Actually you made it sound pretty attractive. It's only $160 billion (plus a few for yearly maintenance why not) to get California entirely on renewable energy. That's amazing and gives me hope.
In addition, take into account the enormous amount of moving parts. Maintenance everywhere! Compare the tracks with carts to a large pump/generator and pipelines with water I guess the latter is much simpler to maintain and better looking to the eye. While train tracks should be kept clear of people you could easily see people using the lakes up & down the mountain for recreation.