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NCSU Water Quality Group |
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Brown & Rock Counties
MLRA: G-66
HUC: 101500-04
The watershed is drained by Long Pine Creek, the longest self-sustaining trout stream in Nebraska. Relic populations of three species of fish threatened in Nebraska can be found in Long Pine Creek and its tributaries. The Long Pine State Recreation Area, a state park within the project area, is used by over 8,500 people each season, primarily for contact recreation and fishing.
Sediment, bacteria, and nutrients are the primary surface water pollutants impairing contact recreation and fishing on Long Pine Creek. There is potential for degradation of ground water quality from nitrate and pesticide contamination from commercial fertilizers and pesticides.
The primary sources of sediment are from intensive grazing in riparian areas, streambank erosion, and irrigation return flows. Specifically, excessive erosion occurs in the headwaters of Long Pine Creek due to intensive grazing in riparian areas, streambank erosion, and head cutting at the stream's source. Sand Draw and Bone Creek deliver excessive sediment load, warmer water, high fecal coliform, and fluctuating flow to lower Long Pine Creek. The sediment from Sand Draw is primarily from irrigation wasteway discharges and return flows. Excessive erosion occurs along unprotected streambanks and adjacent gullies at the mid-reaches of Bone Creek. Point source feedlots and the Ainsworth sewage treatment plant contribute to high bacteria and nutrient loadings in these tributaries. The water quality monitoring identified the priority subwatersheds of Sand Draw and Bone Creek for best management practice (BMP) emphasis.
The primary water quality goal was to improve the beneficial use of ground and surface waters. Critical area (60,242 acres) criteria were based on high erosion rates and proximity to waterways. Rural Clean Water Program (RCWP) contracts were written on 71% of the critical area. Not all BMP implementation is complete.
The project, which will continue until 1995, is currently emphasizing a system of erosion control and stream protection BMPs. Irrigation water management is used to minimize the total water usage, thereby reducing pollutants entering the streams and ground water. The major components used for irrigation water management were the installation of irrigation tailwater recovery (re-use) systems and the construction of a secondary storage reservoir. This reservoir was completed in September of 1987 using pooled funds from 10 RCWP coop erators. The reservoir reduces the volume of irrigation water use by 2,000 acre-feet annually and, therefore, reduces the amount of irrigation waste water and associated sediment delivered to the creeks by as much as 28,000 tons of sediment per year.
Stream protection using cedar revetments was one of the most innovative and successful practices implemented under the RCWP. As of April, 1991, 19,000 feet of revetments had been constructed. Combined with grazing land protection and fencing, the revetments successfully decreased streambank erosion and provided habitat for trout and other wildlife.
The strong information and education (I&E) component of the project resulted in reduced fertilizer and pesticide use, addressing both ground and surface water pollution simultaneously.
Surface water quality of Long Pine Creek has visually improved. Biological, habitat, chemical, and physical monitoring are being used to monitor fish habitat in streams and demonstrate improvements in recreational fishing in Long Pine Creek. Installation of stream protection measures have improved the instream trout habitat. Nebraska Game and Parks Commission (NGPC) and Soil Conservation Service (SCS) staff estimate that the mean carrying capacity of Long Pine Creek has increased from about 75 pounds per acre to about 119 lb/acre, a 58% increase.
Ground water was monitored annually from 1982 and will continue until 1994. The presence of high nitrate concentrations in both irrigation and domestic wells has been documented. About 5-10% of the samples were above the drinking water standard of 10 mg/l. Low levels of atrazine were found in one to two wells per year.
Both surface and ground water were monitored before and after BMP implementation. Pre-BMP surface water quality monitoring was performed from 1979 through 1985 to provide baseline data. A three-year post-BMP monitoring phase began in the fall of 1992 for the surface water. Dedicated monitoring wells will be installed in 1993 to sample ground water. Data will be compared with the pre-implementation data in order to evaluate BMP effectiveness on subwatershed and project level scales.
Figure 4.14: Long Pine Creek (Nebraska) RCWP project map, NE-1.
The project suffered at the beginning because agreement on land treatment and water quality goals could not be reached at the local or the state levels. Some project-level personnel wanted to build large water retention structures, while others wanted to emphasize on-site erosion control BMPs. The latter was more in line with the objectives of the RCWP and was established as the primary project goal in the mid-1980's.
