Water: Nonpoint Source Success Stories
Idaho Section 319 Success Stories, Vol. III
NRCS District Conservationist
|Primary Sources of Pollution:|
|nonirrigated cropland (headwater sites)|
|rangeland (grazing activities)|
|surface mining operations|
|Primary NPS Pollutants:|
|high water temperature|
|streambank stabilization structures|
|20 tons per acre per year reduced erosion from erosion control structures|
|7 tons per acre per year reduction from sheet and rill erosion control practices|
|20 percent reduction in use of pesticides and fertilizers|
|increased trout density|
Hatwai Creek is 3 miles east of Lewiston, Idaho. Its watershed consists of 19,785 acres of cropland (56 percent), rangeland (31.5 percent), pasture/hayland (5 percent), riparian areas (2.5 percent), roads (2 percent), forestland (1 percent), mining (1 percent), and farms and suburban areas (1 percent). The watershed elevation ranges from 775 feet to 2,964 feet. Annual precipitation ranges from 10 inches at lower elevations to 22 inches at higher elevations.
The watershed was listed on Idaho's 303(d) list and also listed as critical habitat for steelhead salmon. The National Marine Fisheries Service (NMFS) listed steelhead as threatened in Hatwai Creek. The creek's beneficial uses are agriculture water supply, secondary contact recreation, and salmonid spawning. The nonpoint source pollutants include sediment, nutrients, and high water temperature. The primary sources of such pollutants are nonirrigated cropland (headwater sites), rangeland (grazing activities), surface mining operations, and streambank erosion.
Combined resources to address watershed
In the early 1990s the Nez Perce Soil and Water Conservation District (NPSWCD) organized local, state, and federal stakeholders to address water quality and fishery concerns. The watershed plan resulting from that partnership consisted of four separate projects to address water quality and fisheries issues: an EPA 319 project, a U.S. Department of Agriculture Water Quality Incentives Project, a riparian demonstration project funded by the Idaho Soil Conservation Commission, and a USDA Environmental Quality Incentives Program project.
The Idaho Department of Environmental Quality (DEQ) funded a sediment and nutrient reduction project through section 319 funding. The project included landowner education for watershed management and nonpoint source pollution. Many structural conservation practices were installed, including 12 water and sediment control basins, nine grade stabilization structures, two ponds, one off-site water development, eight sediment basins, 8,000 linear feet of terrace, and 5,400 linear feet of riparian improvement practices (brush mattresses, pole plantings, and revetments).
The USDA Water Quality Incentive Program project provided incentive payments for nutrient and pest management and for well testing. Thirty-five landowners participated and received training on soil testing, nutrient budgets, Integrated Pest Management practices, and wellhead protection practices. More than 11,000 acres were treated through this program.
The riparian demonstration project began in 1993 and will be completed in 2001. The primary areas of focus are grazing management on riparian and upland areas, enhancement of the riparian areas, streambank stabilization, and fish habitat improvement.
In June 1999 a special project for reducing sheet and rill erosion on cropland was initiated through the support of the Natural Resources Conservation Service's (NRCS) Environmental Quality Incentives Program. Conservation practices will focus on the implementation of direct seeding systems, a new technology for this area, and there is a possibility of reducing sheet and rill erosion by as much as 25 percent.
Success of cooperative efforts
The Idaho Department of Fish and Game collected fish data in Lower Hatwai Creek, monitoring the responses of wild trout, natural rainbow trout, and steelhead trout. Monitoring results for the 1995 to 1998 period indicate that the trout density increased annually throughout the length of the demonstration project. Trout density in the project area increased from 0.32 per 100 square meters in 1995 to a high of 13.24/100 m² in 1998; in the control area, on the other hand, trout density was only 0.87/100 m² in 1996, 3.00/100 m² in 1997, and 3.06/100 m² in 1998. This improvement is attributed to improved riparian health, including improved streambank, increased canopy cover, and decreased stream temperatures.
Nineteen erosion control structures were installed, reducing concentrated-flow erosion of sediment by an average of 20 tons per acre per year. Installing sheet and rill erosion control practices on 10,000 acres of nonirrigated cropland resulted in a reduction of 7 tons per acre per year. Installing 9,000 acres of pest and nutrient management practices produced a 20 percent reduction in the amount of pesticides and fertilizers applied.
