Nuclear Clean Energy ↔ relates to ↔ Rivers Lakes

niversity comprises ten undergraduate, graduate, and professional schools. It enrolls approximately 12,000 students across its campuses, with 11,000 on the Moscow campus. The university is classified among "R1: Very High Spending and Doctorate Production". Located on the rural Palouse, the university is represented in intercollegiate athletics by the Idaho Vandals, who compete in NCAA Division I, primarily in the Big Sky Conference.

Under the elms Rare Camperdown elms line the walkway between the Music building, Nichols Building (home to Family and Consumer Sciences) and Administration Building. These "upside-down" trees have been on campus for over 80 years and are among few of their kind in the Northwest. The weeping branches and knotty trunk are formed by being grafted upwards. Steam plant Built in 1926, the steam plant provides heat to U of I buildings from a single location. Originally designed to burn coal, then oil, then natural gas, the plant was modified in 1986 to burn waste wood chips left over from local sawmills. The use of wood has significantly reduced the emissions of the plant, as well as cut costs to heat the campus. The plant is shut down twice a year for cleaning and maintenance.

College of Agricultural and Life Sciences (CALS, renamed 2001, formerly Agriculture (1901)) College of Art and Architecture (1981) College of Business and Economics (CBE, 1925) College of Education, Health and Human Sciences (EHH S,1920) College of Engineering (1911) College of Graduate Studies (COGS) College of Law (1909) College of Letters, Arts, and Social Sciences (CLASS, 2002, formed after split of Letters and Science (1900)) College of Natural Resources (CNR, renamed 2000, formerly Forestry, Wildlife, & Range Sciences, originally Forestry (1917)) College of Science (2002, formed after split of Letters and Science, and dissolution of Mines and Earth Resources) School of Health and Medical Professions (SHAMP, 2024) In July 2002, the College of Letters & Science was split into two separate colleges: the College of Science and the College of Letters, Arts, and Social Sciences (CLASS). Concurrently, the College of Mines and Earth Resources was discontinued; its programs were split between the College of Engineering and the new College of Science. The College of Law opened a second campus in Boise in 2010. Initially, the Boise campus only offered third-year classes. It expanded to offer second-year classes in 2014, and as of 2017–18, law students can take their entire three-year curriculum at either location. For the 2024–2025 academic year, the middle 50% of enrolled students scored between 1030 and 1330 on the SAT (with a 50th percentile of 1180), between 510 and 670 on the SAT Evidence-Based Reading and Writing section (50th percentile: 590), and between 520 and 660 on the SAT Math section (50th percentile: 590). Reputation and rankings U.S. News & World Report ranks U of I tied for 89th among the nation's best public universities and tied for 179th among the best national universities in its 2020 report. In 2024, Washington Monthly ranked U of I 83rd among 438 national universities in the U.S. based on U of I's contribution to the public good, as measured by social mobility, research, and promoting public service. In 2025, the Carnegie Classification listed University of Idaho among "R1 Doctoral Universities – Very high research spending and doctorate production", among with other 186 universities. The University of Idaho is included in the 2021 edition of Princeton Review's "Best 386 Colleges." The Princeton Review also ranks U-Idaho as one of the nation's top 286 environmentally responsible colleges. The university was named by the Corporation for National and Community Service to the 2010 President's Higher Education Community Service Honor Roll for exemplary service efforts—more than 3,800 students volunteered more than 150,000 hours to community and service-learning.

power generation. It is currently the U.S.'s largest wholesaler of water, bringing water to more than 31 million people, and providing one in five Western farmers with irrigation water for 10 million acres of farmland, which produce 60% of the nation's vegetables and 25% of its fruits and nuts. The bureau is also the second largest producer of hydroelectric power in the western U.S. On June 17, 1902, in accordance with the Reclamation Act, Secretary of the Interior Ethan Allen Hitchcock established the U.S. Reclamation Service within the U.S. Geological Survey (USGS). The new Reclamation Service studied potential water development projects in each western state with federal lands. Revenue from sale of federal lands was the initial source of the program's funding.

From 1902 to 1907, Reclamation began about 30 projects in Western states. Then, in 1907, the Secretary of the Interior separated the Reclamation Service from the USGS and created an independent bureau within the Department of the Interior. Frederick Haynes Newell was appointed the first director of the new bureau. Beginning with the third person to take over the direction of Reclamation in 1923, David W. Davis, the title was changed from Director to Commissioner. In the early years, many projects encountered problems: lands or soils included in projects were unsuitable for irrigation; land speculation sometimes resulted in poor settlement patterns; proposed repayment schedules could not be met by irrigators who had high land-preparation and facilities-construction costs; settlers were inexperienced in irrigation farming; waterlogging of irrigable lands required expensive drainage projects; and projects were built in areas which could only grow low-value crops. In 1923 the agency was renamed the "Bureau of Reclamation". In 1924, however, in the face of increasing settler unrest and financial woes, the "Fact Finder's Report" spotlighted major problematic issues; the Fact Finders Act in late 1924 sought to resolve some of these problems. In 1928 Congress authorized the Boulder Canyon (Hoover Dam) Project, and large appropriations began, for the first time, to flow to Reclamation from the general funds of the United States. The authorization came only after a hard-fought debate about the pros and cons of public power versus private power. The heyday of Reclamation construction of water facilities occurred during the Depression and the 35 years after World War II. From 1941 to 1947, Civilian Public Service labor was used to carry on projects otherwise interrupted by the war effort. The last major authorization for construction projects occurred in the late 1960s, while a parallel evolution and development of the American environmental movement began to result in strong opposition to water development projects. Even the 1976 failure of Teton Dam as it filled for the first time did not diminish Reclamation's strong international reputation in water development circles. However, this first and only failure of a major Reclamation Bureau dam led to subsequent strengthening of its dam-safety program to avoid similar problems. Even so, the failure of Teton Dam, the environmental movement, and the announcement of President Carter's "hit list" on water projects profoundly affected the direction of Reclamation's programs and activities. Reclamation operates about 180 projects in the 17 western states. The total Reclamation investment for completed project facilities in September 1992 was about $11 billion. Reclamation projects provide agricultural, household, and industrial water to about one‑third of the population of the American West. About 5% of the land area of the West is irrigated, and Reclamation provides water to about one-fifth of that area, some 9,120,000 acres (37,000 km2) in 1992. Reclamation is a major American generator of electricity. As of 2007, Reclamation had 58 power plants on‑line and generated 125,000 GJ of electricity. From 1988 to 1994, Reclamation underwent major reorganization as construction on projects authorized in the 1960s and earlier drew to an end. Reclamation wrote that "The arid West essentially has been reclaimed. The major rivers have been harnessed and facilities are in place or are being completed to meet the most pressing current water demands and those of the immediate future". Emphasis in Reclamation programs shifted from construction to operation and maintenance of existing facilities. Reclamation's redefined official mission is to "manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public".

the nation's vegetables and 25% of its fruits and nuts. The bureau is also the second largest producer of hydroelectric power in the western U.S. On June 17, 1902, in accordance with the Reclamation Act, Secretary of the Interior Ethan Allen Hitchcock established the U.S. Reclamation Service within the U.S. Geological Survey (USGS). The new Reclamation Service studied potential water development projects in each western state with federal lands. Revenue from sale of federal lands was the initial source of the program's funding.

, coined the name "Treasure Valley" in 1959 to reflect the treasure chest of resources and opportunities that the region offered. The valley has a very diverse terrain, from sage flatlands, to mesas, agricultural areas, and urbanized areas. As the Boise Metropolitan Area grows, more and more undeveloped and agricultural land is being urbanized. History Settling the region The tribes that roamed the area, specifically, were the Northern Paiute and Shoshone. In 1834, Thomas McKay built the original Fort Boise, in the area near present-day Parma, which was run for a time by Francois Payette. It later was moved because of flooding troubles and was abandoned in 1854. The Oregon Trail runs through the Treasure Valley. The valley was settled for the most part by ranchers and farmers, initially to supply the gold and silver mining communities in the higher elevations nearby: Idaho City in the Boise Basin and Silver City in the Owyhees. A new Fort Boise was constructed by the U.S. Army in 1863 in present-day Boise, from which the city grew.

ern Oregon to Boise, and is the most populated area in Idaho. Historically, the valley had been known as the Lower Snake River Valley or the Boise River Valley. Pete Olesen, president of the valley's association of local Chambers of Commerce, coined the name "Treasure Valley" in 1959 to reflect the treasure chest of resources and opportunities that the region offered. The valley has a very diverse terrain, from sage flatlands, to mesas, agricultural areas, and urbanized areas.

The Treasure Valley is a valley in the western United States, primarily in southwestern Idaho, where the Payette, Boise, Weiser, Malheur, and Owyhee rivers drain into the Snake River. It includes all the lowland areas from Vale in rural eastern Oregon to Boise, and is the most populated area in Idaho. Historically, the valley had been known as the Lower Snake River Valley or the Boise River Valley. Pete Olesen, president of the valley's association of local Chambers of Commerce, coined the name "Treasure Valley" in 1959 to reflect the treasure chest of resources and opportunities that the region offered. The valley has a very diverse terrain, from sage flatlands, to mesas, agricultural areas, and urbanized areas.

weight of the water to the surrounding valley walls. Dams provide for irrigation, hydropower, water supply, flood management, recreation, inland navigation, and fish farming. Irrigation is a critical application of dams: about 20% of the world's arable land is irrigated using water from reservoirs impounded by dams. Dams generate hydropower, providing a clean and renewable source of electricity, and also supply water for household and industrial needs. An early dam was Jawa Dam in modern Jordan, built around 3000 BCE. The Hittite Empire built several dams in modern Turkey between the 17th and 13th centuries BCE. In the 1st century CE, the Roman Empire began building masonry gravity dams – typically with vertical faces on both upstream and downstream sides. In medieval Europe, dams powered water wheels for milling and mining. The process of designing dams began to transform in the late 18th century from an informal practice to an engineering discipline rooted in science. In the 20th century, the widespread availability of concrete and heavy construction machinery led to the creation of many large-scale dam projects worldwide. The most visible part of a dam is the barrier that retains water, but most dams contain additional structures that perform important functions. When a dam blocks a navigable river, locks may be incorporated into the project to allow ships to pass through. Fish ladders are included in many dams to enable fish to migrate upstream. Spillways are often included to safely release excess reservoir water downstream and prevent catastrophic overflows. Dam outlets allow reservoirs to be partially drained to purge sediment, perform maintenance, or increase water flow downstream. A dam may be deliberately removed for various reasons: if it poses a safety hazard, if the dam no longer fulfills its original purpose, to restore fish migration routes, or to improve the health of downstream rivers by improving sediment flow. Dams occasionally fail, resulting in flooding and loss of life.

