NU Water-Related Research in District 34

The list below shows water-related research being conducted within your district or that affects your district. They are sorted by water topic, then by primary contact's last name.

Displaying 37 records found for District 34


Topic Climate
Project's Primary Contact Information
Name Irmak, Suat
Unit Biological Systems Engineering
Email sirmak2@unl.edu
Phone 402-472-4865
Web Page http://bse.unl.edu/sirmak2
Project Information
Title Dynamics of Climate Change in Central Platte Valley, Nebraska, as Indicated by Agro-meteorological Indices over 116 years (1893-2008): Preliminary Analyses
Other(s) Kabenge, Isa Mutiibwa, Denis 
Description

It has been established with a degree of confidence that the temperature of the earth’s atmosphere has increased by about 0.3 to 0.6 degrees C in the late 19th century (IPCC, 1997). Global warming can have substantial impact on agricultural production, water resources, and their interactions, by influencing microclimatic variables that drive plant physiological functions, such as surface air temperature, solar radiation, humidity, wind speed, rainfall frequency and amount, as well as hydrological balances, including evapotranspiration. Knowledge and analyses of long-term historical trends in agro-meteorological and hydrological parameters can aid in water resources design, planning, and man-agement. Historical trends in these variables can also help to relate agro-ecosystem production to climate change. We assessed the long-term trends in climatic variables. We quantified reference evapo-transpiration from solar and net radiation, vapor pressure deficit, wind speed, relative humidity, and air temperature from 1893 to 2008 using measured and estimated climatic data. Both alfalfa-reference and grass-reference evapotranspiration values were computed on a daily time step. We present historical trends in air temperature, relative humidity, preci-pitation, solar radiation, and evapotranspiration from 116 years of climatic observations and modeling results in the Central Platte Valley, Nebraska.

Conclusions from this project are:

  • Missing long-term climatic variables from 1893 to 1986 were reliably estimated for reference ET calculations.
  • Annual total rainfall amount showed an increasing trend over 116 years.
  • Both grass and alfalfa-reference ET fluctuated from year to year, but slightly decreased over the years.
  • Solar radiation slightly decreased due to increased rainfall/cloud cover.
  • Average vapour pressure deficit (VPD) did not change considerably.
  • Aridity index trend indicates a general tendency for Central City, NE area to shift toward more humid conditions, more so in the last 10 years.
Project Support
Project Website
Report
Current Status Completed
Topic Crop Nutrient Use
Project's Primary Contact Information
Name Ferguson, Richard
Unit Agronomy and Horticulture
Email rferguson1@unl.edu
Phone 402-472-1144
Web Page http://agronomy.unl.edu/ferguson
Project Information
Title Nutrient Management to Benefit Crops and Protect Water Quality
Other(s) Dean Krull, West Central Research and Extension Center, dkrull1@unl.edu 
Description

Ferguson is doing several projects with sites in Merrick and Hamilton counties focused on managing nitrogen applications to both benefit the crop and protect water quality.

  • The Impact of Controlled Release Urea Formulation on Nitrate Leaching Below the Root Zone of Irrigated Corn - Merrick County. This study is measuring nitrate leaching throughout the growing season on a coarse-textured soil planted to irrigated corn. Treatments include different nitrogen fertilizer sources and rates.
  • Relay Cropping Effects on Nitrate Accumulation in the Root Zone - Merrick County. This study evaluates the cumulative effect of the seed corn/winter wheat/relay-cropped soybean on nitrate accumulation in the root zone over the two year cropping system cycle.
  • In-Season Nitrogen Management Using Active Crop Canopy Sensors - Hamilton and Merrick counties. This series of studies on multiple crops (winter wheat, commercial corn, seed corn) at multiple sites investigates the use of active crop canopy sensors to control nitrogen fertilizer application during the growing season, using the crop to detect soil N supply rather than predicting soil N supply through soil sampling.
  • The Use of Polymers to Inhibit Nitrate Movement Below the Root Zone of Irrigated Corn - Merrick County. This study investigates the potential of various soil-applied polymers to retain nitrate in the root zone, preventing it from leaching into the vadose zone and eventually groundwater.
Project Support Central Platte NRD, Department of Agriculture, Agrium Inc., Georgia-Pacific, Dow AgroSciences, Monsanto Co., Nebraska Corn Board, Nebraska Environmental Trust
Project Website http://soilfertility.unl.edu/index.html
Report
Current Status Underway
Topic Crop Water Use
Project's Primary Contact Information
Name Cassman, Ken
Unit Agronomy and Horticulture
Email kcassman1@unl.edu
Phone 402-472-5554
Web Page http://agronomy.unl.edu/cassman
Project Information
Title Real-time Decision Support System for Deficit Irrigation - Hybrid-Maize
Other(s)  
Description

Hybrid-Maize is a computer program that simulates the growth of a corn crop under non-limiting or water-limited (rainfed or irrigated) conditions based on daily weather data. Specifically, it allows the user to:

  • assess the overall site yield potential and its variability based on historical weather data
  • evaluate changes in attainable yield using different combinations of planting date, hybrid maturity, and plant density
  • explore options for optimal irrigation management
  • conduct in-season simulations to evaluate actual growth up to the current date based on real-time weather data, and to forecast final yield scenarios based on historical weather data for the remainder of the growing season

Hybrid-Maize does NOT allow assessment of different options for nutrient management nor does it account for yield losses due to weeds, insects, diseases, lodging, and other stresses. Hybrid-Maize has been evaluated primarily in rainfed and irrigated maize systems of the U.S. Corn Belt. Caution should be exercised when applying this model to other environments as this may require changes in some of the default model parameters.

This project will develop a similar tool for irrigation scheduling for Nebraska soybean producers, and a real-time decision support system for deficit irrigation on corn, both based upon the Hybrid-Maize model. These tools will assist producers who have limited irrigation water supplies to optimize irrigation scheduling in real time for maximum yields, in particular during water-short years.

Project Support Nebraska Natural Resources Conservation Service, Nebraska Soybean Board
Project Website http://hybridmaize.unl.edu/
Report
Current Status Continuing - Software Available
Topic Crop Water Use
Project's Primary Contact Information
Name Irmak, Suat
Unit Biological Systems Engineering
Email sirmak2@unl.edu
Phone 402-472-4865
Web Page http://bse.unl.edu/sirmak2
Project Information
Title Mapping Spatial Distribution of Evapotranspiration and Other Energy Fluxes for Key Vegetation Surfaces
Other(s) Ayse Irmak, School of Natural Resources, airmak2@unl.edu; Shashi Verma, School of Natural Resources, sverma1@unl.edu; Derrel Martin, Biological Systems Engineering, dmartin2@unl.edu 
Description Efficient use of water resources in semi-arid agro-ecosystems of Nebraska is an important issue because of the rapid depletion of freshwater resources and drought conditions, and degradation of groundwater quality in recent years. Proper planning and management, and related policy decisions of water resources require accurate quantification of evapotranspiration (ET). An extensive field campaign has been initiated with the Central Platte Natural Resources District and UNL in the Central Platte River Valley to measure ET and other surface energy fluxes for various vegetation surfaces. The vegetation surfaces include, center pivot-irrigated grassland, rainfed grassland, rainfed winter wheat, center pivot-irrigated alfalfa, Phragmites australis-dominated cottonwood and willow stand plant community, irrigated maize, irrigated soybeans. A deluxe version of Bowen ratio energy balance systems are being used to measure ET and other surface energy balance components, soil moisture, and plant physiological parameters in each research site.
Project Support Central Platte Natural Resources District
Project Website
Report
Current Status Underway
Topic Crop Water Use
Project's Primary Contact Information
Name Irmak, Suat
Unit Biological Systems Engineering
Email sirmak2@unl.edu
Phone 402-472-4865
Web Page http://bse.unl.edu/sirmak2
Project Information
Title A Decision Support Tool to Increase Energy and Crop Water Use Efficiency for Corn and Soybean Production
Description

Energy costs coupled with limitations in water availability are threatening the sustainability of irrigation in the state. Energy costs for irrigation rose almost 100 percent for typical Nebraska irrigators from the spring of 2003 to the summer of 2006 and continue to rise sharply. The rising cost of fuel and the limited availability of water make producing maximum crop yield with minimal input imperative.

Nebraska growers need scientifically based and practical management strategies that can aid them in their decision-making process to enhance crop water-use efficiency and reduce energy use to achieve maximum profitability. Growers are looking for answers on how to make a maximum use of limited irrigation water and how to manage irrigation water to reduce pumping cost.

Crop simulation models with the capability of "real-time" assessment of crop and soil water status and yield prediction based on historical climate data represent a powerful new tool to help improve irrigation decisions and increase water-use efficiency especially for situations where the amount of available water supply is less than the full requirement for maximum crop yield. This project validates and demonstrates a decision-support tool for a real-time irrigation scheduling period, and releases the new tool as a software program for use by crop producers, crop consultants, and industry professionals. This tool will be used to assess energy requirement for different irrigation regimes to aid growers and state and federal agencies to make better-informed management decisions.

