Jump to main content or area navigation.

Contact Us

Water: Nonpoint Source Success Stories

Oklahoma: Section 319 Success Stories, Vol. III

Begin Page Links Story 1  |  Story 2  |  Story 3  |  State Water Quality Site Exit EPA Disclaimer End Page Links Story Separation Bar Acid Mine Drainage Treatment Wetlands:
A Sustainable Solution for Abandoned Mine Problems



Contacts:
Robert W. Nairn, Ph.D.
The University of Oklahoma
405-325-3354
nairn@ou.edu

Oklahoma Conservation Commission
Water Quality Division
405-810-1002

Primary Sources of Pollution:

acid mine drainage

abandoned mines
Primary NPS Pollutants:

high concentrations of metals

acidity

sulfate
Project Activities:

installation of treatment wetlands systems
Results:

improved water quality (lower concentrations of metals, acidity removal)

increased populations of wildlife, fish, and macroinvertebrates

Acid mine drainage (AMD) is a major nonpoint source pollution concern in many former mining regions. AMD is formed by the oxidizing action of air and water on exposed sulfidic strata and is characterized by elevated concentrations of metals (especially iron and aluminum), acidity, and sulfate. In Oklahoma, AMD impacts from abandoned coal mining activities are most prevalent in the Gaines Creek watershed of Pittsburg and Latimer Counties.

ok1_1

Wetlands that rely on passive treatment technologies are a viable treatment for AMD.

Traditional mine drainage treatment technologies are not viable options at abandoned mines because of their laborious and cost-intensive nature. However, passive treatment technologies that rely on natural biogeochemical and microbiological processes to ameliorate AMD, such as treatment wetlands, often provide viable treatment alternatives if enough land area is available.

ok1_2

Dr. Keith Strevett, graduate student Denae Athay, and Dr. Robert Naim have sampled substrate for chemical and microbiological analysis.

In 1998, with support of a section 319 grant provided by EPA Region 6 and the Oklahoma Conservation Commission, the University of Oklahoma initiated a treatment wetlands demonstration project to improve the quality of contaminated water at the #40 Gowen site. Of the dozen or more identified discharges in the watershed, the Gowen site was identified as having the greatest impact on the stream due to AMD. Drainage from the site affects Pitt Creek, a tributary to Gaines Creek, which drains to Lake Eufaula. Both creeks are on the state's 303(d) list for metals and pH violations related to surface mining.

Treatment technology

At the Gowen site, a Successive Alkalinity-Producing System wetland treatment process was implemented. Treatment occurs in a four-cell system of alternating vertical flow wetlands (VF) and surface flow aerobic ponds (SF). AMD is sequentially treated by charging the waters with alkalinity in the first VF, then providing near-optimum conditions for precipitating metals in the first SF. Alkalinity consumed by metal hydrolysis in the first SF is recharged to the waters in the subsequent VF, thus allowing further precipitation of metals in the final SF.

ok1_3

Native wetland vegetation, including cattail, sedges, reshes, willow, and water primrose, lines the constructed cell.

The size of the AMD and the flow rate into the treatment cells were calculated based on land availability, metals loading, and acidity. Because treatment of the entire discharge with the land area available was not feasible, the system was sized to demonstrate effective treatment of only a portion of the flow. Based on contaminant loadings of about 18,000 and 7,000 grams per day of acidity and iron and anticipated removal rates of 30 to 40 grams per square meter per day of acidity from published data and column studies, the system was designed with a surface area of approximately 750 square meters.

All water flows through the treatment wetlands are gravity-driven. Only a portion of the entire discharge (about 20 liters per minute) flows through the demonstration project. Each VF includes three vertical sections. The top layer (standing water) provides water head necessary to drive water through the underlying substrate. The middle layer is designed to generate alkalinity by biotic and abiotic means. It consists of a 1-meter-thick mixture of spent mushroom substrate, limestone, and hydrated fly ash. The bottom layer is a gravel underdrain that acts as a highly permeable zone to transmit water leaving the system through a network of drainage pipes. The treatment cells were planted with native wetland vegetation.

Improvements in water quality

Chemical water quality and quantity and wildlife use have been monitored every 2 weeks for 2 years. Results indicate that the treatment wetlands have successfully improved water quality to within applicable regulatory guidelines for more than 2 years. Concentrations of iron, aluminum, and manganese have decreased significantly, and pH and alkalinity concentrations have increased significantly. The final effluent of the system has maintained a net alkaline condition (above 150 mg/L) with pH greater than 6. Concentrations of trace metals were either near the detection limit at all sampling locations (barium, cadmium, chromium, copper and lead) or retained completely by VF1 (nickel and zinc) to less than the detection limit.

Several species of amphibians, reptiles, birds, and mammals use the site. Biological assessments in the summer of 2000 indicated healthy populations of fish and macroinvertebrates in three of the four cells. Macroinvertebrate community structure indicates a trend from tolerant to less-tolerant species with flow through the wetland system.

Duplication of success

The Gowen treatment wetlands demonstration project—the first and only successful passive AMD treatment system in Oklahoma—represents a sustainable and cost-effective solution for the devastating impacts of AMD on the environment.

