The depth of a tubewell is not a single, fixed measurement but varies significantly based on its type, geological conditions, and intended use, typically ranging from 35 meters to over 70 meters.
Tubewells are essential for accessing groundwater, and their design, including depth, is tailored to the specific aquifer and water requirements. They are generally categorized based on their construction and the depth to which they penetrate the earth to extract water.
Types of Tubewells and Their Depths
The concept of classifying tubewells by depth helps in understanding their capacity and application. These classifications often distinguish between wells designed for varying water yields and depths.
Medium Tubewells
Medium tubewells are designed to tap into shallower to moderately deep aquifers. These wells are suitable for various irrigation and domestic purposes where the water table is accessible at these depths.
- Depth Range: Medium tubewells typically have a depth in the range of 35 to 70 meters.
- Purpose: They are often used for small to medium-scale irrigation, drinking water supply for villages, and other community uses. Their construction involves either cavity tube wells or strainer tube wells, depending on the geological strata.
Deep Tubewells
Deep tubewells are constructed to reach deeper aquifers, often characterized by more consistent water availability and potentially better water quality. These wells are designed for higher discharge rates to meet larger water demands.
- Depth Range: Deep tubewells extend to a depth of 70 meters and more.
- Discharge Capacity: Due to their depth and design, deep tubewells are engineered to give a substantial discharge, typically ranging from 100 to 200 cubic meters per hour. This high capacity makes them ideal for large-scale irrigation projects, industrial water supply, and municipal water systems.
- Technology: These often involve more advanced drilling and casing techniques to ensure stability and efficiency at greater depths.
Summary of Tubewell Depths
To provide a clear overview, here's a table summarizing the classifications and their associated depths:
| Tubewell Type | Depth Range (Meters) | Typical Discharge (Cubic Meters/Hour) | Common Applications |
|---|---|---|---|
| Medium | 35 - 70 | Varies (Lower to Moderate) | Small to medium irrigation, village water supply |
| Deep | 70 and more | 100 - 200 | Large-scale irrigation, industrial, municipal supply |
Factors Influencing Tubewell Depth
The specific depth for drilling a tubewell is determined by several critical factors:
- Hydrogeological Survey: A thorough survey helps identify the depth, thickness, and water-bearing capacity of aquifers.
- Water Demand: The required volume of water dictates whether a medium or deep tubewell is necessary. Higher demand typically necessitates deeper wells with greater discharge rates.
- Water Table Fluctuations: Seasonal variations in the water table can influence the minimum effective depth required to ensure year-round water access.
- Geological Formations: The type of soil and rock strata (e.g., presence of hard rock, loose sand) affects drilling feasibility and the required depth to reach a productive aquifer.
- Water Quality: Deeper aquifers can sometimes offer better water quality, free from surface contamination, which might necessitate drilling to greater depths.
Understanding these classifications and influencing factors is crucial for effective groundwater management and ensuring sustainable water resources. For further details on groundwater resources and tubewell technologies, resources from organizations like the Central Ground Water Board of India or local water resource authorities can provide valuable insights.
