert the natural channel or store water for agrarian activities was at the forefront of human involvement. As human water needs evolved, the construction of larger, more modern control methods would produce a dramatic change in the magnitude of hydrologic, geomorphologic, and ecological impacts on large rivers (p.90).
Great Plains – Colorado River
The Colorado River is North America’s fifth-largest waterway that drains approximately 240,000 square miles and traverses through seven Western states. The river gets its start from the melting snowpacks of the Rocky Mountains which are channelled into La Poudre Pass Lake located in Colorado’s Rocky Mountain National Park. From the lake, the Colorado River begins a 1450 mile drive to the Gulf of Mexico while draining one of the driest regions in the United States and cutting through some of the United States most scenic landscape such as the Grand Canyon. The first attempts to manage the water supply from the Colorado River began during the mid-1800s when waterways were constructed to divert water for agricultural development within the region. The increasing demands for water eventually led to a frenzy of dam and reservoir construction along the length of the Colorado water system during the fifty years ending around 1970. The impact of water hoarding would dramatically influence the water flow, altering the natural occurrence and ecological dynamics of the river.
Wegner (2008) emphasizes that would be most advantageous for regional administrations to find an effective way to control and manage the natural resource required to accommodate the regions large population of approximately 40 million people. The system management of the Colorado River is a complex proposition and crucial to the survivability of the region, and like many of the large rivers across the United States, any attempt to divert water is often challenged by constraints and stiff opposition as to effectively manage the resource (p.72).
Midwest – Platte River
The North Platte River drains the snowmelt from the eastern Rockies east of the Continental Divide while the South Platte River gets its start from the Mosquito Mountain Range west of South Park across Colorado’s northeastern plains. Each of these tributaries makes its way east to Nebraska where they come together at their confluence at North Platte, Nebraska to form the Platte River before it starts a 300 mile journey to the Missouri River. Eschner, Hadley, and Crowley (1983) propose that there were four general stages to the development of the Platte River beginning around 1891. Because the plains are semiarid to sub-humid the first two stages focused on the construction of small channels and eventually to larger more complex methods in attempts to appropriate the flow and diverted for the irrigation of crops (p.1). The water rights introduced upstream would influence downstream river flow, reducing or altogether eliminate water sources used for regional development. This would eventually push forward the next two stages that prompted the construction of dams and reservoirs to impound water and satisfy the region’s demand for water and power.
Interior West – Arkansas River
The Arkansas River rises in the snow-capped peaks of the Collegiate Range near Leadville, Colorado and becomes one of the major tributaries of the Mississippi River some 1500 miles away. It was Senator John McClellan during the mid-1930s that recognized that flooding would continue to plague Arkansas’ farmland stunting the region’s economic development if measures to control the river were not adopted. Not only did McClellan advocate for improvements to the area’s flood protection capabilities he also recognized the potential of the rivers valuable transportation corridor and hydroelectric source. In 1957 the US Army Corps of Engineers began construction to improve river navigation, flood control and hydroelectric power generation that would support the region’s development.
The McClellan-Kerr Navigational System (MKARNS) consisting of 17 dams and locks (5 in Oklahoma and 12 in Arkansas) has artificially provided better flood control to downstream communities; improved navigation capability of the river; created reservoirs for water supply demands; enhanced fish and wildlife habitats; and generated hydroelectric power for the region. Since its construction, the MKARNS has fulfilled its initial plan as a flood control element that has incorporated hydroelectric plants with the additional benefit of becoming a reliable and vital means to transport commodities. The 450 miles of the river navigable system extends inland to facilitate the exchange of goods in an efficient and cost-effective form of interaction between businesses and manufacturing throughout the region.
Hawaii – Wailuku River
The orographic effect influences the rainfall zones of the Hawaiian Islands and provides the source of headwaters for many streams throughout the islands. The Wailuku River is located on the island of Hawaiʻi and descends from the upper slopes of Mauna Kea, the island highest point as it courses its way about 28 miles towards the northwestern edge of downtown Hilo before draining into Hilo Bay. The region’s perennial water resources are of significant importance to the economic, agricultural activities, and urbanized areas driving the state leadership to identify effective management practices of its surface water resources.
Hawaii’s dam and reservoir initiatives began around the 1900s to address the irrigation needs during the plantation era. Today, the island’s irrigation demands still drive human interaction with the island water sources, but consideration of the island’s need for effective flood control and energy potential of the rivers dominate discussions. In Hilo, some of the water flow from the lower reaches of the Wailuku River is being converted into power from hydro-power stations for the island residents. The Hawaiian Electric Company (HELCO) built its first hydro-power station in 1910 with a second plant pressed into service in 1920. The Wailuku River Hydroelectric Power Company added a third station to the river in 1993 to provide additional power to the island. While the Wailuku River is a small flow river compared to continental US sources and not big enough or suitable for large damming projects to create a more controlled level of power production, it does play an important part in the larger effort for sustainable energy for the island.
