The Seymour Aquifer is a shallow aquifer in Northwest Central Texas and the only major source of groundwater in Haskell, Jones, and Knox Counties. The aquifer underlies over 300,000 acres and furnishes drinking and domestic water for many rural families. In addition, over 3,000 wells furnish water for irrigation and livestock use. The State of Texas has identified elevated nitrate levels as a concern in Haskell, Knox, and Jones Counties. In over 75% of the wells tested, nitrate levels exceed the federal safe drinking water standard of 10 mg/L NO3-N. Nitrate levels have been documented in some wells as high as 35 mg/L NO3-N. To remove this threat, the Texas State Soil and Water Conservation Board (TSSWCB) is working cooperatively with the Haskell, Wichita Brazos, and California Creek Soil and Water Conservation Districts (SWCDs), Natural Resources Conservation Service (NRCS), Texas AgriLife Extension Service, Rolling Plains Groundwater Conservation District, Lower Seymour Groundwater Conservation District, and Texas Agricultural Experiment Station (TAES) to provide water quality education, technical assistance, and financial assistance to irrigators for BMP implementation in order to reduce nitrate concentrations in the Seymour Aquifer.
This program will serve as a catalyst to encourage the installation of Trickle (Drip) Irrigation Systems as a best management practice to improve water quality and increase water quantity in the Seymour Aquifer. Installation of Trickle (Drip) Irrigation Systems costs in excess of $1,000 per acre. The proposed project would provide cost-share to replace existing center pivot, sprinkler, or row-water irrigation systems with drip irrigation systems at a cost-share rate of 60 percent. The project area will include the irrigated portions of Haskell, Knox, and Jones counties.
The installation of drip irrigation systems will have a direct impact on the area groundwater by (1) reducing the potential for return flow of irrigation water into the aquifer (Return irrigation water flow has the potential to transport nutrients and pesticides into groundwater), and (2) increasing irrigation efficiency of row, center pivot, and center pivot systems therefore increasing water quantity.
Project Location: Seymour Aquifer – Haskell, Knox, Jones, Wilbarger, Hardeman and other surrounding counties
Project Participant(s): TSSWCB and Texas Water Resources Institute
Quality Assurance Project Plan: 04-09
Final Report: 04-09
Participating irrigators must develop a TSSWCB-certified WQMP in order to receive cost share. In this project, a technician will be employed by the Haskell SWCD, to assist landowners in the development, implementation, and/or maintenance of WQMPs. Assistance will be provided to the technician, when needed, by the TSSWCB Dublin Regional Office and NRCS. The technician will work in the adjacent Wichita Brazos and California Creek SWCDs through cooperative agreements between the participating SWCDs.
WQMPs insure farming operations are carried out in a manner consistent with state water quality standards. The TSSWCB will review all of the WQMPs to make certain they are consistent with the state water quality standards and certify those WQMPs that meet the necessary criteria. The objective of WQMP implementation is to achieve a level of pollution prevention or abatement determined to be consistent with State water quality standards.
A number of BMPs to reduce nitrate levels may be implemented through the development of WQMPs. However, only implementation of Trickle (Drip) Irrigation Systems will receive cost-share. Examples of other BMPs that may be included in WQMPs are:
• Irrigation management
• Nutrient management
• Integrated pest management (e.g., sprayer calibration, incorporation banding, follow label)
• Conservation tillage
Highest priority is given to the replacement of the least efficient irrigation systems. Feasibility of successful installation will also be considered. The Haskell, Wichita Brazos, and California Creek SWCDs, with assistance from the TSSWCB and NRCS, will prioritize the applications received and determine which landowners in their respective SWCDs will receive technical assistance for the development and implementation of WQMPs.
In summary, the following are actions that will be undertaken by this project to reduce the potential for nitrate infiltration into the Seymour Aquifer:
- Provide technical assistance to irrigators concerning the implementation of appropriate BMPs to aid in the reduction of nitrate infiltration.
- Provide three educational events describing methods for the reduction of nitrate infiltration.
- Provide financial assistance to irrigators for the implementation of BMPs in order to aid in the reduction of nitrate infiltration.
The TAES, in coordination with the Rolling Plains Groundwater Conservation District and Lower Seymour Groundwater Conservation District will evaluate the effectiveness of BMP implementation in reducing nitrate levels within the aquifer. It is hoped that the evaluation of the BMP and local interest resulting from implementation of this demonstration will encourage the establishment of an EQIP priority area for the Seymour to encourage further implementation of this BMP throughout the aquifer.
Project Goals/Objectives: The main goal of this project is to demonstrate management practices that mitigate nitrate movement in the soil within the Seymour Aquifer region. This project will generate and extend new knowledge to enhance Best Management Practices (BMPs) for nutrient and irrigation management within the Seymour Aquifer through establishment of a subsurface drip irrigation system at the Chillicothe Research Station. This project will also provide additional resources for quantifying and verifying the effectiveness of BMP implementation in reducing nitrate levels within the aquifer.
Project Costs: Federal ($909, 405); Non Federal Match ($516,346); Total Project ($1,425,750)