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From being the preserve of the rich and the famous to an amenity used by themiddle class, swimming pools have come a long way in India. From hotels, they’venow come home. Most residential schemes these days boast of an in-house gymand pool – criteria seen as essential for the good life.

Pools are more than just a hole in the ground and plenty of water. Over the years,construction technology has changed rapidly, and today pool design may involveknowledge of art, landscape, engineering and technology.

It’s clear that things are going swimmingly for pools. Ar. Roopa Sabnis Pingetakes an in-depth look at the evolution of swimming pools, their growing popularityin architectural projects and modern pool construction technology.

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The Great Bath at the siteof Mohenjo-Daro was most likely dugduring 3rd millennium BC. This poolis 12 by 7 metres, is lined with bricksand covered with a tar-based sealant.Ancient Greeks and Romans builtartificial pools for athletic training,for nautical games and for militaryexercises. Roman emperors hadprivate swimming pools in which fishwere also kept (hence one of theLatin words for a pool, piscina). GaiusMaecenas (one of the first knownpatrons of arts) of Rome built thefirst heated swimming pool in firstcentury BC. Ancient Sinhalese builtpairs of pools called Kuttam Pokunain the kingdom of Anuradhapura, Sri

Lanka, in 4th century BC. Thesewere decorated with fl ights ofsteps, punkalas, or pots ofabundance, and scroll design.

There is a mention of a swimming pooleven in the Ramayana! Ayodhya,Kiskindha and Lanka, the three citiesrelated to this period, were centresof many games and sports. Swimmingwas popular and it is learnt thatRavana had a beautiful swimming poolin Asoka Vatika. In the Mahabharatatoo, people have been shownenjoying water sports. Bhima andDuryodhana were great swimmers. Allthe Pandava and Kaurava princes, on

the invitation of Duryodhana, are alsoknown to have gone to the Gangesfor water games.

Swimming pools became popular inBritain in the mid-19th century. By1837, six indoor pools with divingboards were built in London. Theoldest surviving swimming club in theworld is believed to be the ArlingtonBaths Club in Glasgow, Scotland. TheArlington was founded in 1870 and isstill an active club operating out ofits original Victorian building with a21m pool.

The popularity of swimming poolsbegan to spread after the

modern Olympic Games began in 1896and included swimming races. In 1839,Oxford had its first major publicindoor pool at Temple Cowley, andswimming began to take off. Today,swimming is a highly popular sport andhobby the world over. The inclusionof swimming pools in housing schemesis probably one of the mostsignificant factors in the history ofresidential architecture in India. Itreflected a change in lifestyle, andin turn, ushered in more change!

Ar. Rachana Amin, a very seniorassociate at the studio of HafeezContractor, believes that swimmingpools have today become a necessity,rather than a luxury. Any scheme sellsbetter when better amenities areprovided by the architect — andswimming pools top the list. Manyhigh-end residential schemes also usegyms and sports facilities as the USPof the project as the contemporarylifestyle often does not allow enoughtime to go out and exercise. So a gym,with a swimming pool, in theclubhouse of your own residentialsociety makes perfect sense!

About Swimming Pools

What is a swimming pool? Simply put,a swimming pool is a container filledwith water intended for swimming orwater-based recreation. There aremany standard sizes — the largest anddeepest is the Olympic-size swimmingpool. A pool can be built eitherabove or in the ground, and withmaterials such as metal, plastic,fibreglass or concrete.

Pools that may be used by many orby the general public arecategorised as public pools; poolsused exclusively by a few people orin a home are called private pools.Many health clubs, fitness centresand private clubs have public poolsused mostly for exercise.Hotels and holiday resorts havepublic pools for relaxation. Hottubs and spas are pools with hotwater, used for relaxation ortherapy, and are common in homes,hotels, clubs and massage parlours.Swimming pools are also usedfor diving and other water sports, aswell as for training of lifeguards andastronauts.

Chemical disinfectants suchas chlorine, bromine or mineralsanitisers, and additional filters areoften used in swimming pools toprevent growth and spreadof bacteria, viruses, algae and insectlarvae. Alternatively, pools can bemade without chemical disinfectantsby using a bio-filter with additionalcarbon filters and UV disinfection. Inboth cases, pools need to have anadequate flow rate.

