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Name: Mary
Status: other
Grade: 12+
Location: FL
Country: USA
Date: Spring 2011

My home water shows the same chlorine level as my pool water on the test kit. Will this harm my lawn or kill the grass seed and prevents them from coming up?

The grass seed will still germinate and grow. The chlorine dissipates. The problem of chlorinated water sometimes affecting the appearance and health of the grass could be a concern mainly for areas continuously exposed to chlorine such as around pools. The following should be helpful:

Anthony R. Brach, PhD Missouri Botanical Garden c/o Harvard University Herbaria

One or the other of your test kit is giving an error. You would find drinking water having the level of chlorine found in a swimming pool very nasty to drink. So your test kit must be giving a false high reading. That is not unusual for colorimetric swimming pool test kits. Watering your lawn/garden is not advisable generally. The pH may be wrong. Have your drinking water and pool water tested by a professional. Something isn't right.

I notice you are from FL. You get a lot of sunlight. This can cause large errors in the chlorine test.

Vince Calder

Chlorinated water should not do your lawn any harm, but I am concerned that the level in your tap water is the same as the pool.

Both tap water and pool water are chlorinated to kill bacteria and other micro-organisms, and to reduce body wastes in the pool. Chlorine will effectively deal with dead skin cells etc, and urine that somehow manages to find its way into most swimming pools (although NO-ONE seems to ever know how!!) Since the body waste issue does not apply to tap water, there should be no need for the same level of chlorination. What kind of test kit did you use? If it is designed to test tap water, you may have reached a maximum level with the tap water, and then exceeded that level (but with no further test change) with the pool water. If you have used a pool test kit, then there are a few possibilities - Your kit is old and the chemicals are stale. - your pool is badly under-chlorinated. - Your tap water is severely over-chlorinated.

Without knowing the results of your tests it is impossible to know.

Nigel Skelton Lab Technician Barkly College - Secondary

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