The open-air swimming pool at Luton, which is described below, was opened by the deputy mayor of the municipal corporation (Ald. G. Wistow Walker, J.P.) on July 27. The swimming pool, 165 ft. by 90 ft., is rectangular in shape, and has depths of water from 2 ft. 6 in. at the two shallow ends to 8 ft. at the centre, with a section opposite the diving stage of a depth of 10 ft.
| Name | Luton Open Air Pool aka Wardown Swimming Centre |
| Built | 1935 |
| Opened | 27th July 1935 by Mayor Ald. G. Wistow Walker, J.P |
| Cost | £28,000 |
| Dimensions | 165′ x 90′ |
| Capacity | 448,000 gallons (including paddling pool) |
| Max depth | 2′ 6″ at each end to 8′ in centre |
| Diving | 10′ diving pit |
| Second pool | Paddling pool 50′ x 25′ |
| Designer | Mr. J. W. Tomlinson, Assoc.M.Inst.C.E., L.R.I.B.A., the engineer and surveyor to the Luton Municipal Corporation |
| Address | 1 Bath Road, Luton, Bedfordshsire, LU3 1ES |
| Date closed | 1990’s |
| Status | Demolished |
| Notes | |
| Links |
Feature article following opening
The open-air swimming pool at Luton, which is described below, was opened by the deputy mayor of the municipal corporation (Ald. G. Wistow Walker, J.P.) on July 27.
The swimming pool, 165 ft. by 90 ft., is rectangular in shape, and has depths of water from 2 ft. 6 in. at the two shallow ends to 8 ft. at the centre, with a section opposite the diving stage of a depth of 10 ft.
The diving unit consists of five boards, three being rigid and two being springboards and the highest board is 17 ft. 3 in. above the water. The unit is designed in accordance with the requirements of the Amateur Diving Association and is suitable for competition purposes.
There are also two water chutes, one 10ft. high and the other 6 ft. high. At the south end of the pool a paddling pool 50 ft. by 25 ft. has been provided for the use of children.
The swimming pool is constructed of reinforced concrete throughout, the sides being lined with specially made polished slabs and provided with combined scum trough and hand rail in similar material.
Around the pool is a paved area 20 ft. wide and raised terraces also 20 ft. wide are provided on either side for the use of spectators. The dressing accommodation is situated down either side of the enclosure. It is conveniently arranged in sections so that any particular section may be closed off from another section if desired. Dressing cubicles are provided on either side of the pool and for each cubicle three lockers are provided which enables a total number of 1,200 bathers to use the pool at the same time. Each section of the dressing accommodation is provided with shower bath, foot spray and sanitary accommodation.
While the bather is using the pool, clothing is left in one of the lockers which, once being closed, can only be opened by the attendant. All lockers are numbered and the bather is furnished with a disc or wristlet having a corresponding number or colour.
Purification Plant.
The combined contents of the large swimming pool and the children’s pool, totalling 448,000 gal., are circulated and continuously purified in six hours at the rate of 75,000 gal. per hour.
The water is drawn from the deepest point of each bath and run into a common suction main by which it is conveyed to the filter house . The suction piping just before the circulating water pump is fitted with a strainer box having a basket strainer through which the water passes, and the coarse suspended solids such as hairs, lint, stones, etc. , are retained in the basket. The strainer box is fitted with a quick release cover which can be secured or released by two turns of a central hand wheel.
The water is circulated through the purification plant by a low lift centrifugal pump driven by means of a 17 h. p. electric motor.
Immediately on leaving the pump the water is treated with a coagulant in the form of sulphate of alumina and an alkali in the form of soda to rectify the pH of the water. These reagents are continuously and proportionately administered by a Paterson venturi controlled reagent proportioning apparatus. A quantity of alumina is placed in a pressure container and a quantity of soda in another similar container, and these are connected by piping to the inlet and throat of a venturi tube. The differential head between the two points of the venturi tube ensures that a proportion of the main flow of water will pass from the inlet through the containers and return to the main flow of water at the throat of the tube. The water in its passage through the containers is formed into a saturated solution of the reagent and is, therefore, always of constant strength. The quantity of water by-passed is always proportional to the rate of flow of water through the venturi tube. Fitted on the water piping between the inlet of the venturi tube and the containers are direct reading reagent flow indicators which show the actual amount of chemical reagent being administered at a particular time – further, a direct reading mercury column water flow indicator is also provided. The two reagent and one water flow indicators are fitted on a panel placed adjacent to the reagent containers. The provision of direct reading indicators showing the rate of flow of chemicals and water enable the attendant to accurately adjust the rate of dosing when required. This type of apparatus, when provided with these indicators, is an exceedingly accurate method of administering the coagulants. The reagent containers and other components are constructed of suitable materials to withstand the action of the acid and alkali.
After treatment the water is delivered to two 8 ft. diameter by 18 ft. long Paterson horizontal pressure filters and is distributed uniformly along each filter by a trough, and then flows downwards through a bed of Leighton Buzzard sand, resting on an underbed of graded pebbles. The filtrate is collected on the underside of the filtering medium by the Paterson manifold under-drain system which is constructed of noncorrodible materials, and is designed in such a manner that it will not become choked. This under-drain collecting system consists of a series of perforated laterals covering the filter floor and connected to a central collecting header by tee pieces of special design.
