| BCR | Benefit Cost Ratio |
| Bi | Benefit flow of the i year |
| Ci | Cost flow of the i year |
| D | Inside diameter of the pipe |
| Є | Electrical efficiency |
| Eh | Hydraulic energy |
| ea | Actual vapor pressure |
| es | Saturated vapor pressure at air temperature |
| Esi | Space between emitter or sprinkler |
| Etc | Crop evapotranspiration |
| Eto | Reference evapotranspiration |
| f | Darcy-Weisbach resistance coefficient |
| FC | Field Capa city |
| G | Soil heat flux density |
| g | Gavitational acceleration |
| GIR | Gross Irrigation Requirement |
| Hd | Dynamic high |
| Hp | Pressure head |
| Hem | Pressure needed at the emitter |
| hf | Head loss |
| hf1 | Head loss from the pump to the most unfavorable supply inlet |
| hf2 | Head loss from the inlet to the most unfavorable emitter |
| Ho | Number of hours of operating time |
| IRR | Internal Rate of Return |
| J | head losses in percentage |
| Kc | Crop coefficient |
| L | Pipe length |
| ρ | Water density |
| Lli | Lateral length |
| Lri | Mainline length |
| Lsi | Space between lateral |
| n | Time frame of the project |
| NIR | Net irrigation requirement |
| ηpum | Overall pumping plant efficiency |
| NPV | Net Present Value |
| PBP | Payback Period |
| Peff | Effective rainfall |