![Page 1: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/1.jpg)
Vineyard Irrigation Proficiency Series – Part 3
Chemigation for Vineyard Drip Irrigation Systems
January 29, 2021
![Page 2: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/2.jpg)
Agenda
• Principles of Chemigation• Laws and Regulations• Types of Injectors• Drip Clogging and Water Quality Concerns• Fertilizers, Chlorine and Acid injection• Calibration of Equipment
• Demonstration of Injector Calibration (video)
![Page 3: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/3.jpg)
Chemigation
The process of injecting an approved chemical into irrigation water and applying it through
the irrigation system to a crop or field.
![Page 4: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/4.jpg)
Chemigation
General term that includes:• Fertigation• Insectigation• Fungigation•Nematigation
![Page 5: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/5.jpg)
Advantages of Chemigation
• Uniformity of application• Precise application• Economics• Timeliness• Reduced soil compaction and crop damage• Operator safety
![Page 6: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/6.jpg)
Disadvantages of Chemigation
• High management• Additional equipment• Must calculate injection rates and volumes• Injection equipment must be calibrated
![Page 7: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/7.jpg)
Chemigation – Laws and RegulationsGeneral Classes• Controlled Substances
(pesticides and herbicides)
• Fertilizers and Nutrients
• Drip Maintenance/Clogging Control Chemicals (chlorine, acid)
![Page 8: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/8.jpg)
Controlled Substances
Typically Pesticides and Herbicides
• Highly regulated by the EPA and States
• Regulations cover labeling, mixing/injection, and equipment
• Regulations designed to protect the environment, human health and water supplies
![Page 9: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/9.jpg)
Other Chemicals….
Fertilizers and NutrientsDrip Maintenance/Clogging Control Chemicals
• Regulated by the Texas Commission on Environmental Quality
• Requires backflow prevention devices for public water supply and groundwater protection
![Page 10: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/10.jpg)
The US EPA’s Label Improvement Program (LIP)
• Established in the 1980’s (fully implemented in 1988)
• States were required to implement regulations at least as stringent as proposed by the EPA
![Page 11: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/11.jpg)
The US EPA’s Label Improvement Program (LIP)
• Labels must state whether product is approved to be applied through the irrigation system
• Application instructions are provided
• Requires use of specific safety equipment and devices designed to prevent accidental spills
![Page 12: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/12.jpg)
Reading Chemical Labels
![Page 13: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/13.jpg)
Example #1
![Page 14: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/14.jpg)
![Page 15: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/15.jpg)
![Page 16: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/16.jpg)
![Page 17: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/17.jpg)
Summary of Chemigation Equipment Requirements
![Page 18: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/18.jpg)
![Page 19: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/19.jpg)
1. Irrigation Pipeline
• Check valve between well and injection points*• Vacuum relief valve between check valve and well• Low pressure cut off• Low pressure drain*
*Alternative safety equipment may be substituted approved by EPA, March 1989.
![Page 20: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/20.jpg)
2. Injection Hose
• Anti‐back flow injection valve – 10 psi• Normally closed solenoid valve between injection pump and chemical tank*
• A metering type injection pump*
*Alternative safety equipment may be substituted approved by EPA, March 1989.
![Page 21: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/21.jpg)
3. Power Interlock
• Interlock injection pump and water pump power• Interlock normally closed solenoid valve and injection pump power
![Page 22: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/22.jpg)
Other Chemicals
• Fertilizers and Nutrients• Drip Maintenance/Clogging Control Chemicals
• TCEQ regulations are designed to protect water supply
• Basic requirement is a check valve (backflow prevention valve) when connected to a water well or public water supply
![Page 23: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/23.jpg)
Requirements for water wells…
All irrigation distribution systems … into which any type of chemical … or other foreign substances will be injected into the water pumped from wells shall be equipped with an in‐line, automatic quick‐closing check valve capable of preventing pollution of the ground water.
