Safe Use of “Tanker” Water for Dialysis

To use tanker water for dialysis, consider the following:

For the Water Hauler/Supplier

• The supplier should verify that the water being delivered meets Environmental Protection Agency (EPA) drinking water standards. If the water supplied is safe for consumption, then it may be used as source water for a water treatment system. The source for emergency trucked water must come from an approved public water supply. Other sources of water (i.e., private well) can be used only if shown to be safe to use by bacteriological, and possibly chemical and radiological testing, and approved by the state drinking water authorities.
• Commercial milk or potable water tanker trucks are preferred. However, trucks designed for the transport of wine, vegetable oil, beer, or other food products may also be used.
• The truck container must be contaminant-free, watertight, made of an EPA, Food and Drug Administration (FDA), or National Sanitation Foundation (NSF) approved water- or food-grade material (can only be used for transportation of items for human consumption) that can be easily cleaned and disinfected.
• To ensure that water-hauling equipment is adequately disinfected before using, the tank or truck container, along with all hoses, pumps, and other equipment, must be cleaned and then sanitized by a sanitizer listed in 21 CFR 178.1010. These sanitizing solutions shall be used in accordance with the EPA-approved manufacturer’s label use instructions. Normally, these sanitizers will be chlorine, iodine, quaternary ammonium, or acid-based aqueous solutions. If disinfectant other than a chlorine-based chemical was used, the supplier should ensure that the tank was thoroughly rinsed to remove residual disinfectant. A test should be done by the contractor to ensure minimal residual levels of the disinfectant.
• Water to be transported by tanker trucks should contain a free chlorine residual of about one part per million (1 ppm) and not more than 4 ppm at the beginning of the haul. This is done by adding 5-6 tablespoons (2.5 – 3 ounces) of common household bleach to each 1,000 gallons.

At the Dialysis Facility

• An additional pressure pump may be needed. Sometimes the tanker truck or water buffalo will have a pump, but if not, the local system may not be able to push this water through the pre-treatment chain with enough pressure and volume to run the reverse osmosis (RO).
• Connect the tanker supply line to the local pre-treatment chain. Minimum requirements for pre-treatment include carbon filtration and monitoring for chlorine or chloramine breakthrough. An optional step is to consider the addition of a multimedia sediment filter on the input to the water treatment system, in case the tanker was not adequately flushed of all particulates.
• Water will be at ambient temperature rather than blended to the usual 76-78°F. If the water is cooler, carbon may not remove chlorine/chloramines as efficiently. Additional carbon filtration may be needed during this time.
• Determine the chemical contaminants in the supply water. If possible, get at least a minimum chemical analysis of the tanker supply water. Focus on those contaminates which have a direct effect on patients (e.g., aluminum, fluoride, copper, chlorine and chloramines). Many of these can be tested on-site with test kits (e.g., HACH Company, LaMotte Company, Orion, etc.) or samples may be sent to a state water quality lab or an approved renal lab. The samples that are sent to a water quality lab should be stored at 4-6 o C and analyzed within 24 hours.
• If using untempered water, the RO will not be functioning at optimum condition. You may a drop in percent rejection and permeate flow rate so that some chemical contaminants may pass through the RO at higher levels than normal and product water flow may be lessened.
• Using a lower dialysate flow rate may be necessary while the water supply is reduced.
• Compare product water quality readings to any historical data. A significant difference could mean that RO membranes are damaged, or the quality of the incoming water has drastically decreased (see Note below). If the total dissolved solids (TDS) are more than 20% higher than the historical readings, deionization (DI) tanks may be needed as a polisher on the product water, followed by an ultrafilter to minimize microbial contamination. (See next paragraph.)
• If only DI tanks are being used, the water should then be treated with a UV-irradiator and a pyrogen filter or an ultrafilter to destroy and remove bacteria and endotoxins. Make sure the DI product water is continuously monitored and producing water that is ≥ 1 megohm-cm specific resistivity (or conductivity of ≥1 microsiemen/cm).
• Monitor carefully the water levels in the tanker to ensure an adequate supply of water for the entire dialysis treatment(s). As the water level in the tanker drops, try to secure a replacement tanker and get a water analysis of that water, to prevent further disruption of service.
• Increase your frequency of monitoring:
  • Check chlorine/chloramine with each new delivery of water.
  • Verify hourly that product water quality is acceptable.
  • Monitor water cultures and endotoxin at least weekly. If possible, test for endotoxin on-site daily.

The medical director is ultimately responsible for the quality of the water the facility uses for dialysis. Involve medical directors early: it may be better to dialyze patients for a few treatments with water that may not quite meet usual standards (Association for the Advancement of Medical Instrumentation or AAMI) than not to dialyze, as hyperkalemia and fluid overload can be life-threatening, whereas a low level of aluminum exposure can probably be tolerated for a short period.