1. General
Introduction
purpose the rainwater may also be used for flushing toilets, washing clothes or cleaning purposes. In that case the rainwater is stored in a tank which must be provided with an overflow. Before proceeding to investigate the principles of drainage it will be as well to determine the nature and quantity of the drainage requirements.
charges of varying kinds, temperatures, quantities, frequencies and so on. On health, hygiene and odour control consi- derations the system is sealed with traps or siphons. When discharges take place, air in the system has to make way (ven- ted) for waste water. The principal problems of drainage are as follows: intermittent drainage, enclosed open system, complete removal of soil and water is required. Excess rainwater is also led away to the external sewer, nowadays generally to a separate storm drain. If the water is relatively clean it may be led from the storm drain to balancing ponds or waterways. Alternatively, clean rainwater may also be discharged onto the land around the property or into a collective facility. Where the roof is suitable for the
Water is supplied by means of enclosed pipework systems using internal pres- sure. Waste water is generated when the supplied water is used for cleaning, was- hing, cooking and for flushing away human waste. In discussing waste water a distinction is made between black water (from toilets) and grey water (from washing machines, showers and similar). The black water presents a direct hazard to health, grey water does not. Black and grey water are generally discharged together into the above-ground drainage system which carries the water to the underground private sewer (U-drain) into the public sewer or local treatment facility (septic tank). The above-ground drainage system is an open system which is accessible at several locations for dis- The system is manufactured to EN 1519 specifications which incorporate a test temperature of 110 o C.
Wavin HDPE Product & Technical Guide
Wavin
This technical manual on HDPE above-ground drainage systems deals with the removal of domestic waste water and rainwater from houses and residential and commercial properties using plastic piping systems. It covers all aspects from design to installation. The manual is intended for clients, architects, construction specialists, building co-operatives, building inspectors and of course for installers. If you have any questions, wishes or practical problems not covered by this manual then we would ask you to submit them to us together with any suggestions for amendments and additions. Since our systems are often utilised in circumstances beyond our control, we cannot accept liability for the consequences of applying the information provided in this manual.
The Wavin group of companies is one ofthe largest manufactur- ers of complete plastic pipe systems for the Building, Civil and Utility markets in Europe. In addition to having its own produc- tion facilities in almost every country on the European continent, Wavin also participates in the equity of plastic pipe companies in Australia, New Zealand and Singapore. In the remainder of the world the company is proud of an ever increasing impressive network of licensees, distributors and agents. Wavin has manufac- tured and supplied plastic pipe systems since 1955.The strength of the Wavin Group in terms of manufacturing capability and technical resources places the company at the forefront of the industry for product quality, innovation, technical support and customer service. A survey carried out by international consultants for European Plastic News, a leading trade journal, identified Wavin as the foremost contributor in the development of plastic pipe systems and the leader in the field of marketing and technology.
1.1 Quantities
Domestic waste water The quantities of water consumed and requiring removal vary appreciably throughout the day and depending on the source of the discharge. 120 to 130 litres per person per day are used as the basis of calculations for supplies required for domestic use. The assumption is that the water used will be led off at the rate of 10 to 12 litres per person per hour. Illustration 1.1 shows the discharge pat- tern for a 3 to 4 person household over 24 hours. Basic discharge rates (Q¡) to determine the required capacity for a given section of pipework are included in NEN 3215 (see illustration 1.2). Illustration 1.2 also shows the required diameters for the trap and for the pipe connecting to the source of the discharge. The quantity of waste water in collecting pipe stacks, that is, those containing discharges from several fittings, can be determined by means of the formula: Q o = p Σ Q ¡ , where Q o and Q ¡ are in l/s. Σ Q ¡ is the sum of the baseline discharge rates to be removed by a collecting pipe. p is a coefficient for simultaneity: - houses and residential properties p = 0,5 - schools, offices, hotels, restaurants, hospitals p = 0,7 - laboratories, sustained industrial discharges p = 1,2 - commercial kitchens p = 1,4
Wavin Overseas
Wavin Overseas B.V., situated in The Netherlands, is the central export organisation of the Wavin Group dedicated to providing a global service. HDPE Fittings are Manufactured in Italy. Wavin Overseas sells Wavin products, supplies technology (under licence) and equipment to manufacture these products locally. Wavin Overseas is experienced in setting up complete factories, delivering a comprehensive package of manufac turing equipment, ancillaries and services such as production know-how and technical support. In effect Wavin Overseas can supply all the help you need to supply your market. Wavin Overseas operates under a Quality Management System, which is accredited to EN ISO 9001:2000 by the Dutch Council for Accreditation.
A Wide Range of Products
Wavin’s extensive range of plastic pipe systems is designed and manufactured to meet the highest standards set by the building and construction industry worldwide. Wavin’s products are generally available ex-stock from one of our numerous distri-bu- tors around the world.
Bath/shower
41 l/pp.day 33 l/pp.day 20 l/pp.day 17 l/pp.day 9 l/pp.day 120 l/pp.day
Illus. 1.1 Mean water consumption for an average household over 24 hours.
Toilet
Washing machine
Sink
Various
6
7
Total
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