Frequently Asked Questions on Borewell Drilling
1. How to find underground water?
Groundwater is present beneath Earth’s surface in pore spaces and crevices of rock formations. When you intersect them with drill then we get sufficient underground water. Different methods are applied to find underground water. Groundwater is stored in and moves slowly through geologic formations of soil, sand and rocks called aquifers.
The water beneath earth’s surface moves in various veins and streams. They are surrounded by certain forces. When the water connects via these forces, with the device held by the geologist, there is response and we can detect the presence of underground water. Popular methods in finding underground water are
The hydrologists or the geologists uses a forked stick dowsing rod and walks through the field with the dowsing rod. When he walks over a location that has the potential of yielding water, the dowsing rod will rotate in his hands and point toward the ground.
2. L-shaped rods
The L-shaped rods held by the geologists turn their direction when they connect with the water beneath the underground.
The coconut laid flat in geologists’ hand, turns upright when coming in close proximity to underground water. For more information here- “ how to find underground water ”.
2. How to determine yield of borewell?
Yield of existing borewell is determined by the borewell flushing outflow of water measured with V-notch plate at 90 degree. Nowadays, camera scanning can be done to find the depth of water as well as different rocks giving source of water.
Yield is determined by the relation between amount of water pumped out of the well on usage and the amount of water recharging the borewell from the surrounding underground water from surfaces and rocks.
Geologists and Hydrologists with water diviner method or through geophysical survey are able to determine 90% about the yield of borewell but can’t guarantee 100%.
3. Did you know, industries to pay for groundwater extraction from June 9?
According to indiawaterportal.org ,
The Central Groundwater Authority (CGWA) has issued new guidelines for groundwater extraction to conserve groundwater. As per the new notification, a water conservation fee (WCF) would be levied on industries for extracting groundwater from June 2019. The notification would be applicable to mining, dewatering units, packaged drinking water units, individual households with a delivery pipe of greater than one inch in diameter. The agricultural sector, however, would be exempted from the fee. Also, industries will need to apply for a no-objection certificate (NOC) online through a web-based application system of CGWA.
1. How to find exact site for drilling borewell?
When we dig borewell, once we hit the hard rock while drilling, we get water that becomes the permanent source of water that is safe for drinking.
Water divining method is found to be successful in most of the cases of finding exact site for drilling borewell. In limestone terrains, one can find good source of underground water. An expert finds two to three intersections of underground water veins through this method – water divining.
Water dependent plants like cottonwoods or willows indicate groundwater at shallow to moderate depth. Hydrologists find such clues to find exact site for drilling borewell. Geologists take the help of maps showing the distribution of different types of rocks in various positions. It helps located aquifers with uniform permeability of water.
2. What is the best time to drill borewell in Bangalore?
· The best time to drill borewell is from the months of January to August for agriculture and all-around Bangalore. Urban years up to 35kms has ample amount of water storage availability.
· Most agricultural sites can be accessed by drilling rigs only during summer months and hence are usually available in these periods.
· During rainy season, static water is up to 50 ft and during summer season, the static water is up to 100 ft.
· During summer months, if the hydrologists or geologists are able to find the source of water, that defines the longevity of the well. Yield of wells is generally low just before the onset of monsoon, a real picture of well yields will be obtained by constructing wells in that season.
3. What are the methods to drill a borewell?
· Drilling borewell of 6½-inch is the common practice in hard rock areas and 8 ½ -inch for Bangalore soil conditions.
· Blank casing pipe is installed until the hard rock. No further piping is installed, so that only clear water free from unwanted particles enter the borewell from the crevices or other sources of water in the surroundings.
· The casing pipe is installed in such a way that muddy water doesn’t enter the borewell harming the purity of the clear water used for drinking purpose.
· Tube well drilling requires more extra effort while installing the pipes to avoid finer material in the aquifer entering into the well through screen filters. We need to select the correct size of the screen filters or we need to develop the well by excessive pumping flushing out water containing unwanted particles.
Most commonly used types of drilling methods are: Source www.indiawaterportal.org
Water Jetting - Shallow bores in alluvial formations
Augur Drilling - Shallow bores in alluvial formations
Calyx Drilling - Shallow borewells in both hard rock and alluvial formation
Percussion Drilling – Deep bores in boulder formation
Rotary Drilling - Most common method used for drilling large and deep bores in alluvial formations.
Down the Hole Hammering (DTH) Drilling – Most common method for drilling large and deep borewells in hard rock formations.
4. What is the cost of drilling borewell?
The drilling cost of borewell depends the depth of the borewell where the underground water level is reached. The drilling cost is calculated with the following factors
· depth of the borewell reached
· cost of casing pipe per feet
· cost of installation of the pump and drilling
· flushing the borewell cost
· transportation charges of the rig unit to the site per km
You can check with borewell drillers near you to get competitive quote that works best in your budget. Get free quotes and connect with the best borewell drilling contractors .
5. What will be the quality of drinking water in borewells?
The borewell drilled in hard rock areas contains water free from bacteria or chemicals. After the borewell is drilled the water is tested for chemicals and bacteria.
Water can be tested in government approved labs for free also. Filtration and other water treatment methods are used to remove any impure substance present in the water and to improve the quality of water.
6. How far the borewell must be dug from the septic tank?
A minimum of 15ft from septic tank, one can dig the borewell. After drilling for the borewell, unwanted and unusable water are first flushed out and only the water that is drinkable enters the borewell for further usage.
7. What are the services offered by Borewell drillers?
. Tubewell drilling
Borewell drilling services offer wide variety of customer service to address every customer’s pain points with respect to borewell pumps.
1. How to recharge my borewell?
Dry borewells can be recharged by rainwater.
1. Collection of rainwater – a pond or pit is created for collection of water in ground level, next to borewell site in such a manner so that it can collect the monsoon rains. One can even go with roof top method for collection of rain water.
2. PVC or Galvanized Iron Pipelines carry such monsoon rains towards the borewell site.
3. Filter the Impurities and other pollutants in the rainwater.
4.The first runoff water is discarded and then water that comes later are in natural form.
5.The purest form of rainwater is then transferred to borewell. This can be used for drinking, growing food and use for household needs.
Recharging your dry borewell has got multifold benefits.
1. What is Tubewell drilling?
§ Tube well drilling is used in soft rocks or alluvial soil
§ Casing of the tube is Galvanized iron
§ Tube well goes deep down further from the ground level
§ Tube well works under lift irrigation
§ The strainer fitted at the bottom of the pipe helps avoid subsoil particles entering the pipe
§ Velocity of the water is very high to keep the pipes surroundings clean within.
Installation of Pumps
1. What are the types of casing pipes used in borewells?
· MS Pipe type of casing pipe is installed up to hard rock
· PVC Casing pipe is installed up to lose soil
2. How to choose the right pump for a borewell?
The right pump for a borewell can be determined by the depth at which the pump is installed and desired output of the water. Usually the depth of the borewell will be 10-25 ft. The type of casing pipe is selected based on the hard rock or lose soil configuration.
4. What are Robo Borewells?
Robo borewells are applicable for house that is already built or constructed. For small congested areas Robo borewells are the best choice to easily drill and install borewells. They are also known as Gas Borewells.
5. What type of Borewells are used for Drilling?
Robo Borewells - For buildings or residence already constructed
Sensor Borewells – High tech Sensor borewells are used for vast open site that is vacant .