Joint Base Lewis McChord Water Hardness & Quality Report (2026)

American Water Military Services supplies drinking water to Joint Base Lewis-McChord (JBLM), including McChord Field, serving approximately 54,822 residents in Pierce County, Washington. The utility draws water from eight groundwater wells that tap into local aquifers. To ensure water quality, the supply undergoes disinfection with chlorine (hypochlorite). Some facilities also utilize aeration and air stripping. Initial inventories revealed no lead service lines or galvanized lines needing replacement.

The water originates from aquifers within the Puget Lowland, a region shaped by the Puyallup River watershed and Pleistocene glacial deposits. These formations include Vashon Glacium outwash sands and gravels, which create productive aquifers, situated above the Tertiary Puget Group bedrock. This geological makeup, characterized by glacial and alluvial sediments, results in moderately mineralized water. The dissolution of minerals from these sediments imparts a distinct chemistry, influenced by the area's post-glacial hydrology and recharge from precipitation and river infiltration.

This level of hardness can lead to moderate scale buildup in appliances such as water heaters, dishwashers, and coffee makers, gradually reducing their efficiency. You might also notice laundry feeling stiffer and a less effective lather from soaps. To combat these effects, homeowners can perform regular maintenance, including annual deliming of heating elements and using vinegar soaks for fixtures. For households experiencing significant issues, installing a water softener is often recommended to extend appliance lifespan and improve cleaning performance, particularly in military housing where usage is high.