Misplaced Pages

#174825

80-582: Salmon once spawned in the far reaches of California's rivers but with the era of dam building came the loss of spawning ground. Upstream rivers have been damned to control flooding. This has greatly diminished the availability of appropriate habitat for the fish to spawn and live in. Historically, Chinook salmon would migrate annually up the American river to the forks and streams in the Sierra Nevada mountains but Nimbus and Folsom Dams now limit them to

160-445: A nautical chart . The time of slack water, particularly in constricted waters, does not occur at high and low water, and in certain areas, such as Primera Angostura , the ebb may run for up to three hours after the water level has started to rise. Similarly, the flood may run for up to three hours after the water has started to fall. In 1884, Thornton Lecky illustrated the phenomenon with an inland basin of infinite size, connected to

240-477: A balanced, healthy ecosystem. Non-native, and sometimes invasive, species have been introduced to the American River ecosystem. These exotic species have no natural predators and combat with native species for sun, space, and nutrients, causing substantial problems for the native plant life and the entire bionetwork. The American River Parkway Foundation, in collaboration with Sacramento County Parks, manages

320-402: A day and grow rapidly. Once the fish are ready to begin their outmigration to the ocean, at 60 fish to the pound for salmon and 4 fish to the pound for steelhead trout, they are loaded into tanker trucks and transported to the river for release. From here they make their way downstream and eventually journey out to sea. The hatchery releases Chinook salmon from three locations. The first location

400-524: A large dam on the American River by the late 19th century. During the 20th century, the American River was extensively developed for flood control, hydroelectricity production and irrigation. Folsom Dam is the primary flood-control facility for Sacramento. The numerous hydroelectric dams upstream on the Middle and South Forks are not constrained by flood control requirements; rather, the needs of electricity and water supply govern their operation. Folsom Dam

480-492: A main source of flood control. As shown in figure 3, the weirs guide salmon in the direction of the ladder to enter the hatchery, preventing them from travelling upstream. From November through March river water flows down the fish ladder to encourage fish to enter and climb the steps to the hatchery. The gate at the foot of the ladder is closed when the holding pool at the top is full in order to prevent overcrowding. Ripe (ready to spawn) fish are brought from this holding pool into

560-423: A maximum or minimum (i.e., at that moment in time, not rising or falling). Some localities have unusual tidal characteristics, such as Gulf St Vincent , South Australia, where the amplitudes of the main semi-diurnal tide constituents are almost identical. At neap tides the semi-diurnal tide is virtually absent, resulting in the phenomenon known as a "dodge tide" —a day-long period of slack water—occurring twice

640-714: A permanent outpost here. In 1839, Swiss immigrant John Sutter established the New Helvetia settlement on the American River, near the present-day location of central Sacramento. In 1848, following the Mexican–American War , California was ceded to the United States in the Treaty of Guadalupe Hidalgo . Just weeks later, James W. Marshall , an employee of Sutter, discovered gold on the South Fork, starting

720-482: A series of nests called beds. During development small salmon need side pools on the river in which to rest in the cool shade and to hide from predators. Thick vegetation along the waters edge provides shade to keep the water cool enough to survive in warmer months. Salmon require 7ppm of oxygen and a pH between 6.5 and 8. Many spawning habitats have been destroyed or are threatened by development, water pollution, water diversions, and erosion and siltation. Because of this

800-551: A sharp curve northward to descend into Tahoe Valley. The South Fork has multi-use recreational areas, including the Rubicon Trail for motorized adventuring and whitewater rafting venues. The South Fork also features the historic town of Coloma , where the California Gold Rush began in 1848. Trout fishing and recreational gold panning are popular activities on the South Fork. The Silver Fork American River

880-464: A single location to minimize predation from birds, seals, and other fish. Salt is added to the hauling trucks as an osmoregulatory enhancer and antistressor, at 0.5 to 1.0 mg/L, in addition to food particles. Heavy water flows during the winter have eroded the foundation of the weir and piers, prompting major repairs in 1963, 1982, 1986, and 1999. Erosion holes in the weir were a major problem because they allowed adult Chinook salmon to pass through

SECTION 10

#1732772994175

960-452: A threatened anadromous fish species that have historically used the American River as a location for an important part of their life cycle while in freshwater. The American River, however, has lost some of its natural flow and riverbed because of water projects and diversions. The American River Salmonid Spawning and Rearing Habitat Restoration project, which started in 2008, entails the placement of gravel to provide adequate habitat conducive to