Pre-implementation water quality data should be utilized to establish critical areas contributing to the water quality problems.
Well-defined quantitative goals need to be established for water quality and land treatment.
Land treatment goals should be directly linked to the water quality goals. These goals should include the identification of priority areas for land treatment.
Water quality monitoring objectives should be quantitative and realistic. The amount of change expected to measure in each primary water quality variable should be stated as part of the monitoring objective. The monitored water quality variables should be directly related to the water quality use impairment. The project team should keep in mind that there may be a lag time between BMP implementation and observed water quality improvements, especially in ground water.
The LCC formed three subcommittees which contributed to project success. The Executive committee provided administrative support and coordinated BMP development. The Technical Action Committee (TAC) developed the technical assistance, monitoring and evaluation, and project strategy portions of the Annual Plan of Work. The TAC also helped develop BMPs and a technical assistance priority system for treating water quality problem areas. The Information and Education (I&E) subcommittee developed the I&E portion of the Annual Work Plan and conducted I&E activities, including field tours and demonstration projects and media coverage.
This project suffered at times from inadequate communication between the Local Coordinating Committee (LCC) and the State Coordinating Committee (SCC). The goals of the RCWP were initially misinterpreted by some of the local project personnel.
The local project personnel finally established realistic land treatment goals and formulated and implemented a successful project.
The project would have been strengthened by early dedication of ASCS and SCS personnel to the RCWP project and by a designated full-time local project coordinator.
Clear, pre-project agreements must be established regarding agency roles, the water quality problem, critical area delineation, water quality and land treatment goals, and land treatment strategy in order for the LCC and the project participants to achieve project objectives and goals.
Priorities based on water quality objectives should be established for specific BMPs and Subbasins.
The SCC should create a Technical Committee who could evaluate the technical aspects of innovative and new practices recommended by the LCC.
To improve communication between the SCC and the LCC, at least one member of the SCC should attend the LCC meetings.
Funds should be available to encourage continued maintenance of BMPs.
A strong I&E program resulted in reduced fertilizer and pesticide use, addressing both ground and surface water pollution simultaneously.
Fertilizer management, demonstrated through CES workshops and a 50-acre demonstration farm, was widely adopted as producers realized they could save $10 to $40 per acre by reducing application rates from 220 pounds/acre to 170-180 pounds/acre without sacrificing yields.
In Nebraska, an Integrated Pest Management (IPM) association was formed by farmers to provide weekly pest scouting for all members. The association published a newsletter through the CES and broadcast a radio program on insect activity. These efforts supported the pesticide management component of the project's I&E program.
The Cooperative Extension Service was a valuable resource for this project.
Field demonstrations can be a powerful tool for communicating the effectiveness of BMPs with producers.
Technical funds need to be allocated for I&E activities.
Lack of a feeling of ownership of the off-site water quality problem by producers and lack of clear land treatment strategies hindered participation during the first four years of the project.
The most important reason farmers decided to participate was availability of cost share funds. Increased farm production was given as the second most important reason.
RCWP cost share improvements to feedlots were not approved because they are considered point sources under state regulation.
The most important reasons farmers decided not to participate were economic conditions and costs. Not wanting to be told how to farm was given as the second most important reason.
The ground and surface water monitoring program used in this project aided in prioritizing the critical area portions of the watershed.
Land treatment implementation was slow due to unclear water quality and land treatment goals, problem definition, critical area definition, and implementation strategies. Implementation was initiated in 1984.
Emphasis on fertilizer and pesticide management is a key factor in dealing with ground and surface water problems simultaneously.
Cedar revetments utilized for streambank stabilization were one of the most innovative and successful practices implemented under the RCWP. As of April, 1991, 19,000 feet of revetments had been constructed for streambank erosion. These revetments also provide a variety of habitat benefits for trout and other aquatic life. The trout carrying capacity of Long Pine Creek has increased as a result of the revetments and associated habitat improvements.
