by Rick Stryker
Name the piece of the camp operations puzzle that stops your camp's program
in its tracks. The answer is water. Whether we’re talking about
the water coming from the tap, going into the pool, or down the toilet,
every facilities director will admit that there is no crisis like a water
crisis. Its distinction as the critical element in sustaining life brings
special attention from health departments and other regulators, and justifiably
so. In fact, the increase in water-borne diseases at seasonal facilities
has caused some state regulators to amend the statutes to bring camps
and conference centers under much tighter scrutiny. The days are fast
passing where a simple, once-a-year test would suffice, and like so many
other areas of property management, compliance will require a higher level
of skill to implement and maintain. This article reviews several of the
most common parameters in water compliance regulations, what they might
mean to your water system, and some ways that they’re addressed.
Coliforms
Coliforms are organisms which commonly inhabit the digestive tract of
mammals, and “coliforms” are a common parameter on your water
tests. You may be surprised to learn that ingesting coliforms in the water
will probably not make you sick. Their presence is instead an indicator
of contamination by other microorganisms that are likely present. Because
it only takes a very small number of those other microorganisms to make
people sick, coliforms are considered the marker organism.
Testing for coliforms is (comparatively) cheap and fast, but the simplicity
of the test makes false positives quite common. This is why most health
departments require an immediate retest of a coliform “hit”
on the water test. The tester is normally extremely careful on the retest,
so a second positive normally indicates that the well is contaminated
with illness-causing bacteria.
Most often, the solution to a biologically contaminated well is to disinfect
the water at or near the well head with sodium chloride (or bleach). Do
not make the mistake of dumping bleach down the well and considering the
problem solved. Sometimes this will correct the problem, but normally
only when the opening of the well (“well head”) is arranged
such that surface runoff can wash into the well casing. Even in this case,
“bleach in the well” is only a temporary solution until the
next hard rain dumps more contaminated surface water down the hole.
If this is what’s happening at camp, take steps to correct the
problem by adding a physical barrier around the well head (like a concrete
manhole), divert runoff with a ditch or swale, and consider having your
local well driller inject a special grout around the outside of the well
casing to seal against inflow.
Most often, the problem with contaminated well water is that under-treated
septic liquid (“effluent”) from the drain field or a leaking
tank has found an underground pathway to the aquifer. Determining the
source can be an expensive, lengthy, and difficult process involving dyes
and lots of pumping. Installing a new well may solve the problem, but
if the well is installed near the contaminated one, you stand a pretty
good chance of tapping into the same contaminated aquifer. Some well drillers
may suggest “going deeper” which may be helpful, depending
on your local geology and the depth of the contaminated well.
There is a host of chemicals that can be used to disinfect drinking
water including ozone, but the most common is either chlorine gas or sodium
hypochlorite. Larger municipal systems tend to use gas, and smaller systems,
like camps, tend toward the liquid. (Incidentally, the common granular
pool disinfectant is CALCIUM hypochlorite, and should not be used for
water supply disinfection.) This requires that the chemical has to be
in sufficient concentration for a sufficient time (contact time) to kill
the microbes in the water.
Most regulations require that the chlorinated water remain in a holding
tank for at least thirty minutes to achieve the required disinfection
level and that a certain level of disinfectant remain in the water to
combat bacteria entering the system further down the line. Just like the
swimming pool disinfection system, though, balancing the injection rate
and solution concentration is partly science and partly art form. It will
take time to learn the equipment, the system, and how everything works
together.
Under limited circumstances, another alternative for water disinfection
is ultraviolet light. If microbes are exposed to 256 nanometers (nm),
their DNA is altered, and the microbes do not reproduce. This has the
benefit of not having to mix or inject chemicals, it is pretty fast (no
contact time per se), and there is no need to maintain a tank from which
to feed the disinfectant. The main disadvantage is that after the water
has passed through the UV unit, there is no residual disinfecting capability
in the water. Any bacteria which enter the system in pipe cracks or joints
can then multiply unchecked. In many cases, health departments require
that UV be supplemented with chlorine to provide that residual. Only where
the UV unit is being used to disinfect water at the point of use (already
inside the building) have regulators allowed unaugmented UV disinfection.
A Can o’ Worms
In some cases, additional treatment may be required even though the
only parameter violated is the bacteria count. For example, iron and manganese
are common background minerals in groundwater taken from rock wells. Even
if those levels are below the maximum acceptable level (according to your
health department), adding chlorine may cause iron and manganese oxides
to form making the water appear cloudy, rusty, or full of tiny black grains.
Although they don’t represent a health threat of any sort, there
are perceived quality issues here. Can you imagine the letters home describing
orange water (that wasn’t bug juice), that had black specks in it?
How about the conversation with the parent that would follow?
The solution is to filter these out with replaceable cartridges (or
a bed of special sand) just downstream of the holding tank, and in some
cases near the critical points of use as well (like the dining hall or
laundry). With proper holding time, the heavier particles will generally
settle to the bottom of the tank, but during high use periods, they’ll
remain in suspension.
Another pretreatment issue could be hardness. This is particularly important
where you are considering ultraviolet disinfection. If your water contains
a relatively high background content of minerals (particularly from the
carbonate family), you’ll notice soap scum buildup in the bathrooms
and showers and white scale in the kitchen particularly on the coffee
pot and the dishwasher. In short, if “Lime-Away” or “C-L-R”
are housekeeping chemicals you purchase often, you can bet that you’ll
have to soften the water before it goes through the UV unit. Failing to
install, operate, and maintain an efficiently operating softener will
almost guarantee that the scale will build up on the lamp cover inside
the unit, weakening the effect of the killing light.
In the End . . . .
There are a couple of things to consider as we wrap this up. First,
because they’re familiar with your operation and facility, your
engineers will be able to help you select the best disinfection method.
Do not rely on an equipment supplier or your plumber to help you through
this decision process. They make their living selling or installing a
certain brand or line of equipment, and most health departments require
that any changes to your system be designed by your engineer, and approved
before installation is made. Take advantage of the relationship you’ve
built with them, and if you haven’t signed your engineer yet, this
is a WONDERFUL opportunity to do it!
Finally, there is no disinfection solution that you could compare to
the Ronco™ Roaster whose motto is “Set it, and forget it!”
Chlorine solutions become weaker over time so their injection rate may
have to be increased. UV units come with wipers that must be used frequently
to ensure that the required 256 nm of light is penetrating the water.
Filtration systems require changing of filters, membranes, or backwashing.
These systems require knowledgeable and diligent operation every day.
Making sure that the nectar of life is safe to drink just became one more
“have to do” on the daily checklist.
Originally published in the 2005 May/June issue
of Camping Magazine. |
