7/25/2019 Complete Guide on New Borewell Drilling AtoZ

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Complete Guide on New Borewell Drilling AtoZ

How to identify a suitable site for borewell?

Vertical Electrical Sounding is one of the very common geophysical methods used for

domestic borewell exploration. However, sufficient open area around the location is needed

for conducting the survey. Geologists charge around Rs.,!"" to !,"""#$ for identifying a borewell site. %ther methods of geophysical survey are used in special cases and they are

&uite expensive.

'ocal well diviners who use wooden stic(s or magnetic bloc(s are also to some extent

successful in identifying borewell sites. )ut this method may not be always reliable,

especially in areas where the geological formation is critical.

Is there a best suited time for drilling a borewell?

*s such there is no prescribed season for drilling a borewell if the location of site has

ade&uate ground water potential. However, identifying a suitable site and drilling the

 borewell in summer months would give the worst possible scenario in the location at the point of time. +herefore, summer months are usually preferred by some experts as the best

suited period for drilling a new borewell. *lso, as most agricultural sites can be accessed by

drilling rigs only during summer months, they are usually available in these periods.

What are the ommon methods adopted for drilling borewells?

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ethods of drilling to be adopted depends on factors li(e suitability of a method for a

 particular type of geological formation -i.e. such as alluvial, bouldery and hard roc(, cost

factors, diameter and depth of borewell and the purpose intended.

ost commonly used types of drilling methods are/

0ater 1etting $ Shallow bores in alluvial formations*ugur 2rilling $ Shallow bores in alluvial formations

3alyx 2rilling $ Shallow borewells in both hard roc( and alluvial formation

4ercussion 2rilling 5 2eep bores in bouldery formation

Rotary 2rilling $ ost common method used for drilling large and deep bores in alluvial

formations.

2own the Hole Hammering -2+H 2rilling 5 ost common method for drilling large and

deep borewells in hard roc( formations.

What is the standard diameter of borewells drilled for domesti purposes?

6or domestic purposes, 7.! and 8 inches dia borewells are usually drilled. 0hile 7.! inch ismost commonly drilled borewells for domestic purposes, 8 inch borewells are drilled when

higher yield is re&uired for large apartments or buildings and also for agricultural purposes.

9nitially larger diameter bits are used to place the casing pipes up to the hard roc( :one prior

to drilling specified si:e of the borewell.

How harges for drilling a borewell are usually alulated?

3harges for drilling a specified si:e of borewell include

drilling cost per feet,

cost of casing pipe per feet,

cost of drilling and installation charge for casing pipe per feet,

flushing charges per hour for flushing the borewell after drilling and

transportation charges of the rig to the site from nearest town per (m.

2rilling rates are sometimes charged in slabs for specified ranges especially when deep

 borewells are drilled. *s drilling rates usually vary depending on the availability of rigs, local

demand and site conditions, it is better to cross chec( with few drillers to get a competitive

&uote.

What are the types of asing pipes used in borewells?

3urrently, 4V3 pipes are very widely used as casing pipe. G9#ild steel casing pipes which

were used earlier are not being recommended due to the problem of corrosion. 4V3 casing

 pipes installed in borewells must confirm to 9S ;<<= >>; that governs the specification for 

unplastici:ed 4V3 screen and casing pipes for borewell of the )ureau of 9ndian standard.

+his standard covers the re&uirements of ribbed screen, plain screen and plain casing pipes of 

nominal diameter 7" to 7"" mm produced from unplastici:ed polyvinyl chloride for borewell

for water supply.

Slotted 4V3 casing pipes are used if a&uifer yields through sandy :ones to protect collapse of 

 borewell side walls and to prevent entry of fine sand into the borewell which might clog the

 borewell. +his re&uires detailed study by Geologists to decide slot si:e and at what depths

these have to be provided along with gravel pac(ing around the casing pipe.

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What is the safe distane between a borewell and septi tan!"soa! pit?

aintaining sufficient distance between a borewell and septic tan( is always recommended

as there are chances of contamination. 9f the situation warrants location of them in close

 proximity, it advisable to properly grout the borewell casing pipe with cement slurry till hard

roc( formation. 9n shallow a&uifer :ones, it is not advisable to locate borewells used fordrin(ing purposes and the septic tan( in close proximity. 9t is better to ta(e professional

assistance in such cases to ta(e preventive steps around the borewell as well as the septic

tan(.

