T&T: potti-patrol

[Bill Fleenor]

Well, as a Ph.D. in environmental engineering there is little more I enjoy
than good potty talk.  Most of the miss-conceptions have been brought to
light but I remain concerned of the general boating public's understanding
of LectroSan treatment capabilities.  I frequently hear people mention that
the system treats water to higher standards than municipal wastewater
treatment plants (WWTP) and that is just not correct.  LectroSan breaks up
the solids but does nothing to eliminate them.  The solids concentrations in
boat waste are higher than those of WWTP influent simply because we are
stingier with our water use on boats.  WWTPs reduce suspended solids to a
maximum of 30mg/liter, while boat effluent will typically be in the
400-700mg/liter range.  In addition the presence of these solids greatly
reduces the effectiveness of the disinfection process.  Disinfection contact
time is also important in pathogen removal and high-use of a LectroSan could
prevent sufficient contact time - no big parties.  Even if the LectroSan has
sufficient contact time and disinfectant to treat the waste, it is unlikely
that encysted protozoa (Giardia or Chryptosporidium) would be deactivated.
WWTPs use filtering processes to remove these larger organisms and filtering
is not preformed in LectroSan units.  The biochemical oxygen demand (BOD) of
wastewater is reduced significantly in WWTPs before release into
high-dilution areas and there is no BOD removal in LectroSan systems.
Finally, we are now even requiring re-licensed WWTPs to remove some of the
nutrients (varies with need of receiving water), although this is done less
for those plants that are discharging to high-dilution coastal areas.

 

Bill Fleenor

Double-Wide