1040-454: A vessel out of a channel into danger. In many locations, in addition to the tidal streams there is also a current causing the tidal stream in the one direction to be stronger than, and last for longer than the stream in the opposite direction six hours later. Variations in the strength of that current will also vary the time when the stream reverses, thus altering the time and duration of slack water. Variations in wind stress also directly affect

1120-476: A weir improvement project. Members of the workshop came up with the following potential solutions: Reclamation asked the California Department of Water Resources Fish Passage Improvement Program for potential improvements for redirecting salmon to the hatchery. The DWR suggested for the fish ladder to be extended to the stilling basin downstream of Nimbus Dam, with the dam becoming the barrier for

1200-605: Is 7 miles (11 km) downstream from Folsom Dam and helps to stabilize peaking power releases from Folsom Dam, and divert water into the Folsom South Canal for irrigation. Eight hydroelectric plants on the South Fork are operated by Sacramento Municipal Utility District (SMUD) as the Upper American River Project . These plants are fed by a series of reservoirs including Loon Lake , Ice House Reservoir and Union Valley Reservoir . With

1280-605: Is a 20-mile-long (32 km) tributary of the South Fork American River, that has its origin at Silver Lake The American River watershed crosses multiple climate zones due to the large range in elevations. The climate of the lower American River valley is Mediterranean and temperate grassland. Sacramento County in particular, where the main stem American River is located, is known for its cool winters and hot summers, with low average precipitation. The North, Middle and South Forks originate in alpine zones along

1360-519: Is also taking measures to install chillers and UV filtration to ensure acceptable water temperatures for eggs and fry in light of the reduced snow pack and warmer temperatures associated with climate change. The hatchery supplements the natural population but concerns remain regarding its potential effects. One concern is how the hatchery population relates to the natural population. Main concerns focus on competition, predation, effects of behavior, and potential disease. Hatchery fish populations may react to

1440-559: Is part of the San Francisco Bay watershed. This river is fed by the melting snowpack of the Sierra Nevada and its many headwaters and tributaries, including its North , Middle , and South Forks . The American River is known for the discovery of gold at Sutter's Mill in Coloma in 1848 that started the California Gold Rush and contributed to the initial large-scale settlement of California by White American migrants. Today,

1520-616: Is the Lower American River at the Sunrise Avenue river access, where 1.33 million are released annually. The second location is found in the Lower American River under the Jibboom Street Bridge, where another 1.33 million salmon are released. These two locations use a direct release method from trucks in which the fish are transported through long tubes. The remaining 1.33 million salmon are released to

1600-539: Is the longest tributary of the American River, at 88 miles (142 km). It begins at an elevation of about 7,900 feet (2,400 m) near Lake Tahoe in Placer County at Mountain Meadow Lake, just northeast of Granite Chief and immediately due west of Palisades Tahoe (formerly Squaw Valley) Ski Resort . It flows westward through remote wilderness areas. The North Fork and its tributaries provides one of

1680-414: Is utilized for a variety of recreational uses. Locals and travelers alike use the river's scenic landscape for bird watching, hiking, biking, fishing, river rafting, kayaking, and more. The American River is a clean, biodiverse river that people can safely swim in and do other recreational activities in. The American River is specifically known for its whitewater rafting. The South Fork has Class III rapids,

SECTION 20

#1732772994175

1760-675: The Auburn State Recreation Area . The Western States Trail hosts multiple annual endurance events, including the Tevis Cup equestrian trail ride, and the world-famous Western States 100-Mile Trail Run, both beginning at Squaw Valley and leading to Auburn via remote wilderness trails. The South Fork is 87 miles (140 km) long. It originates at Echo Summit near Echo Lake south of Lake Tahoe in El Dorado County , just south of where U.S. Route 50 makes

1840-472: The CSPR (California Department of Parks and Recreation) . Reclamation made an environmental assessment draft that was never publicly drafted. The draft outlined an extended fish ladder design, a possible weir replacement, and a no action approach. The need for further analysis of potential project impacts, potential changes to CDFG fishing regulations, and public and agency interests led to Reclamation initializing

1920-419: The California Gold Rush . Although miners looking to extract gold worked all three forks of the American River, the South Fork held the richest deposits. As the easily accessible placer gold was played out, large companies used hydraulic mining to access gold buried deeper in the soil. This large and extensive mining practice washed away entire mountainsides and heavily polluted all the waterways, including

