The idea is good in principle. However, the investment cost per person is quite staggering. In a range of USD 1,000 per person (or more, there is a lot of uncertainty in the numbers). Even considering local costs in the US, it seems a better approach for the Navajo Nation to just purchase compact filters using reverse osmosis technology and install them in each home, with a far lower expense.
I like the approach of providing clean piped water as usually rural water projects are family based solutions (we use this last approach in our own work in Mexico). However, piped water supplies in rural areas have an associated problem concerning the disposal of waste water from the homes. This is a huge challenge and requires investing in adequate waste water facilities (latrines don´t work if too much water is used in the homes). Waste water issues are sometimes more difficult to solve than potable water issues.
The initiative is very inspiring, but the economics of this initiative are not very clear. Apparently several 1,000´s of young people have benefited from the program, but the resources spent so far are in the range of a 1,000,000 USD? This seems like a very high amount for the number of students benefited.