Approximately 68% of all cost share funds were spent on irrigation and water management. For example, almost 22% of the funds were used for the Ainsworth Irrigation District secondary storage structure. The rest centered on tailwater recovery and water control structures. By collecting irrigation runoff, sediment and chemicals were prevented from entering surface waters. The water collected was then reused. This recycling of runoff saved energy and dollars in addition to reducing the amount of sediment entering streams.
Grazing land protection received approximately 12% of the cost share funds. Fencing to exclude cattle from streambanks, in combination with providing alternative water supplies, became more acceptable to the farmers after they recognized that the fencing would limit, but not preclude, stream access and that the effective grazing acreage would increase because animals would be using the entire pasture, not just the riparian areas. To increase the atrractiveness of grazing land protection strategies, the windmills and pumps used to provide alternative water sources were cost shared.
Although streambank stabilization was addressed, the high priority areas of Sand Draw and Bone Creek did not receive sufficient revetments and other stabilization practices to completely address the major water quality problems.
Through the use of deep soil sampling to enhance fertilizer recommendations and irrigation scheduling, fertilizer use was greatly reduced throughout the watershed.
Fertilizer and pesticide management were widely adopted outside the critical area.
An Integrated Pest Management (IPM) Association was formed to provide field scouting, with the result that pesticide use was significantly reduced.
Improvements to both the Ainsworth and Long Pine sewage treatment plants have occurred so that the plants now comply with USEPA and state standards.
Feedlots continue to contribute pollutants to Long Pine Creek. Opportunities exist to reduce fertilizer use by transferring manure from large feedlots to RCWP-participating farms. RCWP cost share was not available for feedlot improvement due to the classification of feedlots with greater than 1,000 units as point sources under Nebraska law.
Procedures for documenting land treatment / land use and cost share information need to be clearly defined at the beginning of the project. The data bases created should be on a subwatershed drainage scale such that they can be linked with the water quality data base. A data log with RCWP contract, subbasin number, BMP, practice code, critical acres served, units applied, date BMP effective, crop, soil loss savings, water saved, installation costs, and cost share should be recorded as cost-share payments are made. This will facilitate the annual summary of land treatment and land use.
The reporting of "acres served" and "units" applied need to be consistent over time.
The surface and ground water samples reported for 1979 to 1985 were considered pre-implementation or baseline data. Analysis of baseline data identified impaired beneficial uses and helped in targeting location and type of needed BMPs. The pre-BMP water quality monitoring identified the priority subwatersheds of Sand Draw and Bone Creek for BMP emphasis. Based on the water quality results, it was recommended that emphasis be placed on installation of streambank protection and habitat improvement structures in the upper reaches of Long Pine Creek. Emphasis of BMPs which reduce the delivery of runoff into streams was also recommended.
This project has an extensive biological and habitat monitoring design which helped document use impairments.
Baseline data will serve as a comparison when the post- BMP implementation water quality analysis is performed.
The presence of high nitrate concentrations in both irrigation and domestic wells has been documented. About 5 to 10% of the samples were above the drinking water standard of 10 mg/l. A trend of increasing nitrate concentrations has been identified in some irrigation wells. No significant trend was observed in the domestic wells. The irrigation wells are a better source of regional aquifer water quality information compared to domestic wells; however, local contamination may still be a concern. Chemical accidents may have caused high levels of nitrate-N in some wells.
Low levels of atrazine (about 0.1-0.2 part per billion, ppb) were found in one to two wells per year. Trifluralin, alachlor, cyanide, and metolachlor have also been detected in a few samples.
Ground water trend analysis was difficult in most cases because different wells were sampled in different years. Most wells were sampled in two to five years. Only 5 wells were sampled 8 years. Attempts to sample each irrigation well annually were hampered by wells taken out of use by land enrolled in the CRP or set-aside programs, rainy weather, and irrigation rotation timing.
Surface water sampling was discontinued in 1985 at most stations, but was reinstated for 1992-1994. This break in the time series record decreases the potential to clearly demonstrate water quality improvements.
Weekly or biweekly sampling may be better than monthly sampling to increase the number of observations and account for a greater amount of natural variability, thereby increasing the ability to detect changes in water quality.
