Types of Wells: Dug, Driven, and Tube Wells

Groundwater is one of the most important natural resources for agriculture, dairy farming, and daily life – especially in countries like India, where over 60% of irrigated agriculture depends on it. But how does groundwater actually reach us? The answer, in most cases, is through wells. Wells are vertical structures dug or drilled into the earth to bring underground water to the surface. Not all wells are the same, though. Depending on how they are built, how deep they go, and how much water they can deliver, wells are broadly classified into three types: dug wells, driven wells, and tube wells. Each type serves a different purpose – from meeting domestic needs in a small village to supplying thousands of litres per hour to a dairy plant or an industrial facility.

Why understanding well types matters 🔗

Choosing the right type of well is not just a technical decision – it directly affects water yield, construction cost, water quality, and long-term sustainability. A small rural household needs a different setup compared to a large-scale dairy operation that requires consistent, high-volume water supply for cleaning, processing, and animal drinking needs. Tube well construction has expanded rapidly since the 1960s across India, allowing farmers to increase cropping intensity and sustain production through dry seasons. Knowing the differences between well types helps farmers, dairy operators, and planners make better decisions about water infrastructure.

Dug wells (open wells) 🔗

Dug wells are the oldest and simplest type of well. They are constructed by manually excavating the ground – either by hand or with basic machinery – until the water table is reached. Once dug, the walls are typically lined with bricks, stones, reinforced concrete blocks, or masonry to prevent the sides from collapsing.

Key characteristics of dug wells 🔗

Dug wells generally have a large diameter – ranging from about 2 to 9 metres – and a relatively shallow depth, usually not exceeding 20 metres. Because of their wide opening, they expose a large surface area to the surrounding aquifer, which allows water to seep in from the sides and bottom. However, their yield is limited. Open wells typically deliver a discharge of about 1 to 5 litres per second, which makes them suitable for small-scale domestic or agricultural use but insufficient for industrial or large dairy operations.

The construction cost of dug wells is low, which is why they remain popular in rural areas and small towns. In India, you’ll find dug wells across villages where they serve as a primary water source for households and small farms.

Types of dug wells based on lining 🔗

Dug wells can be further classified based on the type of wall construction used. Unlined wells are temporary structures where the sides are left exposed – these work only in compact subsoil and at shallow depths (typically 6 to 15 metres). Wells with pervious lining use dry brick or stone masonry without binding material, allowing water to enter radially through the wall. Wells with impervious lining use cement-mortar masonry, restricting water entry to the bottom only. There are also dug-cum-bore wells, where a borehole is drilled at the centre of a dug well to increase its yield by tapping deeper aquifers.

Limitations of dug wells 🔗

The biggest drawback of dug wells is their vulnerability to contamination. Since they are shallow and often lack proper sealing, surface runoff, agricultural chemicals, and waste can easily seep into the water. They are also prone to drying up during drought if the water table drops below the well bottom. Frequent disinfection is needed to keep the water safe for use.

Driven wells 🔗

Driven wells are another type of shallow well, but their construction method is quite different from dug wells. Instead of excavating a wide hole, a narrow-diameter casing pipe with a pointed tip is driven directly into the ground until it reaches a water-bearing layer of sand or gravel.

How driven wells are constructed 🔗

The pipe used is typically 2.5 to 15 cm in diameter. The bottom end has a sharp point – called a drive point or well point – that helps it penetrate the soil. The lower portion of the casing pipe is perforated to allow water to enter. This perforated section is usually covered with a fine wire mesh to prevent sand and soil particles from entering the well. The pipe can be driven using a wooden maul, drop hammer, or a machine.

Hand-driven wells typically reach depths of about 30 feet (roughly 10 metres), while machine-driven versions can go up to 50 feet or more. The entire process is relatively quick and inexpensive compared to drilling.

Advantages and limitations 🔗

Driven wells are simple and economical to construct, making them a practical choice for domestic water supply in areas with a high water table and soft, unconsolidated soil. However, their discharge is quite small – suitable only for household use or very small-scale agricultural needs. Since driven wells are not sealed with grouting material, they are vulnerable to contamination from surface water sources. They also cannot penetrate rocky or boulder-laden soil, which limits where they can be installed.

Tube wells 🔗

When the demand for water is high – as in factories, dairy plants, large farms, or municipal supply systems – tube wells are the go-to option. A tube well is essentially a long, narrow pipe (100-200 mm wide) bored deep into the ground to intercept one or more water-bearing strata. Unlike dug wells, tube wells have a small diameter (typically 80 to 600 mm) but can reach much greater depths – anywhere from 50 metres to 500 metres or more.

The key advantage of tube wells is their high yield. While a dug well might deliver 4 to 6 litres per second, a well-constructed tube well can deliver up to 200 litres per second, depending on the geological formation and the number of aquifers tapped. This makes them indispensable for industrial and large-scale agricultural use.

Strainer type tube well 🔗

This is the most common type of tube well – so common, in fact, that when people say “tube well,” they usually mean a strainer type. In this design, a perforated metal pipe is lowered into the borehole. Around this pipe, a fine wire mesh (strainer) is wrapped with a small gap between the mesh and the pipe. The strainer acts as a filter, allowing water to pass through while keeping out sand and soil particles.

Strainer sections are placed opposite the water-bearing formations, while plain (blind) pipe sections cover the non-water-bearing layers. This arrangement allows the well to tap multiple aquifers simultaneously, which significantly increases the total yield. The flow of water in a strainer well is radial – it enters from the sides through the screen.