The main purposes that dams serve include irrigation, hydropower, water supply, flood management, recreation, inland navigation, and fish farming. Many dams – called "multi-purpose dams" – support two or more primary functions. Irrigation is a critical application of dams: about 20% of the world's arable land is irrigated by water that originated in reservoirs impounded by dams (as of 2022). In addition to directly moving water from the reservoir to irrigation canals, dams can also support irrigation by "dry-season releases": the dam impounds water during the wet season, and releases it downstream during the dry season, thus ensuring water in the river year-round. Hydropower provides clean, renewable energy in the form of hydroelectricity. As of 2024, global hydropower capacity accounted for about 14% of the world's electricity supply. More than 80% of the world's total reservoir water storage capacity is used for hydropower, as of 2006. The world's 40 largest reservoirs store 40% of the world's reservoir water, of which 90% is devoted to hydropower, as of 2006. In some climates, hydropower dams can act as an annual buffering system: the reservoir can be filled during the rainy season, then during the dry season (when it is typically hotter and electricity is needed to run air conditioning systems) the water can be released to generate electricity. Some hydropower dams provide a pumped-storage capability: these dams consume excess electricity (for example, from solar power on a sunny day) to drive pumps that lift water from a low reservoir to a higher reservoir. When the electrical grid needs more power (for example, on a cloudy day), the water can be released to power the dam's generators to create hydroelectricity. A pumped-storage capability can be used in a 24-hour cycle: during the night, when community use of electricity is low, conventional power sources (nuclear, oil) can power pumps to lift water into reservoirs; then – during the peak consumption hours in daytime – the water can be released through the dam's generators to generate electricity. Water supply – for domestic and industrial use – is the third most common purpose of large dams. In 2025, 3,394 large dams were dedicated to this use. Industrial usage is about twice domestic usage, but some of the water withdrawn from reservoirs (such as water used solely for cooling purposes) is returned to the river system. Flood management is an important function of many dams. In 2025, there were 2,510 large dams in the world devoted to flood management. These dams do not try to prevent all floodwaters from reaching downstream. Instead, they try to reduce the peak flood level (height) to a safe limit. Since floods are so unpredictable, these goals are typically expressed as statistical margins based on lengthy return periods. For example, a dam may be designed with the goal of safely regulating 1-in-100 year floods. The flood-control benefits of dams may become increasingly important in the 21st century as flood risks are projected to increase due to climate change. Many dams are built on rivers for the purpose of keeping the water level sufficiently high to support transportation, including barges that carry freight. These dams are typically low, and are found near industries that require cargo to be transported on waterways.

ing and mining. The process of designing dams began to transform in the late 18th century from an informal practice to an engineering discipline rooted in science. In the 20th century, the widespread availability of concrete and heavy construction machinery led to the creation of many large-scale dam projects worldwide. The most visible part of a dam is the barrier that retains water, but most dams contain additional structures that perform important functions. When a dam blocks a navigable river, locks may be incorporated into the project to allow ships to pass through. Fish ladders are included in many dams to enable fish to migrate upstream. Spillways are often included to safely release excess reservoir water downstream and prevent catastrophic overflows. Dam outlets allow reservoirs to be partially drained to purge sediment, perform maintenance, or increase water flow downstream. A dam may be deliberately removed for various reasons: if it poses a safety hazard, if the dam no longer fulfills its original purpose, to restore fish migration routes, or to improve the health of downstream rivers by improving sediment flow. Dams occasionally fail, resulting in flooding and loss of life.

to the head of the North Fork Payette River being 180 miles (290 km), while to the head of the South Fork the cumulative length is nearly 163 miles (262 km). The combined Payette River flows into an agricultural valley and empties into the Snake River near the city of Payette at an elevation of 2,125 feet (648 m). The Payette River's drainage basin comprises about 3,240 square miles (8,400 km2). It is a physiographic section of the Columbia Plateau province, which in turn is part of the larger Intermontane Plateaus physiographic division.

The river's watershed was originally settled by the Shoshone, Nez Perce, Paiute and Bannock Native American groups. Before contact with Europeans, many of the indigenous peoples had no permanent villages or settlements. During the fall and winter, they camped in the semi-arid lower valley of the main stem Payette River. In spring and summer, they temporarily moved to the lush area of lakes and wetlands along the North Fork now known as Long Valley, where they hunted and gathered in preparation for the coming winter. Camas bulbs, widespread in this area, was a staple of their diet. In order to maintain the naturally occurring fields of camas, they would set controlled burns whenever they moved to the next camp. The seasonal burning also cleared unwanted vegetation and protected their campsites from overgrowth. In the early 19th century, Europeans began exploring western Idaho. Francois Payette, for whom the river is named, was a French-Canadian fur trapper who worked for the North West Company and was one of the first people of European descent to explore the Payette River basin. Payette ventured east from Fort Astoria in 1818. From 1835 to 1844, he headed the Hudson's Bay Company's Fort Boise trading post near Parma, on the Snake River some distance south of the Payette River. In 1844, Payette retired to Montreal, still over twenty years before settlers began to arrive in great numbers from the eastern United States. One of the first pioneer settlements was on Clear Creek, a tributary of the South Fork Payette River. Many of the Native Americans were unhappy with the new settlers for taking and causing damage to their lands, especially due to mining, logging, and grazing. Armed conflicts resulted, including the Nez Perce War of 1877, when the US Army was dispatched to western Idaho. Due to the abundant timber in the Payette River basin, one of the first new industries in the 19th century was logging, but did not reach large scale until the early 20th century. Demand for wooden railroad ties for the Oregon Short Line (OSL) in the 1880s increased logging operations in the area. One of the main centers of logging was in the southern part of Long Valley downstream from what is now the town of Cascade. A splash dam was built in 1902 by the Minnesota-based Payette Lumber and Manufacturing Company on the North Fork in order to help the transportation of logs downstream. Settlers began to move into the upper Payette basin, and in 1911, the Idaho Northern Railroad was constructed between Emmett along the Payette River, through Black Canyon and the North Fork, and ending just below Long Valley at Smith's Ferry on the river, named for a settler who bought the operation in 1891. The railroad transported timber, livestock and crops between Long Valley and the Treasure Valley. Starting around 1874, there was heavy agricultural development in the valley of the lower Payette River. Irrigation systems were necessary due to the semi-arid climate of this area. The Last Chance Canal and Nobel Canal were among the first private ditches constructed to divert water from the Payette River. The U.S. Bureau of Reclamation (USBR) constructed Black Canyon Diversion Dam in 1924 to direct water from the Payette River into the Emmett and Black Canyon Canals, which run at higher elevations than the older ditches and vastly increased the potential for irrigation. In order to store water for irrigation in the dry season, the USBR constructed Deadwood Dam in 1929 on the Deadwood River tributary of the South Fork. Cascade Dam was constructed in 1948, flooding a large area of Long Valley.

es (262 km). The combined Payette River flows into an agricultural valley and empties into the Snake River near the city of Payette at an elevation of 2,125 feet (648 m). The Payette River's drainage basin comprises about 3,240 square miles (8,400 km2). It is a physiographic section of the Columbia Plateau province, which in turn is part of the larger Intermontane Plateaus physiographic division.

and four navigation dams on its lower section created a shipping channel to Lewiston, Idaho – the furthest inland seaport on the West Coast. While dam construction, commercial fishing and other human activities have greatly reduced anadromous fish populations since the late 19th century, the Snake River watershed is still considered important habitat for these fish. The Snake and its tributary, the Salmon River, host the longest sockeye salmon run in the world, stretching 900 miles (1,400 km) from the Pacific to Redfish Lake in Idaho. Since the 1950s, public agencies, tribal governments and private utilities have invested heavily in fishery restoration and hatchery programs, with limited success.

s of Idaho, Oregon and Washington, and finally the rolling Palouse Hills of southeast Washington. It joins the Columbia River just downstream from the Tri-Cities, Washington, in the southern Columbia Basin. The river's watershed, which drains parts of six U.S. states, is situated between the Rocky Mountains to the north and east, the Great Basin to the south, and the Blue Mountains and Oregon high desert to the west. The region has a long history of volcanism; millions of years ago, Columbia River basalts covered vast areas of the western Snake River watershed, while the Snake River Plain was a product of the Yellowstone volcanic hotspot. The river was further altered by catastrophic flooding in the most recent Ice Age, which created such features as the Snake River Canyon and Shoshone Falls. The Snake River once hosted some of the largest North American runs of salmon and other anadromous fish. For thousands of years, salmon fishing has played a central role in the culture and diet of indigenous peoples. The Shoshone and Nez Perce were the largest of several tribes that lived along the river by the turn of the 19th century. In 1805, while searching for a route from the eastern US to the Pacific, Lewis and Clark became the first non-natives to see the river. Fur trappers explored more of the watershed, and drove beaver to near extinction as the Americans and British vied for control of Oregon Territory. Although travelers on the Oregon Trail initially shunned the dry and rocky Snake River region, a flood of settlers followed gold discoveries in the 1860s, leading to decades of military conflict and the eventual expulsion of tribes to reservations. At the turn of the 20th century, some of the first large irrigation projects in the western US were developed along the Snake River. South-central Idaho earned the nickname "Magic Valley" with the rapid transformation of desert into farmland. Numerous hydroelectric dams were also constructed, and four navigation dams on its lower section created a shipping channel to Lewiston, Idaho – the furthest inland seaport on the West Coast. While dam construction, commercial fishing and other human activities have greatly reduced anadromous fish populations since the late 19th century, the Snake River watershed is still considered important habitat for these fish. The Snake and its tributary, the Salmon River, host the longest sockeye salmon run in the world, stretching 900 miles (1,400 km) from the Pacific to Redfish Lake in Idaho. Since the 1950s, public agencies, tribal governments and private utilities have invested heavily in fishery restoration and hatchery programs, with limited success.

