Overview
ISO 22282-4:2021 - Geotechnical investigation and testing - Geohydraulic testing - Part 4: Pumping tests defines requirements for planning, executing and reporting pumping tests used in geotechnical investigations. It applies to pumping from wells in soils and rock and to aquifers whose permeability allows a measurable lowering of the piezometric head within hours or days. The standard is intended to support assessment of aquifer and well parameters (for example permeability, radius of influence, pumping rate, drawdown, skin effect, well storage and recovery), and is to be used in accordance with EN 1997‑1 and EN 1997‑2.
Key topics and technical requirements
- Scope and applicability: pumping tests on aquifers with short- to medium-term hydraulic response; soils and rock.
- Equipment: requirements for a test well and piezometers (ISO 18674‑4), pumps and pipework, calibrated discharge-measuring systems, water-level measuring devices and accurate timing.
- Test planning: siting, required drawdown/discharge, water disposal arrangements, and discharge-rate estimation (including methods in Annex B).
- Well design and installation: minimum penetration into saturated zones, well diameter, screen length and filter material to accommodate pumping and measurement.
- Test procedure: pre-pumping monitoring, preliminary pumping, controlled pumping phase, post‑pumping recovery monitoring, handling interruptions, uncertainty of measurement and decommissioning.
- Data and interpretation: measurement recording, evaluation of hydrodynamic parameters (transmissivity, storage coefficient), assessment of skin effect and well storage; guidance on interpretation is provided (see Annex C).
- Reporting: field report, installation records, measured values and a formal test report with results and methodology.
Practical applications
- Characterising groundwater flow and aquifer properties for foundation design, dewatering design, tunnel and excavation projects.
- Estimating sustainable pumping rates and radius of influence for construction dewatering or water supply wells.
- Evaluating well performance, well rehabilitation needs, and effects of pumping on nearby structures or groundwater bodies.
- Supporting hydrogeological modelling and risk assessments tied to geotechnical design.
Who should use this standard
- Geotechnical and hydrogeological engineers
- Site investigation contractors and drilling subcontractors
- Environmental consultants and groundwater specialists
- Design teams working to EN 1997 (Eurocode 7) and project stakeholders needing validated aquifer parameters
Related standards
- ISO 22282‑1 (General rules for geohydraulic testing)
- ISO 18674‑4 (Piezometer installation and pore pressure measurement)
- EN 1997‑1 / EN 1997‑2 (Eurocode 7 geotechnical design and investigation)
Keywords: ISO 22282-4:2021, pumping tests, geohydraulic testing, geotechnical investigation, aquifer permeability, drawdown, piezometric head, transmissivity, well storage.