![Page 24: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/24.jpg)
Other Required Devices
Installed between the pump discharge and the check valve• Vacuum‐relief device• Automatic low pressure drain• Inspection port
![Page 25: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/25.jpg)
Chemigation Injectors and Pumps
The most common types:• Mechanical
• Piston (positive displacement) pumps• Diaphragm pumps
• Venturi meters• Other
• Water Driven
![Page 26: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/26.jpg)
Piston/Positive Displacement Pumps• Uses a “piston” to inject chemical into the irrigation water
• Rate is determined by the• length of the stroke• number of strokes per minutes
• Chemicals come into contact with piston, so materials should be matched
![Page 27: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/27.jpg)
Piston/Positive Displacement PumpsInjection rate remains constant and does not change if the irrigation pipeline pressure varies
• Injection rates cannot be adjusted while operating • Commonly used to inject fertilizer (large rate injection)
![Page 28: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/28.jpg)
Piston/Positive Displacement Pumps
![Page 29: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/29.jpg)
Diaphragm Pumps
• A membrane separates chemical from the drive mechanism (piston)
• Easy to adjust flow rate while operating • Commonly used for low‐rate injection (pesticides, etc.) or continuous injections (chlorine or acid to lower pH)
• Easy to calibrate and maintain
![Page 30: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/30.jpg)
Diaphragm Pump
![Page 31: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/31.jpg)
Diaphragm Pump Operation
![Page 32: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/32.jpg)
Venturi Meters
• Simple device with no moving parts• The meter uses a reduced diameter throat tube (or a tube with a needle valve or orifice plate)
• Velocity changes in tube create vacuum to pull chemical into stream
![Page 33: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/33.jpg)
Venturi Meters
![Page 34: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/34.jpg)
Venturi Meters
•Most low‐end venturi injectors are not adjustable and have a constant proportion injection rate such as 1:50 (one gallon injected for every 50 gallons flowing through meter)
• Suction‐Injection rates are calibrated by adjusting the inlet and outlet pressure by controlling the flow through the venturi
![Page 35: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/35.jpg)
Venturi Meter Selection/Calibration
![Page 36: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/36.jpg)
• Also called Proportional Injectors• A water driven “engine” moves a piston within a cylinder at a proportional rate to the flow
• Available in fixed ratio and adjustable models• Commonly used only for chlorine or fertilizer
Water Driven Injectors
![Page 37: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/37.jpg)
Water Driven Injectors
![Page 38: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/38.jpg)
Injecting Fertilizers
![Page 39: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/39.jpg)
Fertilizers
• Frequently injected into drip irrigation systems• dry and liquid formulations are available• liquid formulations are more expensive but are very convenient
• can be injected directly (without mixing with water) with a variable rate injector.
![Page 40: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/40.jpg)
Fertilizers
• Fertilizers containing phosphorus and sulfur may react with calcium and/or magnesium in irrigation water
• forming precipitates that could clog emitters
• Micronutrients can also cause precipitates• Consult with supplier before use or test prior to injection
![Page 41: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/41.jpg)
Fertilizers
• Solubility of dry formulas varies depending on type and water quality
• Incomplete dissolving may result in clogging of emitters and lines
• Solubility in Pure waterammonium nitrate 9.8 lb/galcalcium nitrate 8.5 lb/galpotassium chloride 2.3 lb/galpotassium nitrate 1.1 lb/gal
![Page 42: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/42.jpg)
Fertilizers ‐ Summary
• Test solubility first• Beware of formulas containing phosphorus/sulfur in waters with calcium/magnesium
• Use soluble chelated forms of micronutirents• Liquid fertilizers are more expensive, but easier to deal with
![Page 43: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/43.jpg)
Fertilizers
• Following the 1‐2‐1 method when injecting fertilizers
• first 25% of the irrigation set, inject no fertilizer –allowing the pipelines to fill
• inject during the middle half of the irrigation • no injection during the final quarter of the irrigation to allow the pipelines to be flushed and to move the fertilizer in the soil away from the emitter
![Page 44: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/44.jpg)
Useful Conversion Factors
1 ppm = 1 mg/l1 ppm = 1 mg/kg1 % = 10,000 ppm1 % = 1.33 oz (by weight) per gal of water0.1% = 1000 ppm
![Page 45: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/45.jpg)
Clogging Control
![Page 46: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/46.jpg)
Clogging Control
• Biological ‐ Chlorine• Aglae• Bacteria
• Minerals ‐ Acids• Iron• Calcium/Lime• Salts• Etc.
![Page 47: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/47.jpg)
Chlorine
• Inject chlorine to control biological clogging of lines and emitters
• Water high in iron or sulfur may foster bacterial activity, particularly in combination with fine suspended solids (< 100 microns)
![Page 48: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/48.jpg)
Chlorine
• Injected to control biological clogging of lines and emitters
• Household bleach is often used in small systems (5.25% Chlorine)
• Use formulas with higher concentrations if iron bacteria and/or organic matter are problems
![Page 49: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/49.jpg)
• Container label will specify concentration
Chlorine
