irrigation water management

Download Irrigation Water Management

Post on 28-Jan-2016

97 views

Category:

Documents

0 download

Embed Size (px)

DESCRIPTION

Irrigation Water Management. An essential ingredient of irrigation system design operation. VERY important when applying animal waste. John Busch Irrigation Engineer USDA-NRCS 3990 Midway Lane Baker City, OR 97814 541-523-7121 ext 111 john.busch@or.usda.gov. Basic IWM concepts. - PowerPoint PPT Presentation

TRANSCRIPT

  • Irrigation Water ManagementAn essential ingredient of irrigation system design operation

    VERY important when applyinganimal waste

  • John BuschIrrigation EngineerUSDA-NRCS3990 Midway LaneBaker City, OR 97814

    541-523-7121 ext 111john.busch@or.usda.gov

  • Basic IWM concepts

    WHEN to irrigate ??

    HOW MUCH water to apply ??

    HOW MUCH is applied??

  • Irrigation Water ManagementImproper IWM can cause INUNDATION!How important ???

  • Irrigation Water ManagementImproper IWM can leave one HIGh & DRY!How important ???

  • Important Point..Errors in the timing and amount of irrigation applications can be PROBLEMATIC

    Potential problems can increase when applying animal waste through an irrigation system

  • NRCS IWM Job SheetAvailable on theOregon NRCS Engineering Web Site

  • IWM Plan Specifications

    An IWM Plan shall be developed to assist the irrigator or decision-maker in the proper management and application of irrigation water. Factors to be included in the IWM Plan include the following:Statement of objective(s) for the IWM PlanDescription of the irrigation system and its components including water supply, water conveyance and application systems, and any water measurement devices.Soils information including available water capacity, depth, and limiting conditions related to irrigation water management.Crop information including crops grown, irrigation water requirements, and physical characteristics including rooting depth.Description of irrigation scheduling and system management including methods for measuring and/or estimating crop water use and soil moisture levels.IWM record keeping requirements of appropriate detail for the IWM objectives. The detail of IWM may be specified as Detailed or By Irrigation Cycle with the associated level of record keeping as appropriate for the level of detail.IWM review requirements regarding the effectiveness of the IWM Plan and its implementation.

  • NRCS IWM Plan SpecificationsStatement of objective(s) for the IWM PlanDescription of the irrigation system and its componentsSoils information including available water capacity, depth, and limiting conditionsCrop information including crops grown, irrigation water requirements, and physical characteristics

  • NRCS IWM Plan SpecificationsDescription of irrigation scheduling and system managementIWM record keeping requirements of appropriate detailIWM review

  • IWM ObjectivesWork with cooperator to

    Identify needsSpecify objectives to meet needs

    Cooperator involvement is important !buy-in from the beginning

  • Irrigation SystemIrrigation system characteristics

  • Includes Big Guns

  • Irrigation SystemSystem type

    Operating characteristicsCoefficient of Uniformity (CU) data or distribution uniformity (DU) shall be used in selecting sprinkler spacing, nozzle size, and operating pressure

    For pivots: Min CU = 85%Fixed-Solid-set, Big Gun and Periodic Move Sprinkler: Min CU = 75 % for deep-rooted crops (4 ft +)Min CU = 85 % for shallow-rooted crops

  • Irrigation SystemWater Source(s)Available flow rate and total amountWater QualitySalts (Sodium)Chemicals (Boron)

  • Soils InformationIncludingSoil characteristicsPhysical data depth, limitations, AWCSoil chemistry EC, SAR

  • Soils Information

  • Water balance in root zoneApplied waterPrecipitationRunoffCapillary riseDeep perc (leaching)Root zone -- Water storage

  • Soil-water basicsSaturated ConditionField Capacity

  • Management Allowed DeficitMADAvailableWaterCapacityAWCFieldCapacityFC

  • Flocculation is important because water moves mostly in large pores between aggregates. Also, plant roots grow mainly between aggregates.

  • In all but the sandiest soils, dispersed clays plug soil pores and impede water infiltration and soil drainage.

