Building Principles: Don't Mistreat . . . Your Water!

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.

Rick Stryker is a professional engineer with Camp Facilities Consulting, providing study, design, permitting, and construction consultation services to the camp and conference center community. Camp personnel may contact him at 570-296-2765 or by e-mail at rstryker@ptd.net.

Originally published in the 2005 May/June issue of Camping Magazine.

 

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