Methodology
Our methodology for water well drilling in Fresno begins with a thorough hydrogeological evaluation, analyzing aquifer characteristics and seasonal water level fluctuations. We employ rotary drilling methods, including air and mud rotary, to penetrate the interbedded sands, gravels, and clays typical of the San Joaquin Valley. Borehole geophysics and sieve analysis guide screen selection and gravel pack design. Our team follows ASTM D1586 for standard penetration tests during pilot holes to assess formation density. For detailed aquifer testing, we conduct step-drawdown and constant-rate tests, analyzing data to determine specific capacity and transmissivity. This systematic approach ensures optimal well performance and compliance with California Department of Water Resources standards. Learn more about our water well drilling services.
Reference Technical Parameters
| Parameter | Reference Value |
|---|---|
| Predominant soil type | Alluvial sand, silt, clay, and gravel |
| Maximum seismic acceleration (PGA) | 0.4g (ASCE 7-16, Site Class D) |
| Typical groundwater level | 20–50 m below grade (varies seasonally) |
| Typical N60 range | 10–40 blows/0.3 m (variable by depth) |
| Aquifer transmissivity | 500–2000 m²/day |
Local Considerations — Fresno
Fresno’s subsurface is dominated by deep alluvial deposits from the Sierra Nevada, with interbedded sand and gravel aquifers separated by clay layers. The water table has declined significantly due to agricultural pumping, prompting stricter well permitting. Seismic risk is moderate (PGA up to 0.4g), requiring well casing and screen designs that withstand ground motion. Neighborhood contrasts exist: older areas near downtown may have shallower wells (30–50 m), while newer developments in the northeast often require depths exceeding 100 m. Typical projects include irrigation wells for vineyards and orchards, as well as domestic supply wells for rural subdivisions. Our team collaborates with local agencies to ensure compliance. For projects requiring specialized expertise, we also offer artesian wells in Fresno.
Request a Quote
Our team reviews your project and issues an initial report at no cost.
Or write us directly at contact@waterwelldrillingco.com
Services in Fresno
Applicable Standards
- California Water Code (Division 13)
- California Well Standards (Bulletin 74-81)
- ASCE 7-16 (Seismic Loads)
- ASTM D1586 (Standard Penetration Test)
- ASTM D5092 (Design and Installation of Groundwater Monitoring Wells)
Frequently Asked Questions
What types of soil are commonly encountered when drilling water wells in Fresno?
Fresno’s alluvial soils consist of alternating layers of sand, gravel, silt, and clay. Near the surface, fine-grained materials dominate, while deeper aquifers are coarser. Understanding these sequences is critical for screen placement and well yield.
How does seismic activity affect water well drilling in Fresno?
Fresno is in a seismically active region. Well casings and screens must be designed per ASCE 7 to withstand peak ground accelerations up to 0.4g. Proper grouting and annular seal placement prevent liquefaction-induced damage.
Are water well permits required in Fresno, and who issues them?
Yes, all water wells in Fresno require a permit from the Fresno County Environmental Health Department. Drilling must comply with California Well Standards (Bulletin 74-81), including minimum setback distances and construction specifications.