At intervals the filters require cleansing of the accumulation of intercepted impurities. The operation of cleansing is entirely mechanical and consists of opening and closing certain valves in rotation. The filter is first taken out of pressure and the water level lowered to the lip of the internal trough. Compressed air provided by an electrically driven rotary blower is delivered into the under-drain system by which it is evenly distributed throughout the entire mass of the filter. The air is discharged from the orifices fitted on the underside of the lateral tubes, is spread by impinging on the flat bottom of the filter, and further diffused as it passes upwards through the coarse pebbles of the underbed. The diffused air rises up through the sand, agitating it and loosening the intercepted impurities. The air scour is applied for about 1 min. The loosened impurities are floated to drain by an upward flow of water which again is introduced and distributed by the under-drain system. The dirty water is discharged into the waste water collecting trough from which it is piped to drain. The wash water is applied for about 3 to 4 min. for each filter wash.
The water is aerated and re-oxygenated by flowing over cascade fountains which form an architectural feature of the pool. Sterilisation is by chloramine formed by administration of ammonium sulphate and chlorine gas to the water. The ammonium sulphate is measured by a venturi controlled proportioning apparatus, and applied before aeration. The chlorine gas is applied to the water as it leaves the basin of the cascade fountain by a Paterson Bath Chloronome. The advantage of sterilising the water by chloramine is that the effect of sterilisation persists the whole of the time the water is in the bath, thus there is always sufficient sterilising reagent present in the water to render innocuous any pathogenic organisms introduced by bathers. This very excellent result is a definite safeguard to the health of the bathers and is obtained without the use of excessive doses of chlorine, without smell and discomfort to bathers.
The water, after passing over the cascade fountains, is conveyed by piping to the shallow end of each pool, where it is distributed by a number of inlets.
The water is tested at frequent intervals for alkalinity and the presence of free chlorine by means of a Paterson Chloroscope, which is provided with fadeless glass colour standards for purposes of comparison. The tests are simple and can be accurately performed by anyone of average intelligence without chemical knowledge or training.
The floor of the bath is kept free of deposit by a Paterson trolley type suction sweeper. The deposit is drawn from the floor by a suction nozzle having an internal spring loaded brush, which will loosen any matter off the floor to enable it to be withdrawn through the nozzle. Special care has been taken in the design of this nozzle to accelerate the speed of sweeping, the nozzle being so shaped that a high velocity of flow is secured with the minimum loss of head; thus the rate of travel of the sweeper across the floor of the bath is appreciably increased, reducing the time required for the operation of sweeping. The nozzle is carried by rubber-tyred wheels which are adjustable, permitting the nozzle to be raised or lowered to suit the type of deposit to be removed. The nozzle is connected to an electrically driven pump mounted on a trolley fitted with rubber-tyred wheels for moving into any position along the bath walkway. The suction hose is of super-flexible smooth-bore pattern, reducing the drag on the nozzle and giving flexibility of movement, which is further increased by the use of a swivel pattern coupling on the nozzle. Pneumatic floats are used for carrying the suction hose, these being an improvement on the cork and tin floats usually employed. The suction nozzle can be moved over the floor of the bath by guiding ropes or rods. The whole installation employs the latest methods of water purification and is similar in design and construction to the equipment provided by this company for the purification of drinking water supplies.
The Paterson Engineering Co. were the first water purification engineers in Great Britain to apply chloramine treatment in this country to swimming bath water, and the successful results obtained from this installation has led to the general adoption of the treatment in this country. The Paterson method of applying chloramine is based on well-known and established principles which cannot be covered by a master patent.
General.
The administrative buildings are at the south end of the site and consist of a cafe in the central position 34 ft. by 24 ft. with the necessary service rooms. The block also contains superintendent’s office, ticket office, chair and towel stores, ladies’ and gentlemen’s conveniences and attendants’ room, while the filtration plant is housed in an extension of the main building on the east side.
The roof of this building is flat and has been constructed so as to form a spectators’ balcony overlooking the swimming pool and its surroundings. The roof is extended forward to provide an open-air additional area in connection with the cafe and shelter for visitors in stormy weather.
A loudspeaker equipment has been installed so that any announcement can be heard clearly all over the pool and so that music may be provided at any time.
A large car park has been provided with accommodation for some 200 cars.
The total estimated cost of the scheme is approximately £28,000.
The pool was designed by Mr. J. W. Tomlinson, Assoc.M.Inst.C.E., L.R.I.B.A., the engineer and surveyor to the Luton Municipal Corporation.
Mr. A. A. Tarbox, N.A.B.S., R.L.S.S., Dip. A.H.A.S.A., is the general superintendent and engineer of Luton’s public baths.
Contractors and Sub-Contractors.
The following contractors and sub-contractors have carried out the work: General contractors, E. D. Winn and Co., Ltd. ; piling work, John Gill and Co., Ltd. ; filtration plant, Paterson Engineering Co., Ltd.; cascades, F. Bradford and Co., Ltd. ; diving stage equipment, Spencer, Heath and George, Ltd.; sanitary fittings, Shanks and Co., Ltd.; electric installation, A. T. Snowden; ironmongery, Gibbs and Dandy, Ltd.; wireless and loudspeakers, Masterphone Electric Co. ; terrazzo slabs, Johnston Bros. ; lockers, Milner Safe Co., Ltd. ; asbestos slating, Turners Asbestos Co., Ltd.; ornamental ironwork, Parker, Winder and Achurch.
Baths and Baths Engineering, September 1935
