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THE KANSAS LIFELINE
July 2018
s spring turns to summer, many
systems must adjust their
treatment methods to maintain
an adequate amount of residual chlorine
throughout their distribution systems.
Longer hours of sunlight and warmer
air temperatures can heat water stored
in water storage tanks which in turn
results in a deterioration in the residual
chlorine levels throughout the system.
Surface water systems also treat
influent water that is sometimes up to
80 degrees F.
Doniphan County Rural Water
District (RWD) No. 5 is one of many
systems that must adjust the treatment
method accordingly with the onset of
warmer weather. RWD 5 does not
pump or treat their own source of
surface water or groundwater. Instead,
RWD 5 obtains water from Missouri-
American Water, whose primary source
of water is wells along the Missouri
River at St. Joseph. While Missouri-
American delivers treated water with
adequate chlorination to RWD 5’s
pumphouse in Wathena, RWD 5 must
rechlorinate that water before it enters their distribution
system in order to maintain adequate levels throughout the
system, including water sold to neighboring Doniphan
County RWD No. 2. RWD 5 typically has to rechlorinate for
only about three months each year, usually from about July
1 to September 30, depending on weather conditions.
RWD 5 uses ammonium sulfate and sodium hypochlorite
in their treatment process. The consequences of improperly
mixing these chemicals can be dangerous, if not
catastrophic. Since their water treatment equipment may be
idle for nine months of the year, a thorough overhaul is
conducted every spring to ensure that their equipment works
as needed, when needed. Such
equipment has tubing that may become
brittle with the use of chlorine and the
cold temperatures during idle months.
For several years, RWD 5 and
numerous other systems have turned to
the Kansas Rural Water Association
(KRWA) to provide technical assistance
and help bring the water treatment
systems back into proper operating
condition. This involves items such as repairing positive
displacement pumps, peristaltic pumps, chlorinators,
replacing valves and injectors, along with replacing all
feedlines and pressure transducer lines. KRWA recently
provided such assistance to Doniphan RWD 5 and in the
process tries to also train the operators on the equipment.
Once completed at Doniphan RWD 5, similar assistance
was provided to Doniphan County RWD No. 2.
Most chemical feed pumps have design limitations due to
a variety of chemicals. For example, some may only be
designed to inject aluminum sulfate (alum)‚ ferric sulfate‚
hydrochloric acid‚ magnesium hydroxide‚ 10 percent
By Lonnie Boller, Technical Assistant
The consequences of
improperly mixing
these chemicals can be
dangerous, if not
catastrophic.
A
KRWA Assists Doniphan County
RWDs with Overhaul of
Rechlorination Systems
KRWA Tech Assistant Lonnie Boller and Roger Engemann, Operator for Doniphan
RWD 5, work at retubing peristaltic chemical feed pumps.