often should I test my water?
you get your water from a private source, periodic
testing of the water for potentially harmful constituents
such as bacteria, nitrates or heavy metals will determine
whether or not your water is safe for consumption.
Most health agencies recommend having your water tested
at least annually however it is advisable to increase
the frequency of testing if you notice any changes
in the aesthetic quality of your water (for example;
odor, taste, clarity, etc.). Also, have your water
tested if you have had any work done in or around
the well such as replacing or servicing the pump and/or
drop pipe as this activity can introduce bacteria
into the well.
water test failed. Do I have to install a treatment
not! If you had your water tested at a Licensed and
Certified Laboratory, and the results came back positive
for Coliform Bacteria, AND you have a drilled water
well, the well may just need to be "shocked"
and re-tested. If the water test showed the presence
of E-Coli bacteria, it is advisable to have the well
inspected by a N.Y.S. Registered Water Well Contractor
or Certified Water Specialist for a source of contamination.
If the water comes from a spring or dug well , water
treatment with an approved disinfection system is
recommended due to the fact that dug wells and springs
are difficult if not impossible to protect from surface
is Well Shocking?
shocking is the process of disinfecting a water well
to kill unwanted micro-organisms that have entered
the well and may contaminate your drinking water.
Shocking a water well may also protect the integrity
of the well itself from premature failure due to slime
forming bacteria such as Iron or Sulfate Reducing
Do I Shock My Well?
is a right way and a wrong way to shock a well. To
shock a well correctly, it is important to first understand
the process of chlorination and how it affects the
well . The purpose of chlorinating the water well
is to create a powerful chlorine residual of "free
available chlorine" or Hypochlorous Acid and/or
Hypochlorite Ion in the water. Bacteria are not killed
just by adding chlorine to the water. The chlorine
must be added to the breakpoint level at which all
oxidizeable substances have been oxidized so that
they no longer place a demand on the chlorine. At
this point, a free available chlorine residual has
been attained and the further addition of chlorine
will yield an increased level of free available chlorine
may all sound complicated, but its really not
that difficult. The idea is to kill bacteria in the
well itself so that a retest of the water will determine
if the bacteria are in the aquifer "water supply"
or have just found their way into the casing from
properly shock a water well, it is helpful to know
the depth of the well along with the wells recovery
rate. The higher the recovery rate, the easier it
is to purge the well of sediment, debris and chlorine
without fear of running the well dry and potentially
damaging the pump or the well itself.
you will need to shock your well:
hoses long enough to reach the well from an outside
5 Gallons of unscented 5.25 percent chlorine household
bleach or at least 2 gallons of 12 percent full
strength pool type chlorine. Why so much chlorine?
These are estimated amounts but vary depending on
the depth of your well, the amount of water in it,
the recovery rate and more importantly
chlorine demand of the water. If you are unsure
of the exact amount of chlorine you will need, it
is better to have more than you need than not enough.
A white 5 gallon bucket.
Pool type Chlorine Test Kit.
kits can be helpful because despite what you may have
heard, you cant smell "free available chlorine"!
What you can smell is Chloramine or Combined Chlorine.
Chloramine and Combined Chlorine are formed when you
chlorinate water but they have limited disinfection
capabilities. What we are after is free available
chlorine otherwise known as Hypochlorous Acid which
you can not smell!
the well isnt a mile away from the house and
you have enough hose to reach the well! If so, you
are ready to get started. Pick a good time to shock
the well because the water quality may be very poor
for a few days after you shock it. The turbulence
and chlorine may loosen up and free loads of iron,
metalic sulfide and silt from the well and this will
pretty much guarantee some ruined laundry if it is
done within a few days of the shocking program.
to shock a well:
get started with bypassing any water filters, softeners
or other water treatment equipment that may get
plugged by sediment or ruined by high chlorine doses.
Connect garden hose to house and place other end
inside the water well. Turn on spigot and let water
run back to well for approx. 30 minutes.
After 30 minutes of running water down well, remove
hose and run some water into your bucket and note
changes in color or clarity. The water may be turbid
from sediment that was rinsed from casing. If this
is so, run water from hose away from well for 20
minutes or so. This will reduce the chlorine demand
of the water by minimizing the turbidity in the
Add ½ a gallon of full strength chlorine
or 1 gallon bleach into empty bucket and then add
a couple of gallons of water from hose into the
bucket. Pour this solution down the well and replace
the hose end into well. Allow water to run down
well for approx. 30 more minutes.
Remove hose and run water into bucket. Note color,
odor and clarity of the water. If the water appears
highly turbid or smells of strong chlorine, test
the water with your chlorine test kit. The color
of the water in vial should be "blood red"
after you add the OTO drops per instructions on
the test kit. If this is the case, turn off the
water spigot and let the well stand 12-24 hrs with
minimal use. If not, repeat step # 4 until the residual
is established. Special
Note: If possible, now would be a good time
to add a couple hundred gallons of chlorinated water
into the well to force the disinfected water back
into the formation! This is a trick I have been
using for several years and is particularly effective
when you are dealing with Iron bacteria.
Now that this shocking dose of chlorine has had
at least 12 hours to do its work, turn on garden
approx. 2 gallons per minute. You can use your bucket
and a watch to establish this flow. Run the hose
away from the well to a place where the strong chlorine
will not damage gardens or other environments and
allow water to run for several hours. Check the
water flow every 15 or so minutes to insure that
the well hasnt run dry. If this happens be
sure to shut off pump power supply!
With your test kit, check chlorine residual every
½ to 1 hour. When the Free Chlorine residual
drops to approx. 5.0 PPM , shut off hose.
Go inside house and place water treatment equipment
except carbon filters back into service.
Run water slowly through all hot water faucets until
a chlorine residual is established with your test
Now run water through all the cold faucets until
a chlorine residual is established. Dont forget
outside faucets, laundry tubs and washing machines.
Flush all toilets.
Let water stand in pipes for several hours. The
longer the better!
After allowing the water to stand in pipes for several
hours, the water can now be used for normal activities
but delay your laundry until the water runs clear
on hot and cold faucets and is free of chlorine.
Note: This may take several days depending
on chlorine demand, depth of well, volume of water
in the well and recovery rate of well.
Water can be re-tested for potability 1 day after
chlorine residual is no longer detected with your
If the water test passes and the water is potable,
it is wise to retest in a month or so to be sure
that the bacteria have not returned.
Some wells are very difficult to shock and may take
several days to clear after shocking procedure.
the water fails a bacteria test after this shocking
procedure has been performed, it is advisable to have
a Certified Water Specialist or NYS Certified Water
Well Contractor inspect the well for potential sources
of contamination or to make recommendations.
here for Coliform and E.Coli Bacteria
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