Use of dedicated monitoring wells is preferable to use of domestic and irrigation wells for monitoring ground water. Use of newly constructed dedicated wells minimizes the potential for local contamination and increases the chances that the wells will be available for monitoring throughout the project period. There is a need for sufficient information about the sampled wells and site-specific information to determine if the nitrate- or atrazine- contaminated wells are responding to local sources of contamination or represent general aquifer conditions.
Installation of stream protection measures has improved the instream trout habitat and may have increased the trout carrying capacity of Long Pine Creek. Using site-specific evaluations, the project NGPC and SCS staff estimate that the mean carrying capacity of Long Pine Creek has increased from about 75 lb/acre to about 119 lb/acre, a 58% increase (Hermsmeyer et al., 1991). Installing cedar revetments in combination with broadcasting or sodding reed canary grass decreased streambank erosion and flushing out of deposited sand. This resulted in re-exposure of the gravel bed, increased stream velocity, increased stream depth, decreased channel width, and increased spawning habitat.
The project has estimated significant reductions in pesticide and fertilizer use, but does not have an estimate on the corresponding impact on ground water quality. There may be a lag of several years before a measurable impact on ground water quality is observed.
The project has not completed its post-BMP monitoring. Analysis of the water quality and land treatment data will occur in 1995.
The project has a long pre-BMP monitoring record (five years) with both chemical and biological data. Three years of post-BMP monitoring data is planned. Some upstream-downstream site pairs are located in the tributaries. The length of the monitoring record and a high level of land treatment in the critical area provide the potential for documenting the effectiveness of irrigation water management, nutrient management, and streambank stabilization (cedar revetments and reduced riparian grazing) over a 10-year time frame. However, the influx of sediment from headcut erosion may reduce the ability to document BMP effectiveness.
The important explanatory variables of stream flow and rainfall were measured concurrently with water quality sampling. This should increase the project's ability to isolate water quality changes due to BMPs and climatic variability.
The project has documented annual land treatment and some of the land use changes on a subwatershed scale, which should facilitate the analysis. The Nebraska project took the initiative to revise their land treatment data base near the end of the project period in order to more effectively link their land treatment and water quality data bases (Hermsmeyer et al., 1991).
Creation of the land treatment data base after BMP implementation required a lot of effort and some useful information has been lost. Until 1992, there were no detailed procedures established for the collection of land treatment data on a subbasin basis. Delineation of subbasins, as defined by the land drained to the water quality monitoring stations at the tributary outlets, were not utilized to identify land treatment subbasins during the implementation period. In addition, consistent reporting procedures were not utilized for identifying critical acres and acres served. Reconstruction of the ASCS and SCS files that quantified BMP implementation in the critical acres on a subbasin and annual basis was required by the project.
Variations due to seasons and changes in flow need to be measured and incorporated into analyses to allow for valid interpretations on water quality trends. Additional hydrologic and meteorologic variables such as precipitation, storm intensity and frequency, stream flow, and ground water table depth should be measured if related to water quality in the project.
Land treatment and land use information should be tracked by hydrologic (drainage) units to facilitate evaluation of BMP effectiveness. Procedures for documenting critical areas, subbasin delineations, land use, and land treatment data must be established at the projects' beginning. Consistent reporting and a data base should be maintained seasonally or at least annually.
Land use and land treatment within the project area for both participants and non-participants should be tracked in the land treatment data base. Land treatment data tracking should not end with contract expiration if the practice is still being maintained.
Significant changes in annual land use should be incorporated into the analysis to allow valid interpretations to be made regarding water quality changes due to the BMPs and other land use changes. Land use activities that are important to track include cropping patterns, tillage methods, irrigation frequencies, rate and timing of chemical applications, and acres in set-aside programs.
1981 - 1995
Surface water: Long Pine Creek (drainage = 293,100 acres, average aggregate flow = 150 cubic feet per second (cfs) at mouth); major tributaries are Bone Creek, Sand Draw, and Willow Creek.
The project area rests upon the High Plains Aquifer that extends south through Kansas and Oklahoma into Texas.
Ground water: Ground water is used for irrigation, stock watering, and domestic and municipal water supply throughout the project area. The source of ground water is the Great Plains Aquifer. There is potential for degradation of the drinking water supply from nitrate and pesticide contamination.
