Water is a pressing need all over the world. Exponential rise of population triggers exponential consumption of water. Municipal water storage and supply scheme failed to provide significant amount of water in urban areas. Water scarcity is spreading exponentially as water is needed to grow and process food, create energy, and serve industry for a continually growing population. This scenario prompts the populace towards boring activity to get excess quantity of water. Due to excessive groundwater pumping through boring for agricultural, urban and industrial uses, discharge rate is increasing at faster rate than local recharge and resulting in declining water tables and leading cause of scarcity.  Basically, scarcity are manifestations of climate fluctuations, conceived as variations around an average. Those variations are associated with large-scale anomalies in the planetary circulation of the atmosphere, which in the tropics lead to the subsidence of air masses and therefore the absence of precipitation.  Large-scale anomalies, when they affect an area, tend to produce drought in various phases of the water cycle, which is reflected both in soil moisture deficiency and in a lack of groundwater recharge.

Karachi is the largest and most populated city of Pakistan. Residents of this megacity have to face severe difficulties to get fresh water. The tanker mafia are stealing water from water supply infrastructure. The people are compelled to purchase fresh water by tanker mafia. Domestic users are not well-off enough to purchase water even though after paying the high amount they are getting boring saline water. Because mostly market venders hydrant are selling boring water. The water scarcity in Karachi lead to drilling of large number of boring. These water wells are continuously pumping water out of subsoil stratum. Due to rapid increase in nos. of borings withdrawal of boring water increases 1000 times but the recharging source of groundwater table is still same. The rate of pumping out of water is much greater than the rate of recharge of these water wells. The unsustainable ground water usage results in further lowering of ground water table. Perch aquifers are drying and degrading deeper. These unplanned boring effect the domestic users. It is their compulsion to drill deep borings which is cost and time effective. The pumping level are often high enough to cause seawater to invade fresh water aquifers. It increases salinity and damage the quality of water for domestic and industrial use.

One of the other consequences of this high draw down level is soil subsidence. Residents of some areas of Karachi have recently experienced localized earth quakes. These localized earth quakes are most common in Gulistan e Johar and other adjoining areas of Karachi with large number of flats and other high rise buildings. The high water demand of these high rise buildings cannot be met through KW&SB supplied water. As a result, the residents resort to drilling of water wells. As explained earlier, the high usage of ground water leads of lower water table. Lowering of water table leads to lower pore water pressure. The absence of water from soil matrix results in creation of vacuum and this phenomenon leads to soil subsidence. When soil particles rearrange themselves to account for the soil subsidence, settlements of foundations takes place. High rise buildings have higher design loads and therefore the effect of soil subsidence is most pronounced on high rise building’s foundations. Their residents feel like they have experienced an earthquake due to the shaking of subsoil surface associated with soil subsidence. It may damage infrastructure like bridges, highways, electric power lines and underground pipe lines.

So, being an accountable hydro geological firm this is the major responsibility of BNB to suggest a proper solution, planning and regulation for domestic/industrial boring. BNB suggest the industrial users to drill deep boring till confined aquifer and leave the perch/unconfined shallow aquifers for domestic boring. Vertical urbanization i.e. high raise building/flats should also drill deep boring for long term boring water availability.

Demand for industrial and drinking water have multiplied in recent years. Water is required for numerous tasks in domestic and in business enterprises. Purchasing your private well can offer a low cast alternative. To provide well drilling services various Well drilling Contractors are working in the field but most of the Well drilling Contractors are not working in proper geological manner. In order to provide low cost water well, high discharge with low TDS and also make an individual worth in this field, BNB set a new trend among all local Well drilling Contractors and introduced a new drilling technique i.e. Aquifer Horizon Segregation (AHS) method.

BNB surveyed industrial areas of Karachi to acquire knowledge regarding water well and observed that majority industries getting ground water from lower depth with very high TDS and extremely contaminated, which was drilled and poorly designed by unprofessional Well drilling Contractors.

BNB stand the new SOP for drilling a tubewell, through electrical resistivity survey, which is specialized job, which only few Well drilling Contractors can execute. BNB interpreted deep aquifer with low salinity. In AHS method BNB drilled deep-water wells, demarcate various aquifer horizons as per lithological and geophysical logging interpretation. In order to withdraw low TDS ground water with significant discharge BNB suggested sealing upper aquifer horizon, which was contaminating ground water. Henceforth, BNB makes it standard practice for industrial water well drilling and introduce in its marketing strategies.

BNB also emphasis the industry to stop their failure attempt with unprofessional Well drilling Contractors, which cost the enormous loss in aspect of capital and precious effort with local Well drilling Contractors to accomplish what they can not promise. Industry have to look forward to qualified Well drilling Contractors having skilled team of geologists and hydrogeologists to ensure the 100 percent results of their capital and time.