The 107,500-square-mile (278,000 km2) Snake River watershed drains about 87 percent of the state of Idaho, 18 percent of Washington and 17 percent of Oregon, in addition to small portions of Wyoming, Utah and Nevada. From the Lost Trail Pass north of Salmon, Idaho to Tri-Basin Divide south of Afton, Wyoming, the eastern edge of the Snake River watershed follows the Continental Divide. As the Continental Divide also forms the Idaho–Montana border south of Lost Trail Pass, the Snake watershed touches Montana for a long distance, but does not extend into it. The Snake drains by far the largest area of any Columbia River tributary, making up about 40 percent of the entire Columbia River watershed. Compared with the Columbia above their confluence, the Snake River is about 180 miles (290 km) longer and drains a similarly sized area, though the Columbia carries more than twice the volume of water. The Snake River watershed is very mountainous, with the northern two-thirds of it occupied by vast mountain ranges of the Rockies, primarily the Salmon River Mountains of central Idaho and the Bitterroot Range along the Idaho–Montana border. The Blue Mountains form much of the western boundary of the Snake watershed from southeast Washington down into Oregon. To the south are numerous small isolated mountain ranges of the Basin and Range Province, such as the Independence and Albion Mountains. To the east are more ranges of the Rockies including the Tetons and the Wind River Range; the latter includes Gannett Peak, the highest point in the Snake River basin at 13,816 feet (4,211 m). Surface volcanic features – such as lava fields, cones, and thermal springs – are replete in the southern part of the Snake watershed, from Craters of the Moon National Monument northeast of Twin Falls to the Yellowstone caldera, while ancient lava flows of the Columbia River basalts underlie the western part of the watershed. The Snake River Plain is the largest area without mountains, but it still features rugged terrain, being crisscrossed by canyons formed by the Snake River and its tributaries. Due to the rain shadow effect of the Cascades, precipitation as a whole is scant, averaging 14 inches (360 mm) across the entire watershed. Most precipitation falls at higher elevations as snow, thus, most runoff in the Snake River watershed derives from snowmelt. Jackson Hole, Wyoming experiences an alpine climate with an average of 30 in (760 mm) of rain and 252 in (6,400 mm) of snow. The coldest month is January, with a mean temperature of 13 °F (−11 °C), and the hottest is July at 57.7 °F (14.3 °C). Twin Falls experiences a semi-arid climate, with about 9 in (230 mm) of rain and 13 in (330 mm) of snow. Monthly mean temperatures range from 29.4 °F (−1.4 °C) in January to 73.1 °F (22.8 °C) in July. The Columbia Basin around the river's mouth also has a semi-arid climate, with about 10 in (250 mm) of rain and 5 in (130 mm) of snow as measured at Ice Harbor Dam.

tion of a hydroelectric complex can have significant environmental impact, principally in loss of arable land and population displacement. They also disrupt the natural ecology of the river involved, affecting habitats and ecosystems, and siltation and erosion patterns. While dams can ameliorate the risks of flooding, dam failure can be catastrophic. In 2021, global installed hydropower electrical capacity reached almost 1,400 GW, the highest among all renewable energy technologies. Hydroelectricity plays a leading role in countries like Brazil, Norway and China. but there are geographical limits and environmental issues. Tidal power can be used in coastal regions. China added 24 GW in 2022, accounting for nearly three-quarters of global hydropower capacity additions. Europe added 2 GW, the largest amount for the region since 1990.

n and erosion patterns. While dams can ameliorate the risks of flooding, dam failure can be catastrophic. In 2021, global installed hydropower electrical capacity reached almost 1,400 GW, the highest among all renewable energy technologies. Hydroelectricity plays a leading role in countries like Brazil, Norway and China. but there are geographical limits and environmental issues. Tidal power can be used in coastal regions. China added 24 GW in 2022, accounting for nearly three-quarters of global hydropower capacity additions. Europe added 2 GW, the largest amount for the region since 1990.

ffecting habitats and ecosystems, and siltation and erosion patterns. While dams can ameliorate the risks of flooding, dam failure can be catastrophic. In 2021, global installed hydropower electrical capacity reached almost 1,400 GW, the highest among all renewable energy technologies. Hydroelectricity plays a leading role in countries like Brazil, Norway and China. but there are geographical limits and environmental issues. Tidal power can be used in coastal regions. China added 24 GW in 2022, accounting for nearly three-quarters of global hydropower capacity additions. Europe added 2 GW, the largest amount for the region since 1990.

, Arts & Sciences, and Education; MPA program in the School of Public Service; and the MPH program in the College of Health Sciences. It is classified among "R2: Doctoral Universities – High research activity".

The university also has an honors college. Within the College of Arts and Sciences is the School of the Environment, approved by the Idaho State Board of Education in 2022 and established in 2023. Boise State's fall enrollment in 2016 was 23,886 students, and approximately 76 percent of these students were Idaho residents. More than 90 percent of Boise State's first-year students come directly from high school. In the 2015–16 school year, Boise State awarded diplomas to 3,916 distinct graduates, including 18 doctorates, 10 education specialists, 670 master's and 2,998 bachelor's degrees. The university is classified among "R2: Doctoral Universities – High research spending and doctorate production".

Boise State University (BSU) is a public research university in Boise, Idaho, United States. Founded in 1932 by the Episcopal Church, it became an independent junior college in 1934 and has been awarding baccalaureate and master's degrees since 1965. It became a public institution in 1969. Boise State offers more than 100 graduate programs, including a variety of MBA programs and the MAcc program in the College of Business and Economics; master's and PhD programs in the Colleges of Engineering, Arts & Sciences, and Education; MPA program in the School of Public Service; and the MPH program in the College of Health Sciences. It is classified among "R2: Doctoral Universities – High research activity".

The Clean Water Act (CWA) is the primary federal law in the United States governing water pollution. Its objective is to restore and maintain the chemical, physical, and biological integrity of the nation's waters; recognizing the primary responsibilities of the states in addressing pollution and providing assistance to states to do so, including funding for publicly owned treatment works for the improvement of wastewater treatment; and maintaining the integrity of wetlands. The Clean Water Act was one of the first and most influential modern environmental laws in the United States. Its laws and regulations are primarily administered by the U.S. Environmental Protection Agency (EPA) in coordination with state governments, though some of its provisions, such as those involving filling or dredging, are administered by the U.S. Army Corps of Engineers. Its implementing regulations are codified at 40 C.F.R. Subchapters D, N, and O (Parts 100–140, 401–471, and 501–503). Technically, the name of the law is the Federal Water Pollution Control Act. The first FWPCA was enacted in 1948, but took on its modern form when completely rewritten in 1972 in an act entitled the Federal Water Pollution Control Act Amendments of 1972. Major changes have subsequently been introduced via amendatory legislation including the Clean Water Act of 1977 and the Water Quality Act (WQA) of 1987. The Clean Water Act does not directly address groundwater contamination.

d providing assistance to states to do so, including funding for publicly owned treatment works for the improvement of wastewater treatment; and maintaining the integrity of wetlands. The Clean Water Act was one of the first and most influential modern environmental laws in the United States. Its laws and regulations are primarily administered by the U.S. Environmental Protection Agency (EPA) in coordination with state governments, though some of its provisions, such as those involving filling or dredging, are administered by the U.S. Army Corps of Engineers. Its implementing regulations are codified at 40 C.F.R. Subchapters D, N, and O (Parts 100–140, 401–471, and 501–503). Technically, the name of the law is the Federal Water Pollution Control Act. The first FWPCA was enacted in 1948, but took on its modern form when completely rewritten in 1972 in an act entitled the Federal Water Pollution Control Act Amendments of 1972. Major changes have subsequently been introduced via amendatory legislation including the Clean Water Act of 1977 and the Water Quality Act (WQA) of 1987. The Clean Water Act does not directly address groundwater contamination.

ngineers. Its implementing regulations are codified at 40 C.F.R. Subchapters D, N, and O (Parts 100–140, 401–471, and 501–503). Technically, the name of the law is the Federal Water Pollution Control Act. The first FWPCA was enacted in 1948, but took on its modern form when completely rewritten in 1972 in an act entitled the Federal Water Pollution Control Act Amendments of 1972. Major changes have subsequently been introduced via amendatory legislation including the Clean Water Act of 1977 and the Water Quality Act (WQA) of 1987. The Clean Water Act does not directly address groundwater contamination.

r high latitude. Snowpacks are an important water resource that feed streams and rivers as they melt, sometimes leading to flooding. Snowpacks provide water to down-slope communities for drinking and agriculture. High-latitude or high-elevation snowpacks contribute mass to glaciers in their accumulation zones, where annual snow deposition exceeds annual melting. Assessing the formation and stability of snowpacks is important in the study and prediction of avalanches. Scientists study the physical properties of snow under different conditions and their evolution, and more specifically snow metamorphism, snow hydrology (the contribution of snow melt to catchment hydrology), the evolution of snow cover with climate change and its effect on the ice–albedo feedback and hydrology, both on the ground and by using remote sensing. Snow is also studied in a more global context of impact on animal habitats and plant succession.

g to flooding. Snowpacks provide water to down-slope communities for drinking and agriculture. High-latitude or high-elevation snowpacks contribute mass to glaciers in their accumulation zones, where annual snow deposition exceeds annual melting. Assessing the formation and stability of snowpacks is important in the study and prediction of avalanches. Scientists study the physical properties of snow under different conditions and their evolution, and more specifically snow metamorphism, snow hydrology (the contribution of snow melt to catchment hydrology), the evolution of snow cover with climate change and its effect on the ice–albedo feedback and hydrology, both on the ground and by using remote sensing. Snow is also studied in a more global context of impact on animal habitats and plant succession.

The three main types of snowpack are maritime, intermountain, and continental. Maritime snowpacks are typically found on the windward side of continents, near oceans. They usually feature warmer winter temperatures that stay around freezing (−5 to 5 °C (20 to 40 °F)) and more precipitation, leading to a snowpack that is over 3 metres (10 ft) deep. Frequent storms deposit snow with a higher snow-water equivalent, often around 10 to 20 percent moisture. Most avalanches occur during or immediately after storms, as weak layers do not persist with warmer temperatures and frequent midwinter rain. Thus, it is typical to ski steep, avalanche prone terrain as soon as 24 to 36 hours after the storm. Many areas with a maritime snowpack receive 15 to 25 metres (49 to 82 ft) of annual snowfall. Areas with a typically maritime snowpack include the Cascade Range, Coastal Range, western Norway, and the Sierra Nevada. Intermountain or transitional snowpack is colder and drier than maritime snowpack, usually around 1.5 to 3 metres (5 to 10 ft) deep. Temperatures stay colder than maritime climates but warmer than continental climates, around −15 to 3 °C (5 to 40 °F). Although intermountain snowpacks can feature persistent weak layers, avalanches also occur within storm snow. Unlike in maritime climates, instability lingers for several days to weeks after storms. Typical areas for this snowpack include the Wasatch Range, Selkirks, and parts of the Alps. Continental snowpacks are the coldest and thinnest, featuring snow less than 1.5 metres (5 ft) deep and winter temperatures under −10 °C (10 °F). Storms are less frequent and deposit less snow, which is less dense. Faceted snow and depth hoar is the typical weak layer, often covered by hard wind slabs. The instability is very persistent and often leads to higher rates of avalanche fatalities. Areas with a typically continental snowpack include Colorado, the Canadian Rockies, the Brooks Range, and the Pamir Mountains. Because of the persistence of weak layers, forecasting relies much more heavily on snowpit tests to determine stability. In continental climates, avalanches can start on less steep slopes than in intermountain or maritime climates. Local and regional weather conditions can change the type of snowpack typical for a region, for example a typically maritime region might have a cold and thin early season snowpack that resembles continental type, while even a few feet apart the snowpack depth can vary enough to produce vastly different conditions.