Project Support Upper Big Blue Natural Resources District, Gard Fund
Project Website
Report
Current Status Underway
Topic Crop Water Use
Project's Primary Contact Information
Name Irmak, Suat
Unit Biological Systems Engineering
Email sirmak2@unl.edu
Phone 402-472-4865
Web Page http://bse.unl.edu/sirmak2
Project Information
Title Nebraska Agricultural Water Management Demonstration Network
Other(s) Gary Zoubek, York County Extension, gzoubek@unl.edu 
Description

The Nebraska Agricultural Water Management Demonstration Network (NAWMDN) encourages the adoption of newer technologies that will enable farmers to use water and energy resources associated with irrigated crop production efficiently. NAWMDN launched in 2005 and started with 20 growers from south central Nebraska who joined the Network as collaborators. In 2008 an online tool named ETgage was added to enable participation by growers throughout Nebraska.

The NAWMDN ETgage project is one part of a system for testing cutting-edge technologies and creating a network with growers, UNL Extension, NRDs, NRCS, and crop consultants, and other interested partners, that will enable the adoption of water and energy conservation practices. The simplicity of the use and interpretation of the ETgage data, as well as its economic feasibility, makes it easy for farmers to monitor crop water use for effective irrigation management. In this project ETgages are used to estimate crop water use, and Watermark sensors are used to measure soil moisture to determine irrigation timing and amount. Each year, NAWMDN team members organize educational meetings during the growing season and over the winter to implement the project, teach participants how to use the ETgage and Watermark sensors for irrigation management, review the results, set goals, and obtain grower feedback. This project has been reported at local, regional, and national meetings.

In 2005, there were 18 demonstration sites. Some of the ETgage and Watermark sensors were read by growers and some were read weekly by Network core members. In 2006, the second year of the project, there were more than 50 demonstration sites. In 2007 more than 125 cooperators in nine NRDs and 22 counties were involved. In the fall of 2007, 89 producers involved in the NAWMDN were surveyed; of those 56% responding, the estimated corn water savings varied from 0-7.5" with an average savings of 2.6," while soybeans water savings varied from 0-4.8" with an average of 2.1." Using 2007 diesel prices, this resulted in total energy savings of $2,808,000 and $2,269,800 for corn or soybeans over 117,000 acres.

In 2008 over 300 active participants from 25 counties in 9 of Nebraska's 23 NRDs. An interactive web site was also created to inform growers and other clients about the network and to educate producers and industry professionals about using these two tools along with crop stage of growth information to make irrigation management decisions. This interactive web site has engaged the cooperating producers and enhanced learning. The site consists of a map of Nebraska's 93 counties on which producers can select specific counties to find a Google gps map with ETgauge locations marked. Producers can click on specific sites to see the weekly reference evapoptranspiration (ET) reported by producers. The site also includes information about the NAWMDN and how to use the various tools.

For detailed information, see Nebraska Agricultural Water Management Demonstration Network: Integrating Research and Extension/Outreach.

Project Support Partners include personnel from 19 extension offices, the Little Blue NRD, the Upper Big Blue NRD, Nebraska Association of Resources Districts, Nebraska Natural Resources Conservation Service, South Central Agricultural Laboratory, and the Central Nebraska Public Power and Irrigation District.
Project Website http://water.unl.edu/cropswater/nawmdn
Report
Current Status Continuing
Topic Crop Water Use
Project's Primary Contact Information
Name Martin, Derrel
Unit Biological Systems Engineering
Email dmartin1@unl.edu
Phone 402-472-1586
Web Page http://bse.unl.edu/dmartin2
Project Information
Title Enhancing Irrigation Management Tools and Developing a Decision System for Managing Limited Irrigation Supplies - Enhancing The Water Optimizer
Other(s) Chris Thompson, Agricultural Economics, cthompson2@unl.edu; Paul Burgener, Panhandle Research and Extension Center, pburgener2@unl.edu; Ray Supalla, Agricultural Economics, rsupalla1@unl.edu; Gary Hergert, Panhandle Research and Extension Center, ghergert1@unl.edu 
Description

The Water Optimizer is a computer model developed in response to several years of drought across the state and to farmers facing water restrictions. The model can be used by producers to evaluate management options when water is limiting due to drought or regulations; it can also be used by water planners or policy makers who wish to estimate the farm-level economic consequences of retiring acres or regulating the water supply. Released by UNL in 2005, the model is available for all counties in Nebraska to evaluate single fields for several crop options. Irrigated crops include: corn, soybeans, sorghum, wheat, alfalfa, edible beans and sunflowers. Dryland crops include: corn, soybeans, sorghum, sunflowers, alfalfa and wheat in continuous, summer fallow and eco-fallow rotations. Producers put information into a Microsoft Excel spreadsheet, including soil type and irrigation system options. Irrigation options include center pivot or gravity irrigation systems, well or canal delivery, and systems powered by electricity, diesel or natural gas. After entering this basic information, producers enter their production costs, irrigation costs, crop prices, crop type and available water. After these parameters have been set, the program calculates what crops will be most profitable with the given costs and available water. This gives the producer a "whole farm view" in considering how to manage available water supplies.

While the Water Optimizer is useful, it is limited in that it considers economic choices and consequences one field (well) and one year at a time. Three different departments (Agronomy-Horticulture, Agricultural Economics and Biological Systems Engineering) will combine their expertise to develop information to enhance Water Optimizer by: 1) improving the tool's function for crops grown in the semiarid High Plains, including canola, camelina, chickpeas, dry beans and sunflowers; 2) expanding the tool's geographic coverage area to additional counties in Nebraska including irrigated areas in Colorado and Kansas; 3) developing the capability to evaluate risk-management alternatives on a whole-farm basis as well as field by field; and 4) developing the capability to determine the best strategies for managing multi-year water allocations. The benefits of this project will be to maintain profitability and sustain farming enterprises with a limited irrigation supply. The goal is to conduct educational programming in conjunction with the project to encourage other producers to implement practices and concepts demonstrated in this project. An additional outcome will be transferring this information to other areas of declining ground water or surface water.

The Water Optimizer tool was developed to assist in addressing water shortages created by drought and interstate water rights litigation. The current model released November 2010, supports all 93 Nebraska counties.

Project Support U.S. Department of Agriculture Risk Management Agency
Project Website http://agecon.unl.edu/wateroptimizer
Report
Current Status Underway
Topic Extension
Project's Primary Contact Information
Name Kranz, Bill
Unit Northeast Research and Extension Center
Email wkranz1@unl.edu
Phone 402-475-3857
Web Page
Project Information
Title Northeast Research and Extension Center - Haskell Agricultural Laboratory
Other(s) Charles Shapiro, Northeast Research and Extension Center, cshapiro1@unl.edu; Dave Shelton, Northeast Research and Extension Center, dshelton2@unl.edu; Sue Lackey, Conservation and Survey, slackey1@unl.edu; Terry Mader, Haskell Ag. Lab, tmader1@unl.edu 
Description

The role of the faculty and staff in this unit is to prevent or solve problems using research based information. Faculty and staff subscribe to the notion that their programs should be high quality, ecologically sound, economically viable, socially responsible and scientifically appropriate. Learning experiences can be customized to meet the needs of a wide range of business, commodity, or governmental organizations based upon the many subject matter disciplines represented. As part of the University of Nebraska, the Northeast Center faculty and staff consider themselves to be the front door to the University in northeast Nebraska. Through well targeted training backgrounds and continuous updating via the internet and other telecommunications technologies, faculty and staff have the most current information available to help their clientele.

The Haskell Ag. Lab is a University of Nebraska research farm located 1.5 miles east of the Dixon County Fairgrounds in Concord. This 320 acre farm was donated to the University of Nebraska by the C.D. Haskell family of Laurel in 1956. A number of demonstrations and projects are going on at the Haskell Ag. Lab, including a riparian buffer strip demonstration and a study to evaluate the effect of irrigation on soybean aphid population dynamics. Other studies focus on:

Subsurface Drip Irrigation: In the spring of 2007 a new subsurface drip irrigation system was installed on a 4 acre portion of the farm with sandy loam soils. The initial objective of the research is to collect field data to document crop water use rates for new corn varieties. Specifically, the work will concentrate on varieties that have different drought resistance ratings to improve the accuracy of the information provided to producers via the High Plains Regional Climate Center. In 2007, two varieties were planted and five irrigation treatments were imposed ranging from dryland to full irrigation. The data will also be used to develop improved local crop production functions for use in the Water Optimizer spreadsheet.

Hormones in Livestock Waste: This project will evaluate the fate of both naturally occurring and synthetic hormones that are associated with solid waste harvested from beef cattle feeding facilities. The research involves: 1) tracking the fate of hormonal compounds from the feedlot into surface run-off that would make its way into a liquid storage lagoon; 2) establishing stockpiled and composted sources of the solid manure removed from the feedlot; and 3) applying stockpiled and composted manure to cropland areas under different tillage systems and native grasses. Once the manure is applied the runoff potential will be evaluated using a rainfall simulator. Research will then focus on whether plants that could be a source of food for wildlife and/or domestic animals take up the hormones. (More information about this project is available; see projects listed under Dan Snow.)