The Water well life span generally calculated with water well service practice to prevent the issue of siltation process in formation, with passage of time the silt and sand particles choked the gravel pores for the preventing SDI to come in discharged water. This life span completely relies on water well service practices and rehabilitation by chemical dosing, back washing and water jetting as per condition of well, the better we follow the water well service practices the more tube well serves. Water well services is a part of BNB which provides water well services in maintaining and repairing water pumps and wells.

Lost circulation is potentially one of the most expensive problems in drilling because of the large quantities of drilling fluid that can be lost before losses are cured or reduced to an acceptable level. Lost circulation does not necessarily imply total losses and includes partial or seepage losses. The five tube wells has been drilled to the depth of 800ft for production of 1,000,000 USGPD at shoreline of DHA Phase 8 Karachi to fulfill the requirement of raw water of R.O plant having a capacity of 400,000 USGPD production, the well initially provide the required flow, however the flow has been reduced after 2 years due to negligence to water well service and rehabilitation work in tubewells, resulting in failure and magnificent flow reduction, thereby further three more tubewells have been drilled to complete the required raw water flow for plant production.

Further, the tubewell has been drilled at Site Industrial area Karachi at depth of 800ft, the TDS of well is range between 18,000ppm to 26,000. Primarily it was recommended to physical inspect the pump and piping after each 12 months, however due to negligence towards water well service, the seal and bush of pump has compromised and resulting in high ampere of motor, the operational team enhance the load tripping safety factor on EOCR and continue the pumping which end in motor burned out.

The tubewell has been drilled at Korangi Industrial area, the Omron Dry out sensor relay was installed to prevent the motor to run in dry condition and it was also informed to follow water well service by physical inspect the dry out sensor condition, as with passage of time scaling/salt arose on sensor surface and resulting in false behavior even when it dry out, sensor show water presence due to moisture provided by salt/scaling preserve on sensor surface and resulting in motor burned out.

The well has been drilled at Site Industrial Area, due to negligence towards water well service, they called the contractor when panel starts tripping. Pump was pullout for inspection and found 4 nos impeller housing was malfunction and central shaft was broken.

These all issues and incident can be fortified through proper planning and following the water well service SOP, which could save clients millions of rupees and annoyance of recurrence work as well.

What is Tube well?

A Tube well is a type of water source in which a 100-200 mm tube or steel is inserted into the underground tank. The lower end is equipped with a filter and a pump that collects water for irrigation. The depth required for a well depends on the depth of the water layer.

Volumetric and qualitative Analysis is an imperative phase of well drilling testing. After completion of all drilling activities, logging, casing installation and gravels packing different well water testing conducted for quantification analysis of groundwater. Bore and Bore drilled a water well in reputable multinational Pharmaceutical Company in Korangi Industrial Area. As the crucial requirement of client targeted getting less saline water in huge amount. So, BNB conducted various well water testing to analyze the borehole condition and quantifying the groundwater.

Our client is the second largest pharmaceutical company in Pakistan, BNB is proud to attain this mile stone. To have a water well testing is not only the task for BNB but the provision of safe, healthy and significant groundwater is also the key objective. In order to fulfil these objective BNB start drilling up to 1000ft. water well. After completion of drilling activity BNB performed the geophysical logs (Natural Gamma, Resistivity, SP and SPR) as per requirement of Client. Geophysical logging is very use full well water testing tool to recognition of aquifer zone and lithology of borehole. The logs acquired from boreholes have been used to interpret aquifer zone and the lithologies encountered in the borehole during drilling.

 

BNB moves towards hydraulic and permeability well water testing. Hydraulic well water testing is the air surging method uses compressed air injected in to the well to lift water to the surface. The air in then turned off, allowing the column of aerated water to fall back in to the well, reversing flow back into the aquifer. The cycle of the lifting the water column and then letting it drop by switching of the compressor is vital for the yield testing of aquifers by means of compressor this test provide the 35 USGPM discharge.

 

Furthermore, Permeability well water testing is the measure of the soil’s ability to permit water to flow through its pores or voids. In this well water testing, the water pumped out at constant rate and note down the drawdown of water level with time till the water level become constant. When BNB get desire discharge than well construction activity i.e. casing installation, gravel packing and well development started. During well development further well water testing conducted including compressor washing, well inclination by pump line method, long pump test, step down test and recovery test all these well water testing helps us to interpretation of aquifer modeling. BNB collect water sample for chemical analysis as per client requirement as client need low TDS water so, major physicochemical well water testing parameters analyzed by various standard methods.