Public or private, the constructionof a pool is a highly challenging job,and requires a good knowledge of thetechnicalities involved. So though anarchitect may design a beautiful pool,it is up to the swimming poolconstruction specialist to execute itwell, and provide users with arelatively maintenance-free amenityfor recreation or exercise. OceanicPool Construction, in Mumbai, is oneof the well-known swimming poolspecialists who regularly work witharchitects like Hafeez Contractor.Whether it’s the pool for Seawoods,a residential scheme in Navi Mumbai,or for Hotel Hyatt Regency, near theinternational airport in Mumbai,in

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Oceanic has executed some beautiful pools forContractor. Ar. Rachana Amin, who was the architect incharge of both projects, is quite satisfied with the qualityand service delivered by Oceanic.

Bangalore-based Millennium Pools is also engaged inconstruction of swimming pools, water bodies and spasacross India for the last 20 years. The firm takes up thecomplete job - from excavation to commissioning - onturnkey basis under the supervision of experiencedengineers. Millennium specialises in using gunitingtechnology for constructing pools — a technology theyhave perfected along with AquaPlan, their associates inSwitzerland. The process, called M-Crete, based on theshotcrete system (guniting or spraying concrete at highpressure), gives a one-piece shell, with smooth, roundededges. This highly compacted monolithic shell is 100 percent waterproof, and therefore better than the pouredconcrete method usually used by local contractors.

Length

Most pools in the world are measured in metres, with ashort-course pool (25m) or a long-course one (50m) beingthe standard lengths. There also exist many pools 33mlong, so that 3 lengths amount to 100 m. This pooldimension is commonly used to accommodate water polo.The international standard is metres, and world recordsare only recognised when swum in 50m pools (or 25m forshort course). In general, the shorter the pool, the fasterthe time for the same distance, since the swimmer gainsspeed from pushing off the wall after each turn at theend of the pool.

Width

Most pools are between 10m and 50m wide.

Depth

The depth of a swimming pool depends on the purposeof the pool, and whether it is open to the public orstrictly for private use. If it is a private casual, relaxingpool, it may go from 1 to 2 m (3.3 to 6.6 ft) deep. If it isa public pool designed for diving, it may slope from 3.0to 5.5m (9.8 to 18 ft) at the deep end. A children’s playpool may be from 0.3 to 1.2m (1.0 to 4 ft) deep. Mostpublic pools have differing depths to accommodatedifferent swimmer requirements. In many jurisdictions,

There was a time when people would animatedlytalk about a certain building and the residents wouldboast of their address – because of a swimmingpool in the premises. Similarly two decades ago,people chose to stay in a five-star hotel since oneof its attributes was a swimming pool.

Today every residential project, small or large, isplanned with one, or more, swimming pools. Withspace being a constraint in smaller buildings, poolsare located on the terrace. In their brief to architects,developers inc lude the provision of one, and incase of larger residential projects, even up to threepools! Similar ly, it is no longer only five-star hotelsthat are designed with swimming pools. Almostevery hotel from two-star level upwards boasts ofa pool. In fact, swimming pools have now becomean essential part of every development -residential, hospitality, and even office orinstitutional.

Swimming pool designs have also evolved. Fromthe simple rectangle, shallow on one side anddeeper on the other, swimming pools are now seenin all shapes and sizes, made conventionally in RCCwith tiling, or in membranes, or in fibreglass withnumerous additions to it.

There are buildings being designed where eachapartment has its own little private pool on a terrace,and there are hotels, which may have a largelagoon pool in addition to individual pools, attachedto the larger suites.

Infinity pools, which first originated from the ideaof an elevated pool without a visible edge seenagainst the backdrop of an ocean, have nowbecome almost mandatory – irrespective of thebackdrop! In holiday resorts, large lagoon pools(covering an area of 1 to 3 acres) are designed toflow gracefully around the property. These arefur ther elaborated by the inclusion of open-airJacuzzis and multi-level pool areas with slides orwaterfalls between them. Many resorts also providewater-sports as an additional attraction in theirfacilities.

Water may be becoming a scarcity, but it seemsswimming pools are here to stay!

- Ar. Sanjay Puri

FromExclusivity

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it is a requirement to show the waterdepth with clearly marked depthsaffixed to the pool walls.