Normal rate#

8.! inch bore

"$;!" feet $? Rs 8;

;!"$@!" $? Rs A;

@!"$7!" $? Rs <;7!" $ !!" $? >;

!!" $ 8!" $? "A -Rs ! increase

8!" $ A!" $? ;;

A!" $ <!" $? @A

<!" $ >!"$? !A- Rs ;" increase

>!" $ <8"$? AA

S 4ipe-Ainch dia , ;.! mm thic(ness, 8Bg per cms& strength $? Rs @;" per feet

-@ diferent thic(ness= ;mm$Rs.;A"#ft,;.!mm$Rs.@;"#ft,@mm$Rs.@>"#ft

PVC pipe(10 inch dia) -> Rs 300 per feet (Starts from Rs.200/feet)

S 3ollar and 0elding charges per Coint $ Rs @"" -!" for collar and !" for welding -every

;" feet

8#;D 2ia cap ""

Lao!r and "ransportation char#es Rs. 1000

6or >!" feet bore it will ta(e ; days

$eleting %ump#

6irst read this=

How to calculate the H4 of the water pump

ou might have found that there are only two variables re&uired to calcuate the water pump

H4. height of total lift of water ; re&uired flow 4lease ta(e total height in meters and flow

re&uired in liter per minute. now multiply height-in meters and flow -in liters per minute

now divide this by 7!"" you will get theoretical H4 of the pump.

 Fow there is a secret to calculate actual H4 of the pump 9n my practical experience i did not

find pump efficiency more than @" . 9n most cases it is less than @" . So to calculateactual H4 you should multiply theoretical H4 by 7. *ctual H4 is 7 times more than theoretical

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H4.

Second secret, 4lease calculate total suction lift from pump to sump bottom. please ensure

water pump is capable of producing so much suction.

+hird secret, please add ;" to your actual height of water lift. +hese are called frictional

losses.

6ourth secret, submersible pumps are more efficient than monobloc( pump.

ono bloc( pump $usually Rs.!"""-.!H4

Submersible 4ump$sually ;!"""-.!H4

+ips=

. +ry to find @ phase availablity in your street.

;. 2o you re&uire really @ phase or single phase pump B0 - @ phase deposit is higher than

Single phase, 9 thin( for monthly bill be same for @ phase or Single phase. 3hec( with pump

expert.

@. Spea( with nearby house people having bore, to (now about water availablity during

summer. -0hich helps to select the pump Sometimes, if you go for higher suction power

motor and if your bore canIt yield for the motor capacity it will be problem.

7. *nyway have pipe routed to Sump J %H+ with control valve. 9t will helps during summer

time, if your bore or pump losses it efficieny.

!. +ry to avoid number of bends at delivery line from bore.

4lease place the borewell motor at ;" to @"ft from the bottom point of the borewell in case ifthe yield falls down too u will not face a problem in the water supply. if you place at 7"" ft

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and yield is less in summer then you have to rewor( to down the motor further and if motor

runs without water there is a ris( of motor failure.

*s one time effort place the motor at maximum best point. 2ont loo( at the pipe and wire

cost, 2o it right at the first time, )e pessimistic for this wor( 

H24E 4ipe= Rs.8@#m -eg=;A" feet Rishi brand6inolex cable= Rs.8"#m -eg=;>" feet,;"feet extra

.!hp !stage single phase texmo submerged nearly ;!"""

+otal cost for @"" feet borewell @!""-Fot for drilling borewell,only pump and installation

charge

2ifferent 4ump brands=

+exmo -)est in 9ndustry

3R9

4E0

Suguna Submersible 4ump vs onobloc pump vs *ir 3ompressor 4ump

V$Guard

0hat is good 0ater ield= ore than ;D K

http=##www.derm.&ld.gov.au#factsheets#pdf#water#w7.pdf 

Water &an!s -%ver head and nder Ground

)est brand= Sintex

3apacity= ;""litres per day is the average consumption of 9ndian peoples

9f 7 people living in a house and every ; days water need to be filled then ;L7L;"" M

8""lires.

;"""litre tan(s are idle.

4rice = Formally Rs.8 per litre.

So ;""" litre tan( price nearly ;""