Project Support Varies according to program and project - for more information see http://nerec.unl.edu/ Hormone Project funded by the U.S. Environmental Protection Agency
Project Website http://nerec.unl.edu/
Report
Current Status Continuous
Topic Extension
Project's Primary Contact Information
Name Skipton, Sharon
Unit Southeast Research and Extension Center
Email sskipton1@unl.edu
Phone 402-472-3662
Web Page http://www.southeast.unl.edu/staffdir/Skipton_Sharon
Project Information
Title Southeast Research and Extension Center
Other(s) Gary Zoubek, York County Extension, gzoubek@unl.edu 
Description Each day University of Nebraska Extension makes a difference in the lives of adults and youth. The faculty and staff in the Southeast Research and Extension Center and the 28 County Offices work to bring relevant researched based information to people in communities, towns and urban centers. Our efforts rely increasingly on partnerships with government agencies, business, industry, schools and community organizations. Working together with our partners Extension strives to strengthen the social, economic and environmental base of Nebraska's communities. Our programs must be ever-changing as Extension listens and responds to issues as they evolve. The Southeast Research and Extension District is unique because it serves both urban and rural communities Nebraska. The faculty and staff are committed to bringing the resources of the University and its research based information to the individuals and communities of Southeast Nebraska.
Project Support Varies according to program and project - for more information see http://www.southeast.unl.edu/
Project Website http://www.southeast.unl.edu/
Report
Current Status Continuous
Topic Groundwater
Project's Primary Contact Information
Name Perera-Estrada, Hugo
Unit Agronomy and Horticulture
Email hpereaestrada2@unl.edu
Phone 402-472-6085
Web Page
Project Information
Title Modeling Groundwater Nitrate Transport Beneath a Ground Water Quality Management Area in the Central Platte Region of Nebraska
Other(s) Mary E. Exner, School of Natural Resources, mspalding1@unl.edu; Roy Spalding, Agronomy and Horticulture, rspalding1@unl.edu 
Description A Ground Water Quality Management Area (GWQMA) is being evaluated to determine the effectiveness of producer practices in reducing high nitrate levels that result from excessive N-fertilizer and irrigation water applications. The assessment of nitrate movement in the primary and secondary aquifer relies on simulating groundwater flow and contaminant transport beneath the 588 km2 Phase III GWQMA. The Platte River is in hydraulic connection with the aquifer and forms the southern boundary of the model. The northern boundary parallels the northern edge of the GWQMA. Hydraulic conductivities from test hole data, irrigation well pedigree information and nitrate concentrations from 1988 to 2003 were input to a 3-D groundwater finite difference model. A Neumann or second-type boundary condition was established for the northern and southern model boundaries. Prescribed heads (Dirichlet-type boundary condition) were imposed on the upgradient and downgradient sides of the GWQMA. The thicknesses of the primary (upper) and secondary aquifers are somewhat variable in the investigated area as are hydraulic conductivities in the secondary aquifer. The groundwater model was calibrated in the steady-state mode with hydraulic head data from 1988 to 2003. The flow path and travel times within the study area result in an approximate evaluation of the susceptibility to nitrate contamination with transport. Results are described in 2-D and 3-D graphical visualizations. Hydraulic head and water quality data from adjacent monitoring wells screened in either the primary or secondary aquifers were used to quantify nitrate transport between the aquifers.
Project Support n/a
Project Website http://www.usawaterquality.org/conferences/2009/PDF/CEAP-all/Perera-Estrada09.pdf
Report
Current Status Completed
Topic Groundwater
Project's Primary Contact Information
Name Spalding, Mary Exner
Unit School of Natural Resources
Email mspalding1@unl.edu
Phone 402-472-7547
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=111
Project Information
Title Evaluation of the Effectiveness of Selected Farm Practices in Reducing Groundwater Nitrate
Other(s) Hugo Perera-Estrada, Agronomy and Horticulture, hpereaestrada2@unl.edu; Megan L. Liedte, Statistics; Roy Spalding, Agronomy and Horticulture, rspalding1@unl.edu 
Description Data from 25,961 producer reports and 1,935 irrigation wells were used to assess the effectiveness of management practices within 588 km2 of intensely irrigated corn production in the Platte River drainage in central Nebraska. The area has been regulated as a Phase III Ground Water Quality Management Area by the local Natural Resources District (NRD) for 19 years. The initial spatial analysis of the 1987 groundwater nitrate concentrations revealed an obvious concentration demarcation. Concentrations in the very contaminated northern area averaged 25.7 mg NO3-N/L while those in the southern portion averaged 9.4 mg NO3-N/L. Groundwater nitrate concentrations in the north are significantly correlated with time (r2 = 0.87) and decreased at an average annual rate of 0.24 mg NO3-N/L between 1987 and 2005. No significant concentration trend occurred in the southern area. During the 19 years the amount of N removed in grain increased at an average annual rate of 2 kg N/ha. In the north the association between the increase in N removed in grain and decrease in groundwater NO3-N concentrations is significant. The acreage converted from furrow to sprinkler irrigation increased threefold between 1988 and 2003. In the north the increase in sprinkler-irrigated acres is associated with the decrease in groundwater NO3-N concentrations. The NRD- recommended N-fertilizer rate for each corn field in the Phase III area is based upon a realistic yield goal and NRD-modified university N-fertilizer recommendation with credits for residual soil N and N available in irrigation water. From 1988 to 2003 N-fertilizer rates on 62 to 88% of the fields were within ± 56 kg N/ha (50 lb N/ha) of the NRD recommendation. The remaining fields were more likely to be fertilized at rates greater than 56 kg N/ha in excess of the recommendation than receive N at rates more than 56 kg N/ha below the NRD recommendation.
Project Support n/a
Project Website http://www.usawaterquality.org/conferences/2009/PDF/CEAP-all/Exner09.pdf
Report
Current Status Completed
Topic Hydrology
Project's Primary Contact Information
Name Chen, Xun-Hong
Unit School of Natural Resources
Email xchen2@unl.edu
Phone 402-472-0772
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=19
Project Information
Title Hydrologic Connections in the Central Platte River Basin
Other(s) Mark E. Burbach, Conservation and Survey Division, mburbach1@unl.edu; Cheng Cheng, School of Natural Resources, ccheng2@unl.edu 
Description

The hydrologic properties of channel sediments have an important role in controlling hydrologic process in streams. This study focused on the water exchange between a stream and an aquifer induced by groundwater withdrawal, with the purpose of investigating the interbedded feature of channel sediments and to evaluate its effects on the calculation of streamflow depletion. Field work was conducted at nine study sites between Kearney and Columbus during the summers of 2005 and 2006. Direct-push techniques were used to produce electrical conductivity logs and to collect sediment cores. Permeameter tests were conducted on the sediment cores. Stream-aquifer simulation models were used to evaluate streamflow depletion for various types of channel sediments.

Sediment core samples were categorized into four groups:

  • sand and gravel,
  • sand and gravel with interbedded silt and clay layers,
  • fine sand with silt or clay layers, and
  • silt and clay with some sand and gravel.

In general coarse sediments occur in the western part of the study area, and the amount of fine sand, silt and clay increases eastward along the river. However, the sediments in the top two meters are about the same for all the sites, consisting mainly of sand and gravel.

Project Support Central Platte Natural Resources District, Upper Big Blue Natural Resources District, U.S. Geological Survey (through the University of Nebraska-Lincoln Water Center), U.S. Environmental Protection Agency
Project Website
Report Chen Hydrologic Connections.pdf
Current Status Published in Journal of Hydrology 2008 352:250-266
Topic Hydrology
Project's Primary Contact Information
Name Chen, Xun-Hong
Unit School of Natural Resources
Email xchen2@unl.edu
Phone 402-472-0772
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=19
Project Information
Title Hydrologic Connections in the Big and Little Blue River Basins
Other(s) Cheng Cheng, School of Natural Resources, ccheng2@unl.edu 
Description Over extraction of groundwater near a stream can lower stream stage and induce streamflow depletion when the stream and aquifer are hydrologically connected. The Little Blue River Basin is an area of intensive groundwater development for irrigation, and the streamflow depletion in this basin was determined by an analog model (Emery, 1966). However, the post audit of the model (Alley and Emery, 1986) suggested that the decline of water-levels was overestimated and streamflow depletion was underestimated. Therefore, it is necessary to re-evaluate stream-aquifer interactions in the basin. In this study, an area is chosen for this analysis from the basin and three main streams -- the Little Blue River, Big Sandy Creek, and Spring Creek are included. Channel sediments and structures play an important role in determining stream-aquifer interactions. Firstly, field and laboratory methods including geoprobe logging and permeameter tests are utilized to investigate the channel deposits in the three main streams in the Little Blue River Basin. Results show that channels have low hydraulic-permeable layers which reduce their hydraulic connections to the adjacent aquifers. Secondly, a groundwater flow model is constructed to identify the hydraulic properties of the aquifer and evaluate streamflow depletion under groundwater withdrawals in the study area. Modeling results indicate that streamflow depletion is very low and aquifer storage loss is the main source of groundwater pumpage.
Project Support Upper Big Blue Natural Resources Distrect, Lower Big Blue Natural Resources District, Little Blue Natural Resources District
Project Website
Report
Current Status Completed
Topic Hydrology
Project's Primary Contact Information
Name Chen, Xun-Hong
Unit School of Natural Resources
Email xchen2@unl.edu
Phone 402-472-0772
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=19
Project Information
Title Investigation of Stream-Aquifer Hydrologic Relationship for Clear Creek in Polk and Butler Counties
Other(s) Weihong Dong, Jilin University; Zhaowei Wang, School of Natural Resources; Gengxin Ou, School of Natural Resources; Can Liu, School of Natural Resources, can.liu1989@huskers.unl.edu 
Description

Vertical hydraulic conductivities (Kv) of both streambed and point bars can influence water and solute exchange between streams and surrounding groundwater systems. The sediments in point bars are relatively young compared to the older sediments in the adjacent aquifers but slightly older compared to submerged streambeds. Thus, the permeability in point bar sediments can be different not only from regional aquifer but also from modern streambed. However, there is a lack of detailed studies that document spatial variability of vertical hydraulic conductivity in point bars of meandering streams. In this study, the authors proposed an in situ permeameter test method to measure vertical hydraulic conductivity of the two point bars in Clear Creek, Nebraska, USA. We compared the Kv values in streambed and adjacent point bars through 45 test locations in the two point bars and 51 test locations in the streambed.