Types of Pools

Private Pools: Private pools are usuallysmaller than public pools, on average12 × 24 ft (3.7 × 7.3m) to 20 × 40 ft(6.1 × 12m), whereas public poolsusually start at 80 ft (24m). Homepools can be permanently built-in, orbe assembled above ground anddisassembled after summer.

Public Pools: Public pools are oftenfound as part of a larger leisure centreor recreational complex. Thesecentres often have more than onepool, such as an indoor heated pool,an outdoor saltwater or unheatedchlorinated pool, a shallowerchildren’s pool, and a paddling poolfor toddlers and infants. There mayalso be a sauna and one or more hottubs or spa pools (Jacuzzis).

If a pool is in a separate building, thebuilding is called a natatorium. Thebuilding sometimes also has facilitiesfor related activities, such as a divingtank. Outdoor pools are common inwarmer climates. Larger poolssometimes have a diving board affixedat one edge above the water. Divingpools should be deep enough so thatdivers are not injured.

Many public swimming poolsare rectangles 25m or 50m long, buta pool may be any size and shapedesired. There are also elaboratepools with artificial water falls,fountains, splash pads, wavemachines, varying depths of water,bridges, and island bars.

Hot Tubs and Spa Pools: Hottubs and spa pools are commonheated pools used for relaxation andsometimes for therapy. Commercialspas are common in the swimmingpool area or sauna area of a healthclub or fitness centre, in clubs,motels and exclusive five-starhotel suites. Commercial spas aregenerally made of concrete, witha mosaic-tiled interior.

Whirlpool tubs first became popularin the United States during the 1960sand 70s. A spa is also called a Jacuzzithere since the word becamegeneric after plumbing componentmanufacturer Jacuzzi introduced theSpa Whirlpool in 1968. Air bubbles maybe introduced into the nozzles via anin

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Pools have been present in ancient India. Tracesof a pool can be found in Jahaz Mahal, Mandu,and other palaces and royal residences, butnot beyond that - not in the common man’s life.Those pools were less likely meant formaintaining fitness and more for leisure.

Indeed, water is a refreshing and de-stressingelement of nature and a swim certainly can bea great stress-buster! However, this is a Westernthought, not applicable necessarily to the Indianmindset. We, as Indians or as individuals fromdeveloping or third-world nations, believe inmimicking Western values without justifying thepurpose - just as we jumped to glass structuresand now, after burning our fingers, are stillscared to return to our roots.

Unfortunately therefore in India, a pool hasbecome synonymous with the elite or higherclasses as their attempt to showcase theiraffluence and Western style of living. Whetherin private homes or high-end residentialcomplexes and gated community spaces, thetrend today is to have a swimming pool as anamenity! But is the pool ever used? Or is itmerely a status symbol? The answers to boththese questions are obvious.

In Europe and America, pools suit the lifestyleof the people. Weather conditions also supportthem. In dusty Indian conditions, poor attitudetowards physical exercise, conservative socialstructuring and cultural barriers are a few veryimportant issues we have to address beforeblinding aping the West, or imbibing their statussymbols! To some extent, individual familydynamics and metropolitan views will have animpact on the way Indians can use the swimmingpool – but by and large, we, as a people, arestill not very comfortable around them.

In the hospitality sector, however, a swimmingpool is a mandatory addition to the design brief.It can offer the guests an easy way to unwindand relax, after a hard day’s work.

- Ar. Rahul Dalvi

Evolutionof the

Pool Culturein India

air-bleed venturi pump that combines cooler air with theincoming heated water to cool the pool if the temperaturerises uncomfortably. Some spas have a constant streamof bubbles fed via the seating area of the pool, or a foot-well area. This is more common as a temperature controldevice where the heated water comes from a natural(uncontrolled heat) geothermal source, rather thanartificially heated. Water temperature is usually very warmto hot — 38 to 42 °C (100 to 108 °F), so bathers usuallystay in for only 20 to 30 minutes. Bromine or mineralsanitisers are often recommended as sanitisers for spasbecause chlorine dissipates at a high temperature,thereby heightening its strong chemical smell. Ozone isan effective bactericide and is commonly included inthe circulation system with cartridge filtration, but notwith sand media filtration due to clogging problems withturbid body fats.

