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Description:
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As the world population increases , the demand increases for quality drinking
water . The harvesting of rainwater has the potential to assist in alleviating pressures on
current water supplies and storm water drainage systems . Diversion of a portion of the
collected water away from storage is a technique used to improve harvested rainwater
water quality prior to storage . Six configurations of a downspout first flush diverter
were constructed and tested in the laboratory . The configurations of diverters were
evaluated for their affinity to allow diverted water in the diverter chamber to interact
with the flow of water to storage . Experiments were conducted at flow rates ranging
from 0 .76 L /min to 113 .56 L /min . This range of flow rates adequately represents a wide
range of common storm intensity patterns across the United States to which downspout
first flush diverters are subjected .
The diverter chamber to downspout transition fittings tested on a 10 .16 cm
diameter diverter chamber , upward and downward oriented sanitary and straight tee , do
not have a significant impact on the mean difference in initial and final total dissolved
solids concentrations observed at multiple sample ports . No statistical difference was observed when comparing upward and downward oriented sanitary tees used as diverter
chambers to downspout transition fittings on 10 .16 and 15 .24 cm diverter chambers .
Utilizing a straight tee as a transition fitting with a floating ball , acting as a barrier
between water collected in the diverter chamber of a downspout first flush diverter and
the flow passing through the transition fitting , limited diverted water from interacting
with the subsequent flow of harvested rainwater . There is not a significant difference
between the use of a downspout first flush diverter with diverter chamber diameters of
10 .16 and 15 .24 cm utilizing upward and downward oriented sanitary tees as downspout
to diverter chamber transition fittings . Tests at flow rates less than or equal to 12 .11
L /min exhibited limited changes in total dissolved solids concentrations in the
downspout first flush diverters with 15 .24 cm diameter diverter chambers . Tests at flow
rates less than or equal to 1 .51 L /min exhibited limited changes in total dissolved solids
concentrations in the downspout first flush diverters with 10 .16 cm diameter diverter
chambers . The diverter chamber drain flow rate and volume impacts the observed
differences in initial and final TDS concentrations at all sample ports on the diverter
chamber of a downspout first flush diverter regardless of flow rate . The diverter
chamber drain flow rate impacts the flow rate of water entering the diverter chamber
through the transition fitting . |