The Kv values in the point bars were lower than those in the streambed. Kruskal–Wallis test confirmed that the Kv values from the point bars and from the channel came from two statistically different populations. Within a point bar, the Kv values were higher along the point bar edges than those from inner point bars. Grain size analysis indicated that slightly more silt and clay particles existed in sediments from inner point bars, compared to that from streambed and from locations near the point bar edges. While point bars are the deposits of the adjacent channel, the comparison of two groups of Kv values suggests that post-depositional processes had an effect on the evolution of Kv from channel to point bars in fluvial deposits.

We believed that the transport of fine particles and the gas ebullition in this gaining stream had significant effects on the distribution of Kv values in a streambed-point bar system. With the ageing of deposition in a floodplain, the permeability of point bar sediments can likely decrease due to reduced effects of the upward flow and gas ebullition.

Project Support Upper Big Blue Natural Resources District, Chinese Ministry of Education, National Natural Science Foundation of China
Project Website
Report Chen_Hydraulic_Conductivity.pdf
Current Status Completed
Pic 1 Project Image
Pic Caption 1 Map showing the study site in Clear Creek, Nebraska 
Pic 2 Project Image 2
Pic Caption 2 Schematic for the in situ permeameter test in the point bars 
Topic Hydrology
Project's Primary Contact Information
Name Cheng, Cheng
Unit School of Natural Resources
Email ccheng2@unl.edu
Phone 402-472 0772
Web Page http://snr.unl.edu/aboutus/who/people/graduatestudent-member.asp?pid=798
Project Information
Title Statistical Distribution of Streambed Vertical Hydraulic Conductivity along the Platte River, Nebraska
Other(s) Xun-Hong Chen, School of Natural Resources, xchen2@unl.edu, Jinxi Song, Deming Wang 
Description Streambed vertical hydraulic conductivity (Kv) plays an important role in understanding and quantifying the stream-aquifer interactions. While several researchers have discussed the spatial variability of streambed horizontal hydraulic conductivity or Kv at one or several close-located sites in a river, they did not develop any statistical distribution analysis of streambed Kv at distant sites along a large river. In this paper, the statistical distribution and spatial variation of streambed Kv at 18 test sites in a 300-km reach of the Platte River in Nebraska are presented. Insitu permeameter tests using the falling-head method were carried out to calculate the streambed Kv values. Fine-grained sediments transported by two tributaries, the Loup River and the Elkhorn River, to the Platte River appear to result in lower streambed Kv values downstream of the confluences between the Platte River and the tributaries. The streambed Kv values were found to be normally distributed at nearly each test site. When the correlated Kv values were eliminated from the grid sampling plots, the remaining independent sub-datasets of streambed Kv values were still in normal distribution at each test site. Furthermore, the combined streambed Kv values upstream of the first confluence between the Platte River and the Loup River was normally distributed, which may be due to the lack of tributaries in-between and thus streambed sediments were well distributed in this reach and belonged to a single population of hydraulic conductivity values. In contrast, the combined dataset of all measurements conducted downstream of this confluence was no longer in normal distribution, presumably as a result of the mixing of different sediment sources.
Project Support Lower Platte North Natural Resources District, Program for Changjiang Scholars and Innovative Research Team in University of Ministry of Education of China
Project Website
Report Cheng_Distribution.pdf
Current Status Published in Water Resources Management DOI 10.1007/s11269-010-9698-5
Topic Hydrology
Project's Primary Contact Information
Name Harvey, F. Edwin
Unit School of Natural Resources
Email feharvey1@unl.edu
Phone 402-472-8237
Web Page http://eas.unl.edu/people/faculty_page.php?lastname=Harvey&firstname=Ed&type=ADJ
Project Information
Title Hydrologic Research in the Rainwater Basin Wetlands of South-Central Nebraska
Description

As part of this project, Harvey and his students are conducting research to unravel the hydrology of central Nebraska's Rainwater Basin wetlands. These wetlands are of international importance as habitat for millions of migratory water birds. In addition, these playa wetlands may contribute to groundwater recharge and water quality improvement. However, many of the wetlands have been drained, and those remaining suffer functional impairment due to sedimentation and pesticide and fertilizer runoff.

Most of the remaining Rainwater Basin wetlands are geographically isolated. Currently research is underway to investigate the role of these wetlands in providing groundwater recharge and water quality improvement. This is a significant environmental issue of concern because groundwater in this region is of vital importance, providing drinking and irrigation water. Moreover, groundwater levels are declining throughout much of the region. Levels of nitrate and atrazine exceed drinking water standards in some parts of the basin. Most of the remaining playa wetlands are impaired by sediment and there is an active program to restore the wetlands by removing this sediment. Study sites are located in Phelps, Kearney, Clay, Fillmore, and York counties (see map below).

Three components need to be measured when establishing a hydrologic budget for these closed basin wetlands which are surface storage, evapotranspiration (ET), and groundwater recharge. ET is calculated by the Bowen-Ratio Energy Budget (BREB) Method with the aid of a Bower Tower. Surface storage and recharge data will be aided by stilling wells and drive-point wells, respectively. Hydroperiods and plant community diversity are being determined before and after sediment removal to evaluate the impact of in-washed sediments on recharge and underlying groundwater quality. Chloride concentrations obtained from upland runoff collectors will be incorporated into the Chloride Mass-Balance Method along with precipitation and sediment chloride concentrations to obtain recharge fluxes for a wetland site.

Two Master's theses and one Bachelor's thesis have been completed as part of this project:

  • Wilson, Richard D. (2010), Evaluating Hydroperiod Response in the Rainwater Basin Wetlands of South-Central Nebraska, MS Thesis, UNL School of Natural Resources, 163 p.
  • Foster, Sarah E., (2010), Temporal and Spatial Variations of Ions, Isotopes and Agricultural Contaminants in Surface Waters and Groundwater of Nebraska’s Rainwater Basin Wetland Region, MS Thesis, UNL Department of Earth and Atmospheric Sciences, 185 p.
Project Support U.S. Environmental Protection Agency
Project Website http://snr.unl.edu/harvey/projectrainwater.htm
Report
Current Status Continuing
Pic 1 Project Image
Pic Caption 1 The Rainwater Basin area of Nebraska. 
Topic Hydrology
Project's Primary Contact Information
Name Lenters, John
Unit School of Natural Resources
Email jlenters2@unl.edu
Phone 402-472-9044
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=743
Project Information
Title On Basin Residence Time and Annual Hydrology: Development of Annual Hydrology Model of the Sandhills Rivers
Other(s) Erkan Istanbulluoglu, University of Washington, erkani@u.washington.edu; Durelle Scott, Virginia Tech, dscott@vt.edu; Tiejun Wang, University of Washington-Seattle, tjwang@u.washington.edu 
Description

Simple models of annual and mean annual basin runoff and evapotranspration, such as the one proposed by Budyko, are useful for investigating the relationship between river flow and climate, and planning water storage structures in basins where long term streamflow measurements are not available. Such models are often based on the assumption that annual precipitation is in balance with annual runoff and evapotranspiration, and change in water storage of the basin is negligible. In basins where groundwater is the dominant source of streamflow this assumption hardly holds.

In this study first we develop a technique to investigate groundwater residence time to identify time scales over which a simple model of mean annual runoff can be meaningfully used. The model is applied in the Niobrara and Loup Rivers. Second we develop an annual hydrology model by solving the rate of change in basin storage. The runoff component of the model is based on the well-known linear reservoir model and a parameterization to characterize runoff on saturated areas. River water storages and streamflow diverted for irrigation are included as inputs in the model. The model explained as high as 80% of the annual variability of runoff in the Niobrara River at the Sparks gage. The model underscores the importance of saturation overland flow in the basin. Finally we used the model to investigate climate change scenarios, including extreme dry and wet conditions, as well as scenarios for the Medieval Warm Period during which Sandhills were destabilized as suggested by geological evidence.

