18-01-2013, 02:41 PM
DESIGN OF WATER DISTRIBUTION SYSTEM FOR SRINAGAR TOWN
DESIGN OF WATER.pdf (Size: 1.86 MB / Downloads: 249)
ABSTRACT
After the water has been properly treated and made safe and wholesome, it has to be supplied to the consumers in their individual homes. The water has to be taken from the treatment plant to the roads and streets in the city and finally to the individual houses. This function of carrying the water from the treatment plant to the individual homes is accomplished through a well planned distribution system. A distribution system may, therefore, consists of pipe lines of various sizes for carrying the water to the streets; valves for controlling the flow in the pipes, hydrants for providing connections with the water mains for releasing water during fires; meters for measuring discharges ; service connections to the individual homes; pumps for lifting and forcing the water into the distribution pipes, distribution or service reservoirs for storing the treated water to be fed into the distribution pipes etc. Further, the water may be supplied to the public either continuously for all the twenty four hours of the day, or it may be supplied intermittently during certain fixed hours of the day. Also, the water may be pumped directly into the distribution system or it may be first stored in a distribution reservoir and then fed into the distribution pipes.
INTRODUCTION
Distribution system infrastructure is generally the major asset of a water utility. The American Water Works Association (AWWA, 1974) defines the water distribution system as “including all water utility components for the distribution of finished or potable water by means of gravity storage feed or pumps though distribution pumping networks to customers or other users, including distribution equalizing storage.” These systems must also be able to provide water for non potable uses, such as fire suppression and irrigation of landscaping. After complete treatment of water, it becomes necessary to distribute it to a number of houses, estates, industries and public places by means of a network of distribution system. The distribution system consists of pipes of various sizes, values, meters, pumps etc. The following are the requirements of a good distribution system-
(1) It should convey the treated water up to the consumers with the same degree of purity.
(2) The water should reach to every consumer with the repaired pressure head.
(3) Sufficient quantity of treated water should reach for the domestic and industrial use.
(4) It should be economical and easy to maintain and use.
(5) It should be able to transport sufficient quantity of water during emergency such as fire fighting etc.
(6) During repair work, it should not cause obstruction to the traffic.
(7) It should be safe against any future pollution.
TYPES OF DISTRIBUTION SYSTEM:
The distribution system is a critical component of every drinking water utility. Its primary function is to provide the required water quantity and quality at a suitable pressure, and failure to do so is a serious system deficiency. Water quality may degrade during distribution because of the way water is treated or not treated before it is distributed, chemical and biological reactions that take place in the water during distribution, reactions between the water and distribution system materials, and contamination from external sources that occurs because of main breaks, leaks coupled with hydraulic transients, and improperly maintained storage facilities, among other things. Furthermore, special problems are posed by the utility’s need to maintain suitable water quality at the consumers tap, and the quality changes that occur in consumers plumbing, which is not owned or controlled by the utility.