In what could be construed as understatement, the technician
from the independent lab which performed the second test wrote
under the comment section; This water shows salt and
mineral levels which could be detrimental to freshwater fish
I called Jim Purcell at Oregon Aquatics again with these results
since he has experience with hard water and aquatic plants. He
mentioned that water hyacinth and lotus are particularly sensitive
to hardness, and start showing signs of severe distress at levels
as low as 1200 ppm. The pond above tested for hardness at a whopping
3750 ppm which handily explains the rapid expiration of the hyacinths
when first introduced.
Since the pond in question is a closed system, the salt and
mineral levels will continue to rise as these recent results
seem to suggest, and the fish are already starting to die off
this year, presumably as a result of the increased toxicity.
The annual rainfall in this part of Texas is only 15 inches (38
centimeters) per year, so the possibility of a partially mitigating
freshwater infusion, or even a rainwater harvesting system doesnt
seem too practical.
What caused this saltwater intrusion into the groundwater?
There doesnt appear to be sufficient data at this point
to be certain, but geologist and Victoria Adventure list subscriber
Aaron Hicks in an earlier statement had this to say about a possible
cause ... since this problematic pond is situated in the heart
of Texas oil and gas country;
I hail from natural gas country in western Pennsylvania;
with the natural gas frequently comes "brine," a salty
solution that must be captured and disposed of properly ... These
salts are left behind from the oceanic deposits which form the
shale layers, which then undergo post-depositional changes that
produce the hydrocarbons we value so highly, i.e.: natural gas
and oil. These products are pumped together (hydrocarbons + brine),
the brine set side for reinjection into other wells that are
usually dead for many years, and the natural gas and oil then
go on to make valuable products like shiny plastic junk.
"With this in mind, a repeat water test -- along with
a panel for heavy metals -- is recommended. Either the well has
tapped into marginally saline waters, or there is some oil/gas
drilling contamination or drainage or somesuch.
"I would suggest the reason why the terrestrial plants
are doing OK is that the exchange capacity of the soils is, for
the time being, accommodating these element problems. If the
area is desert dust-to-lawn, the surface soils are probably reasonably
accepting of these ions, but their capacity will likely be met
at some point. From there, they too may succumb. The pond plants,
with a very low soil:water ratio, have met their match already
Michael followed all of the VA groups earlier collective
recommendations* except the heavy metals test which might have
confirmed Aarons theory. He didnt taste the water
either, and after seeing the test results, perhaps its
better that he didnt? The comments from the testing lab
tech appeared to obviate the need for an extension agent to independently
evaluate this situation.
* A) Repeat the water tests and include salinity, heavy
metals, & copper
B) Taste the water ... hey ... you're a CAC!
C) Forward the test results, assuming the new ones are consistent
with the previous ones -- to the local extension agent and have
him come out there if he will. This is a free resource so why
I really dont know what can be done at this point to
salvage this pond as salt and mineral levels are
likely to keep increasing, making even saltwater tolerant plants
a questionable proposition at some point if not already ...
If anyone has any ideas that would help Michael at this juncture,
please write WGI or share them on the Victoria Adventure email