  • Soils InformationDispersion and surface sealing from sodium

  • Crop InformationCrops grownIrrigation water requirementsRooting depthOther physical characteristics

  • Scheduling & System Management

    Check actual soil moisture levelsKnow the amount of irrigation water appliedKnow irrigation guidelines for crops grownTrack crop water use evapotranspiration

  • Soil Water ReservoirMeasure applied waterFarm deliveryField applicationEstimate CUMonthly estimate from regional weather dataDaily estimate from regional or on-site dataMeasure soil waterField probe + feelInstrumentation

  • Three elements for IWM

    Estimate or measure soil moistureMeasure irrigation water appliedEstimate crop consumptive use Need ALL 3 itemsESSENTIAL

  • Implementing IWMKnowledge of fields, crops, irrigation system

    Effective IWM requires judgment, observation, and local knowledgeUse ALL available information proceed cautiously, test, observe

    NO one knows the farm as well as the manager !

  • Scheduling & System Management

    Check actual soil moisture levelsKnow the amount of irrigation water appliedKnow irrigation guidelines for crops grownTrack crop water use evapotranspiration

  • IWM RecordsDate and duration of each irrigationWater applied in each irrigationDates and amounts of effective rainfallCrop water useDaily evapotranspirationWater use estimate between irrigationsSoil moisture status

  • IWM ReviewNotes on how well IWM goals were metDescription of crop response to IWM PlanObservations of soil erosion, etc. Notes on water/environmental quality issues (Relate to CNMP)Notes on irrigation system operations and maintenance

  • Thoughts, Questions, Comments??

    john.busch - ENDER....

  • NRCS IWM Plan SpecificationsDescription of irrigation scheduling and system managementIWM record keeping requirements of appropriate detailIWM review

  • Implementing IWMKnowledge of fields, crops, irrigation system

    Effective IWM requires judgment, observation, and local knowledgeUse ALL available information proceed cautiously, test, observe

    NO one knows the farm as well as the manager !

  • Water balance in root zoneApplied waterPrecipitationRunoffCapillary riseDeep perc (leaching)Root zone -- Water storage

  • Water balance in root zoneETApplied waterPrecipitationRunoff(erosion)Capillary riseDeep perc (leaching)Root zone -- Water storage(Check uniformity)

  • System managementRainfall -- measureET -- measure/estimateSoil water -- measure/estimateApplication -- measure/estimate Infiltration -- measure/estimateRunoff -- measure/estimate

  • Conclusion CANNOT depend onmeasuring/estimating only ONE parameter

  • Soil Water ReservoirMeasure applied waterFarm deliveryField applicationEstimate CUMonthly estimate from regional weather dataDaily estimate from regional or on-site dataMeasure soil waterField probe + feelInstrumentation

  • Irrigation SystemSystem type

    Operating characteristicsCoefficient of Uniformity (CU) data or distribution uniformity (DU) shall be used in selecting sprinkler spacing, nozzle size, and operating pressure

    For pivots: Min CU = 85%Fixed-Solid-set, Big Gun and Periodic Move Sprinkler: Min CU = 75 % for deep-rooted crops (4 ft +)Min CU = 85 % for shallow-rooted crops

  • Irrigation SystemSystem type

    Operating characteristicsCoefficient of Uniformity (CU) data or distribution uniformity (DU) shall be used in selecting sprinkler spacing, nozzle size, and operating pressure

    For pivots: Min CU = 85%Fixed-Solid-set, Big Gun and Periodic Move Sprinkler: Min CU = 75 % for deep-rooted crops (4 ft +)Min CU = 85 % for shallow-rooted crops

  • In A horizons, where organic matter levels are high and there is a lot of biological activity (earthworms, ants, termites, microbes, etc.) particles tend to be arranged in small, round aggregates or granules. This type of structure is common in the surface horizons of many forest and prairie soils

    In A horizons, where organic matter levels are high and there is a lot of biological activity (earthworms, ants, termites, microbes, etc.) particles tend to be arranged in small, round aggregates or granules. This type of structure is common in the surface horizons of many forest and prairie soils

Recommended

View more >