2000-507: The EIS (Environmental Impact Statement)/EIR (Environmental Impact Report) process in April 2009. The process is designed to find the project's potential consequences on the environment and identify ways to mitigate them. The final EIS/EIR report was published on August 11, 2011. It considered three alternatives for the weir improvement project. Alternative 1 modified the fish passageway by extending

2080-499: The Middle Fork Project , whose primary reservoirs are situated at French Meadows Reservoir and Hell Hole Reservoir . The Middle Fork Project generates 1.03 billion kilowatt hours each year and also provides 120,000 acre-feet (0.15 km ) of domestic water supply. The American River Parkway is a 23-mile (37 km) stretch along the American River and includes about 5,000 acres (20 km ) of embankment between

2160-653: The Mokelumne Wilderness , where it meets the watersheds of the Mokelumne and Carson Rivers . Lands east of the American River watershed divide drain into Lake Tahoe , which flows into the Truckee River. During most years, a significant snow-pack builds up in the Sierra Nevada which provides water during the hot, dry summers. In warmer winters much of the precipitation may fall as rain instead, causing flooding, but resulting in lower summer flows due to

2240-629: The Nimbus Fish Hatchery and where the American River and the Sacramento River converge. The Sacramento County Regional Parks owns most of the land that is operated by the American River Parkway. This area serves the citizens of Sacramento and visitors from away with access to the river and parks, picnic areas, biking and jogging paths, trails for hiking, and habitat for fish and wildlife. Chinook Salmon are

2320-716: The San Pablo Bay via acclimation net pens. Trucks load the salmon into the net pens during a slack tide at Mare Island near the entrance of the Napa River . As the ebb tide begins, boats transport the pens into the Carquinez Strait , in which the fish sit for approximately two hours. The tide takes the net pen to the mouth of the San Pablo Bay where the fish are released. The Hatchery never performs salmon releases for more than two consecutive days at

2400-709: The Tahoe and Eldorado National Forests . The North and Middle Forks join near Auburn , and continue downstream as the North Fork, although the Middle Fork carries a higher volume of water. The North and South Forks join in Folsom Lake . All three forks are known for their verdant canyons, forested ridges, massive rock formations, trails, back-country winter adventuring among snowy peaks, fishing and white water rafting . There are various fish species that live within

2480-487: The confluence with the Middle Fork American River at Auburn . Below the confluence, the North Fork continues several miles until reaching Folsom Lake. Both the North Fork and Middle Fork feature archaeological and historic sites of ancient Native American culture and 1850s Gold Rush habitation. The Middle Fork is 62 miles (100 km) long. It originates a mere 1.7-mile (2.7 km) from

Nimbus Fish Hatchery - Misplaced Pages Continue

2560-535: The 1999 workshop. In December 2003, two public meetings were held in Rancho Cordova to assess the community's questions and concerns as well as further alternative suggestions for the weir. In 2006, Reclamation launched a series of workshops as part of a Project Alternatives Solutions Study to help with alternatives. The workshops took input from the USFWS (United States Fish and Wildlife Service) , NMFS, CDFG, and

2640-432: The American River area near present-day Sacramento for at least 5,000 years before Spaniards and colonial Americans arrived in the region; human habitation in what some consider present-day Northern California is believed to date back as far as 12,000 years. These tribes have utilized the vast amount of resources of the American River for shelter, clothes, baskets, and other goods. Europeans and their descendants arrived in

2720-546: The American River include: Native plants include: Historically, the American River, like many other rivers in California, were modified by the dams of beavers, until European trappers removed many of the beavers from their native habitat for their fur. Since the California Gold Rush was centered in an area that included the American River basin, it was one of the earlier California rivers to be populated, beginning at Leidesdorff Ranch, owned by William Leidesdorff . Water

2800-522: The American River such as Chinook Salmon and Steelhead Trout. The American River headwaters lie along about 50 miles (80 km) along the Sierra Crest from Mount Lincoln in the north ( 39°17′16″N 120°19′41″W  /  39.28778°N 120.32806°W  / 39.28778; -120.32806 ) where it adjoins the watersheds of the South Yuba and Truckee Rivers , to Winnemucca Lake in