North Pacific Coast – Yukon River
The main headwaters of the Yukon River flow from Atlin and Tagish Lakes located in the Northwest corner of British Columbia. From there the river drains to the northwest and continues through to Alaska crossing the state for roughly 1,260 miles before emptying into Kuskokwim Bay off the Bering Sea. The Yukon River is a key transportation corridor that navigates through the ruggedness of the Northern region bringing to the communities within its reach the staples for human survival. Unlike the rivers of the lower 48 states where irrigation dominated, the main focus on the Yukon River during the 1800s was related to the fur trade and the search for mineral wealth. The river has an endured a legacy of environmental issues resulting from decades of unregulated mining practices where the extraction and processing of mineral resources contributed to an increase of risk to water degradation due to contaminants.
There is little consideration given to the development of hydro facilities on the Yukon River even though there is significant potential to generate hydropower. In 1954, the Rampart Dam project was proposed but eventually cancelled due to opposition to the creation of a large reservoir that would threaten villages and traditional land. There are no structures on the United States portion of the river for the generation of hydroelectric power mostly due to the limited demand from a sparse population throughout the region.
California – Sacramento River
The Sacramento River gets its start from the Klamath Mountain range located in northwestern California and flows south for about 450 miles where it meets up with the San Joaquin River before merging into the Sacramento-San Joaquin Delta to drain into the San Francisco Bay and on to the Pacific Ocean. Today, large dams will impound the river to support the heavy demand for irrigation and domestic use for much of Central and Southern California through canals that divert water to agricultural areas and urban centres. Grantham, Figueroa, and Prat (2013) propose that development of California’s water management methods never really followed a central course of action, but rather, reflected the dynamic change in its landscape over the past 150 years (p.456).
The manipulation of the Sacramento River basin began with the beginning of California’s gold rush in the mid-nineteenth century when water was diverted to facilitate hydraulic mining practices. Large dam construction in the region soon followed that not only provided water for mining operations but expanded water resource into agricultural areas. Early water management projects in the region were mostly a result of the individual, corporations, and local administrations, with limited, if any, federal or state intervention. However, early in the 1900s, the demands from a growing population brought about a transformation to water management through the creation of irrigation districts, construction plans, and the development of large supply projects.
Scott and Marquiss (1984) reason that the construction of dams, dikes, levees, drainage works, and protection systems over the last 130 years were initiatives to impound and control water flow to prevent naturally occurring flooding events. To meet statewide demands to secure domestic water, river systems have also been transformed by a complex network of storage and conveyance practices have greatly altered the physical, hydrologic, and ecological character of the Sacramento River (p.52).
Environmental impacts
The humble formation of many rivers in the United States often takes place in a scenic surrounding of relatively undisturbed beginnings. As the water makes flows downstream it begins its integration into civilization and human influence becomes apparent. Scott and Marquiss (1984) argue that the introduction of water control projects may have solved many water demand issues related to regional growth has also created other problems with the hydrological water aquatic environment. The principal activities of humans affecting river systems can fall into four basic themes; an urban settlement in the location of rivers; demands for agricultural development on the floodplain; the hydraulic practice for mining operations; and improving navigation capacities. The impact of these activities on the regime of the river has been and continues to be extreme and far-reaching. Warner and Hendrix (1984) discuss that early levees and ditches were constructed piecemeal by landowners or small groups with very little consideration to the impact on other areas or the meander of the river itself.
Human interference with the hydrological cycle interrupts the river flow regime and its natural drainage capacity. This would result in drainage basins being closed off, causing wetlands to form in places that were once well-drained, changes to vegetative cover, and transformation in land use throughout the drainage basin (p. 55). The growing demands for water resources have forced administrations to develop larger projects which became crucial to supporting the increase in agricultural activities, economic development, and the growth of urban centres. However, the benefits of these projects have routinely come with a cost to the environment. Dam operations and other water projects interfere with the hydrological process that manages the river. Impeding the flow of water slows the progress of water, negatively impacts the river’s habitat structure, and deteriorates water quality conditions.
Most hydroelectric projects consist of a dam structure and a reservoir. Operating these plants may not emit the pollutants into the river such as those from industrial complexes, but a functioning plant can change the water temperature, water chemistry, increase silt build-up, and greatly impede the river’s flow. While hydropower is seen as a clean and renewable source, there are unique environmental concerns associated with the technology; reduced water flow downstream can disrupt habitat; reservoirs often cause upstream flooding; organic material trapped in the supply reservoirs breaks down and releases gases into the water, and blocking the natural flow can interfere with important migration routes for fish. Over time, the actions of humans on the river have had negative implications on the health of river ecosystems.
Conclusion
As the United States moved forward through the 19th century, a consensus emerged on the need to exploit and manipulate water for economic gain. By the latter part of the nineteenth century, it was commonly assumed, even expected, that water should be harnessed and dominated in the name of progress. To meet the challenges and conquer an inhospitable frontier people constructed dams that would impound water either for storage, flood control, water power, or agrarian irrigation. There are obvious patterns in the use of water sources during the development of sites.
First, the diversion of water for irrigation provided the foundation for growth. Second, as communities found a foothold, water was impounded to improve the sites land use and water supply. And, eventually manipulating the river for navigation and power supply. Meybeck (2003) argues that the impact of human activities on the world’s river systems has reached a point in which the waterways can no longer be considered under control solely by the earth’s natural processes (p. 1949). As with any river that experiences an increase in activities whether on the water or its banks there will be the potential to create environmental problems. What we as a dominating species must collaborate on, is finding the necessary balance between managing the resource and maintaining the resource to prevent disruptive consequences to the naturally occurring aquatic ecosystem.