Surface irrigation, also known as gravity irrigation, is the oldest form of irrigation and has been in use for thousands of years. In surface (furrow, flood, or level basin) irrigation systems, water moves across the surface of agricultural lands to wet it and infiltrate into the soil. Water moves by following gravity or the slope of the land. Surface irrigation can be subdivided into furrow, border strip, or basin irrigation. It is often called flood irrigation when irrigation results in flooding or near-flooding of the cultivated land. Historically, surface irrigation has been the most common method for irrigating agricultural land in most parts of the world. The water application efficiency of surface irrigation is typically lower than that of other irrigation methods, due in part to limited control over applied depths. Surface irrigation involves significantly lower capital costs and energy requirements than pressurized irrigation systems. Hence, it is often the irrigation choice for developing nations, for low-value crops, and for large fields. Where water levels from the irrigation source permit, they are controlled by dikes (levees), usually plugged with soil. This is often seen in terraced rice fields (rice paddies), where the method is used to flood or control water levels in each distinct field.

Field Water Efficiency (%) = (Water Transpired by Crop ÷ Water Applied to Field) x 100 Increased irrigation efficiency has several positive outcomes for the farmer, the community, and the wider environment. Low application efficiency indicates that the amount of water applied to the field exceeds the crop or field requirements. Increasing the application efficiency means that the amount of crop produced per unit of water increases. Improved efficiency may be achieved by applying less water to an existing field or by using water more wisely, thereby achieving higher yields in the same area of land. In some parts of the world, farmers are charged for irrigation water; hence, over-application has a direct financial cost to the farmer. Irrigation often requires pumping energy (electricity or fossil fuels) to deliver water to the field or to supply the required operating pressure. Hence, increased efficiency will reduce both water and energy costs per unit of agricultural production. A reduction in water use on one field may allow the farmer to irrigate a larger area of land, increasing total agricultural production. Low efficiency usually means that excess water is lost through seepage or runoff, both of which can result in loss of crop nutrients or pesticides with potential adverse impacts on the surrounding environment. Improving the efficiency of irrigation is usually achieved in one of two ways: either by improving the system design or by optimizing the irrigation management. Improving system design includes converting from one form of irrigation to another (e.g., from furrow to drip irrigation) and making small changes to the current system (e.g., adjusting flow rates and operating pressures).

Archaeological investigations have found evidence of irrigation in areas lacking sufficient natural rainfall to support rainfed agriculture. Some of the earliest known use of the technology dates to the 6th millennium BCE in Khuzistan in the south-west of Iran. The site of Choga Mami, in present-day Iraq on the border with Iran, is believed to be the earliest to show the first canal irrigation in operation at about 6000 BCE. Irrigation was used to manipulate water in the alluvial plains of the Indus Valley Civilization, with its application estimated to have begun around 4500 BCE and to have drastically increased the size and prosperity of their agricultural settlements. The Indus Valley Civilization developed sophisticated irrigation and water-storage systems, including artificial reservoirs at Girnar dated to 3000 BCE, and an early canal irrigation system from c. 2600 BCE. Large-scale agriculture was practiced, with an extensive network of canals used for irrigation. Farmers in the Mesopotamian plain used irrigation from at least the third millennium BCE. They developed perennial irrigation, regularly watering crops throughout the growing season by coaxing water through a matrix of small channels formed in the field. Ancient Egyptians practiced basin irrigation using the flooding of the Nile to inundate land plots which had been surrounded by dikes. The flood water remained until the fertile sediment had settled before the engineers returned the surplus to the watercourse. There is evidence of the ancient Egyptian pharaoh Amenemhet III in the twelfth dynasty (about 1800 BCE) using the natural lake of the Faiyum Oasis as a reservoir to store surpluses of water for use during dry seasons.

A reservoir (; from French réservoir [ʁezɛʁvwaʁ]) is an enlarged lake behind a dam, usually built to store fresh water, often doubling for hydroelectric power generation. Reservoirs are created by controlling a watercourse that drains an existing body of water, interrupting a watercourse to form an embayment within it, excavating, or building any number of retaining walls or levees to enclose any area to store water.

Downstream water supply water may be released from an upland reservoir so that it can be abstracted for drinking water lower down the system, sometimes hundreds of miles further downstream. Irrigation water in an irrigation reservoir may be released into networks of canals for use in farmlands or secondary water systems. Irrigation may also be supported by reservoirs which maintain river flows, allowing water to be abstracted for irrigation lower down the river. Flood control also known as an "attenuation" or "balancing" reservoirs, flood control reservoirs collect water at times of very high rainfall, then release it slowly during the following weeks or months. Some of these reservoirs are constructed across the river line, with the onward flow controlled by an orifice plate. When river flow exceeds the capacity of the orifice plate, water builds up behind the dam; but as soon as the flow rate reduces, the water behind the dam is slowly released until the reservoir is empty again. In some cases, such reservoirs only function a few times in a decade, and the land behind the reservoir may be developed as community or recreational land. A new generation of balancing dams are being developed to combat the possible consequences of climate change. They are called "Flood Detention Reservoirs". Because these reservoirs will remain dry for long periods, there may be a risk of the clay core drying out, reducing its structural stability. Recent developments include the use of composite core fill made from recycled materials as an alternative to clay. Canals Where a natural watercourse's water is not available to be diverted into a canal, a reservoir may be built to guarantee the water level in the canal: for example, where a canal climbs through locks to cross a range of hills. Another use is to reduce costs or construction time when the canal must be dug through rock, as used on the Rideau Canal with The Narrows locks dividing the two Rideau's and essentially turning the upper Rideau into an enlarged reservoir, albeit only by two or three feet. Recreation water may be released from a reservoir to create or supplement white water conditions for kayaking and other white-water sports.

Hydroelectricity and climate change Depending upon the area flooded versus power produced, a reservoir built for hydro-electricity generation can either reduce or increase the net production of greenhouse gases when compared to other sources of power. A study for the National Institute for Research in the Amazon found that hydroelectric reservoirs release a large pulse of carbon dioxide from decay of trees left standing in the reservoirs, especially during the first decade after flooding. This elevates the global warming impact of the dams to levels much higher than would occur by generating the same power from fossil fuels. According to the World Commission on Dams report (Dams And Development), when the reservoir is relatively large and no prior clearing of forest in the flooded area was undertaken, greenhouse gas emissions from the reservoir could be higher than those of a conventional oil-fired thermal generation plant. For instance, In 1990, the impoundment behind the Balbina Dam in Brazil (inaugurated in 1987) had over 20 times the impact on global warming than would generating the same power from fossil fuels, due to the large area flooded per unit of electricity generated. Another study published in the Global Biogeochemical Cycles also found that newly flooded reservoirs released more carbon dioxide and methane than the pre-flooded landscape, noting that forest lands, wetlands, and preexisting water features all released differing amounts of carbon dioxide and methane both pre- and post-flooding. The Tucuruí Dam in Brazil (completed in 1984) had only 0.4 times the impact on global warming than would generating the same power from fossil fuels. A two-year study of carbon dioxide and methane releases in Canada concluded that while the hydroelectric reservoirs there do emit greenhouse gases, it is on a much smaller scale than thermal power plants of similar capacity.

rid areas where irrigation is practiced, such systems are often the source of conflict, both legal and physical. Some systems treat surface water and ground water in the same manner, while others use different principles for each. Types Water rights requires consideration of the context and origin of the right being discussed, or asserted. Traditionally, water rights refers to the utilization of water as an element supporting basic human needs like drinking or irrigation. Water rights could also include the physical occupancy of waterways for purposes of travel, commerce and recreational pursuits. The legal principles and doctrines that form the basis of each type of water rights are not interchangeable and vary according to local and national laws.

In water law, water right is the right of a user to use water from a water source, e.g., a river, stream, pond or source of groundwater. In areas with plentiful water and few users, such systems are generally not complicated or contentious. In other areas, especially arid areas where irrigation is practiced, such systems are often the source of conflict, both legal and physical.

Community-based allocation of water In some jurisdictions, appropriative water rights can be granted directly to communities. Here, water is reserved to provide sufficient capacity for the future growth of that particular community. For example, California provides communities and other water users within watersheds senior status over appropriative (use-based) water rights solely because they are located where the water originates and naturally flows. A second example of community-based water rights is pueblo water rights. As recognized by California, pueblo water rights are grants to individual settlements (i.e. pueblos) over all streams and rivers flowing through the city and to all groundwater aquifers underlying that particular city. The pueblo's claim expands with the needs of the city and may be used to supply the needs of areas that are later annexed to the city. While California recognizes pueblo water rights, pueblo water rights are controversial.

tment of Environmental Quality is the department of the Idaho state government responsible for administering state and federal environmental laws and regulations. The department's main offices are in Boise, and six regional offices are also maintained. History The department was established in 2000 upon the passing of amendments to the Idaho Environmental Protection and Health Act.

also maintained. History The department was established in 2000 upon the passing of amendments to the Idaho Environmental Protection and Health Act. Before 2000, DEQ in Idaho was a division of the Department of Health and Welfare. Structure and functions It is organized into five divisions: Air Quality: responsible for monitoring air pollution and permits relating to the same Water Quality: sets water quality standards and monitors ground, surface, and drinking water quality Waste Management and Remediation: responsible for all issues relating to waste disposal Environmental Management and Information: provides technical communications services, including publications Technical Services: the research and technical enforcement division, including inspection activities The department also exercises non-regulatory oversight of the Idaho National Laboratory. The director of the department reports to the governor.