2880-489: The American River, creating an environmental disaster for inhabitants, fish, birds, and other flora and fauna. During the Great Flood of 1862 the American River flooded massively, putting much of Sacramento under water for three months. Newly elected Governor Leland Stanford had to travel to his inauguration by rowboat; shortly after, the state government moved temporarily to San Francisco. A significant contributor to

2960-607: The Hatchery fishway outfall. Under Alternative 1C, the current fishing regulations would need to change to close fishing between Nimbus Dam and the USGS (United States Geological Survey) gaging station cable crossing year-round. The changing of these regulations would require the approval of the Fish and Game Commission. Alternative 2 would install a new weir structure upstream while removing the current one, offering fish more entrances into

3040-571: The Lower American River. In 1955, the Nimbus Hatchery, weir , and fish ladder became operational to mitigate the impacts the newly constructed Folsom and Nimbus Dams have on Chinook Salmon and Steelhead Trout populations in the American River. Those salmon and steelhead that cannot find a place to spawn in the approximately seven miles of remaining habitat below the dams will climb the fish ladder to Nimbus Hatchery, where they will be artificially spawned and their eggs reared for release back into

3120-553: The Middle Fork has Class IV rapids, and the North Fork has Class IV spring run-off rapids. All three rivers also feature Class II sections. The areas with rapids still feature scenic views and wildlife, which is what makes it the most popular whitewater rafting location in California The California Office of Environmental Health Hazard Assessment has issued safe eating advice based on levels of mercury and polychlorinated biphenyl for fish caught from

3200-467: The Sierra Crest and flow through subalpine, montane and temperate coniferous forests. In the foothills, oak woodland and grassland are dominant. The region is prone to seasonal drought conditions, as about 90 percent of precipitation falls as rain and snow between the months of November and April. Much of the Central Valley was historically wetlands and has extremely fertile soil; today,

3280-594: The South Fork. While they are not operated by SMUD, they depend on the releases from SMUD reservoirs to generate electricity. The El Dorado Irrigation District owns the Akin Powerhouse, and PG&E owns the Chili Bar Powerhouse. The Rock Creek Powerhouse is owned by Sithe Energies. The Placer County Water Agency operates five hydroelectric power plants on remote sections of the Middle Fork as

Nimbus Fish Hatchery - Misplaced Pages Continue

3360-457: The area of the Central Valley surrounding the American River was home to vast marshes , which would have given the river the appearance of a series of lakes. During the 1820s, Jedediah Smith led an expedition to the American River with the goal of finding a safe route for colonizers across the Sierra Nevada. After a failed attempt to cross the mountains via the South Fork of the American River, Smith's group managed to cross via Ebbetts Pass on

3440-473: The area to trap beaver and otter. During one of these expeditions, smallpox or malaria were accidentally introduced to the local Native peoples, who had no immunity to European diseases. Some accounts suggest as much as 70 percent of the indigenous population was wiped out. The surviving natives became hostile to exploitative European settlers and traders for quite some time, and prevented the HBC from establishing

3520-490: The consequences of weir repairs and the safety of federally protected aquatic life. The NMFS requested that “. . . Reclamation and CDFG develop a long-term solution and a schedule for implementation to minimize flow fluctuations associated with the installation and removal of the Nimbus Fish Hatchery fish diversion weir racks and pickets by June 2000” (NMFS 1999). In 1999, Reclamation hosted a workshop to plan for

3600-626: The designation "Recreational River" under both the California Wild and Scenic Rivers Act (1972) and the National Wild and Scenic Rivers Act (1980). This status provides state and national recognition to protect the river's outstanding scenic, fish and wildlife, historic, cultural, and recreational values. The American River is fed by its North, Middle, and South forks, which are located in El Dorado County , Placer County , and Sacramento County . The river's three forks originate in

3680-446: The diversity of habitats and biodiversity by supporting protected native or endemic species that are listed as endangered or threatened. The American River Conservancy protects the American River watershed to preserve the cultural and historic values of the river systems and the landscapes surround them. They are also invested in keeping the American River for recreational activities as well as its natural scenic views. The American River

3760-538: The exception of Folsom Lake, Union Valley is the largest in the American River watershed, storing 277,000 acre-feet (0.342 km ) of water. The Upper American River Project produces 1.8 billion kilowatt hours in an average year, enough for about 20 percent of Sacramento's electricity needs. The SMUD plants are run on a peaking basis, although recreational boating and environmental flow requirements constrain their operation slightly. A number of run-of-the-river hydroelectric plants are located further downstream on

