Water: Nonpoint Source Success Stories
Tangipahoa River Projects -
Using an Ecosystem-Based Approach
The Tangipahoa River flows for 79 miles southeast across the Mississippi and Louisiana state lines to Lake Pontchartrain. The northern segment of the river is an upland stream that flows through rolling hills above a sand and gravel substrate; the southern segment is a lowland stream that widens and flows through a cypress/tupelo swamp before entering Lake Pontchartrain. Most of the watershed is rural, consisting of pine forests, pastures, truck farms, and upland dairies, with swamps and marshes in the lower portion. Dairy farming is a predominant land use in the watershed; Tangipahoa Parish alone has 273 dairies. Other agricultural land uses truck farms, beef, poultry, fish, and swine operations follow dairy farming in that order. Industries in the area are primarily agricultural, such as milk, fish, and meat processing.
A potential health hazard
Public concern for the safety of the Tangipahoa River for swimming and tubing began in October 1987, when a graduate student concluded that the river was not meeting water quality standards for primary contact recreation; and, later, that high levels of fecal coliform in heavily used beach areas could pose a health hazard.
A review of historical fecal coliform data from the Tangipahoa River and preliminary results of a sampling program begun in October 1987 confirmed her judgment. In 1988, the Louisiana Department of Health and Hospitals, in conjunction with the Louisiana Department of Environmental Quality, issued an advisory to residents along the Tangipahoa River of a potential health hazard from primary and secondary contact recreation in the river. The entire river was not in violation of the bacteria standard; however, the standard is exceeded periodically at all sampling stations. Thus, the advisory covered the entire length of the Tangipahoa River.
Bacterial contamination in the Tangipahoa River includes both point and nonpoint sources. Fecal coliform bacteria reside in the intestinal tracts of warm-blooded mammals, both humans and animals, and are released to the environment in wastewater and from nonpoint sources. During an initial investigation, 11 wastewater treatment facilities were inspected, and enforcement action was recommended for nine of these facilities. Nonpoint sources of pollution were also identified, including runoff from unanswered or poorly answered communities and recreational campgrounds, and animal wastes from dairy farms and other animal holding operations.
Communities with no sewage systems or poor sewerage worked with the Tangipahoa Parish sanitarian and the Household Sewage Committee to reduce the level of untreated sewage entering the river. In recent years, more than 7,882 new home sewerage systems have been installed in the parish. The Louisiana Department of Environmental Quay has also contracted with the Louisiana Cooperative Extension Service to implement an education program focusing on the maintenance of existing septic systems and installation of traditional individual sewage systems.
The U.S. Environmental Protection Agency also awarded funding to Tangipahoa Parish for the construction of a sewage treatment plant to alleviate problems faced by the parish resulting from a shortage of available locations for the proper disposal of septic tank sludge. The sewage treatment plant was completed in 1995 and began full operation in the spring of 1996. The section 319 grant supported lagoon clean-out programs and education programs for the proper siting, selection, and maintenance of home sewage systems.
Controlling dairy runoff
To control runoff from dairies, the Department of Environmental Quay requested that all farmers in the parish apply for NPDES permits or install no-discharge animal waste management systems (lagoons). Over 125 farmers agreed to install treatment systems. Design specifications were developed by the Natural Resources Conservation Service (NRCS) and the Louisiana Cooperative Extension Service. These agencies also provided technical assistance for the construction of lagoons or other waste treatment structures.
Farmers are eligible for federal cost-share assistance through the Farm Service Agency, NRCS, and the Lake Pontchartrain Basin Foundation and for state cost-share assistance through the Louisiana Departments of Environmental Quay and Agriculture and Forestry. During 1996, 120 dairies were inspected to determine their status on installing no- discharge animal waste management systems and applying for wastewater discharge permits for their dairy operations. These inspections resulted in 60 notices of violation and one compliance order. The remaining dairy operations have agreed to participate in the program.
Based on the most recent data from the Tangipahoa River, average and median levels of fecal coliform continue to decrease, meeting state water quay standards for primary and secondary contact recreation during portions of the year. The Louisiana Department of Environmental Quay will continue to monitor the river closely to determine when the health advisory can be lifted.