Air Quality: responsible for monitoring air pollution and permits relating to the same Water Quality: sets water quality standards and monitors ground, surface, and drinking water quality Waste Management and Remediation: responsible for all issues relating to waste disposal Environmental Management and Information: provides technical communications services, including publications Technical Services: the research and technical enforcement division, including inspection activities The department also exercises non-regulatory oversight of the Idaho National Laboratory. The director of the department reports to the governor.

ise, as well as part of the western Snake River Plain. The watershed encompasses approximately 4,100 square miles (11,000 km2) of highly diverse habitats, including alpine canyons, forest, rangeland, agricultural lands, and urban areas. Description The Boise River rises in three separate forks in the Sawtooth Range at elevations exceeding 10,000 feet (3,050 m), and is formed by the confluence of its North and Middle forks. The North Fork, 50 miles (80 km) long, rises in the Sawtooth Wilderness Area, along the Boise–Elmore county line, 60 miles (100 km) northeast of Boise. It flows generally southwest through the remote mountains in the Boise National Forest. The Middle Fork, approximately 52 miles (84 km) in length, rises within 12 miles (19 km) of the North Fork in the southern Sawtooth Wilderness Area in northeastern Elmore County. It flows west-southwest near the town of Atlanta, joining the North Fork to form the Boise River, approximately 15 miles (24 km) southeast of Idaho City.

History The river was called "Reed's River" in the early 19th century, named after Pacific Fur Company employee John Reed, who explored parts of the river throughout 1813 and 1814. The river is diverted to canals for irrigation on the plain west of what is now Boise. The dams that form the mountain reservoirs were constructed as part of the Bureau of Reclamation's "Boise Project" to provide agricultural irrigation, hydroelectricity, drinking water, and flood control to Boise and the Treasure Valley. The major projects' initial completion dates were: 1909 – Boise River Diversion Dam & New York Canal 1915 – Arrowrock Dam 1950 – Anderson Ranch Dam - (S. Fork) 1955 – Lucky Peak Dam - (U.S. Army Corps of Engineers) The Boise River was proposed for 50 years for a dam at Twin Springs, culminating in a 1966 Project Travois proposal, which would have used nuclear explosives to either create large amounts of rockfill aggregate for dam construction, or to induce a landslide that would have much the same effect. Project Travois was a component of Project Plowshare.

Recreation The river is a popular destination for floating, specifically on the Boise greenbelt. Tubers and floaters launch at Barber Park and land at Ann Morrison Park, between major irrigation diversion dams. Several minor diversion weirs are passed as well as several bridges on the 6-mile (10 km) trip. Water skiing is popular above the dam at the Lucky Peak Reservoir. On the lower (warmwater) course of the river, low summer flows and poorer water quality from agricultural runoff limit fishery production. This section of river supports a fair fishery for largemouth bass, smallmouth bass, and channel catfish. Upstream from Star, the river is a coldwater stream and supports a greater variety of fish. The most prevalent species on this section is mountain whitefish, as well as hatchery-reared rainbow trout, wild rainbow trout, and brown trout. Upstream from Lucky Peak and Arrowrock reservoirs, the river and its tributaries contain excellent populations of wild rainbow trout, mountain whitefish, and bull trout.

rs about a quarter of Idaho. Three major volcanic buttes dot the plain east of Arco, the largest being Big Southern Butte. Most of Idaho's major cities are in the Snake River Plain, as is much of its agricultural land. Geology The Snake River Plain can be divided into three sections: western, central, and eastern. The western Snake River Plain is a large tectonic graben or rift valley filled with several kilometers of Lake Idaho sediments; the sediments are underlain by rhyolite and basalt, and overlain by basalt. The western plain began to form around 11–12 Ma (million years ago) with the eruption of rhyolite lavas and ignimbrites. The western plain is not parallel to North American Plate motion and lies at a high angle to the central and eastern Snake River Plain.

tward from northwest of the state of Wyoming to the Idaho-Oregon border. The plain is a wide, flat bow-shaped depression and covers about a quarter of Idaho. Three major volcanic buttes dot the plain east of Arco, the largest being Big Southern Butte. Most of Idaho's major cities are in the Snake River Plain, as is much of its agricultural land. Geology The Snake River Plain can be divided into three sections: western, central, and eastern. The western Snake River Plain is a large tectonic graben or rift valley filled with several kilometers of Lake Idaho sediments; the sediments are underlain by rhyolite and basalt, and overlain by basalt. The western plain began to form around 11–12 Ma (million years ago) with the eruption of rhyolite lavas and ignimbrites. The western plain is not parallel to North American Plate motion and lies at a high angle to the central and eastern Snake River Plain.

The Snake River Plain can be divided into three sections: western, central, and eastern. The western Snake River Plain is a large tectonic graben or rift valley filled with several kilometers of Lake Idaho sediments; the sediments are underlain by rhyolite and basalt, and overlain by basalt. The western plain began to form around 11–12 Ma (million years ago) with the eruption of rhyolite lavas and ignimbrites. The western plain is not parallel to North American Plate motion and lies at a high angle to the central and eastern Snake River Plain. Its morphology is similar to other volcanic plateaus such as the Chilcotin Group in south-central British Columbia, Canada. The eastern Snake River Plain traces the path of the North American Plate over the Yellowstone hotspot, now centered in Yellowstone National Park. The eastern plain is a topographic depression that cuts across Basin and Range mountain structures, more or less parallel to North American Plate motion. It is underlain almost entirely by basalt erupted from large shield volcanoes. Beneath the basalts are rhyolite lavas and ignimbrites that erupted as the lithosphere passed over the hotspot. The central Snake River plain is similar to the eastern plain but differs by having thick sections of interbedded lacustrine (lake) and fluvial (stream) sediments, including the Hagerman fossil beds. Island Park and Yellowstone Calderas formed as the result of enormous rhyolite ignimbrite eruptions, with single eruptions producing up to 600 cubic miles (2,500 km3) of ash. Henry's Fork Caldera, measuring 18 miles (29 km) by 23 miles (37 km), may be the largest symmetrical caldera in the world. The caldera formed when a dome of magma built up and then drained away. The center of the dome collapsed, leaving a caldera. Henry's Fork Caldera lies within the older and larger Island Park Caldera, which is 50 miles (80 km) by 65 miles (105 km).

xon signed an executive order. The order establishing the EPA was ratified by committee hearings in the House and Senate. The agency is led by its administrator, who is appointed by the president and approved by the Senate. Since January 29, 2025, the administrator is Lee Zeldin. The EPA is not a Cabinet department, but the administrator is normally given cabinet rank. The EPA has its headquarters in Washington, D.C. There are regional offices for each of the agency's ten regions, as well as 27 laboratories around the country. The agency conducts environmental assessment, research, and education. It has the responsibility of maintaining and enforcing national standards under a variety of U.S. environmental laws, in consultation with state, tribal, and local governments. EPA enforcement powers include fines, sanctions, and other measures. It delegates some permitting, monitoring, and enforcement responsibility to U.S. states and the federally recognized tribes. The agency also works with industries and all levels of government in a wide variety of voluntary pollution prevention programs and energy conservation efforts. The agency's budgeted employee level in 2023 was 16,204.1 full-time equivalent (FTE).

On July 9, 1970, Nixon proposed an executive reorganization that consolidated many environmental responsibilities of the federal government under one agency, a new Environmental Protection Agency. This proposal included merging pollution control programs from a number of departments, such as the combination of pesticide programs from the United States Department of Agriculture and the United States Department of the Interior. After conducting hearings during that summer, the House and Senate approved the proposal. The EPA was created 90 days before it had to operate, and officially opened its doors on December 2, 1970. The agency's first administrator, William Ruckelshaus, took the oath of office on December 4, 1970. EPA's primary predecessor was the former Environmental Health Divisions of the U.S. Public Health Service (PHS), and its creation caused one of a series of reorganizations of PHS that occurred during 1966–1973. From PHS, EPA absorbed the entire National Air Pollution Control Administration, as well as the Environmental Control Administration's Bureau of Solid Waste Management, Bureau of Water Hygiene, and part of its Bureau of Radiological Health. It also absorbed the Federal Water Quality Administration, which had previously been transferred from PHS to the Department of the Interior in 1966. A few functions from other agencies were also incorporated into EPA: the formerly independent Federal Radiation Council was merged into it; pesticides programs were transferred from the Department of the Interior, Food and Drug Administration, and Agricultural Research Service; and some functions were transferred from the Council on Environmental Quality and Atomic Energy Commission. Upon its creation, EPA inherited 84 sites spread across 26 states, of which 42 sites were laboratories.

1970s In its first year, the EPA had a budget of $1.4 billion and 5,800 employees. At its start, the EPA was primarily a technical assistance agency that set goals and standards. Soon, new acts and amendments passed by Congress gave the agency its regulatory authority. A major expansion of the Clean Air Act was approved in December 1970. EPA staff recall that in the early days there was "an enormous sense of purpose and excitement" and the expectation that "there was this agency which was going to do something about a problem that clearly was on the minds of a lot of people in this country," leading to tens of thousands of resumes from those eager to participate in the mighty effort to clean up America's environment. When EPA first began operation, members of the private sector felt strongly that the environmental protection movement was a passing fad. Ruckelshaus stated that he felt pressure to show a public which was deeply skeptical about government's effectiveness, that EPA could respond effectively to widespread concerns about pollution. The burning Cuyahoga River in Cleveland, Ohio, in 1969 led to a national outcry and criminal charges against major steel companies. The US Justice Department in late 1970 began pollution control litigation in cooperation with the new EPA. Congress enacted the Federal Water Pollution Control Act Amendments of 1972, better known as the Clean Water Act (CWA). The CWA established a national framework for addressing water quality, including mandatory pollution control standards, to be implemented by the agency in partnership with the states. Congress amended the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) in 1972, requiring EPA to measure every pesticide's risks against its potential benefits. In 1973 President Nixon appointed Russell E. Train to be the next EPA administrator. In 1974 Congress passed the Safe Drinking Water Act, requiring EPA to develop mandatory federal standards for all public water systems, which serve 90% of the US population. The law required EPA to enforce the standards with the cooperation of state agencies. In October 1976, Congress passed the Toxic Substances Control Act (TSCA) which, like FIFRA, related to the manufacture, labeling and usage of commercial products rather than pollution. This act gave the EPA the authority to gather information on chemicals and require producers to test them, gave it the ability to regulate chemical production and use (with specific mention of PCBs), and required the agency to create the National Inventory listing of chemicals. Congress also enacted the Resource Conservation and Recovery Act (RCRA) in 1976, significantly amending the Solid Waste Disposal Act of 1965. It tasked the EPA with setting national goals for waste disposal, conserving energy and natural resources, reducing waste, and ensuring environmentally sound management of waste. Accordingly, the agency developed regulations for solid and hazardous waste that were to be implemented in collaboration with states. President Jimmy Carter appointed Douglas M. Costle as EPA administrator in 1977.

