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Articles 2581 - 2610 of 5272

Full-Text Articles in Hydrology

A Functional Visual System In The Cave Beetle Ptomaphagus Hirtus, Markus Friedrich, Rui Chen, Elke K. Buschbeck, Stewart Peck Feb 2013

A Functional Visual System In The Cave Beetle Ptomaphagus Hirtus, Markus Friedrich, Rui Chen, Elke K. Buschbeck, Stewart Peck

Mammoth Cave Research Symposia

Cave species exhibit a suite of dramatic differences in comparison to their surface living relatives, commonly referred to as troglomorphy (Christiansen 2005). One hallmark feature of troglomorphy is the severe reduction or complete loss of eyes and functional vision. The two most abundant cave beetle species in Mammoth cave, the 2-3 mm small carrion beetle Ptomaphagus hirtus (Packard 1888; Peck 1973; Peck 1975; Tellkampf 1844) and the 6-8 mm long predatory ground beetle Neaphaenops tellkampfii are good examples of this (Barr 1979). P. hirtus tends to hide in crevices and usually goes unnoted to the regular visitor of Mammoth cave. …


Disjunct Eastern Hemlock Populations Of The Central Hardwood Forests: Ancient Relicts Or Recent Long Distance Dispersal Events?, F. Collin Hobbs, Keith Clay Feb 2013

Disjunct Eastern Hemlock Populations Of The Central Hardwood Forests: Ancient Relicts Or Recent Long Distance Dispersal Events?, F. Collin Hobbs, Keith Clay

Mammoth Cave Research Symposia

Eastern hemlock (Tsuga canadensis) is an evergreen conifer with a contiguous distribution extending from the southern Appalachian Mountains north to Nova Scotia and west across the Great Lakes region. Eastern hemlock is threatened with extirpation from much of this range by an introduced pest, the hemlock woolly adelgid (Orwig et al. 2002). In addition to the contiguous distribution, many small, isolated populations are located within the central hardwood forest region of Kentucky, Indiana, and Ohio (Braun 1928, Potzger and Friesner 1937, Van Stockum 1979). These disjunct populations form clearly delineated, often monospecific stands associated with unique natural features such as …


Breeding Bird Survey Summary From Mammoth Cave National Park, 1995 - 2012, Steve Kistler Feb 2013

Breeding Bird Survey Summary From Mammoth Cave National Park, 1995 - 2012, Steve Kistler

Mammoth Cave Research Symposia

Breeding bird surveys are used by ornithologists to study the variations in bird populations across the United States and Canada. Initiated in 1966, the surveys were originally created by Chandler Robbins and colleagues to study the effects of pesticide use on bird populations.

Today, these data are used to monitor changes in avian populations due to habitat loss, habitat fragmentation, land-use changes, and chemical contamination. The administration of these surveys is jointly run by the US Geological Survey and the Canadian Wildlife Service. Almost fifty years of continuous surveying also provides excellent baseline data which can be used to determine …


Landscape Genetics Of The Marbled Salamander, Ambystoma Opacum, In A Nationally Protected Park, Kevin Tewell, Jarrett Johnson Feb 2013

Landscape Genetics Of The Marbled Salamander, Ambystoma Opacum, In A Nationally Protected Park, Kevin Tewell, Jarrett Johnson

Mammoth Cave Research Symposia

Landscape features may influence the patterns of migration and dispersal of amphibian species and create genetic structure. A primary goal of landscape genetics is to analyze these influences in order to make more informed management decisions. We sampled larvae from 50 breeding ponds within the boundaries of Mammoth Cave National Park and genotyped 12 individuals per pond at 10 microsatellite loci to estimate gene fl ow between ponds. We used GIS layers of habitat types to conduct a least-cost path analysis and determine the relative cost of movement through each habitat type. We were interested in answering two questions: does …


Evaluating Interactions Between River Otters And Muskrats At Bridge Crossings In Kentucky, Ryan Williamson, Joseph Clark Feb 2013