Other projects in the watershed have emerged from the cooperation between federal and state agencies working to restore the Tangipahoa River. These projects include, for example, a Forestry Nonpoint Source Task Force and a Hydromodification Demonstration Project modeling alternative methods for control of vegetation along streambanks, waterways, and canals.
Both projects emphasize the importance of leaving trees and other vegetation along the edge of the bayou or drainage canal, since these riparian areas provide filtration for nonpoint sources of pollution and nutrient assimilation. As more native habitats are encouraged and maintained along the streambank, water quay should improve and maintenance costs decline.
Volunteer monitoring programs have also been implemented along the Tangipahoa River, and their results indicate that conditions in the river continue to improve. In sum, these cooperative efforts lead to a better understanding of water quay problems in the Tangipahoa River; they are also helping to reduce pollution to levels that will soon, residents hope, permit the lifting of the health advisory.
CONTACT: Jan Boydstun
Louisiana Department of Environmental Protection
Louisiana's Bayou Queue de Tortue Watershed -
Incorporating BMP Demonstrations in Pollution Prevention Plans
Bayou Queue de Tortue -- its French name means "tail of the turtle" -- is located in the Mermentau River Basin in southwest Louisiana. The area is often referred to as the "rice capital of the world." One of the first watersheds in the state targeted for nonpoint source implementation activities, Bayou Queue de Tortue exemplifies most of the problems in the Mermentau River Basin. Since the Mermentau has more bayous not meeting their designated uses than any other Louisiana basin, demonstration projects in Bayou Queue de Tortue can have a significant area-wide impact on water quay.
The Bayou Queue de Tortue Task Force began in 1989 as a joint cooperative effort to coordinate section 319 programs with USDA programs such as the President's Water Quay Initiative. The task force included staff from the Louisiana Department of Environmental Quay, the Louisiana State University Rice Research Station, the USDA Natural Resource Conservation Service (NRCS), the Louisiana Cooperative Extension Service, and the Farm Service Agency (FSA).
Most bayous in the Mermentau River Basin are impacted by sediment, nutrients, organic enrichment, and low dissolved oxygen levels, all of which affect fish habitats and fisheries. Agriculture and hydromodification are the two primary activities that contribute to water quay impairments in the basin.
Rice growing in the watershed
In the Bayou Queue de Tortue Watershed, 92 percent of the land is used for agriculture, primarily rice and soybeans. Farmers here and throughout the basin use mudding-in and water-seeded rice as cultural practices to control the weed, red rice. As a result, water used to irrigate rice fields before and during the planting season is laden with solids, nutrients, and metals. Its discharge affects the streams and bayous, especially during the spring planting season when most traditional mudding-in practices are used. Working rice fields in water results in suspension of soil particles in irrigation water. If irrigation water is discharged before soil particles settle out, topsoil is lost and sediment is deposited in the receiving water. Because of the prolonged time period for settling of soil particles, removal of even 50 percent of the sediment is a challenging goal. As rice field discharges are released from fields through drainage canals to the bayous, bottom sediments are resuspended, creating a sediment oxygen demand (SOD) in the bayou. Dissolved oxygen levels in the bayous barely average 2.0 to 3.0 milligrams per er (mg/L), and when rice field discharges are released, these levels are significantly reduced, ranging from 0.2 to 0 mg/L.
Beginning with the 1990 planting season, farmers participated in a multiyear demonstration project to evaluate the effectiveness of rice management practices in improving water quay in the Mermentau River Basin. The Farm Service Agency provided cost-share assistance to rice growers in the project area (the Bayou Queue de Tortue Watershed), while NRCS and local soil and water conservation district staff provided technical assistance to the participating farmers.
The project developed and recommended four management practices for rice:
- no-till rice planting -- water planting into previous crop residue with no mechanical soil disturbance;
- mudding-in with a 15-day settling period -- flood water is retained in a closed levee system constructed prior to soil disturbance;
- dry cultivation with clear water planting -- clear water planting into a prepared seed bed; and
- mudding-in with a vegetative filter strip -- retention of flood water in a closed levee system constructed prior to soil disturbance; flood water is drained into an adjacent area where native vegetation is maintained.
