Hydro-Guard Automatic, Programmable Flushing Systems Improve Water Quality In Distribution Systems

Naples, FL — Most water distribution systems have areas where there are water lines that may not have sufficient demands to keep the detention time short enough to maintain minimum chlorine residuals. Failure to maintain minimum chlorine residuals in water lines, in addition to being a violation of State and Federal standards, also contributes to the conditions that favor growth of biofilms within the pipelines. Long-term exposure to low chlorine residual conditions within a water pipeline favors biofilm growth resulting in an increase in the demand for chlorine making it even more difficult to maintain the desired minimum chlorine residual. A recognized solution to this water quality problem within water distribution systems is periodic flushing of the pipelines. This process removes both the water that has low chlorine residual and the biofilm from the inside surface of the pipeline. Unidirectional Flushing is the traditional method that is used to perform this sort of periodic flushing for biofilm removal. However, Advanced Maintenance Flushing, a method developed by the engineering consultants at Hydro-Guard® and introduced in 1998, continues to become the more desired method due to its economic and conservation benefits.

Advanced Maintenance Flushing — which is accomplished through the utilization of an automatic and programmable flushing system like the Hydro-Guard®—minimizes low chlorine residual problems in water distribution systems by providing periodic flushing on a more regulated basis, in order to maintain the water quality in the distribution system between flushing events.

Smaller volumes of water used on a more frequent basis have been shown to be sufficient to maintain a minimum chlorine residual that in turn results in a reduction in the rate of growth of biofilms resulting in a reduced chlorine demand within the pipeline. A reduced chlorine demand in the pipeline in turn results in a longer detention time allowed prior to loss of chlorine residual within the pipeline. Implementation of Advanced Maintenance Flushing results in a lower amount of water needed to maintain water quality within water distribution systems and can be implemented in a fashion that requires less labor and lower cost than conventional flushing.

Numerous municipalities throughout the United States and Canada have been using Advanced Maintenance Flushing instead of conventional flushing. The results from each case study confirm the benefits of Advanced Maintenance Flushing relative to the reduction in labor and quantity of water used in flushing in order to maintain desired water quality. The Advanced Maintenance Flushing White Paper has been presented at conferences throughout the United States.

SOURCE: Hydro-Guard®