Water - one of the key elements necessary to support human life and all living things on our planet. In parallel with the natural water cycle in this process actively participate artificial water system, designed and constructed by people. Water supply systems are internal and external.
Function of external water supply
External water network are an important element of water supply systems, providing an uninterrupted supply of public water and businesses. Feed resources on these systems are usually made from natural sources. Used as ground water (groundwater, springs and artesian) and surface water (rivers, lakes, reservoirs).
Groundwater usually fresh. Because they are used primarily in order of use. Surface waters may be either fresh or salted. These resources are used for technical purposes: in factories, agriculture
External water supply system supplies cold and hot water.
Types of water supply networks
Exterior in its purpose of water supply systems are divided into two types:
- Central water supply.
- Individual water supply.
Central water supply system provides simultaneous water supply a large number of consumers. Used in cities and towns. The pressure in such systems is formed by the use of water towers. For smooth water feeding (both cold and hot) to meet special centralized systems, utilities.
Individual supply designed for a small number of consumers. It may provide for exclusively private use. The widespread use of individual water storage tanks.
According to the type of water supply system design are:
- Branched (deadlock).
- Combined (both include the first and second embodiments).
Design and layout of external networks
Design of outdoor water supply network - this is very important and mandatory process, which is essential for the practical implementation of the upcoming work on the construction.
The three main stages of design:
- technical task;
- the design documentation;
- working documents.
Terms of Reference (TOR) - this is the original document. It made a list of all the conditions for the organization of work, determine the number of stages of design. The TOR defined the boundaries of work, a list of equipment and materials taken into account in the subsequent part of the project documentation.
Project documentation is developed design organization sufficient for passing the examination volume. Performed project documentation in accordance with the decree number 87 of the Russian Federation Government.
The working documentation is developed by the project organization sufficient for the construction volume.
When designing outdoor networks of water supply should take into account the presence of other present underground utilities. Location water supply in relation to other possible utility services should provide free access to them in case of need to perform repairs. In the event of damage to the water supply, it is important to exclude the possibility of undermining the foundations of nearby buildings.
For travel pipelines are laid strictly on the highway, in a straight line and parallel to the building line. All intersections of water supply systems should be carried out at an angle of 90 °. Allowable minimum distance between the water supply and structures depends both on the characteristics themselves of water supply (pipe diameter, pressure
The main factors that have an impact on the location of the outdoor water supply network:
- Features of the terrain.
- The presence of obstacles (railway, river
and so on. N.).
- The location and layout of residential areas and their sizes.
- The presence of vegetation.
No less important part of the project - a detail that is a network diagram. She symbols applied equipment, fittings, valves. When compiling, first determine the location of valves and hydrants. The valves must be located in a manner allowing to block the flow of water into separate areas, while continuing its inlet to the objects that require uninterrupted supply of water. Detailing is done schematically, not to scale. If necessary, the individual components are drawn separately on a larger scale.
SNIP requirements for external water supply networks
Building Regulations (SNIP) have a number of requirements, mandatory for execution at the design and construction of external water supply networks. Listed below are the most important of these rules:
- projects of water supply systems need to be developed in parallel with the project sewers;
- for drinking water supply systems need to provide sanitary-protection zone of water supply structures and water supply;
- the quality of the drinking water must meet state quality standards (SanPiN
- the quality of water used for industrial purposes must comply with the technological standards and requirements of the enterprise;
- the quality of water used for irrigation should comply with health and agro-technical requirements;
- temperature of cold water in the external water network systems should not go beyond 2 + ... + 25 ° C, the temperature of the hot +50 ... + 75 ° C
- allowable working pressure in the water system should be not higher than 0.6 MPa, not less than - 0.05 MPa;
- water supply systems should not violate compositions architecture;
- water must meet all electrical and fire safety norms and safety;
- not allowed to enter into the system from environmental contaminants that can degrade its performance;
- The noise arising during operation of the system and its components must comply with the requirements of SNIP "Protection against noise";
- selection of main technical solutions should be based comparison of several possible options.
Due to rapidly advancing civilization and new technologies, it is possible that there will be new types of water supply networks, new technologies for their construction in the future. Accordingly, it will be necessary to make certain amendments to building regulations relating to water supply systems. But will be adjusted only a few figures. But the main task - to ensure human, industrial and drinking water in the conditions of full security - remain unchanged.