Evaluating Interactions Between River Otters And Muskrats At Bridge Crossings In Kentucky, Ryan Williamson, Joseph Clark

Mammoth Cave Research Symposia

Muskrats (Ondatra zibethicus) prey on freshwater mussels in the Green River within Mammoth Cave National Park (MACA), many species of which are threatened or endangered. Reportedly, muskrat populations have been reduced in some streams where North American river otters (Lontra canadensis) were reintroduced and it has been suggested that river otter reintroduction at MACA might help conserve endangered mussels. To test that idea, we used occupancy estimation methods to evaluate the ecological relationship between muskrats and otters by collecting presence/absence data based on field sign found at bridge crossings in eastern and central Kentucky. Mean detection (p) and occupancy probabilities …


Mammoth Cave In Poetry: Davis Mccombs’ Ultima Thule, Judith Hatchett Feb 2013

Mammoth Cave In Poetry: Davis Mccombs’ Ultima Thule, Judith Hatchett

Mammoth Cave Research Symposia

Davis McCombs, former Mammoth Cave park ranger, received the Yale Younger Poets Award for Ultima Thule, his collection of poems based on his experiences in and with Mammoth Cave, not only of his actual experiences as ranger and cave explorer, but also of the history of the cave, including poems in the voice of Stephen Bishop, cave explorer, cave guide, and also a slave. The detail of McCombs’ examination produces what poet W.S. Merwin called “a grave, attentive holding of a light.” In a sense, his poetry illuminates the cave the way ancient torches and modern lighting have done. This …


First Underground Photograph Taken In America, Wm. Gross Magee Feb 2013

First Underground Photograph Taken In America, Wm. Gross Magee

Mammoth Cave Research Symposia

The presentation covers the work of Charles Waldack in Mammoth Cave. Waldack took the first underground photographs in America. He was the pioneer of using magnesium as a light source for cave photography. It explores the who, why, when, where and how of his images in the cave. It covers the recreation of his stereo views in the cave showing the same views taken nearly 150 years apart.


Archaeological Investigations For Proposed Trail Rehabilitation Within Mammoth Cave, Steven R. Ahler, George M. Crothers Feb 2013

Archaeological Investigations For Proposed Trail Rehabilitation Within Mammoth Cave, Steven R. Ahler, George M. Crothers

Mammoth Cave Research Symposia

In 2008, staff from the University of Kentucky Program for Archaeological Research (UK-PAR) and the Illinois State Museum Society (ISMS) conducted archaeological and paleontological investigations at Mammoth Cave National Park in advance of proposed rehabilitation of 40,499 linear feet of selected trail segments within Mammoth Cave. This presentation focuses on the results of archaeological investigations conducted within Mammoth Cave and is confined to discussion of the prehistoric materials. These materials were confined to the upper and lower passages of the Historic Tour, the Lantern Tour, and Gothic Avenue trails


The History And Conservation Of Saltpeter Works In Mammoth Cave, Kentucky, George M. Crothers, Christina A. Pappas, Christian D. Mittendorf Feb 2013

The History And Conservation Of Saltpeter Works In Mammoth Cave, Kentucky, George M. Crothers, Christina A. Pappas, Christian D. Mittendorf

Mammoth Cave Research Symposia

Remains of the saltpeter mining operation in Mammoth Cave are a significant feature of several cave tours and figure prominently in the history of cave use. We undertook a comprehensive review of existing historical descriptions and recent archaeological investigations to construct the most reasonable account of how the saltpeter operation worked and assess its current conditions. At least three types of saltpeter vats were constructed in the cave reflecting an increase in the size of the operation and efficiency of processing sediments over time. Remains of three pump towers are also found in the cave in various states of preservation. …


The Mammoth Cave Mushroom Company: A Brief History Of A Short-Lived Venture, Katie Algeo Feb 2013

The Mammoth Cave Mushroom Company: A Brief History Of A Short-Lived Venture, Katie Algeo

