The EMAS Drilling Method
The EMAS (Escuela Móvil de Agua y Saneamiento / Mobile School for Water and Sanitation) method is a highly efficient manual drilling technique developed by Wolfgang Buchner in Bolivia. It is specifically designed to allow low-income households and local operators to construct their own water wells and sanitation systems for a fraction of the cost of commercial mechanized drilling.
What is the EMAS Method?
The EMAS method is a hybrid technique that combines jetting (fluid circulation), percussion (pounding), and rotary action (rotation). The drilling process is performed manually using lightweight, inexpensive materials.
- Hybrid Mechanics: The operator uses a lever/handle attached to the drill pipe. The drill string is rotated back and forth while being lifted and dropped (percussion). Simultaneously, water is pumped down the inside of the drill pipe (jetting) using a manual hand pump.
- Fluid Circulation: The water pumped down the drill pipe exits through the drill bit, fluidizing the sand or loosening the clay. The water then carries the soil cuttings up the outside of the drill pipe (the annulus) to a small settling pit at the surface. The water is then recirculated.
- PVC Integration: Standard galvanized iron pipe is used for the main drill stems, but the final well casing is made of inexpensive PVC pipe.
- Borehole Size & Depth: EMAS typically drills a narrow borehole of about 2 to 3 inches in diameter, reaching depths of 40 to 90 meters in favorable geologies.
Geological Suitability
- Ideal Substrate: Loose sands, soft silts, alluvial deposits, and cohesive clay.
- Disqualifying Substrate: Solid bedrock, granite, basalt, sandstone, or dense boulder fields. The manual hybrid force cannot fracture hard formations.
- Water Table: Perfect for shallow to medium aquifers where manual pumping remains viable.
Sourcing & Pump Compatibility
Because the EMAS borehole is narrow (~2 inches), it cannot accommodate standard wide community handpumps like the Afridev or India Mark II. Instead, it is paired with the EMAS PVC Flexi-Pump, a specialized, low-cost manual pump made of standard PVC pipe and check valves, which is fabricated on-site by local operators.
Technical Resources & References
- Rural Water Supply Network (RWSN): Access the RWSN library for manual sector professionalization guides and case studies.
- EMAS International: Technical drawings, manuals, and instructional videos on rig fabrication and PVC pump assembly.