3840-639: The fish hatchery programs have been put in place to sustain fish populations. The following table displays estimated numbers and geographic distributions of Chinook salmon runs to the lower American River (USFWS and DFG 1953): The hatchery is operated by the California Department of Fish and Wildlife and owned and funded by the Bureau of Reclamation as mitigation for Folsom and Nimbus Dams. To meet Reclamation's requirements, 4 million juvenile Chinook salmon and 430,000 steelhead trout are raised in

3920-463: The fish ladder to Nimbus Dam and removing the current diversion weir structure. Alternative 1 was composed of two alternatives - 1A and 1C - because the CDFG fishing closure regulations were subject to change. Alternative 1A would not impact the established American River fishing regulations. 1A would have fishing closures apply year-round within a 250 foot radius of the extended fish passageway entrance and

4000-477: The flood damage was the debris washed down by hydraulic mining, which had choked the river channel and reduced its capacity to drain floodwaters. In response, the city of Sacramento undertook a massive project to raise its streets and buildings as much as 9.5 feet (2.9 m). Many of original sidewalks and the first floors of buildings remain as subterranean spaces underneath today's streets. The lower American River has been one of seven California rivers to achieve

4080-455: The hatchery and then released to complete their journey down the river. Reclamation, the USFWS, and CDFW (formerly CDFG) decided for the Hatchery to be able to hold 30 million Chinook salmon eggs with the ability to expand to 50 million if necessary. The hatchery is part of a greater interconnected network within the region. The dams upstream from the hatchery generate power, supply water, and are

SECTION 50

#1732772994175

4160-792: The hatchery before being released into the American River. To measure the success of hatchery programs and release points, one quarter of the salmon and all of the steelhead have their adipose fin clipped and a coded wire tag implanted in their nose which contains information on hatchery of origin, age, and release site. Nimbus Fish Hatchery is one of many interconnected Hatcheries in the state of California that are put in place to mitigate impacts on sensitive species. Other Salmon and Steelhead Hatcheries include: Iron Gate Fish Hatchery, Mad River Fish Hatchery, Trinity River Salmon and Steelhead Hatchery, Feather River Fish Hatchery, Warm Springs Fish Hatchery, Silverado Fisheries Base, Merced River Salmon Hatchery, and Mokelune River fish Hatchery. The Nimbus Fish Hatchery

4240-470: The hatchery spawning deck, where workers collect eggs from the females and milt from the males. Fertilized eggs are placed in hatching jars, with river water upwelling from the bottom to simulate natural conditions. When the eggs are ready to hatch the jars are tipped into large tubs where the baby fish (alevin) will remain while they absorb their yolk sacs and become free-swimming. They are then moved outside to raceway pools where they are fed multiple times

4320-579: The headwaters of the Stanislaus River , becoming the first non-Natives to do so. In Smith's honor the Spanish settlers named the river Rio de los Americanos (American River). During this time, Alta California was part of New Spain ; however in 1822, Mexico gained its independence from Spain and took control of California. In the 1830s, fur trappers of the Hudson's Bay Company (HBC) visited

4400-405: The height of the tide, and the inverse relationship between the height of the tide and atmospheric pressure is well understood (1 cm change in sea level for each 1 mb change in pressure) while the duration of slack water at a given location is inversely related to the height of the tide at that location. Slack water is different from the 'stand of the tide', which is when tide levels 'stand' at

4480-558: The invasive plants on the American River. Fourteen environmental watershed groups are shown to be active in the Upper American River Watershed by the Adopt A Watershed Program of the U.S. EPA . The Upper American River Foundation is a prominent one. There are over 40 species of native and non-native fish in the American River, including: Wildlife in the American River basin includes: Invasive plants on

4560-515: The lack of snow. Due to California's highly variable weather patterns, runoff volumes in the American River can rise and fall drastically from one year to the next. Below Folsom Dam , the river passes through an urbanized area but is buffered by a riparian park, the American River Parkway . Containing fishing and family-oriented rafting, and paved bicycling and multi-use trails, it runs 30.6 miles (49.2 km) from Folsom Lake to