 

After all, above mention well water testing, BNB succeeded in the provision of better quality and significant quantity of groundwater to his client. Aquifer analysis of well shows unconfined type of aquifer. Transmissivity ratio in subjected well is also good, due to which relatively good discharge and considerably less draw down observed and BNB able to ensure the good and healthy life of client’s tubewells.

Our client takes pride in being considered as one of the premium and leading names in the Denim Textile and Apparel industry of Pakistan. With a strong global presence and affiliation with top garment industries globally, it takes the spot as the fourth largest Denim processing company of Pakistan and has three huge business units including Textile, Garments and Laundry.

The Textile Unit of the company utilizes state of the art machineries and equipment from prestigious international companies. The allied facilities make its infrastructure one of the most advanced in the Textile Industry of Pakistan. The Reverse Osmosis (RO) Plant is equipped with hi-tech equipment that purifies borehole water used in the plant, while it’s Effluent Treatment Plant (ETP) has the capacity to treat large amount of toxic waste discharging from different areas of the factory. Our client is the pioneer among denim manufacturers with an international standard laundry in Pakistan, with the capacity of 60,000 of garments wash per day. To run these two large business units our client industry requires bulk quantity of water which is fulfilled from KWSB water supplies, recycling of water by ETP/UF and borehole water. Our client had fourteen borehole water wells producing 20,000 to 45,000 USG per day. These borehole water wells vary in depths and range from 500 to 700ft. These wells pump borehole water from Manchar Formation. By the passage of time, borehole water production has depleted due to excessive use of whole INDUSRTIAL AREA OF KORANGI. Borehole water of Manchar Formation recharge from Manchar Lake and rain fall recharge at different exposures of Manchar Formation spread throughout the vicinity of province, the majority of Domestic users of Karachi city is fulfilling need of borehole water from this formation and big chunk of industry as well. Borehole water quantity of this formation is now reducing with time as the extraction is much greater than the recharge.

So, BNB investigated the whole scenario through electrical resistivity survey and suggested an alternate way to decrease this borehole water crisis by drilling a new borehole up to 1200ft into relatively un-utilized aquifer of Jhill limestone. This Jhill formation comprises of limestone and shale, alternate layering of confined aquifers under the sealed layer of Drig clay, both are the member of Gaj Formation. Due to the natural sealed of Drig Clay, its prevent the subsidence phenomena cause due to extreme extraction of borehole water from upper aquifers. Although the cost is relevantly too high, however our client decided to spend more money to SAFE the future of KARACHI and set an example for other INDUSTRIES as well. Currently, tubewell of our client producing 178,000 USG per day borehole water, which fulfilling his borehole water production need without vulnerable the city structures.

Our client has strong market presence in nearly all pharmaceutical segments. For 50 years it has been offering high quality affordable pharmaceutical products and services to improve the overall health standards and making healthcare available to everyone. In order to produce best quality medicine and increase production they required significant amount of water. Water being the essence of industrial sustenance, holds critical value. To fulfill their requirement, they negotiated with Bore and Bore (Leading service providers with substantial expertise in water drilling and underground water estimation).

Bore and Bore started water drilling with his client in November of 2017 and was finalized in February 2018. After reconnaissance geological survey, BNB conducted detailed electrical resistivity survey to mark the low TDS and highly productive aquifer which provided subsurface stratigraphic column i.e. Korangi Conglomerate, Manchar Sandstone, Drig Clay, Talawa Limestone, hill Limestone and Metan Clay respectively.  In Jan, 2018 BNB started water drilling test borehole after completion of water drilling activity BNB performed geophysical logging to obtain lithological data and assign aquifer horizon. As per technical discussions with client, the key requirement was to obtain Low salinity water, but Korangi Industrial area which is the main hub of industries in Karachi has mostly zones of high TDS varying with depth. In Korangi Industrial Area there are more than 100 nos. of water drilling done as of now drilled till varying depths of 200 ft. to 1000 ft. producing water from Manchar Formation which is draining due to excessive pumping. During this project BNB introduced the recently discovered advance water drilling technique which is Aquifer Horizon Segregation (AHS). In order to fulfil industrial requirement BNB proposed to drill water drilling till 1200ft. to attain the Jhill Limestone of Gaj Formation that can produce significant amount of water and seal the upper aquifers to obtain less saline ground water.

Then onwards, BNB made it standard practice to drill deep water drilling in industrial zones like Korangi Industrial Park, SITE area, Karachi Export Zone etc. with the help of advance techniques (AHS) we can save deep aquifer’s from infecting it from upper contaminated water.

Currently, our client has commissioned the deep-water drilling which was constructed on state-of-the-art method of AHS and after this water drilling, our client successfully replenishing its need of daily water production.