madgardener wrote:

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My sprinkler system feeds of the 'pond' behind my house. Is it safe to
water 'food' with water from this pond. Since all the pond is, is an
water retention pond that is refreshed with road run off from rain.


well until you said it was a water retention pond that is refreshed from
road run off, I would have said fine. But roads have tars, petroleum
residue's, gasoline residue's, etc. To use that runoff water would put you
at risk watering your edibles with it. Trace metals and chemicals. Better
that you put a plastic barrel or rain catcher under your downspouts to
capture rain water in it's semi pure form and use that to water your food.

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Actually, the pond water should be fine, provided you do two things: 1)
Make sure your pump's intake is well below the water surface. Oil, gas,
etc. will form a thin layer on the water surface, so having your intake
sufficiently below the surface avoids these nasties. 2) Do NOT position
the intake so close to the substrate that you take up mud. Most (i.e.
almost all) the heavy metals from road runoff adsorb to soil particles.
Avoid sucking up the silt at the bottom of the pond and you will
successfully avoid adding heavy metals to your garden. ....
Furthermore, using the pond water will also add small crustaceans and
algae to your garden (the crustaceans, by which I mean zooplankton, will
die when removed from the pond).. The post to which I am replying
suggested that aquarium water and algae are both beneficial to gardens,
so why not take both from a large outdoor "aquarium"?

Of greater concern in Florida is salt. In the North, salt in runoff is
a problem because it is laid down on roads to control ice during the
winter. In coastal areas (all of FL), the sand may contain enough salt
to make the pond water too salty for your garden. This is a question
for your local extension agent or a friend with a sal****er aquarium -
get him/her to test the salinity of the pond water for you.

The raincatcher/barrels idea is OK except for one major problem in FL -
West Nile Virus. If you have a cistern of any type, make sure it has a
good lid that mosquitoes can not easily penetrate.

Hope this helps,

Norm