Irrigation System, Surface

Irrigation System, Surface POLLUTANTS ADDRESSED: Nutrients and Organics, Salinity, Sediments

DESCRIPTION: This is a system that efficiently distributes irrigation water directly to the point of application. Surface irrigation requires well designed furrows, borders, contour levees, contour ditches, or a subsurface apparatus.

ADDITIONAL BENEFITS: None

POTENTIAL TREATMENT AREAS: Agricultural Lands

LOAD REDUCTION MECHANISM: Nutrients/Organics Management- A properly designed surface irrigation system will reduce erosion and water loss, thereby reducing the transport of agricultural fertilizers and other organics into surface waters.

Salinity Reduction- Reduced erosion and water loss will reduce the transport of salts into surface waters.

Sediment Reduction – Similarly, reduction in erosion will reduce the transport of sediments into adjacent surface waters.

LAND USE CLASSIFICATION: Agricultural lands

Arid Southwest BMP

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ALTERNATIVE MANAGEMENT MEASURES: Irrigation Land Leveling Irrigation System, Tailwater Irrigation Water Management

PERMITTING REQUIREMENTS: None

Irrigation System, Surface POLLUTANTS ADDRESSED: Nutrients and Organics, Salinity, Sediments

Level 400: MODERATE ENGINEERING LOAD REDUCTION POTENTIAL: LOW

MEDIUM

8. The volume of downstream flow that could have environmental, social, or economic impacts.

HIGH 9. Field water table in providing a suitable rooting depth for anticipated land uses.

ESTIMATED TIME FOR LOAD REDUCTION: IMMEDIATE

MONTHS2 YEARS EXPECTED MAINTENANCE: LOW

MEDIUM

> 2 YEARS

10. Erosion and the movement of sediment and soluble and sediment-attached substances carried by runoff.

HIGH

11. Temperature of downstream waters.

ESTIMATED COST: LOW

MEDIUM

12. Aquatic and wildlife communities, wetlands or water related wildlife habitats.

HIGH 13. The visual quality of water resources.

PLANNING AND IMPLEMENTATION: When planning a surface irrigation system, the following items should be considered, where applicable:

14. Possible impacts on cultural resources.

Riparian Planting Zone: Upland Zone and Flood flows

1. Effects of nutrients and pesticides and other dissolved substances on surface and ground water quality.

ADDITIONAL SOURCES OF INFORMATION:

2. Effects of water level control on the salinity of soils, soil water or downstream water quality.

Conservation Practice Standard, Irrigation System, Surface and Subsurface, prepared by the Natural Resources Conservation Service. http://www.ag.ndsu.edu/pubs/ageng/irrigate/ae91.pdf

3. Effects of water levels on such soil nutrient processes as plant nitrogen use or denitrification.

4. Impact of salt leaching on system management and capacity requirements.

Implementation considerations include: 5. The water budget, especially volumes and rates of runoff, infiltration, evaporation, transpiration, deep percolation, and ground water recharge.

6. Plant growth and transpiration because of changes in the volume of soil water.

7. Downstream flows or aquifers that impact other water uses or users.

Arid Southwest BMP

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