![Page 50: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/50.jpg)
Chlorine
• Chlorine concentration at the end of the drip line should be:
‐ 1 to 2 ppm for occasional treatment‐ 0.5 to 1 ppm for continuous treatment
• Begin with injection of low concentrations (5 ppmto 10 ppm) for one hour
![Page 51: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/51.jpg)
Acid Injection
• Acid is injected to control mineral clogging of emitters
• Water likely to cause problems:• High water pH (>7.5) • “moderate” to “hard water”
• >60 ppm Ca• >500 mg/l TDS (total dissolved solids)
![Page 52: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/52.jpg)
Acid Injection
• Inject acid to lower pH to about 6.5 for mild clogging problems
• For more severe clogging, lower the pH to 4• Expose emitters to this concentration for ½ to 1 hour
![Page 53: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/53.jpg)
Acid Injection
• 98% sulfuric acid is commonly used in drip irrigation
• Other common acids:• Nitric Acid• Phosphoric Acid• Hydrochloric Acid (Swimming Pool Acid)
• Citric acid or vinegar can be used in organic farming
![Page 54: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/54.jpg)
Acid Injection
• Laboratories can do a titration analysis which will determine the amount of acid needed to lower the water to a certain pH
• Texas A&M Soil, Water and Forage Testing Lab
• The injection rate (gal per hour) of acid is calculated by
IR= injection rate, gal per hrA = gal of acid needed to lower pH (per ac‐ft of water)Q = Flow rate of irrigation system (gpm)
![Page 55: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/55.jpg)
Water Quality
• Highly Recommended water sources be tested prior to any chemigation to avoid negative reactions
• TAMU Soil Testing Lab has specific analysis for water used in drip irrigation
• More info at http://SoilTesting.tamu.edu
![Page 56: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/56.jpg)
Water Quality Testinghttp://soiltesting.tamu.edu
![Page 57: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/57.jpg)
Calibration of Equipment
• Small differences in injection rates make large differences in total amount of chemical applied
• Results in insufficient or excessive application
• Calibration involves injecting water and checking the actual volume of water injected
![Page 58: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/58.jpg)
Calibration of Equipment
Useful conversionsvolume1 gal = 3,785 ml1 oz = 29.57 ml
flow1 ml/min = 0.016 gal/hr63.09 ml/min = 1 gal/hr1 oz/min = 0.469 gal/hr
![Page 59: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/59.jpg)
Calibration of Equipment
For fixed ratio injectors, check the injection ratio
100:1 means that one gal of solution will be injected for each 100 gal of water flowing through the unit
![Page 60: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/60.jpg)
Calibration of Equipment
For adjustable injectors:• Calculate the desired injection rate (gal/hr, ml/min) • Then calibrate/adjust injector accordingly
![Page 61: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/61.jpg)
Calculations ‐ Example 1
Calculate the total solution needed and the injection rate for equipment setting/calibration
Step 1: total gallons of chemicals neededmultiply the total acres by the chemical solution to be applied (gal/ac)
Step 2: calculate injection rate in gal/hrdivide by the length of the chemigation event
Step 3: Convert gal/hr to milliliters per minute (ml/min)63.09 ml/min = 1 gal/hr
Step 4: set/check injector rate by injecting water for 1 minute
![Page 62: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/62.jpg)
Calculations ‐ Example 1
20 acres to be chemigated with ‐ 60 gal of solution per acre ‐ in one hour
Step 1: total gallons of chemicals needed20 ac x 60 gal/ac = 1200 gallons of solution
Step 2: calculate injection rate in gal/hr(1200 gal) divided by (1 hour) = 1200 gal/hr
Step 3: Convert gal/hr to milliliters per minute (ml/min)1200 gal/hr ÷ 63.09 = 19 ml/minute
Step 4: set/check injector rate by injecting water for 1 minute
![Page 63: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/63.jpg)
Calculations ‐ Example 2
Calculate injection rate based on concentration (ppm) of solution to be injected
.
IR = injection rate (gal/hr)F = flow rate of irrigation system (gpm)C = concentration of chemical wanted (ppm)P = Percentage of chemical in solution (%)
![Page 64: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/64.jpg)
Calculations ‐ Example 2I want to inject chlorine at a concentration of 5 ppm for one hour. My irrigation system has a flow rate of 100 gpm, and I’m using household bleach (5.25% chlorine)
𝐼𝑅 .
𝐼𝑅 0.006 100 𝑔𝑝𝑚 5 𝑝𝑝𝑚
5.25%
IR = 0.571 gal/hr of bleach
IR = injection rate (gal/hr)F = flow rate of irrigation system (gpm)C = concentration of chemical wanted (ppm)P = Percentage of chemical in solution
![Page 65: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/65.jpg)
Calculations ‐ Example 3
Determining amount of solution for fixed ratio injectors
For example 2, my venturi injector has a 100:1 ration
(injecting chlorine at a concentration of 5 ppm for one hour, a flow rate of 100 gpm, and using household bleach)
IR = 0.571 gal/hr of bleach
Step 1: Calculate total flow of irrigation system in one hour100 gpm x 60 min/hr = 6000 gallons per hour
Step 2: Calculate total gallons of solution to be injected (divide Step 1 by ratio)
6000 gph ÷ 100 = 60 gallons of solution
Step 3: Mix the 0.571 gallons of bleach with 60 gallons of water in the injection tank
![Page 66: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/66.jpg)
Chemigation Operation & Calibration Video Demonstration
![Page 67: Home - School of Irrigation - Vineyard Chemigation 2021...Requirements for water wells… All irrigation distribution systems … into which any type of chemical … or other foreign](https://reader036.vdocuments.site/reader036/viewer/2022071411/61068f0bd1eb302de233c0ba/html5/thumbnails/67.jpg)
Contact Information
• Dr Guy Fipps, PEProfessor & Extension Ag Engineerg‐[email protected]
• Charles SwansonExtension Program Specialist [email protected]‐845‐5614