The NPSWCD also completed a landowner survey to document technology adoption. Eighty-five percent of those surveyed had participated in at least one of the four projects, and 69 percent confirmed that they would participate again in a similar project if given the opportunity. Fifty-four percent of those surveyed were willing to participate in watershed advisory groups. Nineteen different types of conservation practices were installed on more than 14,000 acres of land, representing about three-fourths of the total watershed acreage.Success is the result of the cooperative efforts of landowners, the public, and various agencies. Groups assisting included DEQ, EPA, Idaho Department of Fish and Game, Idaho Soil Conservation Commission, Nez Perce County Commissioners, Lewiston Senior High School, Lewiston Retired Senior Volunteer Program, Idaho Department of Lands, Idaho Department of Water Resources, NRCS, University of Idaho, local Boy Scout groups, NMFS, and the NPSWCD.
Restoring the Paradise Creek Watershed:
Phased Approach Implemented to Address Pollution and Flooding
Palouse-Clearwater Environmental Institute
|Primary Sources of Pollution:|
|Primary NPS Pollutants:|
|remeander channel segments|
|revegetate riparian areas|
|conduct community education|
|projected decreases in sediment, nutrients, high temperatures|
|projected 1.5-foot drop in flood elevations|
Paradise Creek originates on Moscow Mountain (elev. 4,356 feet) and then flows in a southwesterly direction for 20 miles, through Moscow, Idaho (elev. 2,520 feet), ultimately entering the South Fork of the Palouse River in Pullman, Washington. The creek drains 34 square miles and consists of 55 stream segments, 49 of which flow through agricultural fields. Wetlands associated with riparian areas along Paradise Creek are in poor condition because of past and present management activities such as draining and tiling.
Today, Paradise Creek is a simplified ecosystem adversely affected by habitat destruction, excessive sediment, nutrients, high temperatures, altered flow, pathogens, and ammonia, which in combination have significantly decreased its biological integrity. Cropland is the most prevalent land use (about 73 percent) in the Paradise Creek watershed but provides the least diverse plant community type. Historically, Paradise Creek supported cold water fisheries; currently, the creek supports only limited nongame fish species. Because negative impacts on the stream continue to increase along with growth in the urban areas of Moscow and Pullman, it is becoming even more difficult for the creek to repair itself.
A multiphase approach
For the past decade, the Palouse-Clearwater Environmental Institute (PCEI), a 501(c)(3) nonprofit organization, has directed watershed restoration projects in Paradise Creek. From 1994 to the present, PCEI has led a seven-phase comprehensive watershed restoration approach in the Paradise Creek watershed. In addition to 319 funding, support for this project was provided by a multitude of partners, including Moscow School District No. 281; numerous private individuals and businesses; City of Moscow; Latah Soil and Water Conservation District; University of Idaho; Palouse Conservation District in Whitman County, Washington; City of Pullman, Washington; Idaho Department of Fish and Game; Idaho Department of Water Resources; Idaho Department of Lands, Soil Conservation Commission; U.S. Army Corps of Engineers; U.S. Department of Agriculture's Natural Resources Conservation Service; and U.S. Fish and Wildlife Service.
Phase 1 of the project began in fall 1995, and the project continues today with restoration efforts in Phase 7. Most of the activities have involved floodplain and wetland restoration, streambank stabilization and revegetation, and relocation of the previously straightened stream channel to its natural pattern in the Paradise Creek watershed. These efforts have involved the cooperation and participation of both public and private landowners along the Paradise Creek corridor, dealing with various contributors of nonpoint source pollution.
In 1995 Phase 1 began with the restoration of a floodplain and streambanks at a site owned by the Moscow School District. Before the restoration project, this section of Paradise Creek was channelized with unstable banks. The riparian zone was farmed, and plant diversity along the stream channel was low. Phase 1 involved efforts to remeander 1,200 feet of stream channel, as well as streambank stabilization practices, including the planting of more than 750 native plants on some 3,000 square feet of streambank and 5 acres of floodplain.
Also in 1995, the commencement of Phase 2 involved the development of wastewater treatment wetlands with the help of local community volunteers and students, who planted the newly constructed cells with 23,860 native herbaceous wetland plants. The wetlands were completed in 1998, and PCEI has given tours of the site to classes from universities and to local groups like the Native Plant Society.
In 1996 Phase 3 projects were aimed at floodplain restoration, streambank stabilization, and the remeandering of a 1,250-foot segment of the creek owned by the University of Idaho that had previously been channelized. The creek's path had been tamed, but it had little value for flood control, aesthetics, or wildlife. The floodplain was therefore revegetated with a native riparian plant community, and a sinuous, low-flow channel with bioengineered bank stabilization and habitat structures was constructed. In addition, biofilters, including grassy swales and "pocket" wetlands, were installed to treat storm water runoff from a planned parking lot. Models of the completed project showed a drop in flood elevations of up to 1.5 feet.