Several types of strainers are used in practice, including Phoenix strainers (cadmium-plated mild steel with machine-cut slots), Ashford strainers (perforated tube with wire mesh soldered over it), and Brownlie strainers (polygonal steel plate with copper wire mesh). Sometimes, gravel packing is added around the strainer when the surrounding soil contains fine sand or silt, providing additional filtration.

Cavity type tube well 🔗

A cavity type tube well works on a different principle. It consists of a plain (blind) pipe – with no strainers – sunk through the ground until it penetrates an impervious clay layer and reaches the water-bearing formation below. During the initial stages of pumping, fine sand is drawn out along with the water. Over time, this creates a hollow cavity at the bottom of the well.

As the cavity grows, the velocity of water entering it decreases, and the sand stops coming in – leaving only clear water. The flow pattern in a cavity well is spherical (water enters from the bottom) rather than radial. The yield depends largely on the size of the cavity that forms. One limitation is that a cavity well can only tap one aquifer, unlike strainer wells that can access several. However, cavity wells are cost-effective since they don’t require expensive strainers or screens.

Slotted type tube well 🔗

When the subsoil conditions are not suitable for either a strainer or cavity well, a slotted type tube well can be used as an alternative. In this design, the pipe is plain for most of its length but has narrow slots cut at the bottom portion – typically about 5 metres long – which penetrates the confined aquifer.

The slots are usually about 25 mm × 3 mm with 10-12 mm spacing. To prevent sand from entering, a filter of gravel and coarse sand is packed around the slotted portion. Before removing the outer casing pipe, this gravel mixture is poured into the gap between the slotted pipe and the casing. Slotted type wells are particularly useful when the water-bearing strata are located at very deep levels and other well types aren’t feasible.

Perforated type tube well 🔗

Perforated type tube wells use pipes with small holes drilled directly into them. The perforated section is then wrapped with coir or jute rope, which acts as a makeshift strainer to filter out sand and fine particles. This is a simpler and more affordable construction method, though it may not be as durable or efficient as purpose-built strainers. Perforated wells are suitable where budget is limited but a basic tube well is needed.

Comparing dug, driven, and tube wells 🔗

Each well type occupies a specific niche. Dug wells are best for small-scale, low-cost rural water supply where the water table is close to the surface. Their wide diameter makes them easy to maintain, but their shallow depth and low yield limit their usefulness. Driven wells offer a quick and inexpensive solution for domestic use in areas with soft soil and a high water table, but they cannot handle large-scale demand. Tube wells are the most versatile and powerful option – capable of reaching deep aquifers, delivering high yields, and serving industrial, agricultural, and dairy operations reliably.

For dairy farms specifically, where water is needed for animal drinking, milk processing, equipment cleaning, and waste management, tube wells (especially strainer type) are typically the most practical choice. They ensure a consistent, year-round supply that doesn’t depend on seasonal rainfall or surface water availability.

Shallow wells vs. deep wells 🔗

Within the tube well category, there’s an important distinction between shallow and deep tube wells. Shallow tube wells typically go down to about 30 metres and draw water from the topmost aquifer. They are cheaper to install but produce lower yields and are more susceptible to contamination from surface water percolation.

Deep tube wells, on the other hand, can reach depths of 300 metres or more. They penetrate through impervious layers to access confined aquifers below, which typically hold cleaner, more reliable water. Deep wells can deliver discharge rates exceeding 800 cubic metres per hour in favourable geological conditions. For large dairy plants and industrial units, deep tube wells are often the preferred infrastructure investment.

The role of wells in India’s water landscape 🔗

India is the world’s largest user of groundwater, with an estimated 20 million borewells and tube wells across the country – up from just 1 million in the 1960s. About 89% of extracted groundwater goes to irrigation, making wells the backbone of Indian agriculture. However, this heavy reliance comes with serious sustainability concerns. The World Bank has warned that if current extraction trends continue, roughly 60% of India’s aquifers could reach critical conditions within two decades.

This makes it important not just to build wells, but to build the right type of well for the specific geological and usage conditions – and to pair well construction with sustainable water management practices like rainwater harvesting, managed aquifer recharge, and efficient irrigation systems.

Choosing the right well for your needs 🔗

The selection of a well type depends on several practical factors: the geological formation of the area (rock, sand, gravel, clay), the depth of the water table, the volume of water needed, and the available budget. For a small farm or household in an alluvial region with a high water table, a dug well or driven well may be perfectly adequate. For a dairy operation, food processing plant, or large irrigated farm, a deep tube well with strainer screens and gravel packing will deliver the reliability and volume required.

Consulting with a hydrogeologist or local groundwater authority before construction can help identify the best well type, optimal depth, and screen design for the specific location. Proper well development – including techniques like surging and gravel packing – is also essential to maximise yield and ensure sand-free operation over the long term.

What do you think? If you’re involved in farming or dairy operations, which type of well is currently being used in your area – and do you think it’s the most suitable option given your water needs and local geology?

References

1. https://www.worldbank.org/en/news/feature/2012/03/06/india-groundwater-critical-diminishing
2. https://www.science.org/doi/10.1126/sciadv.abd2849
3. https://testbook.com/civil-engineering/types-of-wells
4. https://wellowner.org/resources/basics/types-of-wells/
5. https://www.engineeringenotes.com/water-engineering-2/ground-water/water-wells/types-of-water-wells-groundwater-water-engineering/44350
6. https://en.wikipedia.org/wiki/Tube_well
7. https://www.yourarticlelibrary.com/water/tube-well/top-3-types-of-tube-wells-with-diagram/61092
8. https://ieg.worldbankgroup.org/blog/addressing-groundwater-depletion-lessons-india-worlds-largest-user-groundwater