Refilling Water Containers Safely

The following is a guideline for safely re-filling water storage containers after a period of storage (or if the cleanliness of a container is questionable before filling). These guidelines will help eliminate possible bacterial contamination new or re-filled water storage containers that have been used only for water storage. See Technical Bulletin ”Choosing a Water Storage Container” for container guidelines.

1. INSPECT THE CONTAINER:  Empty old water from the drum or other container and inspect for contamination.

  • Using a flashlight if necessary, visually inspect inside of the container and check for any sign of algae, residues, discoloration, or odor.
  • Feel the inside surface with your finger and check for any slime on the inside surface.

2. INSPECT AND/OR REPLACE THE CLOSURES: All closures, drum bungs must have gaskets, and screw caps must have liners in good condition for a positive air tight seal.

  • Inspect all gaskets and ensure they are in good condition. Look for worn, cut, deformed or brittle gaskets and replace them before reusing the container.

3. DISINFECT THE CONTAINER:  Disinfection is recommended when re-filling any container after storage, or if the cleanliness of a new container is not known. If any of the conditions in Item 1. above are present, the container must be disinfected in the following manner:

  • Prepare a solution of 1/2 cup of common liquid household bleach to one (1) gallon of water. Pour a quantity of the solution into the container. (Use about 1/4 cup or more of the solution per gallon of container volume. (For example: use about (1) gallon of the solution for a 55-gallon drum, or 1/2 cup for a 5-gallon container).Caution: Use appropriate eye, skin and clothing protection when working with bleach or the bleach solution.
  • Replace all bungs and caps tightly and then rotate container in all directions to wet all inside surfaces. Let stand for 30 minutes or more.
  • Empty container and rinse thoroughly 2-3 times with clean water.
  • Re-inspect the container. Repeat steps 3(a), (b) and (c) above if any residues remain.

4. RE-FILL:  Follow the entire standard filling procedure, precautions, and container specification guidelines in the “Directions for Use” included in the Water Preserver package.