Boise (locally also ) is the capital and most populous city in the U.S. state of Idaho. It is the county seat of Ada County. The population of the city was 235,685 at the 2020 census. The Boise metropolitan area, located in the Treasure Valley, includes five counties of Idaho with an estimated population of 846,000, the most populous metropolitan area in Idaho and 95th-most populous in the United States. Located on the Boise River in southwestern Idaho, it is 41 miles (66 km) east of the Oregon border and 110 miles (177 km) north of the Nevada border. Downtown Boise's elevation is 2,704 feet (824 m) above sea level. Boise is home to major employers in the technology, manufacturing, and service sectors, including companies such as Micron Technology and Hewlett-Packard.

an area in Idaho and 95th-most populous in the United States. Located on the Boise River in southwestern Idaho, it is 41 miles (66 km) east of the Oregon border and 110 miles (177 km) north of the Nevada border. Downtown Boise's elevation is 2,704 feet (824 m) above sea level. Boise is home to major employers in the technology, manufacturing, and service sectors, including companies such as Micron Technology and Hewlett-Packard.

...that the military should continue killing Indians 'until the last Indian in the Territories was either on his reservation or enriched the sagebrush with his decaying carcass.' ...if the Indians refused to move there, 'they will be killed or put on the reservation by force, and certainly shot if they don't stay there.' Furthermore, the editor continues, 'The idea that the Indians have any right to the soil is ridiculous. ...They have no more rights to the soil of the Territories of the United States than wolves or coyotes...' This would be our plan of establishing friendship upon an eternal basis with our Indians: Let all the hostile bands of Idaho Territory be called in (they will not be caught in any other manner) to attend a grand treaty; plenty of blankets and nice little trinkets distributed among them; plenty of grub on hand; have a real jolly time with them; then just before the big feast put strychnine in their meat and poison to death the last mother's son of them. At the same time, native warriors around the valley, under the leadership of Howluck also known as "Bigfoot" among white settlers, among others, waged an escalating and intensified guerrilla campaign of harassment of passerby caravans along the Oregon Trail. The United States Army also escalated and intensified "punitive expeditions" against formations of warriors and against civilian communities as well. This marked the start of the "unofficial" Snake War in 1866. This war lasted until 1868, and is statistically the deadliest of the Indian Wars in the West in terms of casualties. In the end, 1,762 men were counted as the casualties of this war from both sides. In 1868, Fort Hall Indian Reservation was established in Southeastern Idaho, about 220 miles upstream, according to the terms of Fort Bridger Treaty. The Boise Valley Shoshone and Bannock Tribes were not party to this treaty. Nevertheless, in April 1869, the United States Military embarked on a campaign of "Removal, rounding up of natives in the region including in and around Boise, and expelling them with cavalry escort to Fort Hall Indian Reservation. This period is known among the Shoshone and Bannock people as Idaho's Trail of Tears. Some of the natives managed to escape, and they ran to either Duck Valley or Fort McDermitt in Nevada. Incorporation and growth Boise's early growth was significantly driven by its role in supplying the nearby gold towns that sprung up in the 1860s northeast and then southwest of the town. Miners sometimes wintered in Boise and a number of early prominent businessmen were miners who settled in town in the years after the gold rush waned. By 1864 substantial agricultural production was underway on easily irrigated lands near the river and three canal companies had been incorporated. Early transportation improvements were largely a result of toll road franchises awarded by the territorial legislature starting in the 1860s. These first ran from Fort Boise to the mining centers in the Boise Basin and east to Rocky Bar and to Rattlesnake Station where they connected to the Oregon Trail. Territorial census records from a special 1864 enumeration list the population of Boise as 1,658, and an act of December 12, 1864, was the first attempt by the Idaho Territorial Legislature to incorporate the city. This was rejected by voters the following March. Two more unsuccessful attempts were made to organize a city administration by election before the 1866 version of the city charter was approved by voters on January 6, 1868. The growing number of homes and businesses, for which owners wanted proper legal title, may have contributed to the eventual success of incorporation. All of these rejected efforts to incorporate the city came after Boise had been controversially made the state capital in 1864 over strong opposition from northern Idaho interests. This decision reflected the rapid shift of population growth from north to south after the discovery of gold in southern Idaho. By 1868 Boise had over 400 permanent buildings with a wide range of commercial services. 1868 also marked the formal beginning of a long advocacy for railroad connections to other Idaho communities and, just as importantly, to other growing cities in the west such as Portland, Oregon. Competing railroad and western state government interests frustrated these efforts for many years. Designed by Alfred B. Mullett, the U.S. Assay Office at 210 Main Street was built in 1871 and today is a National Historic Landmark. It first began accepting gold and silver for purchase on March 2, 1872, largely eliminating the need to transport ore to the mint in San Francisco. A territorial penitentiary, now known as the Old Idaho State Penitentiary, opened the same month several miles east of town. Mining continued to be important to Boise's economic growth and periodic booms contributed to population growth as well, though production of gold and silver probably peaked in the 1860s. 1882's gold and silver production of $3,500,000 declined to $1,488,315 (including lead) by 1899. Boise began to earn its City of Trees nickname in this period with a popular focus on a range of tree planting projects. Thomas J. Davis planted several thousand fruit trees in 1864 and several other early businessmen either founded nurseries or orchards of their own. In the 1870s tree planting began in earnest in downtown Boise led by prominent hotels as well as businessmen and residents. In 1907 Davis donated 43 acres of his orchard property to the city for use as a park in the name of his wife Julia. Commercial agriculture continued to expand, but was slowed by the lack of reliable rail links to regional and national markets and by a lack of large scale irrigation projects, which themselves were often tied to hoped-for railroad projects for financing. A.D. Foote, a successful mining engineer, drew up plans to irrigate up to 500,000 acres immediately south of Boise in 1882, but progress was halting and smaller farms were the norm until after the turn of the century with most located near to the river bottom where soil was productive and irrigation more easily achieved. Fruit orchards proliferated and sugar beets, still an important agricultural industry in Idaho, began to be widely cultivated in the 1890s. Cattle and sheep farming became increasingly important as the century closed. With the exception of dairy, most livestock products were exported from Idaho, unlike other agricultural products which were still largely scaled to support local markets. The timber industry also increasingly thrived in the Boise market in the 1880s and 1890s. Large quantities of timber were exported from elsewhere in Idaho, but a growing Boise supported the expansion of Alexander Rossi's sawmill, first established in 1865. Prominent early Boisean William Ridenbaugh had inherited control of the canal now bearing his name from his uncle William Morris in 1878 and later partnered with Rossi to expand the sawmill capacity under the name Rossi and Ridenbaugh Lumber Company. Their materials supported bridge building and the rapid expansion of Boise in the 1890s. As with many early infrastructure ventures, electrification succeeded only after at least one false start. July 4, 1887, marked the start of electrical transmission from a plant located on the Bench. William Ridenbaugh provided expertise and manpower for the water supply and several months were spent rigging poles and lines from the Bench to the service area across the river. Additional electrical supplies allowed the building of an electric streetcar line in 1891. This ran without interruption until buses replaced the lines in 1927, tracking—and sometimes driving—the development of Boise and nearby communities. This system expanded over several decades, reaching into the North End, South Boise and across the river on Front St. A loop line, completed in 1912, ran as far as Caldwell and Nampa, providing transport throughout the valley. Three early trolley companies merged in 1912 to form the Idaho Traction Company with a depot at 7th and Bannock Streets downtown. Additional services and urban amenities arrived in the 1890s as Boise grew. Exploratory drilling for hot water was successful in 1890 and by the end of the decade many homes along Warm Springs avenue were being heated by this source. A natatorium was built in 1892 close to the source of the hot water near the Idaho State Penitentiary. Churches serving several denominations, a Jewish synagogue, a major hardware store and department store, a Masonic hall, the Columbia Theater, Saint Alphonsus' Hospital, a number of parochial and secular schools, a City Hall and a new Union Pacific passenger station, constructed when service was finally extended to downtown, were all built during the 1890s. Falk's Department Store sponsored a semi-professional baseball team representing Boise from at least 1892 and the city supported other organized sports as they became popular.

The National Environmental Policy Act (NEPA) is a United States environmental law designed to promote the enhancement of the environment. It created new laws requiring U.S. federal government agencies to evaluate the environmental impacts of their actions and decisions, and it established the President's Council on Environmental Quality (CEQ). The act was passed by the U.S. Congress in December 1969 and signed into law by President Richard Nixon on January 1, 1970. More than 100 nations around the world have enacted national environmental policies modeled after NEPA. NEPA requires federal agencies to evaluate the environmental effects of their actions. NEPA's most significant outcome was the requirement that all executive federal agencies prepare environmental assessments (EAs) and environmental impact statements (EISs). These reports state the potential environmental effects of proposed federal agency actions. Further, U.S. Congress recognizes that each person has a responsibility to preserve and enhance the environment as trustees for succeeding generations. NEPA's procedural requirements do not apply to the president, Congress, or the federal courts since they are not a "federal agency" by definition.

Environmental Quality (CEQ). The act was passed by the U.S. Congress in December 1969 and signed into law by President Richard Nixon on January 1, 1970. More than 100 nations around the world have enacted national environmental policies modeled after NEPA. NEPA requires federal agencies to evaluate the environmental effects of their actions. NEPA's most significant outcome was the requirement that all executive federal agencies prepare environmental assessments (EAs) and environmental impact statements (EISs). These reports state the potential environmental effects of proposed federal agency actions. Further, U.S. Congress recognizes that each person has a responsibility to preserve and enhance the environment as trustees for succeeding generations. NEPA's procedural requirements do not apply to the president, Congress, or the federal courts since they are not a "federal agency" by definition.

January 1, 1970. More than 100 nations around the world have enacted national environmental policies modeled after NEPA. NEPA requires federal agencies to evaluate the environmental effects of their actions. NEPA's most significant outcome was the requirement that all executive federal agencies prepare environmental assessments (EAs) and environmental impact statements (EISs). These reports state the potential environmental effects of proposed federal agency actions. Further, U.S. Congress recognizes that each person has a responsibility to preserve and enhance the environment as trustees for succeeding generations. NEPA's procedural requirements do not apply to the president, Congress, or the federal courts since they are not a "federal agency" by definition.