Project presentation at the 2008 Water Colloquium

Project Support National Science Foundation
Project Website
Report Lenters_Groundwater.pdf
Current Status Published "On the role of groundwater and soil texture in the regional water balance: An investigation of the Nebraska Sand Hills", USA, Water Resour. Res., 45, W10413, doi:10.1029/2009WR007733.
Topic Invasive Species
Project's Primary Contact Information
Name Allen, Craig
Unit Nebraska Cooperative Fish and Wildlife Research Unit
Email callen3@unl.edu
Phone 402-472-0229
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=647
Project Information
Title Monitoring, Mapping and Risk Assessment for Non-Indigenous Invasive Species in Nebraska
Other(s) Karie Decker, Nebraska Invasive Species Project Coordinator, invasives@unl.edu 
Description

Biological invasions are a growing threat to both human enterprise and ecological systems. This project provides resources to the public and private sector on: 1) the potential spread and impact of non-indigenous species in Nebraska; 2) actual and potential maps of non-indigenous species range (habitat specific maps at high resolution); 3) information regarding identification and management of potential invaders; 4) centralized information on management and impacts and potential spread of currently established non-indigenous species (a web portal); and 5) outreach within Nebraska to county-level governments and individual stakeholders regarding the management, surveillance and control of non-indigenous species. On February 7-8, 2008 a conference on non-indigenous species impacts, spread and management was held, focusing on state-of-our-knowledge and coordination of disparate management and information-provisioning efforts with a goal towards unification of disparate efforts.

This project is meant to build momentum towards a cohesive non-indigenous species biosecurity and management system in Nebraska that is integrated and relatively seamless across institutional boundaries. Spatially - based risk assessments that focus on non-indigenous invasive species impacts on at - risk native species and communities in Nebraska have been initiated with funding from the U.S. Geological Survey and the Nebraska Game and Parks Commission. The results and predictive models generated by this project will be delivered and made widely available to policy makers, management practitioners and landowners in Nebraska. Additional general information about potential invasive species and their impacts will be made easily accessible. Most of the goals listed above will produce and disseminate products that are dynamic, with interactive elements for the public and managers, including mapping of habitat-specific current and potential distributions of invasive species as well as a portal through which the public can inform the entities responsible for management of invasive species occurrence and spread - and vice versa.

Project Support U.S. Geological Survey, Nebraska Game and Parks Commission, Nebraska Environmental Trust
Project Website http://snr.unl.edu/invasives
Report
Current Status Continuing
Topic Invasive Species
Project's Primary Contact Information
Name Allen, Craig (advisor)
Unit Nebraska Cooperative Fish and Wildlife Research Unit
Email callen3@unl.edu
Phone 402-472-0229
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=647
Project Information
Title The Effect of Common Reed (Phragmites australis) on River Otter (Lontra canadensis) Habitat Use
Other(s) Amy Williams, amy_ruth18@hotmail.com; Sam Wilson, Nebraska Game and Parks Commission, sam.wilson@nebraska.gov 
Description The river otter (Lontra canadensis) is a threatened species in Nebraska and little is known about its local ecology. The recent invasion of the Platte River by the common reed (Phragmites australis) has altered the riverscape and could have negative effects on otters. Since the reintroduction of river otters to several of Nebraska's river basins beginning in the late 1980's, there have been no quantitative studies examining the status of the population or habitat use of river otters in the state. The recent invasion of P. australis in the Big Bend region of the Platte River has made the need to fill this knowledge gap more critical. We are examining the effects of P. australis on river otters by determining if otters use river ways dominated by P.australis or den in areas of P. australis more or less than expected relative to availability. Sixteen otters were trapped, radio tagged, and tracked between 2006 and 2009. 517 den/resting locations were identified, 127 of which were unique locations. Den/resting site habitat use was compared to availability to determine if otters were using P. australis in proportion to availability. Females use unique sites in P. australis more than expected but males do not. When all locations were analyzed, both males and female used P. australis in proportion to availability. P. australis provides cover for females and is likely used for resting locations when traveling with pups. Information on otter abundance and habitat use from this study will support the creation and implementation of a state river otter management plan and ensure the persistence of a viable otter population in Nebraska.

Project Support

Nebraska Cooperative Fish and Wildlife Research Unit, Nebraska Game and Parks Commission
Project Website http://snr.unl.edu/necoopunit/research.main.html#river_otters
Report
Current Status Completed
Topic Production Agriculture
Project's Primary Contact Information
Name Ferguson, Richard
Unit Agronomy and Horticulture
Email rferguson1@unl.edu
Phone 402-472-1144
Web Page http://agronomy.unl.edu/ferguson
Project Information
Title Interactions of Water and Nitrogen Supply for Irrigated Corn across Field Landscapes
Other(s) Tim Shaver, West Central Research & Extension Center, tim.shaver@unl.edu; Nicholas Ward, Agronomy & Horticulture, ward.nick.c@gmail.com; Suat Irmak, Biological Systems Engineering, sirmak2@unl.edu; Simon van Donk, West Central Research & Extension Center, simon.vandonk@unl.edu; Daran Rudnick, Agronomy & Horticulture, daran.rudnick@huskers.unl.edu; Brian Wienhold, Agronomy & Horticulture, bwienhold1@unl.edu 
Description

Water and nitrogen (N) supply to a crop can interact throughout the growing season to influence yield potential. The increasing availability of variable rate irrigation systems to growers in irrigated regions, along with existing capacity for variable rate fertilization, provides the opportunity for temporal and spatial management of inputs of water and nitrogen. This study was initiated in 2011 to explore interactions of landscape and soil features with water and N inputs on grain yield and water and N use efficiency. Five field locations were used across Nebraska to evaluate the effects of landscape variation, climate, and capacity for temporal and spatial management of water and N. Preliminary results in 2011 showed that at sites with significant topographic variation these features influenced grain yield as much as the rate of irrigation water or nitrogen fertilizer, indicating the importance of considering spatial variation in landscape features when optimizing rates and timing of water and nitrogen.

Five field locations were used for the study in 2011. Two sites were at University of Nebraska-Lincoln (UNL) research laboratories the South Central Agricultural Laboratory (SCAL) and the Brule Water Resources Laboratory (BWL). Three sites were located on cooperating producer’s fields one in Morrill County, and two in Hamilton County. The UNL research sites included more detailed measurements, and inclusion of treatments that were more yield-limiting than those on producer fields. Locations were situated across a rainfall and soils gradient in Nebraska, allowing evaluation of site-specific water/N management interactions over a range of annual rainfall and soil types. Three of the sites included the use of variable rate irrigation systems and two of the sites implemented canopy sensor-based in-season N treatments.

Project Support John Deere
Project Website
Report Ferguson_Landscape.pdf
Current Status Completed
Pic 1 Project Image
Pic Caption 1 Study locations in 2011, with precipitation gradient across Nebraska 
Topic Production Agriculture
Project's Primary Contact Information
Name Supalla, Raymond
Unit Agricultural Economics
Email rsupalla1@unl.edu
Phone 402-472-1792
Web Page http://agecon.unl.edu/supalla
Project Information
Title Economic and State Budget Cost of Reducing the Consumptive Use of Irrigation Water in the Platte and the Republican Basins
Other(s) Brian McMullen, Agricultural Economics, bmcmullen2@unl.edu 
Description

The terms of the Cooperative Agreement for the Platte Basin and the Supreme Court settlement decision for the Republican Basin both require that Nebraska reduce its consumptive use of irrigation water. This analysis evaluated the economic and the budgetary costs of meeting these requirements. Both the on-farm and off-farm costs were evaluated for both land retirement and water allocation programs, implemented in several different ways, over three alternative time periods, 10, 25 and 50 years.

The on-farm economic costs were defined as the change in net farm income associated with less irrigation. Off-farm economic costs were defined as the statewide change in household income resulting from changes in irrigation, as the effects ripple through the Nebraska economy. Budgetary costs were defined as the cost to the state budget (taxpayers) of policies which compensate irrigators for reducing consumptive use are implemented. Statewide economic costs were found to be lower for land retirement than for allocation programs, assuming the same total change in consumptive use. Total budgetary costs depended primarily on: where the irrigation reductions occurred (proximity to river); on how long the program was continued (number of years), and on whether irrigation was reduced voluntarily with incentives, or by regulation, or by some combination of regulation and incentives. It was found that policy makers could minimize the cost of reducing consumptive use from irrigation and augmenting stream flow by purchasing rather than leasing irrigation rights, by using a regulatory rather than a willing seller incentive approach, and by reducing irrigation at locations close to the river.

More on this research in a UNL Agricultural Economics working paper

Project Support n/a
Project Website
Report
Current Status Completed
Topic Property Values
Project's Primary Contact Information
Name Shultz, Steve
Unit UNO Real Estate Research Center
Email sshultz@mail.unomaha.edu
Phone 402-554-2810
Web Page http://cba.unomaha.edu/dir/HomePageBio.cfm?id=347
Project Information
Title Ongoing UNO/UNL Research on the Determinants of Agricultural Land Values: How Irrigation Contributes to Land Values in Western and Central Nebraska
Other(s) Nick Schmitz, UNO Real Estate Research Center 
Description

Hedonic (mass appraisal) land valuation models were estimated in the Republican and Platte watersheds of Central and Western Nebraska. These models are based on assumption that the buyers and sellers of agricultural land are able to accurately assess the value of irrigation when negotiating sale contract prices, and that irrigation equipment can be distinguished from land and irrigation values. Alternative models were estimated using various combinations of explanatory variables (all measured at the parcel level of analysis). These include: soil productivity measures, topography precipitation, parcel size, cropping patterns, topography, aquifer thickness, well pumping capacity, distances to elevators and towns, and irrigation systems.

