Minimum Velocity and Water Quality
Minimum Velocity and Water Quality
(OP)
Does anyone use (or know of) minimum velocity criteria when designing new potable water distribution systems to maintain water quality (ie water age).
Thanks in advance for any comments.
Thanks in advance for any comments.





RE: Minimum Velocity and Water Quality
In most cases, complaints of taste and odour were common with the water that had no flow for a period of time.
KRS Services
www.krs-services.com
RE: Minimum Velocity and Water Quality
For water stored in tanks for long time, there is a rule of thumb to circualte water from tank to tank atleast once a day and check for free chlorine.
Similar logic applies to pipeline. If flow exist take a daily sample for free chlorine analysis, otherwise if water is stagnant keep flushing for few minutes and take the sample for bacteriological analysis. Replenish chlorine if required.
For Velocity calculation in water system use the following equation :
V = Q / A ; whereas for circular pipes A= 0.785 D x D
V = Velocity in m/s
Q = Flow in Cubic Meter /sec
A = Area of cross section in Sq.m
D = Daimeter in meters
Usually you design the distribution network with minimum of 0.5 m/s and maximum of 2 m/s for uPVC 10 - 16 bar rated pipe