# Select a Calculator

These irrigation calculators will help compute your irrigation needs based on your growing practices, types of soil, and vegetation.

##### Sprinkler Calculators

- Hand Move Sprinklers: Find recommended values for hand move sprinklers, such as set times, nozzles and pressure losses.
- Sprinkler Density: Find the number of sprinkler heads per area for rectangular or triangular spacing.
- Sprinkler Discharge Rate: Learn how to estimate a single sprinkler's discharge rate by setting up an experiment using two sprinklers, 4 cans and a measuring container.
- Traveling Big Gun Sprinkler: Calculate the net water application for a given flow rate, efficiency percentage, lane width, and travel speed.
- Traveling Sprinkler: Estimate the the total number of irrigated acres per hour based on lane spacing and travel speed.

##### Center Pivot Calculators

- 1" Application Time: Calculate the irrigation time to apply one inch of water with a center pivot.
- Center Pivot Acreage: Calculate the area underneath a center pivot.

- Percent Timer Setting: Use this calculator to calculate an approximate timer setting to apply a particular depth.
- Pivot Full Rotation Time: The time that it takes for a 360 degree rotation of a center pivot.
- System Pumping Requirements: Calculate the system capacity (flow rate) required to meet the demands of a field.

##### Chemigation Calculators

- Batch/Bulk Application: Calculates the chemical injection rate for batch or bulk chemical applications.
- Calibration: Calibrate your injection pumps by calculating the estimated fill time of a container using the pump's injection rate.
- Chemical Injection Rate (Mass): Calculate the injection rate based on the weight per area.
- Chemical Injection Rate (Volume): Calculate the injection rate based on the volume per area.
- Chemical Injection Rate (Water Chemistry Control): Calculate the the injection rate for water chemical solutions.
- Maximum Solution Concentration: Find the solution concentration in the irrigation lines for a given chemical injection rate and water flow rate.
- Mixing Dry Chemicals: Calculate how much dry chemical to mix with water, depending on your water requirements.
- Quantity Per Sprinkler Setting: Determine the irrigated area, and either the fertilizer or the herbicide application based on the characteristics of the area's irrigation system.

##### General Calculators

- Field Area: Find the areas for rectangular, triangular, circular, and trapezoidal field areas.
- Fitting Pressure Loss: Estimate the equivalent pipe length of plastic IPS or copper type fittings.
- Irrigatable Area: Determine the irrigatable area based on your minimum system capacity.
- Irrigation Frequency: Calculate the maximum time between irrigating an area.
- Irrigation Run Time: Find the length of time to run an irrigation system to replace water lost to evapotranspiration.
- NPSHA: Determine the atmospheric pressure of the irrigation system and ensure a system's "Net Positive Suction Head Available" exceeds the "Net Positive Suction Head Requirement".
- Pipe Size Estimate: Estimate the circumference of the inside of a pipe
- Pipe Velocity and Diameter: Many designers design pipe sizes based on velocity limits (5 fps). Calculate the pipe diameter and the water velocity in the pipe.
- Pipeline Pressure Loss: Pressure loss in pipes from friction.
- Pipeline Pressure Rating: Find the maximum operating pressures.
- Pipeline Pressure Loss with Outlets: Calculate the pressure loss in a pipe with evenly spaced outlets, such as a sprinkler lateral or a manifold, or minimum pipe size in the same based on the maximum allowable pressure loss.
- Required Maximum Flow Rate: Flow rate required to meet crop water demands for an area.
- Required Water Pump Horsepower: Calculate the horsepower requirements for a pump.
- Set Times: Calculate the set time for irrigating based on application and flow rate.
- System Capacity: Estimate the required system capacity using the characteristics of your field, such as its area, depth and operation time.
- Total Dynamic Head: Determine the total dynamic head pressure, and existing head.
- Water Application Rate: Water application rate from a given flow and area.
- Water Depth: Calculate application depth given flow, land area, and time.
- Water Hammer: Find the total developed pressure due to a sudden shutting of a valve or the water hitting the end of the pipe.
- Water Supply Design: Estimate the minimum water supply requirements and total system capacity requirements for your system.

##### Water Measurement Calculators

- 90º Triangular Notch Weir: Find the flow rate of a triangular notch weir, based on its height.
- Cipolletti Weir: Determine the flow rate of a Cipolletti weir, based on its length and height.
- Parshall Flume: Estimate the flow rate of a Parshall flume based on its throat width and height change.
- Rectangular Contracted Weir: Find the flow rate of a rectangular contracted weir based on its length and height.
- Rectangular Submerged Orifices: Calculate the flow rate for a rectangular submerged orifice based on its area and height difference.
- Trapezoidal Flume: Determine the flow rate of a trapezoidal flume based on its height difference and bottom width.
- Trapezoidal Weir: Calculate flow rate over a trapezoidal (Cipolletti) weir.