Mammoth Cave Research Symposia

The Mammoth Cave Mushroom Company was formed in August 1881 during a particularly contentious period of family struggle for control of the cave, its resources, and tourism operations. This paper documents the history of the company from original company records and family letters. It places the Mammoth Cave operation within the larger historical context of mushroom production in caves as possibly the first such operation in the United States. It traces developments at the cave during the fall of 1881 as Anthony Muzarelli oversaw preparation of mushroom beds and supporting infrastructure and identifies sources of tension between the new mushroom …


Mammoth Cave National Park's 10th Research Symposium: Celebrating Diversity Of Research In The Mammoth Cave Region, Shannon Trimboli ,Editor Feb 2013

Mammoth Cave National Park's 10th Research Symposium: Celebrating Diversity Of Research In The Mammoth Cave Region, Shannon Trimboli ,Editor

Mammoth Cave Research Symposia

No abstract provided.


U.S. Drought Monitor, February 12, 2013, Michael J. Brewer, Liz Love-Brotak Feb 2013

U.S. Drought Monitor, February 12, 2013, Michael J. Brewer, Liz Love-Brotak

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for February 12, 2013 (2/12/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.


Understanding Greenland Ice Sheet Hydrology Using An Integrated Multi-Scale Approach, A. K. Rennermalm, S. E. Moustafa, J. Mioduszewski, V. W. Chu, R. R. Forster, B. Hagedorn, Joel T. Harper, T. L. Mote, D. A. Robinson, C. A. Shuman, L. C. Smith, M. Tedesco Feb 2013

Understanding Greenland Ice Sheet Hydrology Using An Integrated Multi-Scale Approach, A. K. Rennermalm, S. E. Moustafa, J. Mioduszewski, V. W. Chu, R. R. Forster, B. Hagedorn, Joel T. Harper, T. L. Mote, D. A. Robinson, C. A. Shuman, L. C. Smith, M. Tedesco

Geosciences Faculty Publications

Improved understanding of Greenland ice sheet hydrology is critically important for assessing its impact on current and future ice sheet dynamics and global sea level rise. This has motivated the collection and integration of in situ observations, model development, and remote sensing efforts to quantify meltwater production, as well as its phase changes, transport, and export. Particularly urgent is a better understanding of albedo feedbacks leading to enhanced surface melt, potential positive feedbacks between ice sheet hydrology and dynamics, and meltwater retention in firn. These processes are not isolated, but must be understood as part of a continuum of processes …


U.S. Drought Monitor, February 5, 2013, Michael J. Brewer, Liz Love-Brotak Feb 2013

U.S. Drought Monitor, February 5, 2013, Michael J. Brewer, Liz Love-Brotak

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for February 5, 2013 (2/5/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.


Neotectonic Evolution Of Grand Canyon : Interaction Between Volcanism, River Incision, Epeirogenic Uplift, And Faulting, Ryan Crow Jan 2013

Neotectonic Evolution Of Grand Canyon : Interaction Between Volcanism, River Incision, Epeirogenic Uplift, And Faulting, Ryan Crow

Earth and Planetary Sciences ETDs

This thesis focuses on the effects of volcanism, river incision, epeirogenic uplift, and faulting on the landscape evolution of the Grand Canyon region. In the first chapter the migration of increasingly asthenospheric basaltic volcanism is used to constrain lithospheric modification of the Colorado Plateau margins. Buoyancy modification of the upper mantle, driven by the upwelling, is a likely driver for recent uplift of the area. In the second chapter, correlation between oversteepened rivers and areas of high-velocity upper mantle is used to show that recent and ongoing mantle-driven uplift is modulating the surface along the western margin of the Colorado …


U.S. Drought Monitor, January 29, 2013, Mark D. Svoboda Jan 2013

U.S. Drought Monitor, January 29, 2013, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for January 29, 2013 (1/29/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.