Improve the beneficial uses of ground and surface waters in the project area, including domestic, agricultural, industrial, recreational, and cold-water fisheries
Plan, implement, and evaluate BMPs that have been selected to improve water quality and beneficial uses of water in the project area
Demonstrate the water quality effects of nutrient and pesticide management, irrigation water management, and streambank stabilization as BMPs for surface and ground water protection
Educate the general public about the importance of water quality
Develop positive community attitudes toward the importance of water quality
Geologic Factors: The watershed is underlain by shale and sand stone. Topography is diverse, ranging from nearly level to steep. Most of the watershed is covered by a blanket of eolian sand material. Soils are predominantly silts and sands.
Use % of Project Area % of Critical Area Cropland (corn and alfalfa): NA 18 Pasture/range: NA 81 Woodland: NA - Urban/roads: NA 1
Operation # Farms Total # Total Animal
Animals Units
Dairy 3 140 196
Beef 12 25,500 25,500
Hogs 5 1800 720
SOURCES Federal State Farmer Other ACTIVITY SUM Cost Share 857,540 0 265,069 0 1,122,609 Info. and Ed. 230,605 0 0 0 230,605 Tech. Asst. 422,659 0 0 0 422,659 Water Quality Monitoring 300,000 297,850 0 0 597,850 SUM 1,810,804 297,850 265,069 0 2,373,723Source: Hermsmeyer et al., 1991
The CES took the lead role in developing and implementing the I&E components of this project. SCS assisted with the development water quality plans and by providing technical assistance.
Educate the general public about the importance of water quality
Coordinate project-related information flow between federal, state, and local agencies
Support and encourage implementation of appropriate BMPs outside the project area
Promote a good working relationship between the local agricultural community and state and federal agencies involved in the RCWP
RCWP quarterly newsletter entitled "Long Pine Rural Clean Water Program Newsletter"
Field tours and demonstrations to study the effectiveness of fertilizer, pesticide, liming, and water management. The CES used a 50-acre demonstration farm to display and test and demonstrate these BMPs.
Survey of land users' attitudes about the effectiveness of the I&E program and the RCWP
Secure adequate media coverage, including the production and viewing of three videotapes, two of which appeared on Nebraska Public Television.
An Integrated Pest Management (IPM) Association was formed in 1983 and provided field scouting, a IPM newsletter, IPM training sessions in identification of pests, weather and soil temperature reports, alerts to potential insect problems, and recommended application methods and rates of herbicides and pesticides.
Payment Limitations: $50,000 per farmer
Availability of cost share funds
Perception that increased farm production would result from implementation of RCWP BMPs
Fertilizer management, demonstrated through CES workshops and demonstrations, was widely adopted as producers realized they could save $10 to $40 per acre without sacrificing yields.
The project had applied to have a one million dollar sediment structure built on Sand Draw. The structure was never funded because the project could not demonstrate the on-farm water quality benefits and justify expenditure of RCWP funds. After denial of the structure was final, the project concentrated on irrigation water management and streambank stabilization.
Roadside Critical Area Treatments (CAT) were installed to reduce roadside erosion in the project area. These were not funded under RCWP, but by the North Central Nebraska Resource Conservation and Development USDA program through SCS, MNNRD, and Brown County.
Reduce the delivery of sediment from agricultural lands
Reduce the deep percolation of irrigation water contaminated with fertilizers and pesticides
Reduce excess irrigation water runoff
Reduce agricultural NPS pollution from feedlots
Quantified Implementation Goals: 75% of the critical areas
Streambanks or gullies with active erosion
Center pivot irrigated cropland with greater than 5T/acre/year soil loss
Rangeland in poor or fair condition
Application of Criteria: Contracts were primarily being applied to the critical areas; however, little priority was given to the order or selection of BMPs.