Ada County is located in the southwestern part of Idaho, United States. As of the 2020 census, the county had a population of 494,967, which by 2025 was estimated to have risen to 546,141. Ada County is by far the state's most populous county; it is home to 26.8% of the state's population. The county seat and largest city is Boise, which is also the state capital. Ada County is included in the Boise metropolitan area. The Ada County Highway District has jurisdiction over all the local county and city streets, except for private roads and state roads.

populous county; it is home to 26.8% of the state's population. The county seat and largest city is Boise, which is also the state capital. Ada County is included in the Boise metropolitan area. The Ada County Highway District has jurisdiction over all the local county and city streets, except for private roads and state roads.

ea. The Ada County Highway District has jurisdiction over all the local county and city streets, except for private roads and state roads. In the interior Pacific Northwest east of the Cascade Range, Ada County ranks second in population, behind Spokane County, Washington. History Ada County was created by the Idaho Territory legislature on December 22, 1864, partitioned from Boise County. It is named for Ada Riggs, the daughter of H. C. Riggs, a member of the legislature; he established the county and was a co-founder of Boise.

pa ( ) is the most populous city in Canyon County, Idaho, United States. The population was 100,200 at the 2020 census. It is Idaho's third-most populous city. Nampa is about 20 miles (32 km) west of Boise along Interstate 84, and 6 miles (9.7 km) west of Meridian. It is the second principal city of the Boise metropolitan area. The name "Nampa" may have come from a Shoshoni word meaning 'moccasin' or 'footprint'. According to toponymist William O. Bright, the name comes from the Shoshoni word /nampai/, meaning "foot".

History Nampa had its beginnings in the early 1880s when the Oregon Short Line Railroad built a line from Granger, Wyoming, to Huntington, Oregon, that passed through Nampa. In Nampa there is a history museum that marks the railroad's significance. More railroad lines sprang up through Nampa, making it an important railroad town. Alexander and Hannah Duffes established one of the town's first homesteads, eventually forming the Nampa Land and Improvement Company with the help of their friend and co-founder, James McGee. Despite the name, many early settlers called the town "New Jerusalem" because of its citizens' strong religious focus. After only a year the town grew from 15 homes to 50. As amenities were added, Nampa continued to grow, and it was incorporated in 1891. Downtown Nampa's street grid is oriented with the railroad tracks, which run northwest–southeast; this was done intentionally by Alexander Duffes to prevent accidents like one that occurred earlier in a town he had platted near Toronto, where a woman and her two children were killed by a train when their buggy wheel got stuck as they crossed the tracks. As the Oregon Short Line railroad originally bypassed Boise, Nampa has the fanciest of many railroad depots built in the area. Nampa gained attention in 1889 due to a purported archaeological discovery known as the Nampa figurine. George Frederick Wright wrote up details that year for the Boston Society of Natural History. The first elementary school was built in the 1890s. Lakeview School was on a hill on 6th Street and 12th Avenue North, with a view of Lake Ethel. Just after the school's centennial celebration, it was condemned as a school and sold to the First Mennonite Church. In 2008 the building was refurbished, and it is now used by the Idaho Arts Charter School. Lake Ethel, an irrigation reservoir, had long been the site of community picnics, and many citizens fished, swam, boated, and even hunted on it and its surrounding property. But the hunting didn't last long, as O. F. Persons, owner of the adjoining homestead, took offense when local hunters started shooting his pet ducks. The city later auctioned off the lake. E. H. Dewey (a former Nampa mayor) was the only bidder. But occasional flooding led to a series of lawsuits from neighbors. Dewey eventually drained Lake Ethel. Not long after, the city council became interested in buying back the Fritz Miller property as well as the Dewey home. Pressure had been building for more than four years. Nampa citizens wanted another park. On August 7, 1924, the city council passed an ordinance to purchase the Miller property and name it Lakeview Park. A bandstand was completed in 1928, and the municipal swimming pool opened on August 13, 1934. It is Nampa's largest park and many community celebrations are held there. Colonel William H. Dewey, a man who made a fortune mining in Silver City, built the Dewey Palace Hotel in 1902 for $250,000. He died in his hotel in 1903, leaving his son $1 million. The hotel survived the great fire of 1909, which burned several blocks of downtown Nampa, but was razed in 1963 after redevelopment plans failed. Relics from the hotel such as the chandelier and the hotel safe can be found at the Canyon County Historical Museum, which is in the old train depot on Front Street and Nampa City Hall. After demolition the location on First Street between 11th and 12th Ave. South was sold to private enterprise, including a bank and tire store, replacing this building with modern structures. A public-use postage stamp sized park was later placed across the street from the old palace property as a collaboration between the Downtown Alliance of Nampa (the local business council) and an Eagle Scout Project for the Boy Scouts of America. The park includes a large mural/wall sculpture of running horses commissioned for the project. A Carnegie library was built downtown in 1908; it burned down after the library moved in 1966. Nampa Public Library was then on the corner of 1st Street and 11th Avenue South in the old bank building. A new library, on 12th Avenue South, opened in 2015. Deer Flat Reservoir, an offstream irrigation storage reservoir, was constructed by the United States Bureau of Reclamation between 1906 and 1911. Known locally as Lake Lowell, it is surrounded by the Deer Flat National Wildlife Refuge, established in 1909 by President Theodore Roosevelt. The refuge is administered by the U.S. Fish and Wildlife Service. Lake Lowell is filled by the concrete New York Canal; the water is diverted from the Boise River a few miles below Lucky Peak Dam. In 1910, the Idaho State School and Hospital was built northwest of Nampa for the state's developmentally challenged population. It opened in 1918. The institution was largely self-sufficient, with a large farm staffed by the residents. The higher-functioning residents also cared for residents who could not care for themselves. The land for the farm was sold and is now golf courses (Centennial and Ridgecrest), and the residents no longer give primary care to other residents. The institution is modernized and remains in operation, though a few of the oldest buildings now house juvenile offenders. Nampa held an annual harvest festival and farmers' market from about 1908, a time of celebration and community fun. From this festival emerged the Snake River Stampede Rodeo in 1937, which continues to this day. It is one of the top 12 rodeos in the pro rodeo circuits. In 1913, a local congregation of the Church of the Nazarene built a small elementary school, which became to Northwest Nazarene College in 1915 and finally Northwest Nazarene University. As of 2025, the university has approximately 1,800 undergraduate and graduate students. Karcher Mall opened in 1965, the first enclosed shopping mall in the Treasure Valley. It was "the place to gather" for several decades until the Boise Towne Square mall was built in Boise in 1988, drawing business away. Karcher Mall was renamed District 208 in 2022. The Idaho Press-Tribune is the local newspaper for the Canyon County area.

Idaho Hispanic Community Center (IH2C) In 2003, the Hispanic Cultural Center of Idaho (HCCI) opened thanks to community support. It has recently transitioned back to the City of Nampa and was renamed the Idaho Hispanic Community Center (IH2C) and is home to the Idaho Hispanic Foundation. It hosts events, classes, and festivals, including Día de los Muertos, Hispanic Heritage Month, and Día Internacional de la Mujer. It serves as a meeting place for associations and groups. Displays of cultural history are available to the public. Nampa Train Depot Museum The Nampa Train Depot Museum is a historical depot with displays and archives of the area's railroad and cultural history. The Canyon County Historical Society saved the depot from demolition in 1972. Annual Festival of the Arts Nampa's Festival of the Arts, which began in 1987, is held in Lakeview Park every year and includes local art, music, dance, and food.

city in Idaho. As of the 2020 census, Caldwell had a population of 59,996. Caldwell is considered part of the Boise metropolitan area, and is the location of the College of Idaho. The city is located approximately 24 miles (39 km) west of Boise, and approximately 17 miles (27 km) east of the Oregon border. History The present-day location of Caldwell is along a natural passageway to the Inland and Pacific Northwest. Native American tribes from the west coast, north Idaho and as far away as Colorado came to the banks of the Boise River for annual trading fairs, or rendezvous. European and some Hawaiian explorers and traders soon followed the paths left by Native Americans and hopeful emigrants later forged the Oregon Trail and followed those paths to seek a better life in the Oregon Territory. Pioneers of the Trail traveled along the Boise River to Canyon Hill and forded the river close to the Silver Bridge on Plymouth Street. During the Civil War, the discovery of gold in Idaho's mountains brought a variety of new settlers into the area. Many never made it to the mines but settled along the Boise River and run ferries, stage stations, and freighting businesses. These early entrepreneurs created small ranches and farms in the river valleys. Caldwell's inception occurred largely as a result of the construction of the Oregon Short Line Railroad, which connected Wyoming to Oregon through Idaho. Robert E. Strahorn came to the Boise River Valley in 1883 to select a route for the railroad. He rejected the grade into Boise City as too steep and chose a site 30 miles to the west. He drove a stake into an alkali flat of sagebrush and greasewood and the City of Caldwell was platted. Caldwell was named after one of Strahorn's business partners, Alexander Caldwell, a former senator from Kansas. When Caldwell was platted in August 1883, its founder, the Idaho and Oregon Land Improvement Company, started persuading settlers and businessmen to move to the area. Within four months, Caldwell had 600 residents living in 150 dwellings, 40 businesses, a school, a telephone exchange, and two newspapers. On January 15, 1890, the Board of Commissioners of Ada County issued a handwritten order incorporating the City of Caldwell. The College of Idaho was founded in Caldwell in 1891. In 1892, Canyon County was established from a portion of Ada County, and Caldwell was named the county seat. Irrigation canals and waterways were constructed throughout Canyon County, providing the foundation for an agricultural economy. The Oregon Short Line Railroad became part of the larger Union Pacific Railroad network and in 1906 the Caldwell freight and passenger depot was constructed. Caldwell experienced moderate growth as an agricultural processing, commercial retail and educational center during the 20th century. In 2009, the City of Caldwell completed a revitalization project to restore Indian Creek, which runs through downtown Caldwell, but had been used for sewage disposal by local industries and been covered over.