The location of all agricultural land sales statewide (2000-2007) and estimated irrigation values in the Platte and Republican Watersheds were identified. Preliminary mass appraisal model results were summarized in tables and the locations of retired irrigation parcels in the Republican Watershed (as part of a 2006 NE DNR and USDA Pilot Program) were identified. The value of irrigated cropland is on average $615/acre (this is the value of irrigated cropland only and does not include the value dryland corners within pivot systems). As well, there are numerous areas and site-specific parcels within the watershed with both lower and higher irrigation values. In fact, we have calculated irrigation values for all of the natural resource districts in the Republican watershed: they range from $488/acre to $948/acre. These estimates are still considered 'preliminary' and may be subject to revision. These irrigation values also do not account for premiums above and beyond marginal market values that farmers and landowners will likely require to willingly participate in future irrigation retirement programs.

More on this research in a journal of the Western Agricultural Economics Association

Project Support U.S. Department of Agriculture Water and Watershed Program
Project Website
Report
Current Status Complete (up to 2007)
Topic Riparian Vegetation Water Use
Project's Primary Contact Information
Name Irmak, Suat
Unit Biological Systems Engineering
Email sirmak2@unl.edu
Phone 402-472-4865
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=47
Project Information
Title Evapotranspiration crop coefficients for mixed riparian plant community and transpiration crop coefficients for Common reed, Cottonwood and Peach-leaf willow in the Platte River Basin, Nebraska-USA
Other(s) Isa Kabenge, Biological Systems Engineering, ikabenge2@unlnotes.unl.edu; Daran Rudnick, Biological Systems Engineering; Stevan Knezevic, Northeast Research and Extension Center, sknezevic2@unl.edu; Duane Woodward, Central Platte Natural Resource District, woodward@cpnrd.org; Milt Moravek, Central Platte Natural Resource District 
Description

Application of two-step approach of evapotranspiration (ET) crop coefficients (Kc) to approximate a very complex process of actual evapotranspiration (ETa) for field crops has been practiced by water management community. However, the use of Kc, and in particular the concept of growing degree days (GDD) to estimate Kc, have not been sufficiently studied for estimation of evaporative losses from riparian vegetation. Our study is one of the first to develop evapotranspiration crop coefficient (KcET) curves for mixed riparian vegetation and transpiration (TRP) crop coefficients (KcTRP) for individual riparian species as a function GDD through extensive field campaigns conducted in 2009 and 2010 in the Platte River Basin in central Nebraska, USA.

Project Support
Project Website
Report Irmak_Platte_River_ET.pdf
Current Status Completed
Pic 1 Project Image
Pic Caption 1 Location of the Bowen ratio energy balance system (BREBS) at the Common reed-dominated Cottonwood and Peach-leaf willow riparian plant community in the Platte River Basin in central Nebraska, USA. 
Topic Survey
Project's Primary Contact Information
Name Joseph Hamm
Unit jhamm2@nebraska.edu
Phone 402-472-5678
Web Page http://ppc.unl.edu/
Project Information
Title Platte River Habitat Partnership Survey
Other(s) Lisa Pytlik Zillig, Public Policy Center, lpytlikz@nebraska.edu, Alan Tomking, Public Policy Center, atomkins@nebraska.edu 
Description

Nebraska’s native prairies are a valued resource and under constant anthropogenic demand and degradation. By engaging land owners in voluntary programs, the Platte River Habitat Partnership aims to restore and enhance this important natural resource. In this project, the Public Policy Center conducted a survey to assess land owners’ perceptions of the Platte River Habitat Partnership to help direct the Partnership’s second phase. Specifically, land owners who live in the region covered by the Partnership but did not participate, and those that did participate in the Partnership were surveyed in order to answer four key questions: 1. How knowledgeable are these land owners about the Partnership? 2. What is the nature of these land owners’ interactions with the Partnership? 3. How is the Partnership itself generally perceived by these land owners? 4. What would encourage land owners who had not participated in the Partnership to participate?

Project Support The Nature Conservancy
Project Website http://ppc.unl.edu/project/PlatteRiverHabitatPartnershipSurvey
Report PRHP_Report.pdf
Current Status Completed
Topic Wastewater
Project's Primary Contact Information
Name Bartelt-Hunt, Shannon
Unit Civil Engineering
Email sbartelt2@unl.edu
Phone 402-554-3868
Web Page http://www.engineering.unl.edu/civil/faculty/ShannonBartelt-Hunt.shtml
Project Information
Title The occurrence of illicit and therapeutic pharmaceuticals in wastewater effluent and surface waters in Nebraska
Other(s) Daniel D. Snow, School of Natural Resources, dsnow1@unl.edu; Teyona Damon; Johnette Shockley; Kyle Hoagland, School of Natural Resources, khoagland1@unl.edu 
Description The occurrence and estimated concentration of twenty illicit and therapeutic pharmaceuticals and metabolites in surface waters influenced by wastewater treatment plant (WWTP) discharge and in wastewater effluents in Nebraska were determined using Polar Organic Chemical Integrative Samplers (POCIS). Samplers were installed in rivers upstream and downstream of treated WWTP discharge at Lincoln, Grand Island, and Columbus, downstream of Hastings' WWTP discharge, and from Omaha's effluent channel just prior to it being discharged into the Missouri River. Based on differences in estimated concentrations determined from pharmaceuticals recovered from POCIS, WWTP effluent was found to be a significant source of pharmaceutical loading to the receiving waters. Effluents from WWTPs with trickling filters or trickling filters in parallel with activated sludge resulted in the highest observed in-stream pharmaceutical concentrations. Azithromycin, caffeine, 1,7 - dimethylzanthine, carbamazepine, cotinine, DEET, diphenhydramine, and sulfamethazine were detected at all locations. Methamphetamine, an illicit pharmaceutical, was detected at all but one of the sampling locations, representing only the second report of methamphetamine detected in WWTP effluent and in streams impacted by WWTP effluent.
Project Support n/a
Project Website
Report Bartelt-Hunt_Wastewater.pdf
Current Status Published in Environmental Pollution 2009 157:786-791
Topic Wastewater
Project's Primary Contact Information
Name Woldt, Wayne
Unit Southeast Research and Extension Center
Email wwoldt1@unl.edu
Phone 402-472-8656
Web Page http://bse.unl.edu/wwoldt1
Project Information
Title Onsite Wastewater Treatment System Certification Training and Education Project
Other(s) Jan Hyngstrom, Biological Systems Engineering, jhygnstrom1@unl.edu; Sharon Skipton, Southeast Research and Extension Center, sskipton1@unl.edu 
Description

The goal of this project is to enable onsite wastewater treatment system professionals to apply science-based onsite wastewater design, installation, and maintenance practices and thereby protect water resources and human health. As of December 31, 2005, onsite professionals must pass exams to be certified pumpers, installers, and/or inspectors in the state of Nebraska. In-depth curriculum for Nebraska onsite wastewater system installers, inspectors and pumpers was developed to address this issue. The curriculum helps individuals prepare for exams, as well as help professionals apply science-based practices to protect water resources.

During 2005 and 2006, UNL Extension had 733 educational training contacts. Knowledge and competency was demonstrated by 86 percent passing their exam(s). Results from a follow-up survey of 460 of those who had attended training indicated pumpers (90%), installers (99%) and inspectors (100%) increased knowledge. Pumpers (76%), installers (71%), and inspectors (90%) reported they had made practices changes which would result in water quality and human health being better protected.

Certification training continues on an annual basis and new curriculum is being developed for advanced alternative treatment systems. These systems can achieve greater water quality protection in vulnerable areas including those with high groundwater levels and/or sandy soils. Merrick, Hall, and Hamilton Counties have geographic areas of high risk from traditional onsite wastewater treatment systems due to these factors. Alternative systems could greatly reduce the risk of water quality degradation from nitrate and other contaminants in these areas.

Educational materials have also been developed and delivered for homeowners with onsite systems. The goal is to empower rural homeowners to protect water resources and human health through application of science-based onsite system maintenance and operation practices. Training was delivered in Grand Island and to 50 residents with onsite systems at Turtle Beach near Central City.