An Intercomparison Of Drought Indicators Based On Thermal Remote Sensing And Nldas-2 Simulations With U.S. Drought Monitor Classifications, Martha C. Anderson, Christopher Hain, Jason Otkin, Xiwu Zhan, Kingtse Mo, Mark Svoboda, Brian Wardlow, Agustin Pimstein Jan 2013

An Intercomparison Of Drought Indicators Based On Thermal Remote Sensing And Nldas-2 Simulations With U.S. Drought Monitor Classifications, Martha C. Anderson, Christopher Hain, Jason Otkin, Xiwu Zhan, Kingtse Mo, Mark Svoboda, Brian Wardlow, Agustin Pimstein

National Drought Mitigation Center: Faculty Publications

Comparison of multiple hydrologic indicators, derived from independent data sources and modeling approaches, may improve confidence in signals of emerging drought, particularly during periods of rapid onset. This paper compares the evaporative stress index (ESI)—a diagnostic fast-response indicator describing evapotranspiration (ET) deficits derived within a thermal remote sensing energy balance framework—with prognostic estimates of soil moisture (SM), ET, and runoff anomalies generated with the North American Land Data Assimilation System (NLDAS). Widely used empirical indices based on thermal remote sensing [vegetation health index (VHI)] and precipitation percentiles [standardized precipitation index (SPI)] were also included to assess relative performance. Spatial and …


U.S. Drought Monitor, January 22, 2013, Mark D. Svoboda Jan 2013

U.S. Drought Monitor, January 22, 2013, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for January 22, 2013 (1/22/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.


U.S. Drought Monitor, January 15, 2013, David Simeral Jan 2013

U.S. Drought Monitor, January 15, 2013, David Simeral

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for January 15, 2013 (1/15/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.


U.S. Drought Monitor, January 8, 2013, David Simeral Jan 2013

U.S. Drought Monitor, January 8, 2013, David Simeral

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for January 8, 2013 (1/8/13) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Hay, Cattle, Winter wheat.


Tackling Change: Future-Proofing Water, Agriculture, And Food Security In An Era Of Climate Uncertainty, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre Jan 2013

Tackling Change: Future-Proofing Water, Agriculture, And Food Security In An Era Of Climate Uncertainty, Peter G. Mccornick, Vladimir Smakhtin, Luna Bharati, Robyn Johnston, Matthew Mccartney, Fraser Sugden, Floriane Clement, Beverly Mcintyre

Daugherty Water for Food Global Institute: Faculty Publications

In 1950 the global population was just over 2.5 billion. Now, in 2013, it is around 7 billion. Although population growth is slowing, the world is projected to have around 9.6 billion inhabitants by 2050. Most of the population increase will be in developing countries where food is often scarce, and land and water are under pressure. To feed the global population in 2050 the world will have to produce more food without significantly expanding the area of cultivated land and, because of competition between a greater number of water users, with less freshwater. On top of land and water …


Modeling Urban Hydrology: A Comparison Of New Urbanist And Traditional Neighborhood Design Surface Runoff, C. Andrew Day, Keith A. Bremer Ph.D. Jan 2013

Modeling Urban Hydrology: A Comparison Of New Urbanist And Traditional Neighborhood Design Surface Runoff, C. Andrew Day, Keith A. Bremer Ph.D.

Geosciences Faculty Publications

Urban development affects the amount of potential surface runoff generated during storms by changing the amount of impervious cover across the landscape. However, the degree of surface runoff alteration depends on the type of urban development in place. New urbanist developments are designed with higher densities and encourage a diversity of land uses, while traditional neighborhood developments have a monotone land use pattern with medium-to- low densities. Two neighborhoods within the city of Austin, Texas- Mueller, a new urbanist development, and Circle C Ranch, a traditional neighborhood development- were used to study the effect of development type on potential surface …


A Comprehensive Approach To Alluvial Fan Management: A Case Study Of Travertine Point, Coachella Valley, Jason Joseph Thomas Jan 2013

A Comprehensive Approach To Alluvial Fan Management: A Case Study Of Travertine Point, Coachella Valley, Jason Joseph Thomas

Theses Digitization Project

The purpose of this project is to make a contribution towards improving the sustainability of developments (master plan communities) on alluvial fans. To do this, the authors intent is to further the goals of the Integrated Approach for Sustainable Development on Alluvial Fans Task Force.