History The present-day location of Caldwell is along a natural passageway to the Inland and Pacific Northwest. Native American tribes from the west coast, north Idaho and as far away as Colorado came to the banks of the Boise River for annual trading fairs, or rendezvous. European and some Hawaiian explorers and traders soon followed the paths left by Native Americans and hopeful emigrants later forged the Oregon Trail and followed those paths to seek a better life in the Oregon Territory. Pioneers of the Trail traveled along the Boise River to Canyon Hill and forded the river close to the Silver Bridge on Plymouth Street. During the Civil War, the discovery of gold in Idaho's mountains brought a variety of new settlers into the area. Many never made it to the mines but settled along the Boise River and run ferries, stage stations, and freighting businesses. These early entrepreneurs created small ranches and farms in the river valleys. Caldwell's inception occurred largely as a result of the construction of the Oregon Short Line Railroad, which connected Wyoming to Oregon through Idaho. Robert E. Strahorn came to the Boise River Valley in 1883 to select a route for the railroad. He rejected the grade into Boise City as too steep and chose a site 30 miles to the west. He drove a stake into an alkali flat of sagebrush and greasewood and the City of Caldwell was platted. Caldwell was named after one of Strahorn's business partners, Alexander Caldwell, a former senator from Kansas. When Caldwell was platted in August 1883, its founder, the Idaho and Oregon Land Improvement Company, started persuading settlers and businessmen to move to the area. Within four months, Caldwell had 600 residents living in 150 dwellings, 40 businesses, a school, a telephone exchange, and two newspapers. On January 15, 1890, the Board of Commissioners of Ada County issued a handwritten order incorporating the City of Caldwell. The College of Idaho was founded in Caldwell in 1891. In 1892, Canyon County was established from a portion of Ada County, and Caldwell was named the county seat. Irrigation canals and waterways were constructed throughout Canyon County, providing the foundation for an agricultural economy. The Oregon Short Line Railroad became part of the larger Union Pacific Railroad network and in 1906 the Caldwell freight and passenger depot was constructed. Caldwell experienced moderate growth as an agricultural processing, commercial retail and educational center during the 20th century. In 2009, the City of Caldwell completed a revitalization project to restore Indian Creek, which runs through downtown Caldwell, but had been used for sewage disposal by local industries and been covered over.

location of the College of Idaho. The city is located approximately 24 miles (39 km) west of Boise, and approximately 17 miles (27 km) east of the Oregon border. History The present-day location of Caldwell is along a natural passageway to the Inland and Pacific Northwest. Native American tribes from the west coast, north Idaho and as far away as Colorado came to the banks of the Boise River for annual trading fairs, or rendezvous. European and some Hawaiian explorers and traders soon followed the paths left by Native Americans and hopeful emigrants later forged the Oregon Trail and followed those paths to seek a better life in the Oregon Territory. Pioneers of the Trail traveled along the Boise River to Canyon Hill and forded the river close to the Silver Bridge on Plymouth Street. During the Civil War, the discovery of gold in Idaho's mountains brought a variety of new settlers into the area. Many never made it to the mines but settled along the Boise River and run ferries, stage stations, and freighting businesses. These early entrepreneurs created small ranches and farms in the river valleys. Caldwell's inception occurred largely as a result of the construction of the Oregon Short Line Railroad, which connected Wyoming to Oregon through Idaho. Robert E. Strahorn came to the Boise River Valley in 1883 to select a route for the railroad. He rejected the grade into Boise City as too steep and chose a site 30 miles to the west. He drove a stake into an alkali flat of sagebrush and greasewood and the City of Caldwell was platted. Caldwell was named after one of Strahorn's business partners, Alexander Caldwell, a former senator from Kansas. When Caldwell was platted in August 1883, its founder, the Idaho and Oregon Land Improvement Company, started persuading settlers and businessmen to move to the area. Within four months, Caldwell had 600 residents living in 150 dwellings, 40 businesses, a school, a telephone exchange, and two newspapers. On January 15, 1890, the Board of Commissioners of Ada County issued a handwritten order incorporating the City of Caldwell. The College of Idaho was founded in Caldwell in 1891. In 1892, Canyon County was established from a portion of Ada County, and Caldwell was named the county seat. Irrigation canals and waterways were constructed throughout Canyon County, providing the foundation for an agricultural economy. The Oregon Short Line Railroad became part of the larger Union Pacific Railroad network and in 1906 the Caldwell freight and passenger depot was constructed. Caldwell experienced moderate growth as an agricultural processing, commercial retail and educational center during the 20th century. In 2009, the City of Caldwell completed a revitalization project to restore Indian Creek, which runs through downtown Caldwell, but had been used for sewage disposal by local industries and been covered over.

105, which by 2025 was estimated to have risen to 275,123, making it the second-most populous county in Idaho. The county seat is Caldwell, and its largest city is Nampa. Canyon County is part of the Boise metropolitan area. History Hudson's Bay Company established Fort Boise in 1834 near what is now Parma, but abandoned it in 1855. Emigrants traveled through Canyon County on the Oregon Trail. Discovery of gold in the Boise Basin in 1862 brought settlement to the region again. The lower Boise River was fully contained within Boise County from 1863 until the formation of Ada County in 1864. Settlement of the lower Boise River west of Boise City was limited prior to the completion of the Oregon Short Line Railroad. Middleton was the first European settlement of Canyon County, starting in 1863. The 1870 Census for Ada County listed 76 residents of the Boise Valley, excluding Boise City and the 1880 Census listed 44 residents at Middleton. The arrival of the railroad at Caldwell led to the establishment of a town there as of August 1883. Businessmen James A. McGee and Alexander Duffes filed the plat for nearby Nampa in 1886. Parma was settled around the same time, with the Old Fort Boise post office being moved to the town's location; it was incorporated in 1904. Ada County established precincts for each of the settlements with a combined 1890 Census population of 2,311. Significant settlement of Greenleaf and Notus started around 1904 with the two settlements listed as precincts at the 1910 census. Notus was incorporated in 1921 while Greenleaf was incorporated prior to 1980. Melba was incorporated in 1912 while Wilder was incorporated in 1919. The City of Star annexed a portion of territory in northeast Canyon County prior to 2007, becoming the county's ninth incorporated city. The majority of Star is located within Ada County. The Idaho Legislature created Canyon County from Ada County in an act approved March 7, 1891, effective at the November 26, 1892, election. Caldwell was established as the county seat. The county originally contained all of Canyon and Payette counties and part of Gem; Gem County formed in 1915 and Payette County in 1917.

History Hudson's Bay Company established Fort Boise in 1834 near what is now Parma, but abandoned it in 1855. Emigrants traveled through Canyon County on the Oregon Trail. Discovery of gold in the Boise Basin in 1862 brought settlement to the region again. The lower Boise River was fully contained within Boise County from 1863 until the formation of Ada County in 1864. Settlement of the lower Boise River west of Boise City was limited prior to the completion of the Oregon Short Line Railroad. Middleton was the first European settlement of Canyon County, starting in 1863. The 1870 Census for Ada County listed 76 residents of the Boise Valley, excluding Boise City and the 1880 Census listed 44 residents at Middleton. The arrival of the railroad at Caldwell led to the establishment of a town there as of August 1883. Businessmen James A. McGee and Alexander Duffes filed the plat for nearby Nampa in 1886. Parma was settled around the same time, with the Old Fort Boise post office being moved to the town's location; it was incorporated in 1904. Ada County established precincts for each of the settlements with a combined 1890 Census population of 2,311. Significant settlement of Greenleaf and Notus started around 1904 with the two settlements listed as precincts at the 1910 census. Notus was incorporated in 1921 while Greenleaf was incorporated prior to 1980. Melba was incorporated in 1912 while Wilder was incorporated in 1919. The City of Star annexed a portion of territory in northeast Canyon County prior to 2007, becoming the county's ninth incorporated city. The majority of Star is located within Ada County. The Idaho Legislature created Canyon County from Ada County in an act approved March 7, 1891, effective at the November 26, 1892, election. Caldwell was established as the county seat. The county originally contained all of Canyon and Payette counties and part of Gem; Gem County formed in 1915 and Payette County in 1917.

2000 census As of the 2000 census, there were 131,441 people, 45,018 households and 33,943 families living in the county. The population density was 223 people per square mile (86 people/km2). There were 47,965 housing units at an average density of 81 units per square mile (31 units/km2). The racial makeup of the county was 83.10% White, 0.32% Black or African American, 0.85% Native American, 0.80% Asian, 0.13% Pacific Islander, 12.17% from other races, and 2.62% from two or more races. Hispanic or Latino of any race were 18.61% of the population. 15.9% were of German, 12.7% English, 10.3% American and 7.6% Irish ancestry. There were 45,018 households, of which 39.80% had children under the age of 18 living with them, 60.70% were married couples living together, 10.10% had a female householder with no husband present, and 24.60% were non-families. 19.80% of all households were made up of individuals, and 8.40% had someone living alone who was 65 years of age or older. The average household size was 2.85 and the average family size was 3.28. 30.90% of the population were under the age of 18, 10.70% from 18 to 24, 28.30% from 25 to 44, 19.10% from 45 to 64, and 11.00% who were 65 years of age or older. The median age was 30 years. For every 100 females, there were 98.70 males. For every 100 females age 18 and over, there were 96.30 males. The median household income was $35,884 and the median family income was $40,377. Males had a median income of $29,418 compared with $22,044 for females. The per capita income for the county was $15,155. About 8.70% of families and 12.00% of the population were below the poverty line, including 14.50% of those under age 18 and 10.70% of those age 65 or over. Communities Cities Unincorporated communities Bowmont Huston Roswell Sunnyslope Walters Ferry, Idaho Politics Like the majority of Idaho, Canyon County is reliably Republican by comfortable margins. The last time a Democratic candidate carried the county was in 1936 by Franklin D. Roosevelt.

Meridian is a city located in Ada County, Idaho, United States. The population was 117,635 at the 2020 census, making it the second most populous city in the county and Idaho, after Boise, the state capital.

Rail transportation (1908–28) Following the raising of $4,000 to lay the Interurban rail line from Onweiler (Meridian and Ustick Roads), the tracks were completed into the village center. Turning east on Broadway and ending at East Second, the last car would spend the night in Meridian before returning to Boise early the next morning with passengers and freight. The interurban Station and Generator building (west one-third of the old library at Meridian and Idaho Streets) was built in 1912, and the line continued on to Nampa via Meridian. The tracks down Broadway were not used after 1912. The Interurban Company entered into receivership and closed in 1928 after 20 years of providing continuous transportation to neighboring towns. It was Meridian's main connection to the area outside the local community. The Union Pacific Railroad spur opened in 1900 and is currently operated by the Boise Valley Railroad. Many industrial customers continue to ship forest, agricultural, and chemical products along this corridor. Creamery (1929–70) The city's official website describes the history of the Ada County Dairymen's cooperative creamery as follows:The lowest days of the Great Depression brightened for area dairymen when the Ada County Dairymen's cooperative creamery began operation in 1929. It provided milk checks to those who were members of the cooperative, enabling them to pay their taxes and provide food for their families. Other community members hauled milk to the creamery and were employed by the creamery, whose product was Challenge Butter. The creamery ran seven days a week for 40 years. Additions and improvements were made while the plant was in full operation. Later years saw the Wyeth Laboratories affiliate with the creamery to manufacture SMA baby formula.

Creamery (1929–70) The city's official website describes the history of the Ada County Dairymen's cooperative creamery as follows:The lowest days of the Great Depression brightened for area dairymen when the Ada County Dairymen's cooperative creamery began operation in 1929. It provided milk checks to those who were members of the cooperative, enabling them to pay their taxes and provide food for their families. Other community members hauled milk to the creamery and were employed by the creamery, whose product was Challenge Butter. The creamery ran seven days a week for 40 years. Additions and improvements were made while the plant was in full operation. Later years saw the Wyeth Laboratories affiliate with the creamery to manufacture SMA baby formula.