California pump & production
Every well owner is interested in how much water their well will produce and how dependable the production will be with time. To make that determination a production test must be made. Usually this involves pumping at the expected production rate over a certain length of time (usually 4 hours). There is considerable variation in actual practice on how such tests are performed depending on the dimensions of the well, including expected capacity and intended use as well as geologic conditions at the site. Obviously, for a small capacity well, i.e., one that produces under 50 gallons per minute, the test would not be as elaborate as it would be for a high capacity well, but is no less important.
The amount of water needed is determined by the intended use of the water. For example, on the average, each person in a household uses between 50 and 100 gallons of water a day. To the daily household use must be added seasonal uses such a lawn and garden irrigation, swimming pools, etc. Thus, a well supplying one to four gallons per minute is a reasonable amount for a single family dwelling but may need a water storage system to accommodate higher flow rates required at any given time. A well must produce a minimum of one gallon per minute to be considered a viable well. The well must produce 1,200 gallons over a four hour open discharge flow condition to meet state requirements. If this 1,200 gallon rule is not meet, a storage system may be install to meet the requirement. Additional amounts, for watering livestock or irrigating small acreages of crops, must be added to these values.
Most lending insitutions will require a certified well production test along with a full system inspection and water potability test prior to closing.