Project Support Nebraska Department of Environmental Quality, Nebraska Onsite Waste Water Association
Project Website http://water.unl.edu/web/sewage/home
Report
Current Status Continuous
Topic Water Quality
Project's Primary Contact Information
Name Dvorak, Bruce
Unit Civil Engineering
Email bdvorak1@unl.edu
Phone 402-472-3431
Web Page http://www.engineering.unl.edu/civil/faculty/BruceDvorak.shtml
Project Information
Title Arsenic and Uranium in Drinking Water Training and Education Project
Other(s) Wayne Woldt, Biological Systems Engineering, wwoldt1@unl.edu; Sharon Skipton, Southeast Research and Extension Center, sskipton1@unl.edu; Gina Rust 
Description

When new Environmental Protection Agency Safe Drinking Water Act standards for arsenic and uranium were enacted, 82 Nebraska public water supplies had arsenic concentrations above the maximum level allowed and 20 had uranium above the standard, including public water supplies in Hamilton, Hall, and Merrick counties. Since arsenic and uranium are naturally occurring in rocks and soil, private water supplies in these geographic areas could also be at risk of having elevated concentrations, possibly putting families at risk from chronic exposure.

A UNL Extension team with a drinking water focus developed and delivered training to UNL Extension faculty/staff in targeted areas at high risk for naturally occurring arsenic and/or uranium. Twelve training sessions were delivered in 2005 including training in Merrick and Hall Counties. Thirty-nine extension personnel with a focus or job description other than drinking water were trained, including 3 in Hall County and 3 in Merrick County. Participants increased their knowledge of the topic in order to work better with owners of private drinking-water wells in the high risk areas. Of those returning an evaluation, 92% strongly agreed or agreed their knowledge increased in regard to arsenic and uranium occurrence, risk, testing, and treatment. These faculty and staff have gone on to provide information and education at the local level to private well owners.

Training on arsenic and uranium in drinking water was delivered at the Nebraska Well Drillers Winter Short Course in 2006 and information on arsenic in drinking water was presented in 2007. Nearly 300 water well professionals attended in 2006 and approximately 250 attended in 2007. Seven percent of 2006 participants evaluating the program indicated the arsenic and uranium program was the best topic during the event, and 19% indicated they were interested in learning more about the topic. Participants indicated they would use the information gained to "spread knowledge on arsenic and uranium to pivot system owners," "educate/inform constituents, customers," "expand markets in arsenic and uranium testing," or "provide safer water."

UNL Extension also delivered training on arsenic and uranium in drinking water at a Professionals Seminar in 2006. Thirty-eight professionals attended. Several professionals involved stated that the focused three-hour presentation gave them an excellent overview of the pertinent design issues which communities and engineers should consider when selecting a method of dealing with high arsenic and uranium levels. They especially appreciated the mix of technical presentations with a panel discussion by community members, regulators, and local engineers.

Project Support Well Driller Training - Nebraska Well Drillers Association Professional Seminar - Nebraska Section of the American Water Works Association, Nebraska Health and Human Services System
Project Website
Report
Current Status Completed
Topic Water Quality
Project's Primary Contact Information
Name Gosselin, Dave
Unit School of Natural Resources
Email dgosselin2@unl.edu
Phone 402-472-8919
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=42
Project Information
Title Geologic Rehabilitation of Public Water Supply Wells Having High Uranium
Description

The water delivered by Clarks' public water supply wells exceeded the 30 ppb maximum contaminant level (MCL) for uranium. This project tested whether well rehabilitation, hydrogeologic avoidance and well management could be used to reduce the concentration of uranium. Interval sampling (i.e., collecting water quality samples at different depths) indicated uranium concentrations were at or below the uranium MCL at two of three different depths. Based on this data and in consultation with Nebraska Health and Human Services personnel, it was decided that a variable frequency drive pump would be installed. The installation of this pump allows operators to vary the pumping rate, thereby, reducing stress on the aquifer. Because of the distinctly lower uranium concentrations near the bottom of the well, a packer system was installed to isolate the lower 2/3 of the well screen. This project concluded that uranium concentrations decreased with depth and uranium concentrations were influenced by the introduction of oxygen into the subsurface. Further study and potential experimentation with uranium concentrations and aeration in the test well and production well is suggested.

Recently, researchers have been examining the potential for microbial communities to affect the behavior of dissolved uranium at Clarks. The metabolism of these communities may facilitate the sorption and immobilization of dissolved uranium to available metals, such as iron or sulfide. Genomic analyses of water and biofilm samples taken in April 2007 from the Clarks public water supply well and monitoring well displayed presence of metal reducing and other unknown bacteria. Further genomic analyses will provide a more specific map of the diversity of these microbes in both Clarks wells, and should improve our understanding of how the presence of these communities affects the geochemistry observed in these wells.

Project Support Nebraska Department of Health and Human Services
Project Website http://snr.unl.edu/nebraskawaterquality/
Report
Current Status Completed
Topic Water Quality
Project's Primary Contact Information
Name Riens, John
Unit Wisconsin Ecological Services Field Office, U.S. Fish & Wildlife Service
Email John_Riens@fws.gov
Phone 541-885-2503
Web Page http://www.fws.gov/
Project Information
Title Macroinvertebrate Response to Buffer Zone Quality in the Rainwater Basin Wetlands of Nebraska
Other(s) W. Wyatt Hoback, Biology UNK, hobackww@unk.edu; Matt Schwarz, U.S. Fish & Wildlife Service 
Description

The Rainwater Basin is one of the most endangered wetland ecosystems in North America. This ecosystem is critical to many species including migratory waterfowl. Land use and runnoff from agriculture and cattle confinement operations are likely to be reducing the basin's health and diversity, however little information exists concerning macroinvertebrates. Twenty-two locations were assessed for water quality parameters, vegetation composition, and macroinvertebrates identified to genus. Samples were collected biweekly starting in April through July for three years. Macroinvertebrate diversity was impacted in areas with little buffer although the effects were not pronounced. Institution of a more effective vegetative buffers strip may reverse this trend to improve ecosystem quality and provide for invertebrate resources for migratory birds.

Click here to see a poster about this research

Project Support n/a
Project Website
Report
Current Status Completed
Topic Water Quality
Project's Primary Contact Information
Name Tang, Zhenghong
Unit Architecture
Email ztang2@unl.edu
Phone 402-472-9281
Web Page http://architecture.unl.edu/people/bios/tang_zhenghong.shtml
Project Information
Title Assessment of Sedimentation and Water Quality Conditions in the Rainwater Basin's Playa Wetlands
Other(s) Mark Kuzila, School of Natural Resources, mkuzila1@unl.edu; Xu Li, Department of Civil Engineering, xuli@unl.edu; Amy Burgin, School of Natural Resources, aburgin2@unl.edu 
Description

The overall goal of this project is to prioritize watershed restoration/acquisition programs in the Rainwater Basin (RWB) by examining playa wetlands’ sedimentation and water quality conditions using the Revised Universal Soil Loss Equation 2 (RUSLE2) and the fly ash technology.

Three specific tasks are included in this project:

  1. Calculate and map the sedimentation rates and the age of deposition for all playa wetlands in RWB
  2. Consolidate existing water quality data of the RWB playa wetlands and evaluate the key factors influencing playa wetland water quality
  3. Assess the effects of sedimentation control practices and prioritize future watershed restoration/acquisition programs

The final products of this project include:

  1. An atlas of wetland sedimentation maps and a risk report highlighting the areas in watersheds with the highest sedimentation rates
  2. A geodatabase and an evaluation report on the water quality conditions of the playa wetlands in the RWB
  3. A written assessment report for sedimentation control practices and a watershed index to prioritize future conservation/acquisition programs
Project Support U.S. Environmental Protection Agency
Project Website http://www.unl.edu/playawetlands/
Report
Current Status Underway
Topic Watershed Management
Project's Primary Contact Information
Name Allen, John C.
Unit Agricultural Economics
Email jallen1@unl.edu
Phone 435-797-9732
Web Page
Project Information
Title Socio-Cultural Study of the Middle Platte River Region of Nebraska: Building Capacity for Community-Based Conservation
Description Telephone surveys, focus group interviews, and in-depth interviews were conducted in 1997 and community profiles developed in 1998 to provide an integrated picture of the social and cultural factors that influence how Middle Platte River residents and communities perceive the river; where their futures fit with the perceived best case scenarios; and the future they see for themselves, their family, and their community.
Project Support U.S. Environmental Protection Agency
Project Website http://watercenter.unl.edu/PRS/PlatteRiverReports/Socio-Cultural%20Study%20of%20the%20Middle%20Platte%20River.pdf
Report
Current Status Completed
Topic Watershed Management
Project's Primary Contact Information
Name Jenkins, Allan
Unit Economics
Email
Phone
Web Page
Project Information
Title Middle Platte Socioeconomic Overview
Description This report was published in February 1999 and designed to provide a common body of knowledge to all groups engaged in decisions regarding the Platte River. Recognizing that different decision-makers have different levels of prior knowledge concerning the Platte River, the author attempted to create a document suitable for a range of audiences that also facilitated discussion.
Project Support U.S. Environmental Protection Agency
Project Website http://watercenter.unl.edu/PRS/PlatteRiverReports/The%20Platte%20Watershed%20Program.pdf
Report
Current Status Completed
Topic Wetlands
Project's Primary Contact Information
Name Tang, Zhenghong
Unit Architecture
Email ztang2@unl.edu
Phone 402-472-9281
Web Page http://architecture.unl.edu/people/bios/tang_zhenghong.shtml
Project Information
Title Developing LiDAR-Derived Wetland Maps To Assess Conservation Design Practices For Playa Wetlands In Rainwater Basin
Other(s) Ed Harvey, School of Natural Resources, feharvey1@unl.edu; Xu Li, Department of Civil Engineering 
Description The overall goal of this project is to provide wetland managers with topographically-correct 3-D wetland maps to prioritize wetland conservation efforts and assess wetland conservation design practices. This project addresses three specific tasks for the playa wetlands: 1) Establish accurate, topographically-correct, 3-D wetland maps to relate weather conditions and wetland functions; 2) Develop a measurable Restorable Wetland Index to prioritize playa wetland and drainages conservation; 3) Assess wetland conservation design practices for watershed-based wetland conservation. This research will use high-resolution Light Detections And Ranging (LiDAR) data to create next-generation wetland maps for playa wetlands. The research provides the missing link in conservation design as these data will provide accurate elevation measures to delineate watershed extent and determine the impact of individual hydrologic modifications. This project will be one of the first to integrate LiDAR data and a hydrologic modifications datasets to find the relations of current weather conditions and wetland functions. This project provides reliable, accurate wetland spatial parameters to prioritize playa wetland conservation and assess the effectiveness of existing wetland conservation design practices. The wetland conservation design tools and protocols will be examined in two pilot counties in Nebraska. The intellectual merit of the research is based on advancing knowledge linkage of wetland mapping technologies and wetland function modifications, and showing how to adapt wetland conservation designs. The outputs from this project provide practical protocols for state/regional/local wetland managers and thus ensure "no net loss" in quality and quantity of wetlands.
Project Support US EPA
Project Website
Report
Current Status Completed
Topic Wildlife
Project's Primary Contact Information
Name Pegg, Mark (advisor)
Unit Nebraska Cooperative Fish and Wildlife Research Unit
Email mpegg2@unl.edu
Phone 402-472-6824
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=739
Project Information
Title Catfish Population Dynamics in the Platte River, Nebraska
Other(s) Tony J. Barada, abarada2@unl.edu 
Description