The clear water and no-till rice plantings were equally effective in reducing sediment concentrations in the initial discharges. Mudding-in with a vegetative filter strip also significantly reduced sediments from rice fields as compared with the traditional mudding-in practice. Results from the project indicate that all four management practices can improve the quay of rice field discharges, though results differ, depending at least in part on historic conditions in the treatment streams.
Numeric evaluation -- water monitoring Department of Environmental Quay analyses of Bayou Queue de Tortue and other bayous in the Mermentau River Basin show improvements in dissolved oxygen concentrations. Dissolved oxygen levels showed declining tendencies from 1982 to 1989, before the demonstration project was implemented. The reverse is true from 1990 to 1995, when average dissolved oxygen concentrations increased from 2.434 mg/L in the preproject time period (1982-1989) to 3.335 mg/L during the project implementation time period (1990-1995).
Other data also illustrate the success of this project. For example, from 1991 through 1994, FSA cost-share funding helped support the four recommended rice best management practices (BMPs) on over 80,000 acres. Since then, interest in water quay improvement and BMPs has continued without FSA cost-share assistance. Rice growers voluntarily used the recommended BMPs on over 3,200 acres in 1996 motivated by concern for water quay and topsoil losses from their farms.
According to a report from the Louisiana State University (LSU) Rice Research Station, conservation tillage practices were used to plant an estimated 99,600 acres statewide during the 1996 planting season. This acreage represents approximately 20 percent of the total rice acreage in Louisiana. Of the acres planted with conservation tillage practices, 13,000 acres were within the project area, and 10,000 acres were in adjacent areas in Vermilion Parish.
In 1996, the Farm Service Agency submitted Bayou de Queue Tortue as one of three priority watersheds for additional cost-share funding through the Water Quay Incentive Program, a move that will result in the use of additional BMPs on rice fields.
Narrative evaluation -- ongoing activities
The Bayou Queue de Tortue Task Force continues to support activities to improve the bayou's water quay. First, to address the sediment problem more directly, the Louisiana Department of Environmental Quay and the Louisiana Cooperative Extension Service have developed a suspended sediment test kit to enable rice producers to reduce soil loss by determining the amount of sediment suspended in irrigation water. The test kit contains a chart that indicates (in parts per million) the amount of suspended sediment contained in the sample and also estimates (in inches) the amount of topsoil that would be lost in 100 years if the water were released when tested instead of after the soil particles had settled out.
During the 1996 planting season, the LSU Agricultural Center disseminated 750 test kits free of charge to rice producers in the Mermentau River Basin. During the 1997 planting season, a total of 1,500 kits were distributed. Second, the Louisiana Department of Environmental Quay, the state legislature, USDA, and various agricultural commodity producer groups, such as parish, regional, and state rice growers' associations, provide ideas and funding for many educational programs to help reduce nonpoint source pollution in the Mermentau River Basin and to encourage other farmers to adopt the BMPs used in the Bayou Queue de Tortue Watershed. These agencies are also helping farmers build their pollution planning skills. Because 82 percent of the rice growers and 75 percent of Louisiana's total rice acreage are located in the Mermentau River Basin, Cooperative Extension will develop a model pollution prevention plan (PPP) for introduction in this area. (Since 1990, Louisiana has required that all agricultural producers must develop and follow such plans). To ensure that the rice field PPP will cover most if not all potential sources of nonpoint pollution encountered by rice producers, initial field tests in the Mermentau River Basin are planned for 1997. Once the model has been developed, the public will be made aware that additional help is available to those needing to develop farm-specific PPPs; and the tenets and practices in the model plan will be adapted as son plans for use by 4-H agents, volunteer leaders, and teachers in grades K through 12. This aspect of the project is still in the development process, and extension agents have submitted a proposal to expand the effort to the entire Mermentau River Basin. The Department of Environmental Quay anticipates initiation of this project during 1997.
CONTACT: Jan Boydstun
Louisiana Department of Environmental Protection