Understanding And Managing Karst Water Resources In Belize: Case Studies Of Both Past And Present In A Changing Climate, Jason S. Polk, Leslie North, Ben Miller, Jonathan Oglesby, Kegan Mcclanahan, Lowell Neeper, Aaron Holland, Bernie Strenecky Jan 2013

Understanding And Managing Karst Water Resources In Belize: Case Studies Of Both Past And Present In A Changing Climate, Jason S. Polk, Leslie North, Ben Miller, Jonathan Oglesby, Kegan Mcclanahan, Lowell Neeper, Aaron Holland, Bernie Strenecky

Earth, Environmental, and Atmospheric Sciences Faculty Publications

Belize is a developing country that faces water resource issues in the forms of both quality and quantity, stemming from a long history of environmental stress and population threats, from the ancient Maya to present. Belize’s karst landscape, which comprises a large part of the country from the coast to the Maya Mountains, is characterized by springs, caves, sinkholes, and aquifers systems formed from the dissolution of carbonate (limestone, dolomite) rock. This research presents several different case studies, spanning from the ancient Maya and issues with drought to modern communities that rely on groundwater resources quickly being depleted. Past drought …


Estimating Greenhouse Gas Emissions From A Waste Lagoon, Arturo I. Quintanar, Rezaul Mamood, Nanh Lovanh, Justin M. Rawley, Evi Becerra-Acosta, John H. Loughrin Jan 2013

Estimating Greenhouse Gas Emissions From A Waste Lagoon, Arturo I. Quintanar, Rezaul Mamood, Nanh Lovanh, Justin M. Rawley, Evi Becerra-Acosta, John H. Loughrin

High Plains Regional Climate Center: Staff Publications

A cost-effective approach was used to investigate the relationship between emission of the greenhouse gases (GHG), namely, CO2, CH4, and N2O and energy fluxes from a swine waste lagoon. Energy fluxes were calculated using the Penman method. The energy fluxes showed a diurnal pattern as expected of such fluxes. We found that air temperature and latent energy, lagoon surface temperature and solar radiation, as well as air temperature and wind speed can be used to predict for CO2, CH4, and N2O emissions, respectively. Comparison of observed and predicted …


Regional Climate Trends And Scenarios For The U.S. National Climate Assessment Part 4. Climate Of The U.S. Great Plains, Kenneth E. Kunkel, Laura E. Stevens, Scott E. Stevens, Liqiang Sun, Emily Janssen, Donald Wuebbles, Michael C. Kruk, Devin Thomas, Martha Shulski, Natalie A. Umphlett, Kenneth G. Hubbard, Kevin Robbins, Luigi Romolo, Adnan Akyuz, Tapan B. Pathak, Tony R. Bergantino, J. Greg Dobson Jan 2013

Regional Climate Trends And Scenarios For The U.S. National Climate Assessment Part 4. Climate Of The U.S. Great Plains, Kenneth E. Kunkel, Laura E. Stevens, Scott E. Stevens, Liqiang Sun, Emily Janssen, Donald Wuebbles, Michael C. Kruk, Devin Thomas, Martha Shulski, Natalie A. Umphlett, Kenneth G. Hubbard, Kevin Robbins, Luigi Romolo, Adnan Akyuz, Tapan B. Pathak, Tony R. Bergantino, J. Greg Dobson

High Plains Regional Climate Center: Staff Publications

This document is one of series of regional climate descriptions designed to provide input that can be used in the development of the National Climate Assessment (NCA). As part of a sustained assessment approach, it is intended that these documents will be updated as new and well-vetted model results are available and as new climate scenario needs become clear. It is also hoped that these documents (and associated data and resources) are of direct benefit to decision makers and communities seeking to use this information in developing adaptation plans.