Ocean pools: In the early 20th century, especiallyin Australia, ocean pools were built typically on headlandsby enclosing part of the rock shelf, with water circulatedthrough the pools by flooding from tidal tanks or byregular flooding over the side of the pools at high tide.This continued a pre-European tradition of bathing inrock pools, or bogey holes, with many of the currentsites being expanded from sites used by AustralianAborigines.

Infinity pools: An infinity edge pool (also named negativeedge or vanishing edge pool) is a swimming pool thatproduces a visual effect of water extending to the horizon,vanishing, or extending to infinity. Often, the water appearsto fall into an ocean, lake, bay, or other similar body ofwater. The illusion is most effective where there is asignificant change in elevation, though having a naturalbody of water on the horizon is not a limiting factor.

Zero-entry swimming pools: A zero-entry swimming pool,also called a beach entry swimming pool, is a swimmingpool having an edge or entry that gradually slopes fromthe deck into the water, becoming deeper with eachstep, in the manner of a natural beach. As there are no

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stairs or ladders to navigate, thisgradual entry assists older people,young children and peoplewith accessibility problems.

Types of Pool Construction

The main difference betweendifferent types of pools is how thebasin is constructed. There areseveral different pool styles, eachwith its advantages and disadvantages.

Above-ground pools are thecheapest construction option as wellas the easiest to build. Most above-ground pools are made fromprefabricated kits, which even anamateur can put together (thoughmost people go with professionalinstallers). First, the installers leveloff the ground to form a flat buildingsurface. Then they assemble aperimeter track, which supports theouter wall (made of metal, plastic orwood). Next, they spread sand in thepool area and lay the plumbing.Finally, they secure the vinyl linerover the pool walls, fill the pool withwater, smooth the liner and fasten itinto place. As soon as they hook upthe pump and filtering system, thepool is ready to go. The maindisadvantage of this sort of pool isthat it is less durable than otherdesigns, and generally less attractive.It’s also less permanent, which canbe a good thing - it’s relatively easyto disassemble the pool and move itto a new location.

Fibreglass pools are made fromfibreglass-reinforced plastic, whichhas been moulded into a basin shape.To install the pool, a constructioncrew digs an appropriately sizedhole, lays the necessary plumbing,adds some sand filler, and lowers thepreformed pool structure into thehole. Then they level the pool, hookup all the plumbing and backfill in thearea around the pool. The pool isusually surrounded by a concretedeck structure.

Vinyl-lined in-ground pools are a lotlike above-ground pools,structurally, but they look more likeconventional in-ground designs. Theconstruction crew digs a hole andassembles a metal, plastic or woodframe wall around the hole’sperimeter. As in an above-groundpool, the crew lays sand along thebottom of the hole and secures thevinyl lining to the structural wall.These pools are a lot cheaper thanin

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Swimming pools and their use has changedconsiderably over the past decade or so. Inmetropolises, especially, the trend to have swimmingpools in all residential developments is no longerjust for marketing the project. People have becomemore health conscious, and use swimming forexercise as well as recreation. In recent andupcoming developments, the facility of a clubhousewith a decent-sized pool has become common – anecessary amenity rather than jargon.

However, we are also aware of typical Indianmentality, and therefore in smaller towns, and evenin certain conservative localities in the metros,swimming pools may not be used as much. In privatehomes also, swimming pools are an upward trend.There are also more modern innovations like havinga pool and Jacuzzi combo. About 20’ long, it seemslike a nice product! Home pools, spas andwhirlpools also offer privacy. In the hospitalitysector, swimming pools are of course well used. Butin smaller Indian hotel brands, largely, one adds aswimming pool to the brief as it is a mandatoryelement in the star -classification guidelines. Sosometimes, even a small pool is made, whichotherwise may not be sufficient for proper exerciseor recreation. And since it is indeed not even usedvery much, a small pool can be justified.

In terms of technology too, there are greener, saferoptions for keeping the pool clean. These optionsare preferred over chlorination as they are supposedto keep the water fresher for a longer time.

- Ar. Khozema Chitalwala

‘Poolsare a

Necessary AmenityThese Days’other in-ground designs, but not as durable. Typically,

the liner needs to be replaced every 10 years or so.