Perhaps the most exciting aspect of the project is the transferability of this technology to other mining-impacted watersheds. Already, the Gowen treatment wetland design is being applied to problems at the Tar Creek Superfund Site in Ottawa County, Oklahoma, and is being investigated for application in several other watersheds nationwide. The Tar Creek site is part of a former lead and zinc mining area and is ranked number one on the National Priorities List. Coupled vertical flow wetland and surface flow pond designs are applicable to these waters and represent the only treatment methodology that has been considered viable for improvement and restoration of the waters of Tar Creek.

The budget for the Gowen treatment wetlands demonstration project was $125,000. Partners in the effort included The University of Oklahoma School of Civil Engineering and Environmental Science, Oklahoma Conservation Commission's Water Quality Division, U.S. Environmental Protection Agency, Latimer County Conservation District, and landowners William Battles and Mindy Ledbetter. Local companies and volunteers provided in-kind assistance or donations.

 

Begin Page Links Story 1  |  Story 2  |  Story 3  |State Water Quality Site Exit EPA Disclaimer   End Page Links Story Separation Bar
Poteau River Comprehensive Watershed Management Program:
Local Involvement Ensures Program Sustainability



Contact:
Shanon Phillips
Oklahoma Conservation Commission
5225 North Shartel
Suite 102
Oklahoma City, OK 73118-6035
405-810-1002
Shanonp@ okcc.state.ok.us
Primary Sources of Pollution:

agriculture (poultry industry, pasture maintenance)
Primary NPS Pollutants:

nutrients

sediment
Project Activities:

education

agricultural BMPs

watershed model development
Results:

improved watershed model

sustained partnerships

The Upper Poteau River, including Wister Lake and its tributaries, is identified among Oklahoma's top priorities for nonpoint source control implementation in the state's section 319 Nonpoint Source Management Program. The river is cited as having impaired recreational and drinking water uses; nutrients and sediment are the major nonpoint source concerns. The land in the watershed is primarily agricultural and Forest Service land. Most of the agricultural land consists of pastureland and poultry houses.

Using section 319 grant monies from EPA Region 6, along with state match dollars, the Oklahoma Conservation Commission (OCC), Oklahoma State Cooperative Extension Service, Oklahoma State University Department of Biosystems and Agricultural Engineering, LeFlore County Conservation District, Natural Resources Conservation Service (NRCS), Blacklands Research Center, Poteau Valley Improvement Association, Lake Wister Advisory Association, residents of the Haw Creek Valley Watershed, Lake Wister/Poteau River Steering Committee, and U.S. Geological Survey worked in various capacities to calibrate and improve watershed models and implement best management practices (BMPs) and educational programs to restore and protect the water resources. The program incorporated all of the previous work in the Wister Lake/Poteau River watershed, such as the Clean Lakes Phase I Project and 7 years' worth of model development. One of the greatest successes of the program was the involvement of local residents and organizations in implementing the various program components and ensuring that the program will continue.

Lasting watershed-wide participation

Much of the project framework was created at a local level, making it easier to sustain several components of the project beyond the original FY 1994 section 319 funding. The steering committee was made up of representatives from the LeFlore County Conservation District, LeFlore County Cooperative Extension, NRCS, Farm Service Agency, Oklahoma Forestry Service, agricultural producers, local government and homeowners, and recreational interests. The committee met monthly throughout the project and continued to meet beyond the end of the project to discuss details of the program, plan future efforts, and make decisions regarding demonstration practices, their locations, and cost-share reimbursement percentages. Although practices were demonstrated in a subwatershed (the Haw Creek area of the Black Fork of the Poteau River), the remainder of the program was watershed-wide.

Of particular note are the activities the Conservation District has perpetuated beyond the life of the project. During the project, the Conservation District and District Conservationist secured 100 percent participation by the poultry producers in the demonstration area. They also established test plots to demonstrate the effectiveness of various BMPs at reducing nutrient and sediment runoff. They have continued to maintain these plots beyond the life of the project and have established additional plots from new sources of funding to sustain the effort. The District also established a successful education program, partnering with the Cooperative Extension Service and other groups, to inform citizens about the importance of water quality and methods of conservation. This education program has continued and expanded beyond the life of the project to include regular classes at the local college, a volunteer monitoring program, and continued newspaper articles and education programs at schools. These continued activities are geared toward expansion of the demonstrated practices outside the demonstration subwatershed.

Through their continued efforts, the Conservation District, NRCS, and other local partners have illustrated their commitment towards solving water quality problems in the watershed. In addition, the area is an Environmental Quality Incentives Program (EQIP) priority area and the District and NRCS have cooperated to target EQIP funds toward practices that benefit water quality. This commitment has led to future projects to demonstrate BMPs throughout the remainder of the Poteau River and Wister Lake watershed. An FY 2000 319(h) grant, along with state cost-share monies, is devoted toward demonstrating BMPs throughout the watershed and achieving the river's eventual support of beneficial uses and removal from the state's 303(d) list.