4640-482: The ladder. The structure would perform the same function as the old weir in preventing adult fish from moving upstream. The new weir would be permanent, and would no longer require flow blockages or installation services. The fishing restrictions within a 250 foot radius of the fish ladder entrance and outfall would remain. The No Action Alternative would leave the existing weir unchanged. Costly, frequent, and disruptive weir repairs would be expected to continue throughout

4720-511: The late 18th century. The Nisenan call the river Kum Sayo , meaning ' roundhouse river'. Spanish explorer Gabriel Moraga named the river Rio de las Llagas (River of Wounds) when he passed through the area in the early 1800s, perhaps due to hostile relations with local native peoples. Another member of the expedition recorded the name as Rio de los Lagos (River of the Lakes) which may or may not have been an error, as in those times

4800-604: The most biologically diverse habitats in North America. The North Fork features scenic multi-use trails along forested ridge-tops and riparian corridors. It flows freely as a designated National Wild and Scenic Rivers System river until reaching the North Fork Dam, which was built to contain mining debris. This dam creates the small Lake Clementine just north of the Foresthill Bridge and upstream of

4880-410: The natural environment differently than naturally spawned fish do. They are coming from a controlled environment in which food was readily available, which affects their size and relative fitness. To better understand the impacts of the hatchery population, research teams are continually studying salmon populations. Hatchery practices are evolving and will continue to evolve as we come to better understand

SECTION 60

#1732772994175

4960-597: The needs and life history of these fish. 38°38′00″N 121°13′31″W  /  38.6333°N 121.2252°W  / 38.6333; -121.2252 American River The American River is a 30-mile-long (50 km) river in California that runs from the Sierra Nevada mountain range to its confluence with the Sacramento River in downtown Sacramento . Via the Sacramento River, it

5040-491: The previously incoming tide brings clear water with it. Following low tide, visibility can be reduced as the ebb draws silt, mud, and other particulates with it. In areas with potentially dangerous tides and currents, it is standard practice for divers to plan a dive at slack times. For any vessel, a favourable flow will improve the vessel's speed over the bottom for a given speed in the water. Difficult channels are also more safely navigated during slack water, as any flow may set

5120-500: The rearing habitat for the anadromous fish and increase biodiversity of the American River. The American River Conservancy works to conserve the wildlife and their aquatic and terrestrial habitats and resources around the American River and Consumnes watersheds. They have protected over 27,000 acres (110 km ) since their inception in 1989. The land they protect helps the American River water quality by conserving and restoring wet meadows , wetlands, and riparian areas. They conserve

5200-567: The removal of the existing weir would be considered by Reclamation once the new passageway is deemed successful for two seasons. According to the Nimbus Hatchery Fish Passage Project Milestone Calendar , the methods of implementation are continuing to be evaluated through 2020. Each year the hatchery raises around 4 million baby salmon. Winter runs of steelhead trout produce nearly 430,000 annually. Fish grow to about 4-6 inches in length at

5280-414: The river still has high quality water, and it is the main source of drinking water for Sacramento . This river is dammed extensively for irrigation, flood control , and hydroelectric power . The American River watershed supports Mediterranean, temperate, and montane ecosystems, and it is the home of a diverse array of fish and wildlife. The Maidu , Miwok , Nisenan , and Wintun peoples have inhabited

5360-483: The river's confluence with the Sacramento River. The American River Parkway incorporates historic Leidesdorff Ranch, a 35,000-acre (140 km ) cattle and wheat agribusiness owned by the "African Founding Father of California." Jedediah Smith Memorial Trail , a meandering 32-mile (51 km) cycle path, hugs the river bank from Old Sacramento to Folsom Lake . The trail was named for Smith and his men, who camped and trapped along its banks in 1828. The North Fork

5440-495: The river. Specific production numbers to compensate for habitat loss were decided during the Fish and Wildlife Coordination Act Report led by the United States Bureau of Reclamation and the California Department of Fish and Wildlife on August 14, 1946. Salmon return from the ocean to the rivers of their birth in search of specific spawning habitat. They seek out gravel 2-4 inches in diameter with which to construct

5520-400: The salmon. This suggestion held similarity to two other plans, except the other two used trucks or water channels to transport the fish instead of a fish ladder. After reviewing both options, Reclamation prepared a fish ladder design extending from the hatchery to the south side of Nimbus Dam's stilling basin. Reclamation began weir planning studies in 1996 and continued after the conclusion of

