Just saw the cost to cure in real time. "The Dry-Redwater Regional Water Authority (DRWA) is designed to serve approximately 4,400 rural and municipal connections (nearly 15,000 residents) across Eastern Montana. The estimated total construction cost for the extensive pipeline and treatment system is roughly $630 million."
75% Federal dollars, 12.5% State dollars (probably from the Feds), and 12.5% County dollars, so it is free. At full usage, that works out to about $143,000 per connection. The DRWA was created in 2005, and some action is taking place in Congress, so about at 25 to 30 year wait for resolution.