Gunite pools are the most popular design in much of theUnited States. To build one of these pools, theconstruction crew digs a hole, puts the plumbing in placeand assembles a framework grid with 3/8-inch steelreinforcing rods (rebar). The rebar rods are spaced about10 inches apart, and secured together with wire. Whenthe grid is in place, the crew sprays a heavy coating ofgunite, a mixture of cement and sand, around the rebar.The sprayer unit combines dry gunite mix with waterjust before spraying — this produces the wet concretematerial. The crew trowels the gunite smooth and lets itsit for a week or so before applying a smooth finish tothe rough surface. The most popular finish is calledplaster (actually a mixture of cement and marble sand),but a lot of people finish their pools with special concretepaint. Gunite pools can also have tile, exposed aggregateor even fibreglass finishes. Gunite pools (and theircousins, shotcrete pools) are highly durable and can bebuilt in any shape or size.

Poured-concrete pools are similar to gunite pools, butthey’re a lot harder to build. Instead of spraying concretematerial around a rebar framework, concrete is actuallypoured into conventional wooden forms. With the riseof gunite methods, poured-concrete construction hasbecome less popular. In masonry block pools, the wallsare constructed with concrete blocks.

While these pool designs are quite different, they allrely on the same basic plumbing and filtering systems.

What is Gunite?

Gunite concrete is a new innovation that has re-definedpool design and construction all over the world. Here’swhat makes gunite concrete a watertight concept. Guniteconcrete is a rich cement-aggregate mix, with low-watercontent. The compaction strengths achieved by thisprocess make pool walls rock-hard and impermeable.

There is more to gunite concrete than the mix. Theprocess uses compressed air-driven guniting guns thatshoot the mix on to steel reinforced walls, under highpressure. Here is where expertise becomes the key input,to ensure a spraying technique that’s precisely regulated.The steel-reinforced structure can be easily erectedalong pool contours, which adds to the flexibility ofworking with free-flowing shapes and forms. The lagoonlook is extremely popular these days.

Once the gunite concrete sets and hardens, it providesa perfect surface for the finishing touch — with designertiles that can be patterned around graphics, motifs,personal logos and existing visual concepts.

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• As the name implies, shotcrete isconcrete placed by “Shooting”.“Shooting” is done by means of agun, so shotcrete is also calledGunite concrete.

• A pneumatic compressor of about450 cfm prepares a thorough mixof cement, aggregate and sand.This integrated dry mix ispneumatically conveyed througha delivery hose to a nozzle, whereadequate water is added.

• Provided the water-cement ratioand the mix is same, theproperties of shotcrete are thesame as those of traditionalconcrete in respect ofcompressive, tensile and shearstrengths. But there is onenotable difference. Sinceconcrete is placed by shootingwith a tremendous force, it isextremely compact and therebyimpermeable to water.

• In fact, many existing hydraulicstructures and under groundcavities are sealed by the use of

shotcrete and thus made leak-proof.

• Another aspect distinguishingshotcrete from ordinary concreteis its ability to adhere to anysurface, whatever the angle ofinclination. Since it is applied inlayers, it is well compactedimmediately on placement andcompaction and the latter stagei.e., compaction can sometimesbe faulty subject to human andmechanical error.

• Pool shell formed by shotcrete ismonolithic in nature with nojoints; whereas in conventionalpoured concrete, there areconstruction joints, which aremost vulnerable to leakage over aperiod of time.

• To prepare good concretethorough mixing of cement andaggregates is very important andthis extremely well done inshotcrete by means of pneumaticpressure.

• We earlier said that theproperties of concrete andshotcrete are same, providedwater cement ratio is same. Butabout 20 per cent less water isused in shotcrete – sinceworkability is not a criterion andwith a lesser water-cement ratio,shotcrete has higher compressivetensile and shear strengths.

• No formwork (shuttering) isrequired and this has a time/costsaving consequence. Free-formpools are particularly possible ina cost effective way, becauseinstalling formwork of a free formpool with various curves andslopes is tedious and expensive.

• Shotcrete is a continuousoperation and thus the completionof a pool is accomplished in ashorter time vis-à-vis conventionalconcrete method.

Footnote• The technical information about Gunite-

Shotcrete Pools has been provided byMillennium Pools.

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