What is well yield (GPM)?

Well yield, expressed in gallons per minute (GPM), describes how much water a well can deliver on a sustained basis. This measurement reflects both the recharge rate of the aquifer and the capacity of the formation to yield water under pumping conditions. A well might have excellent water quality but poor yield, or vice versa, so the two are distinct properties.

Yield matters directly when choosing a pump. If a well produces only 5 GPM but you install a pump rated for 15 GPM, the pump will run longer, cycle more frequently, and pull the water level down past the pump intake, causing equipment strain and potential dry-well conditions. Conversely, undersizing the pump means slower water recovery and insufficient pressure for household use. Bonner County wells vary widely in yield depending on geology, depth, and seasonal water tables, so knowing your well's actual output is essential before any pump repair or replacement.

Well yield is typically determined through a pump test conducted over several hours. A qualified technician measures how many minutes the water level takes to recover after pumping stops, or records the steady-state gallons per minute during a set drawdown. Seasonal fluctuations are common in Idaho, and yield may drop during dry summers or recover in spring runoff. If you need help assessing your well's yield or sizing a replacement pump, well pump repair providers in the area can test and advise.