Technical causes and impacts of intermittent water distribution

Centralized water distribution in developing countries continues to be fraught with great difficulties. One major deficiency is the intermittent distribution of water. Most distribution systems were originally designed for a continuous supply mode and are now operated intermittently because of various constraints. In this mode of operation, the piping system is supplied with water for limited periods of time and is not filled with water under pressure continuously as originally provided for in the technical design concept. Periodic filling and draining of the pipe system is associated with numerous negative consequences which ultimately aggravate or prevent sustainable safe water distribution. To overcome this problem, thorough knowledge of intermittent water distribution is required. This paper discusses possible causes and consequences, and their interactions. These considerations are largely limited to the technical side of water distribution and are mainly based on the technical literature in the field.