Catfish angling is popular throughout the United States and catfish are the most sought after fish species in the Platte River. However, catfish management in the Platte River is minimal as little is known about current populations. The objective of this study was to determine the current status of channel catfish and flathead catfish populations in the central and lower Platte River. Specifically, the study evaluated population characteristics including relative abundance, size structure, condition, age, growth and mortality.

Channel catfish are much more abundant than flathead catfish in the Platte River. The current Platte River channel catfish population appears to be average, comparable to many Nebraska and Midwestern rivers. Population characteristics displayed considerable variation along the Platte River and some longitudinal patterns were evident. Channel catfish in the central Platte River had lower relative abundances, higher condition, greater size structure, faster growth and lower mortality compared to lower Platte River channel catfish. Key factors likely influencing differences in channel catfish population characteristics are prey availability, flow modifications, habitat characteristics, tributary inflows and angler exploitation. Water manipulations from the Loup River Power Canal were also identified as a possible negative influence on lower Platte River channel catfish populations because hydropeaking is likely creating a stressful environment. However, channel catfish in the central Platte River appear to have benefited from recent high flows that likely increased productivity and food availability in the central Platte River.

Tony Barada's Master's Thesis on Catfish Population Dynamics in the Platte River

Project Support Nebraska Game and Parks Commission, Federal Aid in Sportfish Restoration
Project Website
Report
Current Status Graduate thesis project completed - thesis available at UNL CY Thompson Library (Call # LD3656 2009 .B373)
Topic Wildlife
Project's Primary Contact Information
Name Pope, Kevin
Unit Nebraska Cooperative Fish and Wildlife Research Unit
Email kpope2@unl.edu
Phone 402-472-7028
Web Page http://snr.unl.edu/aboutus/who/people/faculty-member.asp?pid=759
Project Information
Title Population Assessment of Channel Catfish in Nebraska
Other(s) Lindsey Chizinski, Graduate Assistant 
Description

Channel catfish (Ictalurus punctatus) is an important sport fish, particularly in the Great Plains. In Nebraska, a majority of anglers target channel catfish, and fishing activities are a vital part of the state’s economy. Lentic water bodies provide the primary fishing opportunity for catfish anglers in Nebraska. Despite the popularity and economic importance of channel catfish, little is known of its population dynamics or habitat requirements, and existing studies often profile river populations.

Current standards for sampling channel catfish in lentic systems often yield inadequate catch to assess populations. The objective of this study was to utilize a recently developed sampling method, tandem-set hoop nets, to collect channel catfish in sufficient quantities to describe the effects of stocking and habitat variability on populations in lentic ecosystems. Three lentic ecosystems common to the Great Plains were considered: sand pits, flood-control reservoirs, and irrigation/power-generation reservoirs.

The influence of stocking on abundance and condition of channel catfish varied with ecosystem type. In sand pits, stocking negatively influenced fish condition, and only stocking on an annual basis positively influenced abundance. In flood-control reservoirs, stocking did not influence fish condition, but was associated with greater abundance. In irrigation/power-generation reservoirs, stocking did not influence fish condition or abundance. Additionally, there was evidence that mortality and growth rates varied with ecosystem type. In general, channel catfish from irrigation/power-generation reservoirs were predicted to experience slower growth and lower mortality, whereas channel catfish from sand pits were predicted to experience the fastest growth and highest mortality.

Catch rates of channel catfish were substantially less in this study compared to previous records of tandem-set hoop net surveys, but hoop nets were more efficient than the current standard gear, experimental gill nets, at capturing channel catfish. That is, 100 channel catfish could be captured with fewer sets of hoop nets than gill nets. However, catch rates and size structure of channel catfish in tandem-set hoop nets varied within the sampling season and between years. Furthermore, length-frequency distributions of channel catfish were dissimilar between hoop nets and gill nets.

Click here to read Lindsey Chizinski's Master's Thesis on Channel Catfish Population in Nebraska

Project Support Nebraska Game and Parks Commission
Project Website http://snr.unl.edu/necoopunit/research.main.html#channel_catfish
Report
Current Status Completed
Topic Wildlife
Project's Primary Contact Information
Name Vivian, Lindsay A.
Unit Biology, UNK
Email lindsayviv@gmail.com
Phone 308-379-4587
Web Page
Project Information
Title Updating the Distribution and Population Status of the Platte River Caddisfly
Other(s) W. Wyatt Hoback, Biology UNK, hobackww@unk.edu 
Description The Platte River caddisfly, Ironoquia plattensis, was first described in 1999 from a warm water slough just south of Grand Island, NE. Using a benthic core sampling method, the investigators reported an average caddisfly larval density of 805 ± 194/m2. In 2004, there were no Platte River caddisflies observed at the 1999 study site. Ironoquia plattensis has been observed at five other locations in the central Platte region, but only two of the six historic populations are considered stable. Between 2002 and 2005, central Nebraska suffered an extensive drought, which could have taken its toll on the caddisfly. The sloughs where Ironoquia plattensis occur are typically wet nine months out of the year and dry during the summer. During the summer of 2009, four historic sites and one new, previously unrecorded site were sampled for larvae using a 30 cm D-frame net to sample a one meter swath a minimum of four times from each location. Using a GIS (Geographic Information Systems) predictive model and Google Earth, additional areas are being surveyed for the presence of the Platte River Caddisfly. The GIS model was created using local groundwater data from 1999 to the present, a soils layer, high resolution imagery, and a vegetation map analysis. If more populations are found, transects will be set up on the slough banks, and a quadrat will be used to quantify larval abundance in these areas. This will also be done at all historic locations. The goal is to establish the population status of this very rare insect of Nebraska which is adapted to the seasonal flows of the Platte River.

Lindsay Vivian's Master's Thesis on Platte River Caddisfly

For more information, read this journal article in the Annals of the Entomological Society of America

Project Support US Fish and Wildlife Service
Project Website
Report
Current Status In progress
Topic Wildlife
Project's Primary Contact Information
Name Young, Chelsey
Unit Biology, UNK
Email youngca2@unk.edu
Phone 507-469-8284
Web Page
Project Information
Title A range-wide assessment of plains topminnow (Fundulus sciadicus) distribution and potential threats
Other(s) W. Wyatt Hoback, Biology UNK, hobackww@unk.edu; Keith Koupal, Biology UNK; Justin Haas 
Description The plains topminnow, Fundulus sciadicus, was once distributed from the Mississippi River to the Rocky Mountains, north to South Dakota and as far south as Oklahoma. Two centers of distribution are recognized. One is centered in Nebraska and the second is centered in Missouri. The geographic range of plains topminnow has decreased in the past decades. Plains topminnow are now considered a species of special concern in the state of Nebraska and listed as a Tier 1 species in the Nebraska Natural Legacy Project. Elimination of plains topminnow populations has been associated with introduction of invasive species, as well as loss of backwater habitats due to drought and lowered water tables. The objective of this project is to provide an updated assessment of plains topminnow distribution and population status as compared to all available historical records. Between 2004 and the present, sampling of plains topminnow revealed that in Nebraska 77% of historic Nebraska sites no longer contain plains topminnow populations. The sampling of remaining historic sites in Nebraska and neighboring states will continue in the 2009 sampling season.
Project Support n/a
Project Website
Report topminnow_range_reduction.pdf
Current Status Completed