Permanent vegetative cover (BMP 1)
Animal waste management system (BMP 2)
Diversion system (BMP 5)
Grazing Land Protection (BMP 6)
Waterway system (BMP 7)
Cropland protection system (BMP 8)
Conservation tillage system (BMP 9)
Stream protection system (BMP 10)
Permanent vegetative cover on critical areas (BMP 11)
Sediment retention, erosion, or water control structures (BMP 12)
Improving irrigation system and / or water management system (BMP 13)
Tree Planting (BMP 14)
Fertilizer Management (BMP 15)
Pesticide Management (BMP 16)
*Please refer to Appendix I for description/purpose of
BMPs
Procedures for consistent documentation of land treatment / land use and cost share information were not clearly defined at the project beginning. These data bases should be maintained on a subwatershed drainage scale so that they can be linked with the water quality data base. Consistent definitions for critical acres and acres served were not established at the project initiation, making compilation of acres served in each subbasin by year difficult.
The Ainsworth irrigation district secondary storage reservoir, upstream of 33,000 acres of irrigated cropland, was completed in September of 1987 using pooled funds from 10 RCWP cooperators. The reservoir reduces the volume of irrigation water applied by an estimated 2,000 acre-feet annually for gravity-irrigated cropland in the critical area, and therefore, reduces the amount of irrigation waste water and associated sediment delivered to the creeks by as much as 28,000 tons of sediment per year.
Stream protection using cedar revetments was one of the most innovative and successful practices implemented under the RCWP. As of April, 1991, 19,000 feet of revetments had been constructed. Combined with grazing land protection and fencing, the revetments successfully decreased streambank erosion and provided habitat for trout and other wildlife. Project personnel developed several innovations to overcome difficulties in implementing cedar revetments. To prevent beaver damage, the cedar trees had to be cut and dried up to a year before use. Reed canarygrass seed was broadcast or placed as sod on top of sediments trapped by the revetments to prevent damage by heavy rains and runoff.
Over half of all cost share funds were spent on irrigation and water management; 21.8% was for the Ainsworth Irrigation District secondary storage structure. The rest centered on tailwater recovery. Sediment and chemicals were prevented from entering surface waters when the irrigation runoff was collected and then reused. This recycling of runoff saved energy and dollars in addition to reducing the amount of sediment entering streams.
The small sediment control dams constructed under BMPs were more cost-effective than the cost of the large structure that was not approved for Sand Draw.
The MNNRD's drop structure is attempting to address the headcutting in Long Pine Creek.
Fertilizer and pesticide management were widely adopted outside the critical area. As a result of deep soil sampling and irrigation scheduling, fertilizer use was greatly reduced throughout the watershed.
An Integrated Pest Management (IPM) Association involving field scouting resulted in a large reduction in pesticide use.
Improvements to both the Ainsworth and Long Pine sewage treatment plants have occurred so that the plants now comply with USEPA and state standards.
Feedlots continue to contribute pollutants to Long Pine Creek. Opportunities exist to reduce fertilizer use by transferring manure from large feedlots (defined by the state as point sources) to RCWP-participating farms. RCWP cost share was not available for feed lot improvement due to the classification of feedlots with greater than 1,000 units as point sources under Nebraska law.
Streambank erosion continues to be a problem in Sand Draw and Bone Creek.
Quantified Project Achievements:
Pollutant Critical Area Source Units Total % Implemented Cropland acres 11,000 71%* Pasture acres 49,242 71% Dairies #farms 2 100% Feedlots # 2 100% Contracts # 86 98%* Contracts were written on 71% of critical area.
Water quality monitoring was performed by the NDEC with the assistance of SCS, NGPC, CES, MNNRD.
