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Project Summary

Arroyo Colorado (NPS Prevention Project)

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1. Project Identification

Name Arroyo Colorado (NPS Prevention Project)
Region Gulf of Mexico
State TX
Location  
Date of this update  

2. Problem(s) addressed (check one or more)

Habitat Restoration/Protection  
Wetlands
River systems
Beaches/Dunes
Offshore areas
Mangroves
Assisting Species at Risk
Pollution Mitigation
Non-Point Source Pollution X
Other (describe)  

3. Project Description (100 words or less. Please include qualitative information, e.g. acres of habitat restored, miles of steam reopened to migration, and legislative authorization, e.g. WRDA, ISTEA, CWA/NEP, CZMA, etc.)

The lower Rio Grande Valley serves as an intensive agricultural region in Texas. Major crops, grown predominantly under irrigation from the Rio Grande, include citrus, grain, sugar cane, cotton, and vegetables. Area soils are naturally saline and this problem is complicated by a shallow, saline water table (five to seven feet). Drawdowns of the water table is conducted by sub-surface drainage systems installed on much of the irrigated land to mitigate toxic salt buildup. The water is then released into the Arroyo Colorado.

The Arroyo Colorado is one of the more complex watercourses in the state. From its headwaters to its mouth, it has been extensively modified by the activities of man, which is reflected in both its hydrology and water quality. Watershed activities are principally agricultural, although the Arroyo also drains the urban areas of Harlingen, McAllen, and other smaller communities who add their treated wastewater to the river. Its lowest reach is estuarine, and issues into the Laguna Madre, an extremely productive, high salinity embayment lying behind the barrier of Padre Island.

The water quality of the Arroyo Colorado has been variable historically. At low stages, it exhibits all the problems expected of a effluent dominated system in a hot, arid climate: high coliform counts, low dissolved oxygen and high algal concentrations. In the estuarine reach, these parameters are exacerbated by a circulation associated with salinity intrusion in a deepened channel. These same areas act as sinks for silt and mud, and frequently adsorb contaminants. During high stages, the water may be affected by urban and agricultural contaminants, especially pesticides. Past studies by the COE and the Texas Water Development Board have demonstrated the accumulation of pesticides in the deltaic sediments, especially malathion, chlordane and DDT degradation products.

The projects's examination of the remediation and prevention of pesticide and fertilizer NPS pollution into the Arroyo Colorado includes two demonstration areas. One demonstration area will evaluate Best Management Practices (BMPs) applicable to the study area and their effectiveness in abating NPS pollution from irrigated row crops and vegetable production. The BMPs will include integrated nutrient and pesticide management combined with filter strips. The second area will demonstrate BMPs on non-irrigated cropland. The project will also provide information and technical material to the public in an effort to reduce NPS pollution by increasing public awareness. These public education activities will occur through educational seminars and workshops, demonstration tours, dissemination of printed material, development of a documentary videotape, research papers and use of the mass media.

The project is being funded through a Section 319(h), Clean Water Act, grant to the Texas Natural Resource Conservation Commission from the EPA. Performance of the tasks will be a cooperative effort among the Texas State Soil and Water Conservation Board, the Texas Institute for Applied Environmental Research, the Texas Agricultural Extension Service, the U.S. Natural Resource Conservation Service, and the Southmost and Hidalgo Soil and Water Conservation Districts. Additionally, numerous coordinating and technical committees are being formed composed of federal, state and local government representatives and private agricultural interests.

4. Goals/Benefits (quantify where possible using measures of success list) Was a cost-benefit study conducted for this project? yes/no If yes, provide a summary of findings.

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5. Partners (include each participant's responsibilities - funding, permitting, etc.)

6. Funding/Contributions (organization and amount)

7. Legislative authorities used by each participant

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8. Value added by Coastal America Partnership including Government Performance and Results Act (GPRA) goals achieved through this collaboration (500 words or less)

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9. Project Status

Initiation date  
Completion date  
Current stage  

10. Contacts

11. Any additional information/comments

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This page was last updated on Saturday, 24-Jun-2000 11:48:47 EDT
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