Well Drilling in Fresno County, CA

• Coverage includes Sanger, Reedley, Selma, Kerman, Kingsburg, Caruthers, Laton, Auberry, Prather, Tollhouse, Friant and Shaver Lake.
• Crews work along SR 99, SR 41, SR 168, SR 180 and I-5.
• Inside incorporated cities, contact the city about wells; the county permit covers unincorporated areas.
• Before you call: know your subbasin and its Groundwater Sustainability Agency, and whether the lot is inside a city, since the city then handles the well instead of the county.

• Replacement wells for domestic wells that went dry in drought
• Deepening wells as valley water levels fall
• Foothill wells in fractured granite
• Pump and tank work
• Well destruction for abandoned wells, which the state standards require
• Water sampling after a new or deepened well

• Local depth: at the USGS median of about 240 ft, the site calculator's formula gives $7,500–$20,100 for a complete well. The site calculator's method is depth × $25–$65 per foot, plus permit $200–$500, pump $900–$2,500 and tank $400–$1,500. It is an estimate, not a quote. The USGS record for Fresno County mixes 5,209 domestic, irrigation and monitoring wells, and its 75th percentile (about 1,143 ft) reflects deep farm wells, so it isn't a good guide for a home well.
• Annular seal: the county says the California Well Standards require a seal at least 20 feet deep, and county staff inspect it, so plan for a 48-hour scheduling notice.
• Water levels: wells in critically overdrafted subbasins may need to go deeper than older neighbors, and the local Groundwater Sustainability Agency can set limits on use.
• Foothill rock wells around Auberry and Prather depend on fractures, so yield varies widely between lots.

• Step 1, permit: a C-57 licensed contractor applies through Fresno County's Citizen Portal with a plot plan and fee. Fresno County Ordinance Code, Title 14, Chapters 14.04 and 14.08, and the California Well Standards (Bulletins 74-81 and 74-90) apply.
• Step 2, GSA check: the county says to contact the Groundwater Sustainability Agency for your subbasin before drilling, since the GSA regulates use of the well.
• Step 3, seal: the county requires the driller to give 48 hours' notice before installing the annular seal, which must be at least 20 feet deep.
• Step 4, report: the Well Driller's Report is due to the county within 30 days of completion. Fresno County then schedules a final inspection and, for domestic wells, free water sampling.
• Step 5, timing: the permit is valid for 180 days. Fresno County sets the fee in its Environmental Health fee schedule; until you confirm it, the site calculator budgets $200–$500.

• Valley alluvium: USGS site records code most Fresno County wells to the Central Valley aquifer system, layered sand, gravel and clay deposited by Sierra rivers; the foothills east of Friant are granite.
• Reading the log: on the valley floor, the alluvium of the Central Valley aquifer system is layered sand, gravel and clay, and on the west side the Corcoran Clay layer separates an upper and a lower aquifer zone. East of SR 99 and toward the Sierra foothills, alluvium thins and wells pass into granite bedrock, where water comes from fractures rather than a continuous aquifer.
• USGS site records (n=5,209 with depth): 25th percentile about 100 ft, median about 240 ft, 75th percentile about 1,143 ft, 90th about 1,930 ft. The deep end is mostly irrigation and municipal wells.
• Overdraft: the county says its critically overdrafted subbasins must be sustainable by 2040 under the state groundwater law, which drives GSA rules.
• Water quality: Fresno County publishes guidance on nitrate, DBCP and gross alpha in well water, all found in parts of the county.
• Census ACS counts about 344,894 housing units with a median year built of 1982.

Sanger · Reedley · Selma · Kerman · Kingsburg · Caruthers · Laton · Auberry · Prather · Tollhouse · Friant · Shaver Lake