Irrigation System, Drip

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

DESCRIPTION: A drip system brings water to the root zone of the plants by means of emitters, orifices, or porous tubing. The purpose of this technique is to efficiently and uniformly apply irrigation water and to maintain soil moisture for optimum plant growth.

POTENTIAL TREATMENT AREAS: Agricultural lands

LOAD REDUCTION MECHANISM: Nutrients/Organics Management- A drip irrigation system brings water directly to the plants roots, eliminating surface runoff.

Salinity Reduction- A drip irrigation system does not allow salt to accumulate in soils because water surface runoff is eliminated.

Sediment Reduction – Reduction in surface runoff reduces erosion and the production of suspended sediments.

PERMITTING REQUIREMENTS: none

ALTERNATIVE MANAGEMENT MEASURES: Irrigation Pipeline Irrigation Water Management

LAND USE CLASSIFICATION: Agricultural lands ADDITIONAL BENEFITS: Maintains soil moisture for optimum plant growth.

Arid Southwest BMP

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

Level 400: MODERATE ENGINEERING LOAD REDUCTION POTENTIAL: LOW

MEDIUM

4. Microirrigation will effect a change in plant growth and transpiration because of changes in the volume of soil water.

HIGH

5. There may be a potential for development of saline seeps or other salinity problems resulting from increased infiltration near restrictive layers.

ESTIMATED TIME FOR LOAD REDUCTION: IMMEDIATE

MONTHS2 YEARS

> 2 YEARS

6. Field shape and slope frequently dictate the most economical lateral direction. Whenever possible, laterals should be laid downslope for slopes of less than 5% if lateral size reduction can be attained. For steeper terrain, lateral lines should be laid along the field contour and pressure compensating emitters should be specified or pressure control devices used along downslope laterals.

EXPECTED MAINTENANCE: LOW

MEDIUM

HIGH

ESTIMATED COST: LOW

MEDIUM

HIGH

PLANNING AND IMPLEMENTATION:

Riparian Planting Zone: Upland Zone and Flood flows.

1. Water quality is usually the most important consideration when determining whether a microirrigation system is feasible. Well and surface water often contains high concentrations of undesirable minerals (chemicals). Surface water can contain organic debris, algae, moss, bacteria, soil particles, etc. Well water can also contain sand.

SOURCES FOR ADDITIONAL INFORMATION: TMDLs for Total Dissolved Solids in the Duchesne River Watershed, prepared for the US Environmental Protection Agency by the Utah Department of Environmental Quality, Division of Water Quality, and the NRCS New Jersey Irrigation Guide, prepared for the US Department of Agriculture, Natural Resources Conservation Service. http://www.waterquality.utah.gov/TMDL/Duchesne _River_Watershed_TMDL.pdf

2. Microirrigation can influence runoff and deep percolation by raising the soil moisture level and decreasing available soil water storage capacity, increasing the probability of runoff or percolation below the root zone from storm events. The movement of sediment, soluble chemicals, and sediment-attached substances carried by runoff may affect surface water quality. The movement of dissolved substances below the root zone may affect groundwater quality.

3. On systems where chemicals are injected, care shall be taken so the injected nutrients do not react with other chemicals in the irrigation water to cause precipitation and plugging.

Arid Southwest BMP

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