Providing a platform to improve the SWAT model

Yet another result of the project was a modification to the Soil and Water Assessment Tool, or SWAT. SWAT is a basin-scale hydrologic/water quality model developed to predict the effects of alternative river basin land use management decisions on water, sediment, and chemical yields. SWAT operates on a daily time step and is capable of simulating 100 or more years. The major components of the model are hydrology, weather, erosion, soil temperature, crop growth, nutrients, pesticides, subsurface flow, and agricultural management. SWAT offers distributed-parameter and continuous time simulation with flexible watershed configuration, automatic irrigation and fertilization, interbasin water transfer, and lake water quality simulation capabilities. It is widely used in the development of Total Maximum Daily Loads (TMDLs).

Until now, in-stream nutrient dynamics were not considered in the SWAT model. This meant that although the model did a good job predicting nutrient loading coming off land surfaces, it ignored the processes that affected the nutrients once they were in the stream. To simulate the in-stream dynamics, the kinetic routines from an in-stream water quality model, QUAL2E, were modified and incorporated into SWAT. The Blacklands Research Institute in Temple, Texas, integrated QUAL2E kinetics into the SWAT model. The resulting version of SWAT is now widely used in modeling basins and in TMDL development.

 

Begin Page Links Story 1  |  Story 2  |  Story 3  |  State Water Quality Site Exit EPA Disclaimer End Page Links Story Separation Bar
The Spring Creek Project:
Streambanks Stabilized Through Stream Restoration



Contact:
Jim Leach
Assistant Director
Oklahoma Conservation Commission
5225 North Shartel, Suite 102
Oklahoma City, OK 73118-6035
405-810-1039
jiml@okcc.state.ok.us
Primary Sources of Pollution:

logging

grazing
Primary NPS Pollutants:

sediment
Project Activities:

Rosgen classification

streambank stabilization
Results:

75 percent decrease in erosion

improved fish community

improved recreational benefits

stream meander migration slowed

Spring Creek, a tributary to Fort Gibson Lake, spans three northeast Oklahoma counties—Delaware, Mayes, and Cherokee. Over the years, intensive logging, clearing, and grazing in the watershed have resulted in bank erosion, contributing significantly to the gravel load in the stream. Movement of this gravel (bedload) has accelerated bank erosion, causing the stream to widen and become shallow. This channel instability has resulted in excessive streambank migration, loss of fish habitat, and decreased recreational benefit.

Fluvial geomorphology

Fluvial geomorphology is the study of the form or shape of stream channels as they flow over the land. Recent work by Dave Rosgen of Wildlands Hydrology has resulted in a stream classification scheme based on eight major variables. Rosgen's method is useful in that a stream's stable configuration can be determined and classified so that the disturbed stream can be restored to this form, using natural materials on-site. A stream restored using these techniques is stable and efficient at transporting bedload and flood flows. It is also aesthetically pleasing and provides better in-stream habitat for aquatic life.

The project

Bank restoration was implemented on two reaches of Spring Creek (Cherokee County) exhibiting highly accelerated bank erosion due to clearing for increased hay production. Rosgen's method was used to classify the current state of the segments and determine the channel configuration necessary to stabilize the bank. The reaches were reshaped accordingly, and rock vanes, cross vanes, tree root-wads, logs, and vegetation were strategically inserted to affect stream flow and preserve or supplement habitat. Habitat and fish surveys were conducted before and after implementation to assess the project's effects in these areas.

Significant improvement

In general, the project sites showed significant, positive changes from the preimplementation survey. Physically, water depth through the reaches almost doubled and total area of eroding bank decreased by about 75 percent. A visit to the project site in August 2001 showed the stream channel modifications still holding effectively. Rock vanes had successfully diverted flow to the center of the channel, deepening pools and controlling erosion on the outside of the steam bends. Stream channel stabilization was apparent from the abundance of established tree saplings and other marginal vegetation.

Some of the most notable effects of the project were exhibited in the fish community. Both project sites exhibited more species and markedly higher total numbers of fish in the postimplementation survey (1.5 and 3.5 times the preimplementation numbers for downstream and upstream sites, respectively). The total number of pool species (sunfish, chub, suckers) increased by at least 2.4 times the previous abundance in both project reaches, reflecting the deepening and enlargement of pools and changes in the overall stream channel shape. The size composition of this group indicated multiple year classes, and young of year were found for all three species. Thus, it appears that the slower flow regimes and increased habitat resulting from stabilization efforts combined to affect overall reproduction of fish in this area of Spring Creek.

Certain beneficial uses also were restored or preserved in this area of the creek. Bank instability and subsequent gravel input had shallowed many areas, limiting fishing and swimming activities previously enjoyed. The upstream site has stabilized into a long pool deep enough for swimming and fishing. Good numbers of catchable sportfish have been noted in and around the rock vanes at the site.

An additional benefit has been the near cessation of channel movement through the project reaches. In particular, channel migration that previously threatened an important road through the property has been arrested through bank stabilization efforts. Little to no movement was discernible during the August visit.

 

Story 1  |  Story 2  |  Story 3  |  State Water Quality Site Exit EPA Disclaimer


Jump to main content.