There are nine reports in this series, one each for eight …


Emergent Sandbar Dynamics In The Lower Platte River In Eastern Nebraska: Methods And Results Of Pilot Study, 2011, Jason S. Alexander, Devin M. Schultze, Ronald B. Zelt Jan 2013

Emergent Sandbar Dynamics In The Lower Platte River In Eastern Nebraska: Methods And Results Of Pilot Study, 2011, Jason S. Alexander, Devin M. Schultze, Ronald B. Zelt

United States Geological Survey: Water Reports and Publications

The lower Platte River corridor provides important habitats for two State- and federally listed bird species: the interior least tern (terns; Sternula antillarum athallassos) and the piping plover (plovers; Charadrius melodus). However, many of the natural morphological and hydrological characteristics of the Platte River have been altered substantially by water development, channelization, hydropower operations, and invasive vegetation encroachment, which have decreased the abundance of high-quality nesting and foraging habitat for terns and plovers. The lower Platte River (LPR), defined as 103 miles (mi) of the Platte River between its confluence with the Loup River and its confluence with the Missouri …


Comparison Of Water Consumption In Two Riparian Vegetation Communities Along The Central Platte River, Nebraska, 2008–09 And 2011, Brent M. Hall, David L. Rus Jan 2013

Comparison Of Water Consumption In Two Riparian Vegetation Communities Along The Central Platte River, Nebraska, 2008–09 And 2011, Brent M. Hall, David L. Rus

United States Geological Survey: Water Reports and Publications

The Platte River is a vital natural resource for the people, plants, and animals of Nebraska. A recent study quantified water use by riparian woodlands along central reaches of the Platte River, Nebraska, finding that water use was mainly regulated below maximum predicted levels. A comparative study was launched through a cooperative partnership between the United States Geological Survey (USGS), the Central Platte Natural Resources District, the Nebraska Department of Natural Resources, and the Nebraska Environmental Trust to compare water use of a riparian woodland with that of a grazed riparian grassland along the central Platte River. This report describes …


Hydrographic Surveys Of The Missouri And Yellowstone Rivers At Selected Bridges And Through Bismarck, North Dakota, During The 2011 Flood, Brenda K. Densmore, Kellan R. Strauch, Benjamin J. Dietsch Jan 2013

Hydrographic Surveys Of The Missouri And Yellowstone Rivers At Selected Bridges And Through Bismarck, North Dakota, During The 2011 Flood, Brenda K. Densmore, Kellan R. Strauch, Benjamin J. Dietsch

United States Geological Survey: Water Reports and Publications

The United States Geological Survey (USGS), in cooperation with the North Dakota Department of Transportation and the North Dakota State Water Commission, completed hydrographic surveys at six Missouri River bridges and one Yellowstone River bridge during the 2011 flood of the Missouri River system. Bridges surveyed are located near the cities of Cartwright, Buford, Williston, Washburn, and Bismarck, N. Dak. The river in the vicinity of the bridges and the channel through the city of Bismarck, N. Dak., were surveyed. The hydrographic surveys were conducted using a high-resolution multibeam echosounder (MBES), the RESON SeaBatTM 7125, during June 6–9 and June …


Hydrographic Surveys Of Four Narrows Within The Namakan Reservoir System, Voyageurs National Park, Minnesota, 2011, Brenda K. Densmore, Kellan R. Strauch, Jeffrey R. Kiegweid Jan 2013

Hydrographic Surveys Of Four Narrows Within The Namakan Reservoir System, Voyageurs National Park, Minnesota, 2011, Brenda K. Densmore, Kellan R. Strauch, Jeffrey R. Kiegweid

United States Geological Survey: Water Reports and Publications

The United States Geological Survey (USGS) performed multibeam echosounder hydrographic surveys of four narrows in the Namakan reservoir system in August 2011, in cooperation with the International Joint Commission and Environment Canada. The data-collection effort was completed to provide updated and detailed hydrographic data to Environment Canada for inclusion in a Hydrologic Engineering Centers River Analysis System hydraulic model. The Namakan reservoir system is composed of Namakan, Kabetogama, Sand Point, Crane, and Little Vermilion Lakes. Water elevations in the Namakan reservoir system are regulated according to rule curves, or guidelines for water-level management based on the time of year, established …