Document the magnitude of surface and ground water quality problems
Demonstrate the water quality effects of nutrient and pesticide management, irrigation water management, and streambank stabilization as BMPs for surface and ground water protection
Pre-BMP Implementation Monitoring Goals:
Document pre-BMP water quality conditions
Identify existing water quality problems, including any areas where surface-water-quality-dependent beneficial uses are impaired by land use activities
Identify and prioritize areas where BMP installation will have the greatest effect
Provide baseline data for evaluation of site-specific BMPs and changes in water quality
Post-BMP Implementation Monitoring Goals:
Determine if there is any change in ambient surface water quality from pre-implementation conditions in Long Pine Creek, Bone Creek, Sand Draw, and Willow Creek
Determine if a primary contact recreation use is attainable on the lower reaches of Bone Creek based on the physical conditions and current public utilization of the stream
Determine the frequency of water quality criteria violations and the level at which the appropriate beneficial uses are supported in streams within the project area
Determine at what level salmonid spawning is currently supported in Long Pine and lower Bone Creeks based on embryo survival in artificial redds
Determine if the macroinvertebrate population (i.e., taxa present, frequency of occurrence, number of individuals, diversity, and pollution tolerance) in Long Pine and Bone Creeks has significantly changed from pre-implementation conditions due to the implementation of BMPs
Determine if the fishery population (i.e., taxa present, frequency of occurrence, diversity, and pollution tolerance) in Long Pine Creek, Bone Creek, and Sand Draw has significantly changed from pre- implementation conditions due to the implementation of BMPs
Determine if the salmonid population (i.e., standing crop, size class composition, and condition factors) in Long Pine Creek has improved from pre-implementation levels due to the implementation of BMPs
Determine if the project implemented by the MNNRD to control headcutting in the upper reaches of Long Pine Creek is effective in reducing sediment delivery from this source
Determine the combined effect of implementing BMPs (cedar revetments, other streambank stabilization measures, and control of headcutting) on fishery habitat and sediment delivery in upper Long Pine Creek
Determine the change in trends in the suspended solids, substrate composition, and bacterial levels in Long Pine Creek due to the implementation of BMPs and feedlot controls
Determine if summer water temperature and instream habitat still restrict the potential for cold water fisheries in the lower reaches of Long Pine Creek
Determine the change in trends in suspended solids, substrate composition, bacteria, nutrients, organic waste, and water temperature in Bone Creek due to the implementation of BMPs and feedlot controls
Determine the change in trends in suspended solids, substrate composition, and water temperature in Sand Draw due to the implementation of BMPs
Ground Water: 1982 - 1994
Ground Water: Varying numbers and locations of irrigation and domestic wells were sampled each year (approximately 4-20 of each well type) from a total of 67 different wells.
Streambank erosion: 4 sites to evaluate the magnitude of erosion reduction effectiveness of cedar revetments and upstream movement of the headcut
Flow actuated automatic samplers for runoff sampling
Ground Water: annually in July or August when the aquifer is used for irrigation / Each well was sampled 1 to 8 times over the project period.
Streambank erosion sites: annually
During the post-BMP monitoring period, a recreational use attainability study on lower Bone Creek near the State Recreational Area will be conducted.
Both surface and ground water monitoring data are stored in STORET. The biological data have been entered into BIOS, a companion data base to STORET. The BIOS agency and station codes are the same as those used for STORET. For a description of the biological variables measured at each station, see Maret (1985).
STORET STORET PROFILE
AGENCY CODE STATION NO. MAP / STATION NO
Surface Water Monitoring Stations
21NEB001 LP0001 NE-1 / LP1
" LP0005 NE-1 / LP5
" LP0007 NE-1 / LP7
" LP0008 NE-1 / LP8
" BN0000 NE-1 / BN
" BN0001 NE-1 / BN1
" BN0002 NE-1 / BN2
" BN0003 NE-1 / BN3
" SD0001 NE-1 / SD1
" SD0002 NE-1 / SD2
21NEB001 W0001 NE-1 / W1
" LPR001 NE-1 / Rainfall collected near LP1
" LPR007 NE-1 / Rainfall collected near LP7
" LPR008 NE-1 / Rainfall collected near LP8
" BNR001 NE-1 / Rainfall collected near BN1
" BNR003 NE-1 / Rainfall collected near BN3
" SDR02B NE-1 / Rainfall collected near SD2
The STORET agency code is 21NEAGO1. The STORET station code is
of the form "LPGWnn" where `nn' is the well number. The RCWP
project has wells 1 through 64 with this naming convention.
There are 3 Health Department wells that are used in the RCWP
reports, but these wells are not in STORET.Exploratory data analysis includes tabular presentation of the data, time plots, and calculation of minimum, means, medians, maximums, and standard deviations for water quality concentrations at each site over the pre- implementation period.
Water quality index values are calculated using weighted values of DO, pH, NO3-N, NH3-N, suspended solids, and conductivity. Species diversity and biotic indices were calculated with macroinvertebrate data.
Surface water quality data are compared to the Nebraska Surface Water Quality Standards.
