Three methods of measuring and estimating irrigation pumpage were used during two research studies attempting to assess ground-water use. These three methods: (1) farmer estimates; (2) rain gauges; and (3) two flowmeters, are discussed and evaluated. None of the methods were completely reliable. Farmer estimates may be inaccurate due to well or pump deterioration or system modifications. However, these estimates do help verify values found by other methods. Rain gauges are individually accurate, but they cannot predict spray variations or differences in farmer irrigation practices in a field. The ultrasonic flowmeter was inconsistent due to varying field conditions. Though accurate in the lab, repeatability is required in the field to verify data. The intrusive flowmeter was consistent but did not agree with farmers estimates.