Mass Water Supply

Treatment
The nature and quality of the water source determine the intensity of water treatment for a particular supply and distribution.


 * Ground water treatment: Contents of components and minerals may not be suitable for human consumption and may not meet the technical requirements of the treatment and distribution system. If sources of water contain iron or manganese, these minerals must be converted into insoluble salts and then removed by filtration. Excess carbonic acids must be precipitated by lime or removed by filtration through marble gravel, Lime and soda treatment, followed by filtration through artificial resins is the treatment of choice for excess hardness of water. As for technical requirements, polyphosphates are added which dissolve Ca and Mg sediments thus preventing the coagulation of hard water in pipes.


 * Surface water treatment: this is a complex process involving the interactions between the physical, chemical and biological properties of water. The processes involved are as follows.
 * 1) Impoundment and  reservoir storage
 * 2) Clarification/ Coagulation
 * 3) Sedimentation
 * 4) Filtration
 * 5) Disinfection

Distribution
Water is conveyed via pipes. The driving pressure may be actively maintained by pumping or it may be passive if the reservoir is situated high enough compared with the areas it supplies, The areas around the distribution pipes must be kept free from pollution. To minimize chances of contamination (in the case of cracking of pipes), a positive pressure ought to be maintained within the pipes. Sewage and drainage pipes should never be constructed as to overly water distribution pipes.

Drinking Water Issues in the Czech Republic
Water quality in the Czech Republic has improved significantly within the last decade. However there is till need and room for improvement since, problems concerned with microbial contamination still occur. In addition, the documented presence of organochlorines (chlorination by-product) and the rising concentrations of endocrine disruptors in the water supply are increasing receiving attention not least due to the adverse health effects associated with these agents.

Advances:
 * 1) The elimination of stage V. level of water purity both in main water courses and large tributaries. Stage III. sites still exist as well as a limited numbers of stage IV. Sites.
 * 2)  70% decrease in organic pollutants released into water within the last decade.
 * 3) A decrease in the overall level of nitrates and phosphorus products over the decades. This is mainly due to the regulation of agricultural activities. For example, a decrease in the numbers of cattle bread and a decrease in the use of industrial fertilizers.
 * 4) Decreased pollution from point sources. 77.4% of Czech inhabitants are connected to the public sewage system.

Drawbacks:
 * 1) Pollution from municipal sources. For example, settlements with populations of 2000 –10000   inhabitants. This is due to the fact that it is not cost effective to build water treatment plants for such small populations.
 * 2) Area/ Diffuse sources are increasingly becoming a major source of pollution. (The opposite is so for point sources).
 * 3) Majority of waste waste-water treatment plants are not equipped with the third stage treatment facilities (concerned with the removal of nitrates and phosphorus.)

Related Articles

 * Individual Sources of Drinking Water