After the post-BMP monitoring is complete, the project plans additional analyses including:
Surface water quality of Long Pine Creek has visually improved, especially below the confluence with Bone Creek.
The surface and ground water samples reported for 1979 to 1985 were considered pre-implementation or baseline data. Analysis of baseline data identified impaired beneficial uses and helped in targeting the locations and types of needed BMPs.
The pre-BMP water quality monitoring identified the priority subwatersheds of Sand Draw and Bone Creek for BMP emphasis. Based on the water quality results, it was recommended that emphasize be placed on installation of streambank protection and habitat improvement structures in the upper reaches of Long Pine Creek. Emphasis of BMPs which reduce the delivery of runoff into streams was also recommended.
Baseline water quality data will serve as a comparison when the post-BMP implementation water quality analysis is performed (Maret, 1985).
Recreational use in the project area has been steady since 1976. Fishing in the project area continues to be impaired by high sediment levels.
The presence of high nitrate concentrations in both irrigation and domestic wells has been documented. About 10% of the samples were above the drinking water standard of 10 mg/l. A trend of increasing nitrate concentrations has been identified in some irrigation wells. No significant trend was observed in the domestic wells. The irrigation wells are a better source of regional water quality information compared to domestic wells; however, local contamination may still be a concern. Chemical accidents may have caused high levels of nitrate-N in some wells.
Low levels of atrazine (about 0.1-0.2 ppb) were found in one to two wells per year. Trifluralin, alachlor, cyanide, and metolachlor have also been detected in a few samples.
Installation of stream protection measures has improved the instream trout habitat and may have increased the trout carrying capacity of Long Pine Creek. Using site-specific evaluations, the project NGPC and SCS staff estimate that the mean carrying capacity of Long Pine Creek has increased from about 75 lb/acre to about 119 lb/acre, a 58% increase (Hermsmeyer et al., 1991).
The project has estimated significant reductions in pesticide and fertilizer use, but does not have an estimate on the corresponding impact on ground water quality. The lag time for a measurable response in the ground water may be years.
The project has not completed its post-BMP monitoring. Analysis of the water quality and land treatment data will occur in 1995.
Changes in annual land use were significant and need to be incorporated into the final analysis to allow valid interpretations to be made.
The project has documented land treatment changes on a subwatershed scale which should facilitate the analysis. The Nebraska project took the initiative to revise their land treatment data base near the end of the projects in order to more effectively link their land treatment and water quality data bases. This after-the-fact data base creation required a lot of effort and some useful information was lost. The project had no consistent procedure established for the collection of land treatment data on a subbasin basis that would allow the land treatment information to be directly linked to the water quality monitoring. Delineation of subbasins, as defined by the land drained to the water quality monitoring stations at the tributary outlets, were not utilized during the implementation period for recording land treatment progress. In addition, consistent reporting procedures were not utilized for identifying critical acres and acres served. Reconstruction of the ASCS and SCS files that quantified BMP implementation in the critical acres on a subbasin and annual basis was required.
Documentation of non-RCWP land use changes and activities is sketchy.
However, the 1985 Farm Bill competed with the SCS personnel time available to implement the RCWP. The CRP program, Highly Erodible Land (HEL) identifications for each cropland field, conservation plan preparation, and the RCWP all competed with a limited amount of SCS staff time available.
Federal farm programs had a large effect on changes in annual land use. These federal programs are adjusted annually, based on grain stocks on hand. These programs changed annual acres in grain, the amount of chemicals applied to land, and the amount of water needed to irrigate cropland.
Nebraska law defines feedlots with over 1000 animal units as permitted point sources. Feedlots were not eligible for RCWP cost share.
Hermsmeyer, B., D. Jensen, and M. Link. 1991. Nebraska Long Pine Creek Rural Clean Water Program Ten Year Report 1981-1991. Brown County Agricultural Stabilization and Conservation Service (ASCS), Ainsworth, NE. 275p.
Maret, T. 1985. Water Quality in the Long Pine Rural Clean Water Project 1979-1985. Nebraska Department of Environmental Control, P.O. Box 94877 - Statehouse Station, Lincoln, NE. 194p.
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NCSU Water Quality Group |
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