5600-458: The salmonid's needs for spawning and rearing to reach a maturity level fit for the ocean. From 2008 to 2012, the placement totaled 85,880 short tons (77.91 kt) of gravel. The gravel will increase the number of fish redds, spawning nests, along the American River, which will decrease egg retention, and increase birth and survivorship rate. The project also included the introduction of small islands, loose woody debris, and larger boulders to advance

5680-479: The sea by a narrow mouth. Since the level of the basin is always at mean sea level, the flood in the mouth starts at half tide, and its velocity is at its greatest at the time of high water, with the strongest ebb occurring conversely at low water. For scuba divers , the absence of a flow means that less effort is required to swim and there is less likelihood of drifting away from a vessel or shore. Slack water following high tide can improve underwater visibility , as

5760-412: The section of the river that flows through Sacramento County. Slack water Slack tide or slack water is the short period in a body of tidal water when the water is completely unstressed, and there is no movement either way in the tidal stream. It occurs before the direction of the tidal stream reverses. Slack water can be estimated using a tidal atlas or the tidal diamond information on

5840-582: The source of the North Fork on the south face of Granite Chief , between the summit and Emigrant Pass. It is characterized by somewhat broader steep canyons interspersed with reservoirs , waterfalls, and quiet riparian areas. The Middle Fork is used extensively for both motorized and non-motorized recreation, including fishing, white water rafting , bicycling (mountain and road), horseback riding, trail running and hiking. It contains areas used for hydroelectric generation, mining , and agricultural timber cultivation and harvesting. The Middle Fork features part of

5920-453: The vast majority of wetlands have been converted to agriculture or urban areas. Most of the remaining wetland, riparian and aquatic ecosystems are restricted to the narrow corridor along the American River. There is an abundance of flora and fauna found at the American River that creates an immensely bio diverse ecosystem. Native plants along the American River Parkway are adapted to a Mediterranean climate, are drought tolerant, and help support

6000-545: The weir can handle flows up to 5,000 cubic feet per second, and must sometimes be removed before sufficient numbers of adult Chinook salmon have arrived at the fish ladder. The most recent significant flood to damage the weir foundation and river embankment next to the Hatchery occurred in January 1997, prompting major repairs until 1999. In response, the Bureau of Reclamation asked the NMFS (National Marine Fisheries Service) about

6080-593: The weir, defeating its purpose and preventing the salmon from reaching the Hatchery's fish ladder. Flow reductions during the repair period lasted around five to nine days. These disruptions negatively affected steelhead in the area by temporarily reducing available habitat space, leading to less cover from predators and increased population density of steelhead, instigating increased predation and disease susceptibility. Additionally, lowering flows raises water temperatures while decreasing dissolved oxygen levels, further worsening aquatic living conditions. The racks and pickets of

6160-468: The years. Floods would cause the weir to continually degrade and constant flow reductions would continue, therefore not fulfilling Reclamation's goals. The EIS/EIR determined Alternative 1C to be the preferred approach. 1C's implementation will be broken up into three parts. First, the fish passageway extension will be built. Second, operations and assessments of the passageway will take place before removing outdated facilities. Lastly, although not necessary,

6240-683: Was built in 1955 as a principal part of the Central Valley Project by the Army Corps of Engineers, and is operated by the Bureau of Reclamation. The concrete and earth embankment structure is more than 5 miles (8.0 km) long and creates Folsom Lake , impounding 1.1 million acre-feet (1.4 km ) of water when full. The dam is a multipurpose facility that acts as a reservoir for flood control, irrigation, domestic and industrial use, as well as hydroelectric power generation, recreation, and fish and wildlife habitat. Nimbus Dam

6320-550: Was established as part of a greater habitat mitigation network. Currently the majority of Chinook fry from the hatchery are released in the American River near the hatchery to encourage thorough imprinting on their home river, which is thought to improve their odds of returning to the correct river as adults and to reduce straying. About one quarter of the fish are trucked further down to the Delta in order to avoid predation from larger fish, such as bass, and other wildlife. The Hatchery

6400-487: Was used to drive grist mills . Gold miners dredged the riverbed and constructed diversion dams for hydraulic mining . Mining activity caused sediment and mercury waste to accumulate in the rivers. The Natoma Company completed its Folsom Powerhouse in 1895 and began delivering power 22 miles (35 km) away to the city of Sacramento to power a streetcar system. Major flooding of the Sacramento area led to calls for

#174825