The Phase 4 projects, begun in 1999, focused on streambank and floodplain restoration in private backyards along Paradise Creek. Need for this project was high, as demonstrated by one landowner's loss of a 60-square-foot strip of her backyard to streambank erosion. Interested landowners provided buffer strips. The widths of their strips varied based on the erosion potential of their reach of Paradise Creek.
Restoring riparian areas on agricultural land along Paradise Creek was the goal for Phase 5. Before restoration, the stream channel had been straightened and acted as a drainage ditch for active agricultural land directly adjacent to the stream. As part of the restoration project, 3,600 feet of stream channel was relocated to follow its estimated historical path. Vulnerable banks were stabilized, and two new wetlands were excavated to act as a flood storage and groundwater recharge area and to provide habitat for wildlife. In spring 2000 PCEI and the landowner planted a 150-foot-wide buffer strip with a mix of native woody plant species.
Phase 6 involved the urbanized riparian floodplain and associated wetlands on public land along Paradise Creek within Moscow. Work took place along two reaches of the creek, resulting in the revegetation of more than 4,000 feet of stream by fall 2000.Phase 7 of the project is under way, focusing on the implementation of nonpoint source controls to achieve Total Maximum Daily Load allocations. The project includes construction of animal waste biofiltration swales and treatment wetlands, revegetation of riparian areas, streambank stabilization, and agricultural land restoration activities in association with other local agencies.
Streambank Stabilization in the Thomas Fork Watershed:
Photo Monitoring Sells Landowners on Bank Stabilization
Bear Lake Regional Commission
|Primary Sources of Pollution:|
|Primary NPS Pollutants:|
|decreased sedimentation—more than 200,000 cubic feet of sediment retained on streambank|
The Thomas Fork watershed covers 150,100 acres, with 39 percent in Bear Lake County, Idaho, and 61 percent in Lincoln County, Wyoming. The watershed is near where the states of Idaho, Wyoming, and Utah meet and is a subwatershed of the Bear River Basin. Because of the latitude and elevation of the watershed, the area typically has short, cool summers and long, cold winters. The watershed receives about 50 percent of its annual precipitation during the winter months. Most of this precipitation falls as snow and is stored in the snowpack at higher elevations for spring and summer runoff.
Thomas Fork is a tributary to the Bear River and is upstream from the point where the Bear River is diverted into Bear Lake. Bear Lake, which is half in Idaho and half in Utah, is a unique body of water with about 110 square miles of surface area. It contains five endemic fish species. In Idaho the lake has been designated a Special Resource Water.
The designated uses of Thomas Fork are cold water biota and salmonid spawning. The stream is listed among Idaho's 303(d) "water quality limited stream segments." The pollutants the state has identified as contributing to the watershed's water quality problems are sediment, nutrients, and habitat alteration. The primary nonpoint sources of pollutants to surface water are cropland and rangeland, animal feeding areas, riparian areas, stream channelization, and streambank modification.
The Bear Lake Regional Commission, a bistate organization, worked in partnership with the Bear Lake Soil and Water Conservation District, U.S. Department of Agriculture's Natural Resources Conservation Service, and local landowners to reduce the pollutant loading to Bear Lake that comes from the Bear River and Thomas Fork. The Soil Conservation District developed a watershed management plan, funded through an Idaho state agricultural water quality project.
The plan identified 12 critical areas needing treatment. Remediation activities for the first area selected focused on riparian and streambank problems and encompassed 100,842 linear feet. This area was further refined to a 20,000-foot segment of high streambank erosion in the Idaho portion of the Thomas Fork watershed.
The Bear Lake Regional Commission received 319 funding to install a series of best management practices, in partnership with area landowners. The types of practices employed included rock stream barbs, bank shaping and reseeding, tree revetment, rock riprap, channel armoring, fencing, and animal water gaps. The project was successful in treating 4,767 linear feet of streambank, installing 41 rock stream barbs, and installing 2,000 linear feet of permanent fencing.
The stabilization work resulted in a marked decrease in the amount of sediment entering Thomas Fork. Three types of monitoring techniques were used to measure the results of the stabilization work: photo points, water chemistry, and surveyed stream transects. The stream transects have revealed that for each foot of treated streambank as compared to an untreated site, 50 cubic feet of streambank material was retained on the banks over a 3-year period. This quantity of retained material per foot, when expanded to the entire treated area, amounts to more than 200,000 cubic feet of material retained.Photo monitoring helped demonstrate the rewards of bank stabilization work to other landowners. As a result, another 4,000 linear feet of streambank is scheduled for remediation in 2001.